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interpreting and modelling astronomical catalogues requires an understanding of the catalogues' completeness or selection function: what properties determine an object's probability of being including in the catalogue? here we set out to empirically quantify the completeness of the overall catalogue of gaia's third dat... | an empirical model of the gaia dr3 selection function |
we present the distance priors from the finally released planck tt, te, ee+lowe data in 2018. the uncertainties are around 40% smaller than those from planck 2015 tt+lowp. in order to check the validity of these new distance priors, we adopt the distance priors to constrain the cosmological parameters in different dark... | distance priors from planck final release |
we derive limits on millicharged dark states, as well as particles with electric or magnetic dipole moments, from the number of observed forward electron scattering events at the big european bubble chamber in the 1982 cern-wa-066 beam dump experiment. the dark states are produced by the 400 gev proton beam primarily t... | blast from the past: constraints on the dark sector from the bebc wa66 beam dump experiment |
in this work, a spherically symmetric and static relativistic anisotropic fluid sphere solution of the einstein field equations is provided. to build this particular model, we have imposed metric potential e2 λ (r ) and an equation of state. specifically, the so-called modified generalized chaplygin equation of state w... | relativistic anisotropic fluid spheres satisfying a non-linear equation of state |
the extreme ultraviolet (euv) monitor is an instrument on the nasa mars atmosphere and volatile evolution (maven) mission, designed to measure the variability of the solar soft x-rays and euv irradiance at mars. the solar output in this wavelength range is a primary energy input to the mars atmosphere and a driver for ... | the solar extreme ultraviolet monitor for maven |
in this paper, our main concern is to obtain the geometrical structure of a thin-shell through the match of inner flat and outer the renormalization group improved schwarzschild black hole through a well-known cut and paste approach. then, we are interested to discuss the dynamical configuration of thin-shell composed ... | stability and dynamics of scalar field thin-shell for renormalization group improved schwarzschild black holes |
a rapid phantom transition of the dark energy equation of state parameter w at a transition redshift zt<0.1 of the form w (z )=-1 +δ w θ (zt-z ) with δ w <0 can lead to a higher value of the hubble constant while closely mimicking a planck 18 /λ cdm form of the comoving distance r (z )=∫0zd/z' h (z') for z >zt... | w -m phantom transition at zt<0.1 as a resolution of the hubble tension |
we describe the simulated data sample for the photometric large synoptic survey telescope (lsst) astronomical time series classification challenge (plasticc), a publicly available challenge to classify transient and variable events that will be observed by the lsst, a new facility expected to start in the early 2020s. ... | models and simulations for the photometric lsst astronomical time series classification challenge (plasticc) |
early dark energy (ede) offers a solution to the so-called hubble tension. recently, it was shown that the constraints on ede using markov chain monte carlo are affected by prior volume effects. the goal of this paper is to present constraints on the fraction of ede, fede, and the hubble parameter, h0, which are not su... | resolving the hubble tension with early dark energy |
in this letter, we consider the possibility of reconciling metric theories of gravitation with a violation of the conservation of energy-momentum. under some circumstances, this can be achieved in the context of unimodular gravity, and it leads to the emergence of an effective cosmological constant in einstein's equati... | dark energy from violation of energy conservation |
we investigate the landscape of constraints on mev-gev scale, hidden u(1) forces with nonzero axial-vector couplings to standard model fermions. while the purely vector-coupled dark photon, which may arise from kinetic mixing, is a well-motivated scenario, several mev-scale anomalies motivate a theory with axial coupli... | light weakly coupled axial forces: models, constraints, and projections |
in a model independent approach, we derive generic conditions that any late time modification of the λcdm expansion history must satisfy in order to consistently solve both the h0 and the σ8 tensions. our results are fully analytical and the method is merely based on the assumption that the late-time deviations from λc... | simultaneously solving the h0 and σ8 tensions with late dark energy |
image reconstruction is essential for imaging applications across the physical and life sciences, including optical and radar systems, magnetic resonance imaging, x-ray computed tomography, positron emission tomography, ultrasound imaging and radio astronomy. during image acquisition, the sensor encodes an intermediate... | image reconstruction by domain-transform manifold learning |
terahertz (thz) radiation encompasses a wide spectral range within the electromagnetic spectrum that extends from microwaves to the far infrared (100 ghz-~30 thz). within its frequency boundaries exist a broad variety of scientific disciplines that have presented, and continue to present, technical challenges to resear... | the 2023 terahertz science and technology roadmap |
explores all aspects of radio interferometry in depth with full, relevant mathematical derivations. provides extensive updates to the second edition, including results and technical advances from the past decade; discussion of arrays that now span the full range of the radio part of the electromagnetic spectrum observa... | interferometry and synthesis in radio astronomy, 3rd edition |
highly sensitive phase- and frequency-resolved detection of microwave electric fields is of central importance in a wide range of fields, including cosmology1,2, meteorology3, communication4 and microwave quantum technology5. atom-based electrometers6,7 promise traceable standards for microwave electrometry, but their ... | atomic superheterodyne receiver based on microwave-dressed rydberg spectroscopy |
more than a decade after their discovery, astronomical fast radio bursts remain enigmatic. they are known to occur at "cosmological" distances, implying large energy and radiated power, extraordinarily high brightness temperature and coherent emission. yet their source objects, the means by which energy is released and... | fast radio bursts |
we describe an ultra-wide-bandwidth, low-frequency receiver recently installed on the parkes radio telescope. the receiver system provides continuous frequency coverage from 704 to 4032 mhz. for much of the band ( ${∼}60%$ ), the system temperature is approximately 22 k and the receiver system remains in a linear regim... | an ultra-wide bandwidth (704 to 4 032 mhz) receiver for the parkes radio telescope |
the very large array sky survey (vlass) is observing the entire sky north of -40° in the s band (2 ghz < ν < 4 ghz), with the highest angular resolution (2"5) of any all-sky radio continuum survey to date. vlass will cover its entire footprint over three distinct epochs, the first of which has now been observed i... | a quick look at the 3 ghz radio sky. i. source statistics from the very large array sky survey |
we propose a method for optical interferometry in telescope arrays assisted by quantum networks. in our approach, the quantum state of incoming photons along with an arrival time index are stored in a binary qubit code at each receiver. nonlocal retrieval of the quantum state via entanglement-assisted parity checks at ... | optical interferometry with quantum networks |
much like six-membered rings, five-membered rings are ubiquitous in organic chemistry, frequently serving as the building blocks for larger molecules, including many of biochemical importance. from a combination of laboratory rotational spectroscopy and a sensitive spectral line survey in the radio band toward the star... | interstellar detection of the highly polar five-membered ring cyanocyclopentadiene |
we describe a new multiscale deconvolution algorithm that can also be used in a multifrequency mode. the algorithm only affects the minor clean loop. in single-frequency mode, the minor loop of our improved multiscale algorithm is over an order of magnitude faster than the casa multiscale algorithm, and produces result... | an optimized algorithm for multiscale wideband deconvolution of radio astronomical images |
the maser—the microwave progenitor of the optical laser—has been confined to relative obscurity owing to its reliance on cryogenic refrigeration and high-vacuum systems. despite this, it has found application in deep-space communications and radio astronomy owing to its unparalleled performance as a low-noise amplifier... | continuous-wave room-temperature diamond maser |
new iram kid array 2 (nika2) is a camera dedicated to millimeter-wave astronomy based upon kilopixel arrays of kinetic inductance detectors [1] (kid). the pathfinder instrument, nika [2], has already shown state-of-the-art detector performance. nika2 builds upon this experience but goes one step further, increasing the... | the nika2 instrument, a dual-band kilopixel kid array for millimetric astronomy |
fast radio bursts (frbs) are millisecond-duration events thought to originate beyond the milky way galaxy. uncertainty surrounding the burst sources, and their propagation through intervening plasma, has limited their use as cosmological probes. we report on a mildly dispersed (dispersion measure 266.5 ± 0.1 parsecs pe... | the magnetic field and turbulence of the cosmic web measured using a brilliant fast radio burst |
thunderstorms are natural laboratories for studying electrical discharges in air, where the vast temporal, spatial, and energy scales available can spawn surprising phenomena that reveal deficiencies in our understanding of dielectric breakdown. recent discoveries, such as sprites, jets, terrestrial gamma ray flashes, ... | fast negative breakdown in thunderstorms |
we have developed a new coherent dedispersion mode to study the emission of fast radio bursts (frbs) that trigger the voltage capture capability of the australian ska pathfinder (askap) interferometer. in principle the mode can probe emission timescales down to 3 ns with full polarimetric information preserved. enabled... | spectropolarimetric analysis of frb 181112 at microsecond resolution: implications for fast radio burst emission mechanism |
the event horizon telescope (eht) is a very long-baseline interferometer built to image supermassive black holes on event-horizon scales. in this paper, we investigate candidate sites for an expanded eht array with improved imaging capabilities. we use historical meteorology and radiative transfer analysis to evaluate ... | evaluation of new submillimeter vlbi sites for the event horizon telescope |
galaxy clusters are the most massive gravitationally bound structures in the universe. they grow by accreting smaller structures in a merging process that produces shocks and turbulence in the intracluster gas. we observed a ridge of radio emission connecting the merging galaxy clusters abell 0399 and abell 0401 with t... | a radio ridge connecting two galaxy clusters in a filament of the cosmic web |
the ideal text for a one-semester course in radio astronomyessential radio astronomy is the only textbook on the subject specifically designed for a one-semester introductory course for advanced undergraduates or graduate students in astronomy and astrophysics. it starts from first principles in order to fill gaps in s... | essential radio astronomy |
we use deep panchromatic data sets in the goods-n field, from galex to the deepest herschel far-infrared (fir) and vla radio continuum imaging, to explore the evolution of star-formation activity and dust attenuation properties of star-forming galaxies to z ≃ 4, using mass-complete samples. our main results can be summ... | goods-herschel: star formation, dust attenuation, and the fir-radio correlation on the main sequence of star-forming galaxies up to z ≃4 |
context. urea, nh2c(o)nh2, is a molecule of great importance in organic chemistry and biology. two searches for urea in the interstellar medium have been reported in the past, but neither were conclusive.aims: we want to take advantage of the increased sensitivity and angular resolution provided by the atacama large mi... | re-exploring molecular complexity with alma (remoca): interstellar detection of urea |
tidal disruption events (tdes) are transient flares produced when a star is ripped apart by the gravitational field of a supermassive black hole (smbh). we have observed a transient source in the western nucleus of the merging galaxy pair arp 299 that radiated >1.5 × 1052 erg at infrared and radio wavelengths but wa... | a dust-enshrouded tidal disruption event with a resolved radio jet in a galaxy merger |
conventional mirrors obey the simple reflection law that a plane wave is reflected as a plane wave, at the same angle. to engineer spatial distributions of fields reflected from a mirror, one can either shape the reflector or position some phase-correcting elements on top of a mirror surface. here we show, both theoret... | functional metamirrors using bianisotropic elements |
the co mapping array project (comap) aims to use line-intensity mapping of carbon monoxide (co) to trace the distribution and global properties of galaxies over cosmic time, back to the epoch of reionization (eor). to validate the technologies and techniques needed for this goal, a pathfinder instrument has been constr... | comap early science. i. overview |
the compact configuration of phase ii of the murchison widefield array (mwa) consists of both a redundant subarray and pseudo-random baselines, offering unique opportunities to perform sky-model and redundant interferometric calibration. the highly redundant hexagonal cores give improved power spectrum sensitivity. in ... | first season mwa phase ii epoch of reionization power spectrum results at redshift 7 |
the upper mid-band - roughly from 7 to 24 ghz - has attracted considerable recent interest for new cellular services. this frequency range has vastly more spectrum than the highly congested bands below 7 ghz while offering more favorable propagation and coverage than the millimeter wave (mmwave) frequencies. the upper ... | cellular wireless networks in the upper mid-band |
this paper offers an electromagnetic, more specifically array theory, perspective on understanding strong instrumental polarization effects for planar low-frequency "aperture arrays" with the murchison widefield array (mwa) as an example. a long-standing issue that has been seen here is significant instrumental stokes ... | understanding instrumental stokes leakage in murchison widefield array polarimetry |
fast radio bursts (frbs) are millisecond-duration pulses of radio emission originating from extragalactic distances. radio dispersion is imparted on each burst by intervening plasma, mostly located in the intergalactic medium. in this work, we observe the burst frb 20220610a and localize it to a morphologically complex... | a luminous fast radio burst that probes the universe at redshift 1 |
the icecube neutrino observatory sends realtime neutrino alerts with a high probability of being astrophysical in origin. we present a new method to correlate these events and possible candidate sources using 2089 blazars from the fermi-lat 4lac-dr2 catalog and with 3413 active galactic nuclei (agns) from the radio fun... | search for correlations of high-energy neutrinos detected in icecube with radio-bright agn and gamma-ray emission from blazars |
we present the discovery and subarcsecond localization of a new fast radio burst (frb) by the karl g. jansky very large array (vla) and realfast search system. the frb was discovered on 2019 june 14 with a dispersion measure of 959 $\mathrm{pc}\,{\mathrm{cm}}^{-3}$. this is the highest dm of any localized frb and its m... | a distant fast radio burst associated with its host galaxy by the very large array |
astrochemistry lies at the nexus of astronomy, chemistry, and molecular physics. on the basis of precise laboratory data, a rich collection of more than 200 familiar and exotic molecules have been identified in the interstellar medium, the vast majority by their unique rotational fingerprint. despite this large body of... | aromatics and cyclic molecules in molecular clouds: a new dimension of interstellar organic chemistry |
the synthesis of ultralow-noise microwaves is of both scientific and technological relevance for timing, metrology, communications and radio-astronomy. today, the lowest reported phase noise signals are obtained via optical frequency-division using mode-locked laser frequency combs. nonetheless, this technique ideally ... | ultralow-noise photonic microwave synthesis using a soliton microcomb-based transfer oscillator |
m87 has been the target of numerous astronomical observations across the electromagnetic spectrum, and very long baseline interferometry has resolved an edge-brightened jet1-4. however, the origin and formation of its jets remain unclear. in our current understanding, black holes (bh) are the driving engine of jet form... | state-of-the-art energetic and morphological modelling of the launching site of the m87 jet |
ultra-high angular resolution in astronomy has always been an important vehicle for making fundamental discoveries. recent results in direct imaging of the vicinity of the supermassive black hole in the nucleus of the radio galaxy m87 by the millimeter vlbi system event horizon telescope and various pioneering results ... | the science case and challenges of space-borne sub-millimeter interferometry |
the tidal disruption of a star by a supermassive black hole leads to a short-lived thermal flare. despite extensive searches, radio follow-up observations of known thermal stellar tidal disruption flares (tdfs) have not yet produced a conclusive detection. we present a detection of variable radio emission from a therma... | a radio jet from the optical and x-ray bright stellar tidal disruption flare asassn-14li |
the australian ska pathfinder (askap) is being used to undertake a campaign to rapidly survey the sky in three frequency bands across its operational spectral range. the first pass of the rapid askap continuum survey (racs) at 887.5 mhz in the low band has already been completed, with images, visibility datasets, and c... | the rapid askap continuum survey iv: continuum imaging at 1367.5 mhz and the first data release of racs-mid |
among the prominent candidates for dark matter are bosonic fields with small scalar couplings to the standard-model particles. several techniques are employed to search for such couplings, and the current best constraints are derived from tests of gravity or atomic probes. in experiments employing atoms, observables wo... | scalar dark matter in the radio-frequency band: atomic-spectroscopy search results |
we present the first interferometric detections of fast radio bursts (frbs), an enigmatic new class of astrophysical transient. in a 180-d survey of the southern sky, we discovered three frbs at 843 mhz with the utmost array, as a part of commissioning science during a major ongoing upgrade. the wide field of view of u... | the first interferometric detections of fast radio bursts |
we present the muse-wide survey, a blind, 3d spectroscopic survey in the candels/goods-s and candels/cosmos regions. the final survey will cover 100 × 1 arcmin2 muse fields. each muse-wide pointing has a depth of one hour and hence targets more extreme and more luminous objects over ten times the area of the muse-deep ... | the muse-wide survey: survey description and first data release |
33 fast radio bursts (frbs) had been detected by 2018 march. although the sample size is still limited, meaningful statistical studies can already be carried out. the normalized luminosity function places important constraints on the intrinsic power output, sheds light on the origin(s) of frbs, and can guide future obs... | on the normalized frb luminosity function |
in the presence of magnetic fields, gravitational waves are converted into photons and vice versa. we demonstrate that this conversion leads to a distortion of the cosmic microwave background (cmb), which can serve as a detector for mhz to ghz gravitational wave sources active before reionization. the measurements of t... | potential of radio telescopes as high-frequency gravitational wave detectors |
benzonitrile (c-c6h5cn, where `c' indicates a cyclic structure), a polar proxy for benzene (c-c6h6), has the potential to serve as a highly convenient radio probe for aromatic chemistry, provided that this ring can be found in other astronomical sources beyond the molecule-rich prestellar cloud tmc-1. here we present r... | ubiquitous aromatic carbon chemistry at the earliest stages of star formation |
advanced ligo’s second observing run (o2), conducted from 2016 november 30 to 2017 august 25, combined with advanced virgo’s first observations in 2017 august, witnessed the birth of gravitational-wave multimessenger astronomy. the first ever gravitational-wave detection from the coalescence of two neutron stars, gw170... | low-latency gravitational-wave alerts for multimessenger astronomy during the second advanced ligo and virgo observing run |
one of the last unexplored windows to the cosmos, the dark ages and cosmic dawn, can be opened using a simple low frequency radio telescope from the stable, quiet lunar farside to measure the global 21-cm spectrum. this frontier remains an enormous gap in our knowledge of the universe. standard models of physics and co... | global 21-cm cosmology from the farside of the moon |
the first rovibrational (ir) and rotational (mm-wave) spectra are measured for c-c3h2d+, a potential detection target in interstellar space. applying a novel action spectroscopic technique in a 4 k cryogenic ion-trap instrument, the molecule c-c3h2d+ has been investigated by high-resolution rovibrational and pure rotat... | high-resolution rovibrational and rotational spectroscopy of the singly deuterated cyclopropenyl cation, c-c3h2d+ |
aims: high-synchrotron peaked blazars (hsps or hbls) play a central role in very high-energy (vhe) γ-ray astronomy, and likely in neutrino astronomy. currently, the largest compilation of hsp blazars, the 2whsp sample, includes 1691 sources, but it is not complete in the radio or in the x-ray band. in order to provide ... | the 3hsp catalogue of extreme and high-synchrotron peaked blazars |
context. n-methylformamide, ch3nhcho, may be an important molecule for interstellar pre-biotic chemistry because it contains a peptide bond, which in terrestrial chemistry is responsible for linking amino acids in proteins. the rotational spectrum of the most stable trans conformer of n-methylformamide is complicated b... | rotational spectroscopy, tentative interstellar detection, and chemical modeling of n-methylformamide |
the effect of satellite mega-constellations on astronomical observations in the visible, near-infrared, and thermal infrared domains is estimated using a simple methodology, which is applied to eso telescopes and instruments as examples (radio and (sub-)millimetre domains are not considered here). the study considers a... | impact of satellite constellations on astronomical observations with eso telescopes in the visible and infrared domains |
following a tidal disruption event (tde), the accretion rate can evolve from quiescent to near-eddington levels and back over timescales of months to years. this provides a unique opportunity to study the formation and evolution of the accretion flow around supermassive black holes (smbhs). we present 2 yr of multiwave... | rapid accretion state transitions following the tidal disruption event at2018fyk |
we present lofar observations of one of the most spectacular objects in the radio sky: abell 2255. this is a nearby (z = 0.0806) merging galaxy cluster hosting one of the first radio halos ever detected in the intracluster medium (icm). the deep lofar images at 144 mhz of the central ∼10 mpc2 region show a plethora of ... | the beautiful mess in abell 2255 |
we present our observations of electromagnetic transients associated with gw170817/grb 170817a using optical telescopes of chilescope observatory and big scanning antenna (bsa) of pushchino radio astronomy observatory at 110 mhz. the chilescope observatory detected an optical transient of ∼19m on the third day in the o... | grb 170817a associated with gw170817: multi-frequency observations and modeling of prompt gamma-ray emission |
solar flares—the most powerful explosions in the solar system—are also efficient particle accelerators, capable of energizing a large number of charged particles to relativistic speeds. a termination shock is often invoked in the standard model of solar flares as a possible driver for particle acceleration, yet its exi... | particle acceleration by a solar flare termination shock |
the event horizon telescope (eht) has recently delivered the first resolved images of m87*, the supermassive black hole in the center of the m87 galaxy. these images were produced using 230 ghz observations performed in 2017 april. additional observations are required to investigate the persistence of the primary image... | monitoring the morphology of m87* in 2009-2017 with the event horizon telescope |
detection of the cosmological neutral hydrogen signal from the epoch of reionization (eor) and estimation of its basic physical parameters are principal scientific aims of many current low-frequency radio telescopes. here we describe the cosmological h i power spectrum estimator (chips), an algorithm developed and impl... | chips: the cosmological h i power spectrum estimator |
we announce here the public availability of a catalog of ν ∼ 3 ghz quick look observations from the first epoch of the very large array sky survey. the catalog consists of three distinct and linkable tables, namely (a) the detected radio components, (b) the host identifications with total source properties for single-c... | a catalog of very large array sky survey epoch 1 quick look components, sources, and host identifications |
after a decade of design and construction, south africa's ska-mid precursor meerkat has begun its science operations. to make full use of the widefield capability of the array, it is imperative that we have an accurate model of the primary beam of its antennas. we have taken available l-band full-polarization 'astro-ho... | primary beam effects of radio astronomy antennas - ii. modelling meerkat l-band beams |
the energy released by active galactic nuclei (agn) in the form of radiation, winds or radio plasma jets, is known to impact on the surrounding interstellar medium. the result of these processes, known as agn (negative) feedback, is suggested to prevent gas, in and around galaxies, from cooling, and to remove, or at le... | the many routes to agn feedback |
the rapid development of superconducting quantum hardware is expected to run into significant i/o restrictions due to the need for large-scale error correction in a cryogenic environment. classical data centers rely on fiber-optic interconnects to remove similar networking bottlenecks and to allow for reconfigurable, s... | all-optical single-shot readout of a superconducting qubit |
radial velocity (rv) is among the most fundamental physical quantities obtainable from stellar spectra and is rather important in the analysis of time-domain phenomena. lamost medium-resolution survey (mrs) dr7 contains five million single-exposure stellar spectra with spectral resolution r ~ 7500. however, the tempora... | self-consistent stellar radial velocities from lamost medium-resolution survey dr7 |
we present a catalog of emissive point sources detected in the spt-sz survey, a contiguous 2530 square degree area surveyed with the south pole telescope (spt) from 2008-2011 in three bands centered at 95, 150, and 220 ghz. the catalog contains 4845 sources measured at a significance of 4.5σ or greater in at least one ... | millimeter-wave point sources from the 2500 square degree spt-sz survey: catalog and population statistics |
oxkat semi-automatically performs calibration and imaging of data from the meerkat radio telescope. taking as input raw visibilities in measurement set format, the entire processing workflow is covered, from flagging and reference calibration, to imaging and self-calibration, and (optionally) direction-dependent calibr... | oxkat: semi-automated imaging of meerkat observations |
the galaxy and mass assembly survey (gama) covers five fields with highly complete spectroscopic coverage (>95 per cent) to intermediate depths (r < 19.8 or i < 19.0 mag), and collectively spans 250 deg2 of equatorial or southern sky. four of the gama fields (g09, g12, g15, and g23) reside in the european sout... | galaxy and mass assembly (gama): assimilation of kids into the gama database |
using the nsf's karl g. jansky very large array (vla), we report six detections of co(j = 1 → 0) emission and one upper limit in z = 2-3 galaxies originally detected in higher-j co emission in the atacama large millimeter/submillimeter array spectroscopic survey in the hubble ultra deep field (aspecs). from the co(j = ... | vla-alma spectroscopic survey in the hubble ultra deep field (vlaspecs): total cold gas masses and co line ratios for z = 2-3 main-sequence galaxies |
sulfur-bearing molecules play an important role in prebiotic chemistry and planet habitability. they are also proposed probes of chemical ages, elemental c/o ratio, and grain chemistry processing. commonly detected in diverse astrophysical objects, including the solar system, their distribution and chemistry remain, ho... | molecules with alma at planet-forming scales (maps). xii. inferring the c/o and s/h ratios in protoplanetary disks with sulfur molecules |
general relativity predicts that images of optically thin accretion flows around black holes should generically have a "photon ring", composed of a series of increasingly sharp subrings that correspond to increasingly strongly lensed emission near the black hole. because the effects of lensing are determined by the spa... | measuring photon rings with the ngeht |
the majority of stars are part of gravitationally bound stellar systems, such as binaries. observations of protobinary systems constrain the conditions that lead to stellar multiplicity and subsequent orbital evolution. we report high-angular resolution observations of the circumbinary disk around [bhb2007] 11, a young... | gas flow and accretion via spiral streamers and circumstellar disks in a young binary protostar |
we present a technique-led review of the progression of precise radio astrometry, from the first demonstrations, half a century ago, until to date and into the future. we cover the developments that have been fundamental to allow high accuracy and precision astrometry to be regularly achieved. we review the opportuniti... | precise radio astrometry and new developments for the next-generation of instruments |
the hydrogen intensity and real-time analysis experiment (hirax) is a radio interferometer array currently in development, with an initial 256-element array to be deployed at the south african radio astronomy observatory square kilometer array site in south africa. each of the 6 m, f / 0.23 dishes will be instrumented ... | hydrogen intensity and real-time analysis experiment: 256-element array status and overview |
we present the discovery of an extreme flaring event from proxima cen by the australian square kilometre array pathfinder (askap), atacama large millimeter/submillimeter array (alma), hubble space telescope (hst), transiting exoplanet survey satellite (tess), and the du pont telescope that occurred on 2019 may 1. in th... | discovery of an extremely short duration flare from proxima centauri using millimeter through far-ultraviolet observations |
we present high-resolution observations of the 880 μm (rest-frame fir) continuum emission in the z = 4.05 submillimeter galaxy gn20 from the iram plateau de bure interferometer (pdbi). these data resolve the obscured star formation (sf) in this unlensed galaxy on scales of 0.''3 × 0.''2 (~2.1 × 1.3 kpc). the observatio... | the kiloparsec-scale star formation law at redshift 4: widespread, highly efficient star formation in the dust-obscured starburst galaxy gn20 |
context. over the past five decades, radio astronomy has shown that molecular complexity is a natural outcome of interstellar chemistry, in particular in star forming regions. however, the pathways that lead to the formation of complex molecules are not completely understood and the depth of chemical complexity has not... | exploring molecular complexity with alma (emoca): alkanethiols and alkanols in sagittarius b2(n2) |
we present the current state of models for the z ~ 3 carbon monoxide (co) line intensity signal targeted by the co mapping array project (comap) pathfinder in the context of its early science results. our fiducial model, relating dark matter halo properties to co luminosities, informs parameter priors with empirical mo... | comap early science. v. constraints and forecasts at z 3 |
we present neutron star interior composition explorer x-ray and arcminute microkelvin imager large array radio observations of a rapid hard-to-soft state transition in the black hole x-ray transient maxi j1820+070. during the transition from the hard state to the soft state a switch between two particular types of quas... | a rapid change in x-ray variability and a jet ejection in the black hole transient maxi j1820+070 |
the goal of the search for extraterrestrial intelligence (seti) is to quantify the prevalence of technological life beyond earth via their `technosignatures'. one theorized technosignature is narrowband doppler drifting radio signals. the principal challenge in conducting seti in the radio domain is developing a genera... | a deep-learning search for technosignatures from 820 nearby stars |
as a product of the maser monitoring program with the 26 m telescope of the hartebeesthoek radio astronomy observatory (hartrao), we present an unprecedented, contemporaneous flaring event of 10 maser transitions in hydroxyl, methanol, and water that began in 2015 january in the massive star-forming region ngc 6334i in... | a masing event in ngc 6334i: contemporaneous flaring of hydroxyl, methanol, and water masers |
detecting weak radio-frequency electromagnetic fields plays a crucial role in a wide range of fields, from radio astronomy to nuclear magnetic resonance imaging. in quantum optics, the ultimate limit of a weak field is a single photon. detecting and manipulating single photons at megahertz frequencies presents a challe... | observation and stabilization of photonic fock states in a hot radio-frequency resonator |
the event horizon telescope (eht) collaboration has recently produced the first resolved images of the central supermassive black hole in the giant elliptical galaxy m87. here we report on tests of the consistency and accuracy of the general relativistic radiative transfer codes used within the collaboration to model m... | verification of radiative transfer schemes for the eht |
an array of low-frequency dipole antennas on the lunar farside surface will probe a unique, unexplored epoch in the early universe called the dark ages. it begins at recombination when neutral hydrogen atoms formed, first revealed by the cosmic microwave background. this epoch is free of stars and astrophysics, so it i... | a lunar farside low radio frequency array for dark ages 21-cm cosmology |
we present x-ray, uv, optical, and radio observations of the nearby (≈78 mpc) tidal disruption event at2021ehb/ztf21aanxhjv during its first 430 days of evolution. at2021ehb occurs in the nucleus of a galaxy hosting a≈107 m ⊙ black hole (m bh inferred from host galaxy scaling relations). high-cadence swift and neutron ... | the tidal disruption event at2021ehb: evidence of relativistic disk reflection, and rapid evolution of the disk-corona system |
an optoelectronic oscillator (oeo) is a microwave photonic system that produces microwave signals with ultralow phase noise using a high-quality-factor optical energy storage element. this type of oscillator is desired in various practical applications, such as communication links, signal processing, radar, metrology, ... | recent advances in optoelectronic oscillators |
we describe the performance of the boolardy engineering test array, the prototype for the australian square kilometre array pathfinder telescope. boolardy engineering test array is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine d... | the australian square kilometre array pathfinder: performance of the boolardy engineering test array |
fast radio bursts (frbs) are mysterious millisecond pulses in radio, most of which originate from distant galaxies. revealing the origin of frbs is becoming central in astronomy. the redshift evolution of the frb energy function, i.e. the number density of frb sources as a function of energy, provides important implica... | energy functions of fast radio bursts derived from the first chime/frb catalogue |
rapid rotation is a fundamental characteristic of classical be stars and a crucial property allowing for the formation of their circumstellar disks. past evolution in a mass and angular momentum transferring binary system offers a plausible solution to how be stars attained their fast rotation. although the subdwarf re... | prevalence of sed turndown among classical be stars: are all be stars close binaries? |
motivated by the identification of the blazar txs 0506+056 as the first promising high-energy neutrino counterpart candidate, we search for additional neutrino blazar candidates among the fermi-large area telescope detected blazars. we investigate the multiwavelength behavior from radio to gev gamma-rays of blazars fou... | patterns in the multiwavelength behavior of candidate neutrino blazars |
detection of the fluctuations in a 21 cm line emission from neutral hydrogen during the epoch of reionization in thousand hour integrations poses stringent requirements on calibration and image quality, both of which necessitate accurate primary beam models. the murchison widefield array (mwa) uses phased-array antenna... | measuring phased-array antenna beampatterns with high dynamic range for the murchison widefield array using 137 mhz orbcomm satellites |
context. the milky way is surrounded by large amounts of diffuse gaseous matter that connects the stellar body of our galaxy with its large-scale local group (lg) environment.aims: to characterize the absorption properties of this circumgalactic medium (cgm) and its relation to the lg we present the so-far largest surv... | an hst/cos legacy survey of high-velocity ultraviolet absorption in the milky way's circumgalactic medium and the local group |
context. although studying outflows in the host galaxies of active galactic nuclei (agns) have moved to the forefront of extragalactic astronomy in recent years, estimating the energy associated with these outflows has been a major challenge. determining the energy associated with an outflow often involves an assumptio... | spatially resolved electron density in the narrow line region of z < 0.02 radio agns |
we report on observations of 68 satellites belonging to the spacex starlink constellation with the lofar radio telescope. radiation associated with starlink satellites was detected at observing frequencies between 110 and 188 mhz, which is well below the 10.7- 12.7 ghz radio frequencies used for the downlink communicat... | unintended electromagnetic radiation from starlink satellites detected with lofar between 110 and 188 mhz |
the next-generation event horizon telescope (ngeht) will be a significant enhancement of the event horizon telescope (eht) array, with ∼10 new antennas and instrumental upgrades of existing antennas. the increased uv-coverage, sensitivity, and frequency coverage allow a wide range of new science opportunities to be exp... | the ngeht analysis challenges |
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