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snd@lhc (scattering neutrino detector at the large hadron collider) is a compact and stand-alone experiment to perform measurements with neutrinos produced in the lhc in a hitherto unexplored pseudorapidity region of 7.2 < η < 8.6. the experiment is located in the tl18 (target line 18) lhc tunnel, 480 m downstream of the atlas detector interaction point. the snd@lhc detector is composed of a hybrid system based on an 800 kg target mass of tungsten plates, interleaved with emulsion and electronic trackers, followed downstream by a muon system. this configuration allows us to distinguish all three neutrino flavors, opening a unique opportunity to probe the physics of heavy flavor production in the lhc in a region that is not accessible to the atlas, cms, lhcb and faser experiments. the detector concept is also well suited to searching for feebly interacting particles via signatures of scattering in the detector target. the first phase of the experiment has been carried out during the ongoing lhc run 3, and the first data of the lhc run3 commissioning period are being processed and analyzed. | the scattering and neutrino detector at the large hadron collider in cern |
we propose a clean and precise measurement of the flavor dependence of the emc effect using parity-violating deep inelastic scattering on a 48ca target. while the emc effect has been known for almost 40 years, there are essentially no reliable experimental constraints on its flavor dependence. the proposed measurement will provide an extremely sensitive test for flavor dependence in the modification of nuclear pdfs for neutron-rich nuclei. a measurement of the flavor dependence will provide new and vital information and help to explain nucleon modification at the quark level. in addition to helping understand the origin of the emc effect, a flavor-dependent nuclear pdf modification could have a significant impact on a range of processes, including neutrino-nucleus scattering, nuclear drell-yan processes, or e-a observables at the electron-ion collider. the parity-violating asymmetry (apv) from 48ca using an 11 gev beam at 80 μa will be measured using the solid detector in its pvdis configuration. the apv provides a particularly sensitive method to obtain flavor-dependent effects in nuclear modification as it is a ratio of the weak-to-electromagnetic interactions, which gives access to ratios of quark distributions. in 68 days of data taking, we will reach 0.7-1.3 % statistical precision for 0.2 <x <0.7 with 0.6-0.7 % systematic uncertainties. the proposal has received conditional approval from jlab pac50 in 2022. | first measurement of the flavor dependence of nuclear pdf modification using parity-violating deep inelastic scattering |
neutrinos are elusive particles whose nature and properties are still mysterious. precision measurements of coherent elastic neutrino-nucleus scattering and experiments searching for neutrinoless double beta decay are expected to reveal more information about neutrino interactions with nucleons, its magnetic moment, its nature (majorana or dirac), its mass ordering and scale. the next generation of experiments employing cryogenic calorimeters - like ricochet phase-ii and cupid-1t - will require thousands of detectors to increase the sensitivity of the experiments to new physics. a tes-based read out, thanks to its adaptability to a multiplexed readout, is a very promising technology to scale up the mass while limiting the heat introduced in the cryogenic system by the cabling. a modular tes design has been developed in a collaboration of northwestern university and argonne national laboratory. it can be easily mass produced and employed with different target materials. in this talk, we will present the first demonstration of a li2moo4 detector equipped with a tes-based readout. nsf phy-2013203 and phy-2209585. | modular tes-based readout for ton-scale neutrino experiments based on cryogenic calorimeters |
heavy neutral leptons (hnls) are additional electroweak-singlet fermions with masses significantly above the mass scale of the standard model neutrinos. they show up frequently in extensions of the standard model, including the seesaw mechanism--an elegant solution to the small observed masses of sm neutrinos. hnls with masses in the mev to gev regime are the subject of many current and planned experimental searches. in this talk, we focus on hnls with a transition magnetic moment coupling to active neutrinos, hereafter referred to as `neutrissimos'. in this talk, we explore an explanation of the 4 . 8 σ miniboone anomaly based on neutrissimo decay to a single photon. specifically, we evaluate the consistency of such a model with the energy and angular distributions of the miniboone excess. we also derive world-leading constraints on neutrissimos using minerva elastic scattering data. the implications of this result with regard to the neutrissimo-based explanation of the miniboone anomaly are discussed. finally, we examine the sensitivity of upcoming neutrino experiments to neutrissimos, with a particular emphasis on the coherent captain-mills (ccm) experiment at the los alamos neutron science center (lansce). ccm uses a light-based liquid argon detector to search for the interactions of neutrinos and potential dark sector particles produced when 800 mev protons from the lansce accelerator collide with the tungsten target at the lujan facility. neutrissimos can also be produced in large abundance in such an environment--thus, ccm will be able to set world-leading constraints on neutrissimos using data collected from its ongoing three-year run. nwk is supported by the nsf graduate research fellowship under grant no. 1745302. | exploring heavy neutral leptons with transition magnetic moments at neutrino experiments |
candles used 48ca to study the neutrinoless double beta decay (0vββ) to explore the mystery of the universe, such as lepton number violation, majorana neutrino, and matter anti-matter asymmetry. the recent candles iii experiment achieved a lower limit on the half-life of 0vββ decay at 5.6 × 1022 years and the effective majorana neutrino mass of <= 2.9 - 16 ev at 90% c.l. however, producing large quantities of 48ca is challenging. utilizing laser isotope separation (lis) is crucial in overcoming this challenge and enabling the mass production necessary for the candles study of 0vββ. studies have shown that a laser diode with a single frequency of 422.792 nm can deflect 48ca from an atomic beam due to the isotope shift of 48ca and other isotopes. an atomic beam generator, laser irradiation unit, collection system, and monitor and control system are necessary for mass production. the use of microchannel capillaries can improve the performance of sheet-like atomic beam generators by reducing inter-atomic scattering and maintaining high beam intensity with a small divergence angle. the laser system, which utilizes multiple slave lasers, can produce a power of 2w and efficiently separate 48ca, achieving a production rate of 10 grams/year. the most effective materials for collecting and coating thin films are being researched. the new design for the main chamber that will increase production capacity to 2 mol/year and 300 kg/year will be presented. | development of laser isotope separation (lis) for 48ca toward the study of neutrinoless double beta decay by candles |
the coherent experiment measures coherent elastic neutrino nucleus scattering (cevns) with a multitude of different detection technologies at oak ridge national laboratory's spallation neutron source (sns). neutrinos generated by the sns have an energy below 50 mev, enabling coherent neutral current interactions in which the neutrino interacts with the nucleus as a whole. these elastic interactions result in nuclear recoils measurable with low-threshold detectors. in this talk, i will provide an overview of the recent experimental efforts including the liquid argon, high-purity germanum and sodium iodide detectors. in particular, i will show first results from the summer 2023 sns beam period with the newly-deployed hpge detectors. the low noise and excellent energy resolution make it possible to access a lower recoil energy region in comparison to the previous cevns measurements, with reduced systematic uncertainties. i will also discuss bsm physics analyses such as accelerator-produced dark matter and the future physics opportunities at the second target station at sns. u.s. department of energy. | measuring coherent elastic neutrino nucleus scattering with coherent |
with current and planned neutrino oscillation experiments, it has become increasingly important to develop an accurate theoretical understanding of neutrino-nucleus scattering and exclusive nuclear responses to weak probes. while there are accurate many-body methods to compute quasi-elastic responses to weak probes, they are computationally intensive and limited to the study of the inclusive responses. recently, the short-time approximation (sta) was developed for the study of nuclear response functions and has been used to compute electromagnetic responses in a <= 4 nuclei. this approach, involving a factorization of the response into a two-nucleon component and a spectator system, consistently retains important two-body physics and quantum interference effects while also making possible the study of exclusive response functions. in this talk, i will discuss the theory underpinning the sta and extensions of this work to calculations of the density response in the unitary fermi gas and the quasi-elastic neutral current response functions in 2h with the variational monte carlo method. this work is supported by the u.s. department of energy (doe) under contract no. de-sc0021027 and the doe nnsa stewardship science graduate fellowship program under cooperative agreement no. de-na0003960. | applications of the short-time approximation: the unitary fermi gas and neutrino-nucleus scattering |
we consider a model with a complex scalar field that couples to (e,μ) or (μ,τ) within the ``longevity'' window: [|ml1 - ml2|, ml1 + ml2] in which l1 and l2 are the two different charged leptons. within such a mass window, even a relatively large coupling (e.g. of the size commensurate with the current accuracy/discrepancy in the muon gμ -2 experiment) leads to long lifetimes and macroscopic propagation distance between production and decay points. we propose to exploit several existing neutrino experiments and one future experiment to probe the parameter space of this model. for the μ-e sector, we exploit the muonium decay branching ratio and the production and decay sequence at the lsnd experiment, excluding the parametric region suggested by gμ -2 anomaly. for the τ-μ sector, we analyze three main production mechanisms of scalars at beam dump experiments: the drell-yan process, the heavy meson decay, and the muon scattering. we explore the constraints from the past charm and nutev experiments, and evaluate sensitivity for the proposed beam dump experiment, ship. the latter can thoroughly probe the parameter space relevant for the gμ -2 anomaly. kunfeng lyu is supported in part by the doe grant de-sc0022345. | flavor-changing light bosons with accidental longevity |
in the study of rare event physics, such as neutrinoless double beta decay, it is important to understand potential background events. neutron-induced events can take place even deep underground. experiments that study the neutrinoless double beta decay of 136xe use material enriched in 136xe, but the material still contains a significant fraction of 134xe. one neutron-induced event is neutron capture on 134xe, which can emit gamma rays that have the potential to compton scatter into the q-value region of interest for 136xe double beta decay. in this study, we investigate neutron capture on 134xe by looking for gamma rays emitted from de-excitation from long-lived excited states of 135xe and the subsequent decay to 135cs. the xenon gas used was irradiated in the neutron beam at triangle universities nuclear laboratory, and the decays were counted in the low-background counting facility located in the duke physics building. we will report our results of the neutron capture cross section for incident neutron energies at 0.43, 0.8, 1.5, 2.0, 4.2, and 5.5 mev. nsf phy-1614348de-fg02-97er41033tennessee technological university office of research's creative inquiry summer experience. | measurements of the 134xe neutron capture cross-section between 0.43 and 5.5 mev |
the beta-decay paul trap (bpt) measures the beta-neutrino angular correlation coefficient a&betaν in the gamow-teller decays of 8li and 8b (decaying to 8be*-->2α) to search for a tensor component of the weak interaction, a beyond-standard model possibility. the new bpt mk iv trap reduces β-scattering by a factor of 4, a key source of systematic uncetainty, and has recently been commissioned with 8li with 2.7 million triple coincidence events. in addition, a complete detector characterization has been performed with an α beam to reduce systematic uncertainties associated with the silicon strip detector response. this new high-statistics 8li data set, coupled with the experimental advancements, will allow for improved sensitivity to a tensor contribution. in the near future, the bpt should be able to reach an uncertainty of ?|ct /ca|2 <= 10-3, though the theoretical understanding of the nuclear structure still requires improvement. we acknowledge the u.s. doe contract no. de-ac02-06ch11357 [anl], de-ac52-07na27344 [llnl], nsf grant no. phy-173857,phy-2011890, and phy-1913728, as well as the nserc, canada, application sappj-2018-00028, and the anl atlas facility. l.v. was supported by the nsf grfp under dge-1746045. | search for an electroweak tensor contribution using trapped 8li with the beta-decay paul trap mk iv |
there is overwhelming evidence that gravitationally interacting dark matter exists, but its identity and microscopic properties remain a mystery. current direct detection experiments have not made a definitive claim, and this motivates searching for dark matter outside the direct search region of interest. in particular, direct detection experiments lack sensitivity at low mass because of their detection thresholds. on the other hand, low-mass dark matter could be produced and boosted to high energies by accelerators. neutrino detectors have the requisite sensitivity to identify possible dark matter interactions in-time with the beam pulse and can reject other backgrounds. the miniboone-dm collaboration recently completed a low-mass dark matter search at the fermilab booster neutrino beamline. by steering the 8 gev proton beam off-target into the steel beamstop, the miniboone detector sees a significant reduction of neutrino backgrounds. this talk will show results from the first low-mass dark matter search in the nucleon quasi-elastic scattering channel. future analysis channels and prospects will also be presented. | the miniboone-dm search for sub-gev dark matter |
making high-precision measurements of neutrino oscillation parameters requires an unprecedented understanding of neutrino-nucleus scattering. in this work, we present the first charged current double-differential cross sections in kinematic imbalance variables. these variables characterize the imbalance in the plane transverse to an incoming neutrino. we use events with a single muon above 100 mev/c, a single final state proton above 300 mev/c, and no recorded final state pions. thus, these variables act as a direct probe of nuclear effects such as final state interactions, fermi motion, and multi-nucleon processes. our measurement allows us to constrain systematic uncertainties associated with neutrino oscillation results performed by near-future experiments of the short baseline neutrino (sbn) program, as well as by future large-scale experiments like dune. this material is based upon work supported by laboratory directed research and development (ldrd) funding from argonne national laboratory, provided by the director, office of science, of the u.s. department of energy under contract no. de-ac02-06ch11357. | first measurement of double-differential charged current νμ-argon scattering cross sections in kinematic imbalance variables with the microboone detector |
borexino, a large volume detector for low energy neutrino spectroscopy, is currently taking data underground since 2007 at the laboratori nazionali del gran sasso, italy. the main goal of the experiment is the real-time measurement of solar neutrinos, especially the low energy part of the spectrum. neutrinos are detected via neutrino-electron scattering in an ultra-pure organic liquid scintillator. the light generated by the interaction is detected by 2212 phototubes. during many years of data taking the experiment provided several remarkable results as the first evidence of pep neutrinos, the real-time detection of the pp neutrinos, the evidence of cno neutrinos, and the detection of antineutrinos from the earth. all these results are based on an accurate modelling of the detector's response and performances. the contribution shows the design, the modelling of the detector's response, and the performances. moreover it will be discussed how the performances and the response were studied by means of extensive calibration campaigns. | borexino detector performances |
neutrinoless double-beta decay (0 νββ) studies are both the best way to determine the majorana nature of the neutrino and determine its effective mass. the two main experiments searching for 0 νββ -decay of 136xe (q value = 2457.8 kev) are kamland-zen and exo-200. though both experiments have enriched 136xe targets, these targets still contain significant quantities of 134xe. recently, a new nuclear level was discovered in 134xe that decays to the ground state emitting a 2485.7 kev gamma ray. the γ-ray production cross section for this branch was found to be on the order of 10 mb for incident neutron energies of 2.5-4.5 mev. here, we have extended the investigation of this level to higher incident neutron energies, and further explore the potential neutron-induced backgrounds on both 134xe and 136xe for extended neutron energies. we will report our preliminary results for neutron inelastic scattering on 134xe in applications to 0 νββ decay searches. nsf phy-1614348, de-fg02-97er41033. | neutron inelastic scattering on 134xe at en = 5 - 8 mev |
a modular nai[tl] scintillation crystal detector array is designed to measure coherent elastic neutrino-nucleus scattering (cevns) and charged current interactions as part of the suite of coherent collaboration detectors deployed at the spallation neutron source at the oak ridge national laboratory. a cevns measurement on 23na will provide the smallest neutron number (n) result and when combined with cesium and argon measurements and a future germanium value, will test the expected standard model dependence of the cross section on n2. the measured functional dependence of the cross section on n2 will provide information on the form factor deviations from unity used in the calculations. simulation studies on 7 modules with ~ 3 . 4 tons of nai indicates a significance of about 3σ per year for a counting experiment on 23na. the detector design allows for a simultaneous measurement of the charged current, electron neutrino, inelastic scattering cross section on 127i that is sensitive to quenching of the ga coupling strength in weak processes with momentum transfer ~ 30 mev and relevant to neutrinoless double beta decay calculations. the physics program, design, deployment status and tests of the initial 5-module array will be presented. supported in part by nsf grant #2013205. | neutrino-nucleus scattering studies with the coherent multi-ton nai array |
neutrino-nucleus interactions can produce excited states that can de-excite by emitting particles, including neutrons. neutrino-induced neutrons (nins) produced in common gamma shielding material, such as lead and iron, can pose a background for coherent elastic neutrino-nucleus scattering experiments. additionally, nin production in lead is the primary mechanism for the helium and lead observatory (halo) to detect supernova neutrinos, and iron-based supernova nin detectors have been proposed. the coherent collaboration has deployed two detectors to study nin production in lead and iron to the spallation neutron source (sns) at oak ridge national laboratory (ornl). an overview of the detector design, signal predictions, and latest results will be presented. | updates on coherent's neutrino-induced neutron detectors |
nova is a long-baseline neutrino experiment optimized to observe the oscillation of muon neutrinos to electron neutrinos. it uses a high purity muon neutrino beam produced at fermilab with central energy of approximately 1.8 gev. nova consists of a near detector located 1 km downstream of the neutrino production target at fermilab and a far detector located 810 km away in ash river, minnesota. neutrino cross-section measurements performed at the near detector are affected by a large uncertainty on the absolute neutrino flux. since the neutrino-electron elastic-scattering cross section can be accurately calculated, the measured rate of these interactions can be used to constrain the neutrino flux. we present the status of the neutrino-electron elastic-scattering measurement; the analysis uses a convolutional neural network (cnn) to identify signal events reaching a sample purity of 89% and constraining the flux uncertainty by roughly 6%. | status of the measurement of neutrino-electron elastic scattering in the nova near detector |
during the last decade, nucleon knockout reactions have been a very powerful tool to investigate short range correlated (src) nucleon-nucleon pairs. src pairs account for almost all the high-momentum nucleons in nuclei. studying srcs can help us understand the nucleon-nucleon (nn) interaction at high momenta and short distances, the structure of nucleons and nuclei, neutrino-nucleus interactions needed to interpret oscillation measurements, and the structure of neutron stars. nucleon knockout measurements of srcs were performed using different high momentum probes: using proton-nucleus and electron-nucleus scattering at brookhaven and jefferson lab, and most recently, using nucleus-proton inverse scattering at dubna (jinr). these experiments unveiled many important properties, such as neutron-proton pair dominance due to the tensor part of the nn interaction, src universality, study of asymmetric systems, and a possible explanation of the origin of the emc effect. this talk will present an overview of nucleon knockout measurements, recent results, and future prospects. | short-range correlations studies using nucleon-knockout reactions |
the numen experiment points to measure double charge exchange reaction (dce) cross sections with heavy-ion beams interacting with specific isotopes of interest for neutrinoless double beta decay process (0νββ). to achieve this, numen requires a complete upgrade to magnex spectrometer in infn-lns and a high intensity ion beam. this work focuses on the design of a new scattering chamber where the ion beam will interact with the target precisely positioned by an automatic system. the target will be cooled by a custom system based on hopg and a cryo-cooler. the fist integration of the chamber with all its components has been done at infn section of turin to check compliance with the requirements and to study the procedures for the target replacement. some results of this tests will be presented. | integration of the scattering chamber of the numen experiment |
dual-phase xenon time projection chamber (tpc) detectors are leading the weakly interacting massive particle (wimp) dark matter searches. a better understanding of the low energy nuclear recoil (nr) response in liquid xenon (lxe) will allow experiments to be increasingly sensitive to light dark matter and coherent neutrino-nucleus scattering. the michigan xenon detector (mix) is a small dual-phase tpc (140 g active volume) with 3d position sensitivity. mix possesses light gains of (0.239+/-0.012) pe/photon and charge signal gains of (16.1+/-0.6) pe/electron, and therefore provides a great opportunity to calibrate lxe response to lower energies than previously achieved. we will discuss recent studies to use the mix detector to perform a low energy nr calibration using thermal neutron capture in lxe with a pulsed deuterium-deuterium (d-d) neutron source. | a proposal to use mix for a low energy nuclear recoil calibration |
the coherent experiment aims to make a first detection of coherent elastic neutrino-nucleus scattering (cevns), measure the n2 dependence of its cross section, and search for new physics beyond the standard model using the few × 10 mev neutrinos from the pion decay at rest (πdar) source at the spallation neutron source (sns) at oak ridge national laboratory. a suite of four detector technologies will be deployed near the neutrino source at the sns to meet these goals. the detectors must be low-threshold and low-background in order to detect the low-energy nuclear recoils that occur from the cevns process with the sns beam neutrinos. a 14 kg csi[na] crystal detector has been running for the past year. a 185 kg nai[tl] crystal detector array was commissioned at the sns in the summer of 2016. next to be commissioned at the sns in the fall of 2016 are a 35 kg single phase liquid argon detector and a high-purity germanium detector. the performance of these detectors with regards to the cevns process will be presented. coherent collaborators are supported by the u. s. department of energy office of science, the national science foundation, nasa, and the sloan foundation. | detector technologies for the coherent experiment |
the coherent elastic neutrino nucleus-scattering has been recently detected for the first time by the coherent collaboration. it is expected that this low-energy process will be measured with more precision by the same collaboration as well as by other experimental setups. i will discuss the phenomenological impact of these measurements for physics beyond the standard model as well as for precision tests of the standard model | theoretical implications of coherent neutrino scattering |
the coherent experiment recently made the first measurement of coherent elastic neutrino nucleus scattering (cevns) at the 6.7 σ level with a 14.6 kg csi(na) crystal at the oak ridge national laboratory. coherent uses the spallation neutron source at ornl as the neutrino source and also plans to test the n ^2 dependence of the cevns cross section by making measurements on multiple targets. to that end, coherent also deploys a 22 kg fiducial mass liquid argon detector cenns-10, which was commissioned at ornl in late 2016. there have been two dedicated data runs of cenns-10, one in early 2017 and one in late 2017 after an upgrade of the light collection ability and increased shielding. i will present initial results of the first data run, a first look at the second data run, and the future plans of the coherent liquid argon program. | measuring coherent elastic neutrino nucleus scattering with the cenns-10 liquid argon detector |
prospect, the precision reactor oscillation and spectrum experiment, is a short-baseline reactor-based neutrino experiment, examining the spectrum of antineutrinos emitted by the high flux isotope reactor. antineutrinos are detected through inverse beta decay, a nuclear reaction which occurs when an electron antineutrino scatters off of a proton to produce a positron and neutron. the lithium doped liquid scintillator and optically isolated segments allow for precise event localization. as the neutron retains the direction of the antineutrino on average, prospect is in a unique position to reconstruct the direction of incoming reactor antineutrinos.directionality results from an analysis of prospect data are compared to monte carlo simulations. this talk will present a comparison of the measured average antineutrino direction to the known reactor position, and methods used to cross-check the results using background radioactivity. doe. | tracing antineutrino direction with prospect |
ge-mini is a germanium detector subsystem, part of the coherent experiment at oak ridge national lab. using stopped-pion neutrinos from the spallation neutron source, this ~16 kg array of ge detectors searches for coherent elastic neutrino-nucleus scattering (cevns) on germanium. the low threshold and ultra-low noise nature of the germanium detectors allows for further studies in nuclear physics and physics beyond the standard model, such as measures of neutron skin depth and non-standard neutrino interactions. the expected experimental sensitivity for a cevns measurement will be presented, as well as the full experimental reach for ge-mini's planned exposure and future mass upgrades. | sensitivity studies and experimental reach for ge-mini, a coherent cevns detector |
xenonnt is a dark matter direct detection experiment using a liquid xenon time projection chamber. by lowering the energy threshold to ~1 kev, it will be possible to search for the b8 solar neutrinos via coherent elastic neutrino-nucleus scattering (cevns). in this talk, i will present the background model in this search and projections for the power to discover b8 cevns with xenonnt. we gratefully acknowledge continued support for the xenon dark matter program from the national science foundation. | search for b8 solar neutrino nuclear recoil in xenonnt |
the short-baseline near detector (sbnd), a liquid argon time projection chamber (lartpc) located at fermilab will soon start accumulating data at a rate of over a million neutrino scattering events per year, initiating a wide range of neutrino physics programs. for sbnd and many other neutrino experiments, modeling neutrino-nucleus interactions provides a significant challenge. improved description of different interaction processes and nuclear effects will broadly impact cross section measurements, oscillation studies and exotic searches. this talk presents a study using monte carlo simulated data on neutrino scattering events with a muon, at least one proton, and no pions in the final state. we show how the proximity to the beam and the excellent imaging capabilities of sbnd will provide high-statistics, high-purity data on this channel, and discuss how this data could lead to a better understanding of neutrino-nucleus interactions. | studying neutrino-nucleus interactions at sbnd with muon neutrino charged-current events with protons and no pions in the final state |
the ricochet experiment aims to detect coherent elastic neutrino-nucleus scattering (cevns) at the institut laue-langevin nuclear reactor in grenoble, france. the experiment is expected to start data-taking in 2024 with two complementary detector technologies, both employing cryogenic calorimeter arrays: cryocube (germanium) and q-array (superconducting crystals). cryocube comprises 30g ge crystals instrumented with ntd-ge thermal sensors and aluminium electrodes, measuring the heat and ionization arising from particle interactions. these detectors have demonstrated a low energy threshold (~50 ev), enabling them to probe into unexplored cevns recoil energies with new physics sensitivity. meanwhile, q-array aims to lower the threshold further by developing superconducting calorimeters, exploiting the rich phonon and quasi-particle physics to gain particle identification capabilities and discriminate between electron and nuclear recoil events. this talk will highlight the first demonstration of 30 evee ionization energy resolution with ricochet germanium cryogenic bolometers and present the path towards lowering the threshold in future generations using superconducting technologies. | coherent elastic neutrino-nucleus scattering detection at a reactor with ricochet |
minerνa is a neutrino scattering experiment that uses the numi beamline with the goal of measuring neutrino-nucleus cross sections on different nuclei with high precision, as well as studying the internal structure of the nuclei of those materials. charged and neutral pion production are significant since they represent a large fraction of the events that can be seen in our detector, are highly relevant to oscillation experiments like noνa and dune, and are affected by the underlying structure of the target nuclei. i will present the current results on pion production measured by the minerva experiment using a neutrino beam of 3.6 gev, and the plans for enhancing these cross section studies on different nuclei with a higher energy neutrino beam. | charged and neutral pion production in the minerνa experiment |
the light dark matter experiment, ldmx, will scatter a 4gev monoenergetic electron beam off of a tungsten target with the goal of observing dark matter production. with an exposure of 4e14 electrons on target, we expect to see approximately 100 million electronuclear interactions. ldmx is expected to achieve excellent acceptance for the outgoing electron and hadrons in the forward region and will provide measurements that will aid in the reduction of uncertainties that arise from nuclear effects (fermi motion, binding energy, and rescattering/absorption of hadrons). the ability to make measurements of both the outoing electron and a signifcant portion of final state hadrons, including neutrons, will further constrain interaction models, which will be useful for the dune program whose phase space is very well covered by interactions in ldmx. furthermore, these interactions will span a large phase space, covering quasielastic interactions, the resonance and shallow inelastic regions, up to deep inelastic scattering. these measurements of the outgoing electron and hadron kinematics will be helpful in the modeling and understanding of neutrino oscillations. | electron-nucleus scattering at ldmx |
direct-detection experiments searching for dark matter-nucleus interactions or coherent elastic neutrino-nucleus scattering often use a charge-based readout and are commonly calibrated using sources interacting with the electrons of the detector. however, nuclear and electron interactions produce a different amount of charges for the same energy deposition. therefore, the precise knowledge of the nuclear recoil ionization yield - which quantifies the amount of energy involved in generating charge carriers for a given nuclear recoil - is essential for these science measurements. a silicon-based supercdms hvev cryogenic calorimetric detector was operated in a monochromatic neutron beam at the triangle universities nuclear laboratory (durham, north carolina) as part of the impact (ionization measurement with phonons at cryogenic temperatures) program. in this talk, we will present results from the first nuclear-recoil ionization yield measurement in silicon down to an energy of 100 ev. | first nuclear-recoil ionization-yield measurement down to 100 ev in silicon |
coherent elastic neutrino-nucleus scattering (ceνns) offers a unique way to study neutrino properties and to search for new physics beyond the standard model. the nucleus experiment aims to measure ceνns of reactor anti-neutrinos down to unprecedented low nuclear recoil energies. the novel gram-scale cryogenic detectors feature an ultra-low energy threshold of ≤20evnr and a rise time of a few 100 μs which allows the operation above ground. the fiducialization of the detectors provides an effective discrimination of ambient γ- and surface backgrounds. furthermore, the use of multiple targets promises a high physics potential. the nucleus experiment will be located at a new experimental site at the chooz nuclear power plant in france, providing a high anti-neutrino flux of $1.7\cdot {10}^{12}{\bar{\nu }}_{e}/({\rm{s}}\cdot {{\rm{cm}}}^{2})$ . the commissioning of the experimental setup with a comprehensive background measurement is planned for 2022. | exploring ceνns of reactor neutrinos with the nucleus experiment |
the next generation neutrinoless double beta (0νββ) decay experiments aim to achieve sensitive to a decay with a half-life of ~1028years. a germanium-76 (ge-76)-based experiment can achieve the discovery potential for this rare decay process due to its excellent energy resolution and ability to reject scattered gamma-ray events. legend-1000 prefers large-size detectors (>3 kg per detector) to further reduce backgrounds, complexity, and cost. this talk will explore large-size ge fabricated in a novel ring contact (gerc) geometry using high-purity ge crystals grown at usd. the gerc detector, a collaborative effort between ornl, unc, tamu, and usd, has undergone significant improvements since its inception. last year, an initial gerc detector has been successfully fabricated at tamu and subsequently tested at unc. regrettably, this first iteration did not meet our expectations. however, this presents an opportunity to enhance our research capabilities. by establishing an upgraded workshop at usd, we are now better equipped to study gerc detectors comprehensively. leveraging the invaluable experience gained from tamu, we are poised to refabricate the first detector at usd. in this presentation, we will present some preliminary results obtained from the gerc detector fabricated at usd, utilizing crystals grown exclusively at usd. this work is supported by nsf oia 2132003, nsf oise 1743790. | development of germanium (ge) ring contact detectors for ge-based neutrinoless double-beta decay experiment |
neutrinos elastically scattering off atomic electrons is a purely leptonic process whose cross section can be precisely calculated in the standard model. a measurement of this process can provide an in-situ constraint to the absolute neutrino flux in an accelerator-based nμ beam. nova is a long-baseline neutrino experiment optimized to observe the oscillation of muon neutrinos to electron neutrinos. it consists of a near detector located 1 km downstream of the neutrino production target at fermilab and a far detector located 810 km away in ash river, minnesota. this talk presents the status of the neutrino-electron elastic scattering measurement, including strategies of selecting signals, as well as the prospect of reducing the flux uncertainty. | status of the measurement of neutrinos elastically scattering off electrons in the nova near detector |
understanding the origin of quark confinement in hadrons remains one of the most challenging problems in modern physics. recently, the pressure distribution inside the proton was measured via deeply virtual compton scattering. surprisingly, strong repulsive pressure up to 1035 pascals, the highest so far measured in our universe, was obtained near the center of the proton up to 0.6 fm, combined with strong binding energy at larger distances. we show here that this profile can be derived semiquantitatively without any adjustable parameters using the rotating lepton model of composite particles (rlm), i.e. a proton structure comprising a ring of three gravitationally attracting rotating ultrarelativistic quarks. the rlm synthesizes newton's gravitational law, einstein's special relativity, and the de broglie's wavelength expression, thereby conforming with quantum mechanics, and also yields a simple analytical formula for the proton radius and for the maximum measured pressure which are in excellent agreement with the experimental values. | proton internal pressure distribution suggests a simple proton structure |
an important aspect of rare event nuclear physics research such as neutrinoless double beta (0νββ) decay is filtering out background events that can lower data resolution. the search for 0νββ decay of 136xe utilizes enriched 136xe but still contains significant amounts of 134xe. this poses a problem because, despite many experiments taking place in underground facilities, neutron-induced reactions can still occur in the sample and interfere with the data collected. two background processes of interest are neutron inelastic scattering and neutron capture in 134xe. the resultant de-excitation gamma rays from neutron inelastic scattering of 134xe can scatter into the region of interest for 136xe neutrinoless double beta decay. at triangle universities nuclear laboratory, we have measured neutron inelastic scattering and neutron capture on 134xe. to fully understand the results of this experiment, we need to know the self absorption (a measure of the percentage of gamma rays that deposit energy in a sample) of the 134xe sample. we simulated the absorption in a sample of 134xe using gears and geant 4 along with the root data analysis package to directly get the absorption number for use in data analysis. we will report this absorption number for various gamma ray energies of interest. tennessee technological university creative inquiry summer experience. | simulating self absoption in 134 xenon for neutrinoless double beta decay research |
the coherent collaboration operates a suite of detectors at the spallation neutron source (sns), at oak ridge national laboratory. these detectors, located in a narrow undergound hallway, are designed to measure and search for neutrino, neutron and dark matter interactions from the sns source. in 2017, the collaboraiton produced the first measurement of coherent elastic neutrino-nucleus scattering (cevns) on a small 14 kg csi[na] crystal scintillator, followed two years later by the second measurement of cevns using liquid argon. the collaboration has also recently put strong constraints on the charged-current inelastic neutrino-lead cross section, and measured the inclusive charged-current neutrino cross section on i-127. i will briefly discuss the current status of the cevns and inelastic measurement programs, and their uses for studying neutrino properties and neutrino-nucleus interactions. i will also discuss future plans for the detector suite, including measurements on sodium, thorium, deuterium, along with ongoing work to ton-scale detector systems. | the coherent experimental program: an update |
elastic scattering of neutrino with nucleus (v ael ) is the well defined weak interaction processes in the standard model. the texono collaboration adopt electro-cooled point contact germanium detector technology with sub-kev sensitivities for the detection of v ael with reactor neutrinos. the detection of v ael cross-section is beneficial in studies of irreducible background in dark matter experiments, study of solar and supernova processes, etc. it also provides the probe the quantum mechanical coherence effects in electroweak interactions. we defined a parameter α to measure degree of coherency in v ael . reactor neutrinos are found to be one of the best candidates to probe v ael with high coherency. the divergence from full coherence leads to the study of neutron density distribution and to constrain the sensitivities in probing physics beyond the standard model. | coherency in neutrino-nucleus elastic scattering |
the idea of measuring the coherent elastic nuclear scattering of neutrinos emitted by a high intensity 51cr radioactive source is investigated. to produce the high intensity source, the radioactive material used in the gallex experiment (36 kg of chromium 38.6% enriched in 50cr) could be reactivated to an intensity of few mci. the advantages of this source are that the activity can be measured at few per mill level and that the neutrino spectrum is well known. with a target volume of 2 dm3 of low-threshold detectors, if the background is limited, the crosssection might be measured with few percent precision. in this work the requirements for the experiment will be shown and the envisioned experimental challenges will also be discussed. | measuring the coherent elastic neutrino-nucleus scattering with an high intensity 51cr radioactive source |
coherent captain-mills(ccm) experiment is a 10 ton liquid argon scintillation detector experiment located at the los alamos national laboratory(lanl). the los alamos neutron science center(lansce) provides an 800 mev proton beam on a tungsten target which is a copious source of neutrinos from stopped pions, as well as, possibly, new particles belonging to dark sector of particle physics with masses in the range of kev to mev. this sub-gev dark matter then coherently scatters off the ar nuclei to produces scintillation light. the ccm detector is equipped with photomultiplier tubes(pmts) to capture the scintillation light. a prototype detector instrumented with 120 pmts, ccm120 operated between 2018 and 2019, demonstrating the potential of such a detector for the search of sub-gev dark matter. ccm's first engineering run has already achieved sensitivity to previously unexplored parameter space of light dark matter (ldm) models with a baryonic vector portal. the upgraded ccm200 detector, with 200 pmts, improved shielding and lar filtration and purification system is now taking beam data. in this talk the status of the experiment, as well as results from ccm120 and expected sensitivity to new physics of ccm200 will be presented. | dark matter searches at coherent captain-mills |
i will present the anatomy of production mechanisms for sterile neutrino dark matter in the presence of new interactions among either active or sterile neutrinos. these new interactions can be mediated by a scalar or a vector, and allow sterile neutrinos to make up all the dark matter while safely evading all current experimental bounds. we identify three regimes of the mediator's mass and coupling where it makes a distinct impact on dark matter production through the dispersion relations and/or scattering rates. these models serve as a well-motivated target for the upcoming experimental searches. the work of wt is research is currently supported by the national science foundation under grant no. phy-2013052. | sterile neutrino dark matter via secret neutrino interactions |
this talk will cover new ideas to search for physics beyond the standard model with accelerator neutrino beams in the intermediate energy range. i will review searches for heavy neutral leptons, dark photons, and light scalars using decay-in-flight and neutrino-scattering signatures. i will review several models proposed to explain anomalies in accelerator experiments, focusing on dark sector models and their interplay with other intensity frontier experiments. i will then conclude with the prospect of their discovery at current and future facilities. the research at the perimeter institute is supported in part by the government of canada through nserc and by the province of ontario through the ministry of economic development, job creation and trade, medt. | neutrino portals to beyond standard model physics: from 100 mev to 100 gev |
the 3he(α,γ)7be fusion reaction is an important part of ongoing processes occuring in stars like our very own sun. this fusion reaction is key to determining the 7be and 8b neutrino fluxes resulting from the pp-ii chain in the sun . in standard solar model (ssm) predictions of these neutrino fluxes, the low-energy 3he(α,γ)7be s factor, s34(e), is the largest source of uncertainty from nuclear input. the ssm uses s34(e) near the gamow peak energy, roughly 18 kev, which cannot be experimentally measured since the coulomb force between 3he and 4he suppresses the fusion reaction at such low energies. theoretical calculations are needed to guide the extrapolation to the solar energies of interest. to this end, i will present ab initio calculations of the 3he(α,γ)7be reaction using the no-core shell model with continuum starting from two- and three-nucleon chiral interactions. to demonstrate that the ncsmc provides an accurate s factor, i will also compare ncsmc 3he + 4he elastic-scattering cross sections with those recently measured by the sonik collaboration. this work was performed under the auspices of the u.s. department of energy by lawrence livermore national laboratory under contract de-ac52-07na27344. lawrence livermore national security, llc. | ab initio investigations of helium fusion |
future neutrino observatories, like the deep underground neutrino experiment (dune), will be sensitive to supernovae and solar neutrinos of low energies. these neutrinos offer a unique look inside stars and stellar explosions. inside the dune liquid argon time projection chamber, low-energy electron neutrinos will produce visible electrons. in this talk, we will present a preliminary study of delta-rays that have similar energies to the electrons scattered by low-energy astrophysical neutrinos. unlike neutrinos, delta-rays are a well understood ''standard candle.'' furthermore, they provide ample statistics, a valuable feature in the otherwise quiet underground environment. we will outline how they can be used to calibrate dune's response to < 30 mev electrons in situ. | delta rays: a novel calibration for the deep underground neutrino experiment (dune) for low energy astrophysical neutrinos |
a thorough understanding of neutrino-nucleus interactions physics is crucial to achieving precision goals in broader neutrino physics programs. the complexity of nuclei comprising the detectors and limited understanding of their weak response constitutes one of the biggest systematic uncertainties in neutrino experiments - both at intermediate energies affecting the short- and long-baseline neutrino programs as well as at lower energies affecting coherent scattering neutrino programs. while electron and neutrino interactions are different at the primary vertex, many underlying relevant physical processes in the nucleus are the same in both cases, and electron scattering data collected with precisely controlled kinematics, large statistics and high precision allows one to constrain nuclear properties and specific interaction processes. to this end, electron-nucleus scattering experiments provide vital complementary information to test, assess and validate different nuclear models and event generators intended to be used in neutrino experiments. in fact, for many decades, the study of electron scattering off a nucleus has been used as a tool to probe the properties of that nucleus and its electromagnetic response. while previously existing electron scattering data provide important information, new and proposed measurements are tied closely to what is required for the neutrino program in terms of expanding kinematic reach, the addition of relevant nuclei and information on the final states hadronic system. | potential constraints to neutrino-nucleus interactions based on electron scattering data |
in the work arguments are provided in favor of using tritium as an (anti)neutrino source in experiments on research of neutrino electromagnetic properties. it is described the evolution of the tritium (anti)neutrino source design with the intensity of 40 mci with respect to experiments on defining the neutrino magnetic moment. the physical experiment particulars are discussed with account for physical, chemical and radiational properties of tritium. in continuation of work [1] on the research of neutrino coherent scattering at atoms and nuclei of liquid helium present in the superfluid state, as well as and on the research of neutrino electromagnetic properties, it is proposed using a tritium source with the intensity of 10 mci. specifics of such experiments are discussed. | highly intensive antineutrino tritium source: specifics of physical experiment |
next-generation neutrino oscillation experiments will require precise knowledge of neutrino-nucleus cross sections to achieve precise measurements of neutrino oscillation parameters. lattice qcd can be used to calculate nuclear matrix elements relevant for describing electroweak interactions across a range of energies. i will discuss recent progress in lattice qcd calculations of the energy spectrum and matrix elements of light nuclei, in particular variational methods for controlling important systematic uncertainties arising from excited-state effects. | towards lattice qcd inputs for neutrino-nucleus scattering |
precision measurements of coherent elastic neutrino-nucleus scattering (cevns) will allow a broad collection of physics studies ranging from improving constraints on non-standard neutrino interactions to probing nuclear structure. following initial cevns measurements on csi and ar, the coherent experiment is entering an era of precision measurements. current coherent measurements are limited by the 10 % uncertainty on the neutrino flux from the pion decay-at-rest neutrino source at the oak ridge national laboratory spallation neutron source (sns). to reduce this uncertainty, a 592 kg heavy-water demonstrator has been designed to measure the absolute neutrino flux from the sns making use of the well-understood d +νe cross section. the first of a planned 2-detector module, the demonstrator will measure the neutrino flux with better than 5 % statistical precision in 2 sns-years of running. in this talk i will present the d2o detector design and discuss the expanded physics sensitivity of cevns detectors at the sns with an improved understanding of the neutrino flux. this work is supported by the u.s. department of energy, office of science, office of high energy physics and the national science foundation office of nuclear physics. this research also used resources at the spallation neutron source, which is a doe office of science user facility operated by the oak ridge national laboratory. | design of a d2o detector for flux normalization at a pion decay-at-rest neutrino source |
studies on neutrino-nucleon ($\nu n$) cross sections at different energy scales have regained interest due to increasing importance of precision measurements, as they are needed as an ingredient in all neutrino experiments. in this paper we have calculated both charged current (cc) and neutral current (nc) $\nu$n scattering cross sections at ultra high energy (uhe) regime in the neutrino energy ($e_{\nu}$) region i.e. $10^{9} gev \le e_{\nu} \le 10^{12}$ gev using qcd inspired double asymptotic limit fit of electron-proton structure function $f_{2}^{ep}$ to low $\mathit{x}$ hera data. the form $f_{2}^{ep} \sim x^{-\lambda(q^{2})}$ used in our analysis, can be conjectured like a dynamic pomeron (dp)-type behaviour. we also find an analytic form of the total cross sections, $\sigma_{cc}^{\nu n}$ and $\sigma_{nc}^{\nu n}$ which appear to be of hard-pomeron exchange types. a comparative analysis of our results with those available in literature is also done. an improved understanding of $\nu n$ interactions at uhe are essentially important for future oscillation experiments. future measurements will support/confront our predictions. \textbf{keywords}: neutrino cross section, ultra high energy, qcd, double asymptotic limit, dynamic pomeron, hard-pomeron. | pomeron inspired neutrino-nucleon cross section in ultra high energy |
the rate of neutrinoless double-beta decay (0 νββ) depends on three components: the phase-space factor for the emission of two electrons, the effective majorana mass of the electron neutrino, and the nuclear matrix element (nme). the nmes cannot be measured experimentally and must be calculated. various nuclear structure models have been used for this purpose including the shell model, interacting boson model, quasiparticle random phase approximation, and energy density functional theory, the results of which differ by factors of 2-3 for individual nuclei. increasing the accuracy of and reducing the uncertainty in the nmes is considered crucial for extracting the neutrino mass if the half-life of 0 νββ is measured. to test these calculations and constrain the models, theoretical results are compared with nuclear structure data for reproducibility. data of importance include level energies, spins and parities, branching ratios, mixing ratios, and transition probabilities. while the structure of the double-beta decay parent and daughter are paramount, many of these nuclei lie in complex regions of nuclear structure and it is necessary to understand the properties of other nuclei in the isotopic chain as well in order to fully characterize the structures involved. unfortunately, systematic data are not always available to test the models. while improvements in our knowledge of the structure of many 0 νββ candidates are ongoing, the ge nuclei have been the focus of numerous recent studies. various experimental techniques including coulomb excitation, photon scattering, inelastic neutron scattering, beta decay, and others have been employed to study 76ge (the 0 νββ candidate) and other nuclei in the isotopic chain. in this presentation, i will describe recent experimental advances in this region as well as the results of model calculations for comparison. this material is based in part upon work supported by the u.s. national science foundation under grant no. phy-1913028. | nuclear structure for neutrinoless double-beta decay |
the coherent collaboration operates an array of detectors at the ornl spallation neutron source (sns) to measure coherent elastic neutrino nucleus scattering (cevns) and to search for dark matter. the 1.4 mw sns pulsed proton beam produces an intense neutrino flux and may be producing dark matter particles. our low-energy-threshould detectors sited in the low-background `neutrino alley' near this source are producing world-leading sensitivity for these measurements. we observed the first events from cevns in 2017 with a cesium-iodide scintillation detector and have new results from an expanded data set. we followed up with a measurement, published in 2020 on a lighter argon nucleus confirming the cevns hypothesis. these data sets can also be used to search for dark matter as predicted in a class of portal-particle dark matter theories and our recent cesium-iodide results elimate some parameter-space required to explain cosmologically observed dark-matter. these measurements will be presented along with plans for further extending our physics reach with new detectors in the near future. the coherent collaboration acknowledges the generous resources provided by the ornl spallation neutron source, a doe office of science user facility.we also acknowledge support from the alfred p. sloan foundation, the consortium for nonproliferationenabling capabilities, the institute for basic science, the national science foundation. | studies of neutrino interactions and dark matter with the coherent experiment |
the sun -- due to its high matter density, and abundant hydrogen content -- is an excellent target for studying spin dependent dark matter-proton scattering. the sun can gravitationally trap weakly interacting massive particles (wimps) from the galactic halo, which then thermalize in the solar core. the captured dark matter (dm) in the sun can annihilate into standard model particles including an observable flux of neutrinos. the icecube neutrino observatory with its optimal sensitivity to tev--pev neutrinos has performed several analyses constraining the spin-dependent dm-proton cross-section more than an order of magnitude stronger than direct detection experiments. however, the parameter space with dm masses below 50 gev has remained uncharted territory for icecube. this work for the first time utilizes special cuts and includes ``starting events'' to extend icecube's sensitivity to wimp masses down to 5 gev. we present the results of a search for low-energy (<300 gev) neutrinos correlated with the direction of the sun using 7 years of icecube data. our observations exclude dm-proton scattering down to a few times 10-42 cm2 for the nu-nu channel at 20 gev, which are the world's strongest constraints at these energies for dm annihilation directly to neutrinos. icecube collaboration, nsf grant phy-1913607. | search for sub-tev wimp-annihilation in the sun |
cryogenic calorimeters have established themselves as one of the primary technologies for rare event search experiments with applications from neutrinoless double beta decay, dark matter search to the novel field of precision measurements of the coherent elastic neutrino nucleus scattering ce??ns cross-sections. in this talk we will discuss the development and testing of a novel self-contained low tc tes readout chip for application in the search for ce??ns with 40 g-scale absorbers in the ricochet experiment, next generation cevns searches and for 0nbb-search applications in the cupid program. the low impedance, fast response and existing multiplexing technologies make tes sensors very desirable in particular for future large-scale detector arrays as they can be mass produced with semiconductor technology and allow for scalable readouts. the chips can be readily connected to various absorbers via a deposited au film as phonon collector on the target. we will present performance predictions from the thermal modeling of these devices with respect to the cevns program and the status of our detector fabrication and testing. this work is supported by the us doe office of nuclear physics, the us nsf, and internal investments at all institutions. | design of low tc tes chips as sensors for low background calorimeter arrays in neutrino physics |
as neutrinoless double-beta decay searches seek to reach into and beyond the inverted hierarchy regime, new strategies are needed to reject background events in kiloton-scale detectors. in monolithic liquid-scintillator-based detectors, otherwise-irreducible backgrounds like 8b solar neutrino scattering could be identified by their event topology using cherenkov light signals. nudot is a half-ton prototype that aims to demonstrate this technique with 1 to 2 mev beta particles, using precision timing to distinguish the cherenkov and scintillation signals. following a successful demonstration of the separation technique in the flatdot test-stand, the nudot detector was built at bates research and engineering center. preliminary results from the commissioning phase of the experiment will be shown. in the coming months, we will continue to conduct surface measurements demonstrating direction reconstruction of calibration source beta events. following this phase of operation, nudot will undergo upgrades and continue in an additional surface operation phase at triangle universities nuclear laboratory, followed by an underground measurement of two-neutrino double-beta decay with direction reconstruction. nudot is supported by nsf award numbers 1554875 and 1806440. | new results from nudot: double-beta decay with direction reconstruction in liquid scintillator |
the coherent collaboration recently completed the first year of operation at the spallation neutron source (sns) with a 14 kg csi detector optimized for coherent elastic neutrino nuclear scattering (cevns) sensitivity. the oak ridge national laboratory is now converting a service corridor only 20 meters from the sns target into a dedicated neutrino laboratory. by the fall of 2016, the collaboration will deploy three additional targets to measure the cevns cross section dependence on the target nuclei neutron number with targets ranging from argon to cesium for an unambiguous first observation. the status of the csi data analysis and related background evaluations will be presented and the details of the anticipated detector performance for all four targets will be reported. beyond these proof-of-principle cevns measurements, the intensity, pulse-structure, and beam-energy make the spallation neutron source ideally suited for a set of high-precision measurements using more massive, purpose-built detectors to address a host of physics topics including searches for non-standard neutrino interactions and a measurement of the weak mixing angle. the broader impact of a larger scale coherent program will be outlined. | the coherent experiment: overview and update of results |
supercdms snolab is a low-background experiment that will use semiconductor germanium and silicon detectors to search for galactic dark matter. in addition the experiment has potential to measure the coherent scattering of solar 8b neutrinos. this process will dominate some parts of the spectrum between 1 and 10 kev in the detectors with full background rejection capabilities. however the total number of events from coherent neutrino scattering is expected to be ∼1 if the experiment is assumed to operate five years with an 80% live time, and therefore not sufficient to provide a significant observation of this process. upgrades to the experiment are planned to extend the sensitivity down to the limit set by the coherent neutrino scattering. | supercdms snolab: status and prospects for measuring the coherent neutrino scattering |
we have reviewed the current status of the inclusive neutrino scattering from $^{12}$c in the low energy region corresponding to the neutrino beams from the pion, muon and kaon decaying at rest. the theoretical calculations of total cross sections in various nuclear models with special emphasis on the recent experiments with the monoenergetic neutrinos from kdar [1] along with the older experiments from karmen and lsnd collaborations have been discussed in the context of the recent works by akbar et al. [2] and nikolakopoulos et al. [3]. the inadequacy of the various theoretical models used to explain the experimental results on the inclusive neutrino scattering from nuclei at low energies has been highlighted and the need for a better understanding of the nuclear medium effects beyond the impulse approximation has been emphasized. | the low energy inclusive $\\nu_{\\mu} (\\nu_{e})-^{12}$c scattering revisited |
the analysis of pion production in neutrino-nucleus scattering is crucial to quantify the effect of final state interactions (fsi) in the energy regime of dune and other long-baseline neutrino experiments since fsi modify the number of pions that emerge in the final state as compared to the number of pions produced in the initial (primary) state. not only the number of pions but also their charge gets changed due to the prevailing fsi effects. in the present work, we will study the effect of fsi on pions after their production at the initial neutrino-nucleus interaction vertex using two different monte carlo (mc) simulation tools viz. genie (version: 3.0.6) and nuwro (version: 19.2.2). considering the dune experimental set-up, we observe pion production in νµ and 40 ar nucleus interactions for an event sample of 1 million for each generator. we find that there are some differences in the pion number observed in the primary and final states of two generators and that the differences are above statistical fluctuations. we observe that genie (version: 3.0.6) is more responsive (less transparent) to absorption and charge exchange processes as compared to nuwro (version: 19.2.2). | quantifying effects of final state interactions on pion production in dune using monte carlo event generators |
symanzik's approach to the description of quantum field systems in an inhomogeneous space-time is used to construct a model for the interaction of neutrino fields with matter. in this way, the problem of the influence of strong inhomogeneities of the medium on the processes of oscillations is considered. as a simple example, a model of neutrino scattering on a material plane is investigated. within this model, in the collisions of particles with planes, a special filtration mechanism can be formed. it has a significant impact on the dynamics of subsequent neutrino oscillations which are analogous to the mikheev-smirnov-wolfenstein effect at propagation of these particles in an adiabatic medium. taking into account the possibility of the filtration process in a highly inhomogeneous environment can be useful in planning and carrying out experimental studies of neutrino physics. it can also be considered by investigations of the role of neutrino in astrophysical processes by means of numerical simulations methods. | neutrino oscillations in the model of interaction of spinor fields with zero-range potential concentrated on a plane |
we study indirect detection signals from solar annihilation of dark matter (dm) particles into light right-handed (rh) neutrinos with a mass in the 1 - 5 gev range. these rh neutrinos can have a sufficiently long lifetime to allow them to decay outside the sun and their delayed decays can result in a signal in gamma rays from the otherwise `dark' solar direction, as well as a neutrino signal that is not suppressed by the interactions with solar medium. we show that the latest fermi-lat and icecube results place limits on these gamma ray and neutrino signals, respectively, and the combined bounds can constrain the spin-independent dm-nucleon elastic scattering cross section better than direct detection experiments for dm masses from 200 gev up to several tev. the bounds on spin-dependent scattering cross section are also much tighter than the strongest limits from direct detection experiments. | probing dark matter annihilaiton to right-handed neutrinos |
the problem of detection of recoil electrons from neutrino scattering at low energies is considered. the use of the spectrum of an antineutrino tritium source (${}3$h) with a small boundary energy of 18.6 kev is of interest for searches for the neutrino magnetic moment. at small neutrino energies, the electron binding energy in an atom becomes important. the cross sections for electrons of cs, i, and si atoms as possible targets in an experiment with a tritium source are calculated. | inclusion of electron binding in atomic shells in calculation of cross sections for magnetic and weak neutrino-electron scattering |
different constraints to the neutrino electric millicharge (nem) have been obtained by considering interactions such as the elastic neutrino-electron scattering (enes). however, the great potential of the coherent elastic neutrino-nucleus scattering (ce$ν$ns) in future reactor neutrino experiments could be an alternative to improve the current limits on the nem. in this work we study the sensitivity of enes and ce$ν$ns interactions in reactor experiments to the neutrino charge through a combination of different experimental data. bounds up to the order of $10^{-14}e$ are achieved from ce$ν$ns at reactor neutrino experiments. | sensitivity to the neutrino electric millicharge of experiments involving elastic neutrino-electron and coherent elastic neutrino-nucleus processes |
in this session we focused on the higher energy deep and shallow inelastic particle interactions, dis and sis. dis interactions occur when the energy of the incident particle beam is so large that the beam is able to penetrate the nucleons inside of the target nuclei. these interactions occur at the smallest level possible, that of the quark-gluon, or parton, level. sis interactions occur in an intermediate energy range, just below the energy required for dis interactions. the dis cross section formula contains structure functions that describe our understanding of the underlying parton structure of nature. the full description of dis interactions requires three structure functions: two may be measured in charged lepton or neutrino scattering, but one can only be extracted from neutrino dis data. there are reasons to expect that the impact of nuclear effects could be different for neutrinos engaging in the dis interaction, vs those felt by leptons. in fact, fits by the ncteq collaboration have found that the neutrino-fe structure functions appear to differ from those extracted from lepton scattering data [1]. to better understand the global picture of dis and sis, we chose a three-pronged attack that examined recent experimental results, data fits, and latest theory predictions. experimental results from neutrino and lepton scattering, as well as collider experiments, were presented. | deep and shallow inelastic scattering |
the γ-ray production cross section for the 477.6-kev transition in 7li following inelastic neutron scattering has been measured from the reaction threshold up to 18 mev. this cross section is interesting as a possible standard for other inelastic scattering measurements. the experiment was conducted at the geel electron linear accelerator (gelina) pulsed white neutron source with the gamma array for inelastic neutron scattering (gains) spectrometer. previous measurements of this cross section are reviewed and compared with our results. recently, this cross section has also been calculated using the continuum discretized coupled-channels (cdcc) method. experiments for studying neutrinoless double-β decay (2β0ν) or other very rare processes require greatly reducing the background radiation level (both intrinsic and external). copper is a common shielding and structural material, used extensively in experiments such as cobra, cuore, exo, gerda, and majorana. understanding the background contribution arising from neutron interactions in cu is important when searching for very weak experimental signals. neutron inelastic scattering on natcu was investigated with gains. the results are compared with previous experimental data and evaluated nuclear data libraries. | inelastic neutron scattering cross-section measurements on 7li and 63,65cu |
we review some recent progress in the study of electroweak interactions in nuclei within the susav2-mec model. the model has the capability to predict (anti)neutrino scattering observables on different nuclei. the theoretical predictions are compared with the recent t2k $\nu_\mu-^{16}$o data and good agreement is found at all kinematics. the results are very similar to those obtained for $\nu_\mu-^{12}$c scattering, except at low energies, where some differences emerge. the role of meson-exchange currents in the two-particle two-hole channel is analyzed in some detail. in particular it is shown that the density dependence of these contributions is different from what is found for the quasielastic response. | meson-exchange currents and quasielastic predictions for neutrino-nucleus scattering |
the accelerator neutrino neutron interaction experiment (annie) at fermilab will use 30 tons of gadolinium-enhanced water to capture and detect the otherwise invisible neutrons produced in complex neutrino-nucleus interactions in addition to traditional water-cherenkov charged particle detection. the number of these final-state neutrons helps constrain the interaction type and the kinematics of the target nucleus, which are major sources of uncertainty in event reconstruction and simulation. the recently completed phase i measured background neutrons associated with the neutrino beam, including "dirt neutrons" from neutrino interactions outside the detector and "skyshine neutrons" from the beam which scatter into the experimental hall. phase i used pure water with a movable instrumented vessel of gadolinium-loaded liquid scintillator to measure the neutron flux at various locations within the tank. this poster will discuss the annie detector and present the phase i results. | the annie experiment - results from phase i |
quark-hadron duality connects the resonance and deep inelastic scattering (dis) region in the intermediate energy regime of electron-proton (ep) scattering. resonances include the δ(1232) and other heavier nucleon resonances peaking at higher hadron invariant mass w (~ 1 . 4 - 2 . 0 gev), a kinematic region which needs study to better understand the transition between a hadronic resonance description and a perturbative qcd description of ep inelastic scattering. we present results for the structure function f2(x ,q2) and f1(x ,q2) for electron-proton inelastic scattering including nonperturbative and higher order perturbative qcd effects. with theoretically motivated extrapolations to low momentum transfers, we compare our results with parametrized structure functions and jlab data for inclusive ep scattering. a better understanding of quark-hadron duality in ep scattering will have implications for neutrino-nucleon/nucleus scattering, important for the neutrino experiments like no νa, miner νa and dune which have significant numbers of events in this less explored transition region. work supported in part by the us doe. | theoretical and phenomenological understanding of quark-hadron duality |
we explore the implications of recent nucleon axial form factor lattice calculations for neutrino scattering experiments. national science foundation (phy 1714253). | exploring the functional dependence of the nucleon axial form factor |
microboone is a liquid argon time projection chamber that operates in the booster neutrino beam at fermilab. the detector provides high-resolution imaging of neutrino interactions with a low threshold and full angular coverage. thanks to a high event rate and several years of continuous operation, the microboone collaboration has obtained the world's largest dataset of neutrino-argon scattering events. a detailed understanding of these interactions, especially the impact of nuclear physics effects, will be critical to the success of future precision neutrino oscillation efforts, particularly the argon-based deep underground neutrino experiment (dune) and the short-baseline neutrino (sbn) program. this talk presents an overview of the latest neutrino-argon cross section measurements in microboone, including measurements of protons produced in muon neutrino interactions, measurements of the electron neutrino inclusive cross section, and progress towards measurements of rare channels. | recent neutrino cross-section results from microboone |
the coherent collaboration is aimed at measuring coherent elastic neutrino-nucleus scattering (cevns) with high-quality pion-decay-at-rest neutrinos from the spallation neutron source (sns) at oak ridge national lab (ornl), tennessee. neutrons that survive thick shielding between the source and coherent detectors are a serious background for cevns detection. a dedicated neutron detector, mars, is used to measure this background. the performance of this detector has been characterized using various radioactive sources, including a dt neutron generator. a geant4 monte carlo simulation package has been developed to evaluate the efficiency of neutron detection and to understand the detector response to neutrons at various energies. reported here are the comparison of the recorded and simulated calibration data, as well as the simulated neutron detection efficiency. the efficiency is used to estimate the neutron background level of coherent detectors. | monte carlo simulation of a dedicated neutron detector for the coherent experiment at the sns, ornl |
we consider the impact of the recent data obtained by the lhc, tevatron, and fixed-target experiments on the nucleon quark distributions with a particular focus on disentangling different quark species. an improved determination of the poorly known strange sea distribution is obtained due to including data from the neutrino-induced deep-inelastic scattering experiments nomad and chorus. the impact of the associated (w + c) production data by cms and atlas on the strange sea determination is also studied and a comparison with earlier results based on the collider data is discussed. finally, the recent lhc and tevatron data on the charged lepton asymmetry are compared to the nnlo abm predictions and the potential of this input in improving the non-strange sea distributions is evaluated. | nucleon pdf separation with the collider and fixed-target data |
experimental investigations of neutrino properties, using neutrino beams generated at accelerators facilities, necessitate a detailed and precise knowledge of neutrinonucleus reaction mechanisms. in the energy region of nuclear quasi-elastic scattering, pion-production reactions constitute an important background process. a theoretical understanding of these processes is then required in order to correctly determine the produced neutrino energy spectrum. in the first stage of our research project, we study neutrino induced pion-production off deuterons. the choice of the deuteron minimizes the complications of the nuclear dynamics associated with larger nuclear systems. we evaluate the pion-production reaction near threshold using heavy baryon chiral perturbation theory. | neutrino pion production off deuteron |
the spherical proportional counter is a novel type of radiation detector, with a low energy threshold (typically below 100 ev) and good energy resolution. this detector is being developed by the network news, which includes several applications. we can name between many others dark matter searches, low level radon and neutron counting or low energy neutrino detection from supernovas or nuclear reactors via neutrino-nucleus elastic scattering. in this context, this works will present the characterization of a spherical detector of 1 meter diameter using two argon-based mixtures (with methane and isobutane) and for gas pressures between 50 and 1250 mbar. in each case, the energy resolution shows its best value in a wide range of gains, limited by the ballistic effect at low gains and by ion-backflow at high gains. moreover, the best energy resolution shows a degradation with pressure. these effects will be discussed in terms of gas avalanche properties. finally, the effect of an electrical field corrector in the homogenity of the gain and the energy threshold measured in our setup will be also discussed. | characterization of a spherical proportional counter in argon-based mixtures |
the new general-purpose fixed target experiment ship (search for hidden particles) at the cern sps (super proton synchrotron) is aimed at research in the field of beyond standard model (bsm) physics and of tau-neutrino physics. the emulsion neutrino detector will be one of the main elements in the ship detector design. it is intended for search for dark matter scattering on electrons of nuclear emulsion and for tau-neutrino and anti tau-neutrino direct observation, and study their properties and the cross section. the main source of both hidden particle and tau-neutrino event fluxes is the decay of charmed particles produced in the ship proton target. the detection of the production and decay of charmed hadrons in the target will be performed through nuclear emulsion films employed in the emulsion cloud chamber target structure. the paper describes the basic principles of the ship neutrino emulsion detector and some measures for its optimization. | emulsion detector for future experiment ship at cern |
linear alkylbenzene (lab) based liquid scintillator is adopted as the central detector for the jiangmen underground neutrino observatory (juno) liquid scintillator detectors. a quenching factor measurement instrument is designed based on the compton scattering process. two different quenchers for the liquid scintillator have been investigated and the result shows that the scintillation light of the juno liquid scintillator can be quenched to a level. the emission spectrum with the absence of the quencher is also showing a desired behavior. | quenching of fluorescence for linear alkylbenzene |
here we present analysis results from the minerva experiment for scattering of neutrinos on nucleus in an energy region of few gev. these results cover a plethora of processes important for high precision neutrino oscillation measurements in which recent results have suggested that the currently used models are insufficient. | neutrino interactions on nuclei at minerva |
we review the recent progress in modelling neutrino-nucleus scattering, in a framework based on scaling which describes simultaneously the nuclear response to electromagnetic and weak probes. the study is relevant for the analysis of neutrino oscillation data and the design of the next generation experiments hyper-kamiokande and dune. | a model for neutrino-nucleus interactions in the gev region |
the reactor antineutrino and the gallium anomalies have been long unexplained. possible explanations for both of these anomalies include new physics, such as the existence of one or more ev-scale sterile neutrino. however, the previous theoretical calculations, which do not replicate the experimental results, rely on many simplifying approximations. we have performed shell model calculations in order to gain insights into these issues. in the reactor-antineutrino analysis the beta decays contributing to the cumulative electron spectrum are usually assumed to have allowed spectral shapes. however, many of these decays are actually first-forbidden. moreover, these decays dominate the experimentally observable region. based on the recent results, the use of this allowed approximation can at least partially explain the so called reactor antineurtino anomaly. our new large-scale shell model calculations regarding the neutrino-nucleus scattering cross section off 71ga decreases the gap between theory and the experimental results of gallex and sage experiments. conflict between charge-exchange bgts and the neutrino-nucleus cross sections can to some extent be explained by destructive interference between gamow-teller and tensor contributions. | anomalies and sterile neutrinos - implications of new theoretical results |
we present results of our recent epps16 global analysis of nlo nuclear parton distribution functions (npdfs). for the first time, dijet and heavy gauge boson production data from lhc proton-lead collisions have been included in a global fit. especially, the cms dijets play an important role in constraining the nuclear effects in gluon distributions. with the inclusion of also neutrino-nucleus deeply-inelastic scattering and pion-nucleus drell-yan data and a proper treatment of isospin-corrected data, we were able to free the flavor dependence of the valence and sea quark nuclear modifications for the first time. this gives us less biased, yet larger, flavor by flavor uncertainty estimates. the epps16 analysis indicates no tension between the data sets used, which supports the validity of collinear factorization and universal npdfs for nuclear hard-collision processes in the kinematical range studied. | epps16 - first nuclear pdfs to include lhc data |
we present the projected sensitivity of the lux-zeplin (lz) dark matter experiment to solar boron-8 neutrinos detected via coherent elastic neutrino-nucleus scattering, and the physics prospects opened by such a measurement with the lz detector. | solar boron-8 neutrino detection with the lz dark matter experiment |
darwin (dark matter wimp search with liquid xenon) will be a multi-ton dark matter detector with the primary goal of exploring the entire experimentally accessible parameter space for weakly interacting massive particles (wimps) over a wide mass-range. with its 40 tonne active liquid xenon target, low-energy threshold and ultra-low background level, darwin can also search for other rare interactions. here we present its sensitivity to low-energy solar neutrinos and to neutrinoless double beta decay. in a low-energy window of 2-30 kev a rate of 105/year, from pp and 7be neutrinos can be reached. such a measurement, with 1% precision will allow testing neutrinos models. darwin could also reach a competitive half-life sensitivity of 8.5 · 1027 y to the neutrinoless double beta decay (0νββ) of 136xe after an exposure of 140 t×y of natural xenon. nuclear recoils from coherent scattering of solar neutrinos will limit the sensitivity to wimp masses below 5 gev/c2, and the event rate from 8b neutrinos would range from a few to a few tens of events per tonne and year, depending on the energy threshold of the detector. deviations from the predicted but yet unmeasured neutrino flux would be an indication for physics beyond the standard model | neutrino physics with darwin |
the electron-neutrino charged-current quasielastic (ccqe) cross section on nuclei is an important input parameter for electron neutrino appearance oscillation experiments. current experiments typically begin with the muon neutrino cross section and apply theoretical corrections to obtain a prediction for the electron neutrino cross section. however, at present no experimental verification of the estimates for this channel at an energy scale appropriate to such experiments exists. we present the cross sections for a ccqe-like process determined using the minerva detector, which are the first measurements of any exclusive reaction in few-gev electron neutrino interactions. the result is given as differential cross-sections vs the electron energy, electron angle, and square of the four-momentum transferred to the nucleus, q2. we also compute the ratio to a muon neutrino cross-section in q2 from minerva. we find satisfactory agreement between these measurements and the predictions of the genie generator. we furthermore report on a photon-like background unpredicted by the generator which we interpret as neutral-coherent diffractive scattering from hydrogen. | electron neutrino charged-current quasielastic scattering in the minerva experiment |
this paper reviews applications of two-phase emission detectors using xenon as working media. this kind of detectors invented at mephi is extremely sensitive to ionization (down to single electrons) and can be very massive (in ton scale) in order to provide high count rate for quite rare events and organize an active shielding from natural radioactivity in the wallles configuration of readout system. the emission detectors found their unique application in the most sensitive at the moment experiments searching for cold dark matter in the form of weakly interacting massive particles (wimps). the red-100 detector recently constructed at nrnu mephi can be used for the first observation of the elastic coherent neutrino scattering off xenon nuclei when the detector is installed practically on the earth’s surface. | two-phase emission detectors in search for rare events with low energy depositions |
the mössbauer spectroscopy is presented as an alternative experimental technique to be pursued in the detec-tion of coherent elastic{\nu}-nucleus scattering (cenns). the neutrino transferred energy in the neutrino-nucleusinteraction causes a perturbation at the nuclear levels which are responsible for gamma radiation in mössbauerresonance. the main characteristic of mössbauer spectroscopy is the recoil less condition imposed on the nucleiimposed by quantum restrictions of the crystalline array potential. coherent neutrino scattering is expected tooccurs low energy regime of the beam, typically below 30 mev, at higher neutrino energies small incoherencecomponent appears in the scattering[30] as disturbances within the internal nuclear degrees of freedom. inthis work we have shown that using anti neutrino reactor beam, with the accuracy of mössbauer technique itspossible to obtain a measurable signature of the coherent neutrino scattering. | searching signature of neutrino-nucleus coherent scattering with mössbauer spectroscopy |
sag4n is a code fully based on geant4 that we have developed to calculate neutron yields. the code is available in http://win.ciemat.es/sag4n and works for geant4.10.6 or superior. the improvements to the (α,n) yields introduced by the use of a single monte carlo code, fully developed in geant4, are presented. neutrons are a potential source of background for all rare-event searches, and is specially relevant for wimp searches with liquid argon, where they are the only source of irreducible background together with the yet-negligible coherent neutrino scattering. the precision of the neutron yield is critical to evaluate the discovery potential of coming experiments and to reduce systematic effects in current data. we present the result of evaluating the neutron yield for three different cases and show the sizable effect of interfaces between materials with high (α,n) cross section and materials with small mass which contribution to the neutron budget is often considered negligible. | sag4n: calculation of (α,n) yields for low background experiments using geant4 |
neutrino-induced coherent charged pion production is a unique neutrino-nucleus scattering process in which a muon and pion are produced while the nucleus is left in its ground state. the minerva experiment has made a model-independent differential cross section measurement of this process on carbon by selecting events with a muon and a pion, no evidence of nuclear break-up, and small momentum transfer to the nucleus | t | . a similar process which is a background to the measurement on carbon is diffractive pion production off the free protons in minerva's scintillator. this process is not modeled in the neutrino event generator genie. at low | t | these events have a similar final state to the aforementioned process. a study to quantify this diffractive event contribution to the background is done by emulating these diffractive events by reweighting all other genie-generated background events to the predicted | t | distribution of diffractive events, and then scaling to the diffractive cross section. | measurement of neutrino-induced coherent pion production and the diffractive background in minerva |
in light of independent verification of the muon (g-2) anomaly by fermilab and hints of a similar anomaly in the electron sector emerging from the improved measurement of fine-structure constant, it is important to ask if both these anomalies could have a common origin. i will talk about one such attempt involving contributions from a single z' of a u(1)' extension to the standard model (sm). i will first describe a model-independent analysis of various experimental constraints on the z' couplings to leptons and show that only a narrow region of parameter space with a mev-scale z' can account for both the anomalies. following this conclusion, i will show that any attempt to realize these couplings in a specific u(1)' extension of the sm fails as a result of an additional constraint from the gauge structure, and the stringency of neutrino scattering bounds. this leads us to conclude that no single u(1)' extension can resolve both the anomalies unless additional fields are introduced. a.b. and r.c. thank the organizers of the 2019 slac summer institute, 'menu of flavors', where this project was conceived and initiated. a.b. is supported by the nsf grant phy-1914731 and by the maryland center for fundamental physics (mcfp). r.c. is supported by the iisn convention 4.4503.15. r.c. thanks the unsw school of physics, where he is a visiting fellow, for their hospitality during part of this project. | solving leptonic (g-2) anomalies with a single z' |
the hera ep collider experiments have measured the proton structure functions over a wide kinematic range. new data from the h1 experiment now extend the range to higher 4-momentum transfer (√{q2 } ) over which a precision of ∼ 2% is achieved in the neutral current channel. a factor of two reduction in the systematic uncertainties over previous measurement is attained. the charged current structure function measurements are also significantly improved in precision. these data, when used in qcd analyses of the parton density functions (pdfs) reduce the pdf uncertainties particularly at high momentum fractions x which is relevant to low energy neutrino scattering cross sections. new data from the lhc pp collider experiments may also offer significant high x pdf improvements as the experimental uncertainties improve. | new dis and collider results on pdfs |
the coherent collaboration has been formed to make a first measurement of coherent neutral-current elastic neutrino-nucleus scattering (cenns). toward this, the spallation neutron source (sns) at oak ridge national laboratory has been identified as the premier facility for this measurement due to several factors, including: high neutrino flux, appropriate neutrino energies, sns beam time structure for significant background reduction, and the ability to suitably place detector systems sufficiently near the neutrino source. an ongoing background measurement campaign at the sns is identifying candidate locations and characterizing primary background signals for a cenns detector system. the result of current efforts and their implications for a cenns measurement at the sns will be discussed. | coherent first steps for an experimental neutrino program at the spallation neutron source |
neutrino-nucleon deep inelastic scattering (dis) events provide a probe into the structure of the nucleus that cannot be accessed via charged lepton-nucleon interactions. the minerva experiment is stationed in the neutrinos from the main injector (numi) beam line at fermi national accelerator laboratory. the projected sensitivity of nuclear structure function analyses using minerva's suite of nuclear targets (c, ch, fe and pb) in the upgraded 6 gev neutrino energy numi beam will be explored, and their impact discussed. | neutrino-nucleon deep inelastic scattering in minerva |
minerνa is a few-gev neutrino scattering experiment that has been taking data in the numi beam line at fermilab since november 2009. the experiment will provide important inputs, both in support of neutrino oscillation searches and as a pure weak probe of the nuclear medium. for this, minerva employs a fine-grained detector, with an eight ton active target region composed of plastic scintillator and a suite of nuclear targets composed of helium, carbon, iron, lead and water placed upstream of the active region. we will describe the current status of the charged current inclusive analysis in plastic scintillator. | minerνa charged current inclusive analysis |
a letter of intent has been submitted by a new international team to pursue an accelerator-based long-baseline neutrino experiment, as well as neutrino astrophysics and nucleon decay, with an approximately 40-kt (fiducial) modular liquid argon tpc (lar-tpc) detector located deep underground and a high-resolution near detector. several independent worldwide efforts, developed through years of detailed studies, are converging around the opportunity provided by the megawatt neutrino beam facility planned at fermilab and by the new significant expansion with improved access at the sanford underground research facility in south dakota, 1,300 km from fermilab. the principle goals of this experiment are: a comprehensive investigation of neutrino oscillations to test cp violation in the lepton sector, determine the ordering of the neutrino masses, and test the three-neutrino paradigm; to perform a broad set of neutrino scattering measurements with the near detector; and to exploit the large, high-resolution, underground far detector for non-accelerator physics topics including atmospheric neutrino measurements, searches for nucleon decay, and measurement of astrophysical neutrinos especially those from a core-collapse supernova. | an experimental program in neutrinos, nucleon decay and astroparticle physics enabled by the fermilab long-baseline neutrino facility |
recently, coupled-cluster computations were extended to electro-weak observables in light and medium-mass nuclei. in particular, we have reformulated the lorentz integral transform method within the coupled-cluster formalism to allow the investigation of break-up observables with the continuum properly taken into account. this new method, dubbed lit-cc, has permitted ab-initio studies of photodisintegration cross sections in stable nuclei (16o, 40ca) and coulomb break-up cross sections in unstable nuclei (22o). next, we aim at studying gamow-teller strengths distribution using this method. i will report on a recent calculation of the total gamow-teller strength in the beta decay of 14c, 22o and 24o. we found that two-body currents lead to a quenching of the ikeda sum rule and it is interesting to see how the strength is distributed. this will be studied using the lit-cc method. finally, our long term goal is to tackle neutrino-nucleus interactions using this coupled-cluster theory. neutrino cross sections and nuclear effects lead to systematic uncertainty in the extraction of oscillation parameters in neutrino experiments. because detectors include complex nuclei, knowledge of their interactions with neutrinos is required with quantified uncertainties to be used in simulations. the lit-cc method is well suited to investigate the charge-changing quasi elastic peak in neutrino scattering. while our goal is to tackle the weak response in 16o, i will show some preliminary results on 4he, in particular regarding the coulomb sum rule. support from nserc and nrc is acknowledged. | coupled-cluster computation of electroweak observables |
we report on an accurate variational many-body technique (cluster variational monte carlo) suitable for the study of medium-mass nuclei. the employed many-body nuclear hamiltonian contains realistic two- and three-nucleon interactions and the trial wave function is constructed from pair- and triplet-correlation operators acting on a product of single-particle determinants. as opposed to traditional variational monte carlo calculations, that are limited to a = 12 nuclei, expectation values are evaluated with a cluster expansion for the non-central correlations. the cluster expansion drastically reduces the computational effort necessary for the study of an a-body system, allowing us to extend the calculations in the medium-mass region, currently up to 40 nucleons. we present results for the closed-shell nuclei 16o and 40ca and prospects for open-shell nuclei like 40ar. of particular interest is the derivation of the momentum distributions that can be used to constrain the spectral functions of these nuclei. this has a crucial interplay with electron-nucleon and neutrino-nucleon scattering experiments, where argon is among the typical targets and the scattering data at high momentum transfer can be analyzed by means of the spectral function formalism. this work is supported by the u.s. department of energy, office of science, office of nuclear physics, under the nuclei scidac grant and contract no. de-ac02-06ch11357. | a variational monte carlo approach for the study of medium-mass nuclei |
we present a derivation of the total cross section for inelastic scattering of low-energy solar neutrinos and reactor antineutrinos on bound electrons, resulting in a transition of the electron to an excited state. the atomic-shell structure of various chemical elements is treated in terms of a nonrelativistic approximation. we estimate the interaction rates for modern neutrino detectors, in particular the borexino and gemma experiments. we establish that in these experiments the effect can be safely neglected, but it could be accessible to future large-volume neutrino detectors with low energy threshold. | scattering of low-energy neutrinos on atomic shells |
results from recent experiments show that short-range interactions between the fermions form correlated, high-momentum, neutron-proton pairs. these pairs dominate the momentum distribution of nucleons above the fermi momentum of the nucleus. the observed dominance of these short-range correlated (src) pairs by neutron-proton pairs shows the dominance of the tensor part of the nucleon-nucleon interaction at short distances. recent works have shown that the existence and nature of src pairs has wide ranging implications for atomic, nuclear and astro physics, including neutrino-nucleus scattering, the emc effect, the nutev anomaly, the nuclear symmetry energy. in this talk i will present the possibility of studying src pairs and their partonic structure at an eic, using the method of spectator tagging in quasi-elastic and deep-inelastic kinematics. we can identify qe or dis scattering from nucleons in correlated pairs by tagging a spectator nucleon with higher momentum than its initial momentum in the beam. | tagging correlations at an eic |
unanswered and interesting questions arise in the leptonic sector of the standard model of particle physics: are there new sources of cp violation? are the neutrinos dirac or majorana particles? are there more than one higgs doublet that modify the leptonic or semileptonic decays of mesons? all these questions may be answered by a detailed study of low energy experiments. in this talk we present a short review of some examples where using present or future data on d meson decays, neutrino scattering on electron or coherent scattering on nucleus and neutrinos produced in accelerators may help us to answer those questions. | towards the low energy frontier |
with their complex low-spin structure, the germanium isotopes have accrued a large number of experimental data which challenge nuclear models. the structure of the 74ge isotope is investigated here with nuclear resonance fluorescence as part of an extensive campaign of experimental tests of the shell model in the germanium isotopic chain using a number of complementary techniques. levels were excited with 3.10 -5.44 mev photon beams provided by the high intensity gamma-ray source at tunl. many new levels were identified and their spins, parities, branching ratios, and associated scattering cross section values were determined. large-scale shell-model calculations, which include jj44b and jun45 effective interactions developed to describe nuclei in this mass region, predict the new data satisfactorily. this study extends the validation of these two interactions, which are candidates for computation of matrix elements to be used in the interpretation of neutrinoless double-β decay experiments in 76ge, into the low-spin, high excitation energy domain. | testing shell-model interactions at high excitation energy and low spin: nuclear resonance fluorescence in 74ge |
nuclei that are unstable with respect to double beta decay are investigated in this work for a novel dark matter (dm) direct detection approach. in particular, the diagram responsible for the neutrinoless double beta decay can be considered for the possible detection technique of a majorana dm fermion inelastically scattering on a double beta unstable nucleus, stimulating its decay. the exothermic nature of the stimulated double beta decay would allow the direct detection also of a light dm fermion, a class of dm candidates that are difficult or impossible to investigate with the traditional elastic scattering techniques. the expected signal distribution for different dm masses and the upper limits on the nucleus scattering cross sections, are shown and compared with the existing data for the case of 136xe nucleus. | investigation of light dark matter with 2β decay experiments |
the first observation of the coherent elastic neutrino-nucleus scattering (ce νns) by the cohernet experiment using accelerator neutrinos rendered opportunities for abundant scientific and technological applications. to study the ce νns process precisely, a project using cryogenic bolometer technology with lead tungstate (pbwo4) as a detector candidate and a nuclear reactor as a neutrino source is proposed. by taking a typical reactor, the china taishan nuclear power plant, as a reference, a flux of 6 . 7 × 1016 m-2 s-1 with energy below 10 mev can be realized at an experimental site located approximately ∼30 meters away from one of the 4.6 gwth thermal power taishan reactor cores. the specific heat of pbwo4, which is an important detector research and design parameter, was measured for the first time at o(500) mk, and the results were found to be consistent with the prediction of debye model. the phonon-only response of a pbwo4 crystal to the energy deposits at very low temperatures may offer high sensitivity to the small nucleus recoil ce νns signal. a configuration using a one-gram pbwo4 cube as a detector unit working at a temperature of o(10) mk, together with novel phonon sensor technology sensitive to nucleus recoil energy as low as o(10) ev, is hypothesized as the ideal experiment benchmark. consequently, a signal rate of around 200 reactor neutrino coherent scattering events can be expected per day with a one-kilogram pbwo4 detector volume, against ∼20 background counts in the optimized signal region. | study of a coherent elastic neutrino-nucleus scattering experiment at a reactor with a pbwo4-based bolometer |
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