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the relation between mass and concentration of galaxy clusters traces their formation and evolution. massive lensing clusters were observed to be overconcentrated and following a steep scaling in tension with predictions from the concordance λ cold dark matter (λcdm) paradigm. we critically revise the relation in the c... | the mass-concentration relation in lensing clusters: the role of statistical biases and selection effects |
we introduce a new parameter λds to quantify the dynamical state of galaxy clusters and test it using simulations from the three hundred cluster zoom suite. λds is a combination of three previously used dynamical state measures, namely virial ratio, centre of mass offset, and substructure mass fraction, crafted to assu... | the three hundred: cluster dynamical states and relaxation period |
one of the hottest questions in the cosmology of self-interacting dark matter (sidm) is whether scatterings can induce detectable core-collapse in halos by the present day. because gravitational tides can accelerate core-collapse, the most promising targets to observe core-collapse are satellite galaxies and subhalo sy... | till the core collapses: the evolution and properties of self-interacting dark matter subhalos |
we compare subhalo mass and velocity functions obtained from different simulations with different subhalo finders among each other, and with predictions from the new semi-analytical model presented in paper i. we find that subhalo mass functions (shmfs) obtained using different subhalo finders agree with each other at ... | statistics of dark matter substructure - ii. comparison of model with simulation results |
dark matter substructures are interesting since they can reveal the properties of dark matter. collisionless n-body simulations of cold dark matter show more substructures compared with the population of dwarf galaxy satellites observed in our local group. therefore, understanding the population and property of subhalo... | hunting for dark matter subhalos in strong gravitational lensing with neural networks |
substructures are known to be good tracers for the dynamical states and recent accretion histories of the most massive collapsed structures in the universe, galaxy clusters. observations find extremely massive substructures in some clusters, especially abell 2744 (a2744), which are potentially in tension with the λcdm ... | the hateful eight: connecting massive substructures in galaxy clusters like a2744 to their dynamical assembly state using the magneticum simulations |
we introduce phew ( parallel hi erarchical watershed), a new segmentation algorithm to detect structures in astrophysical fluid simulations, and its implementation into the adaptive mesh refinement (amr) code ramses. phew works on the density field defined on the adaptive mesh, and can thus be used on the gas density o... | phew: a parallel segmentation algorithm for three-dimensional amr datasets. application to structure detection in self-gravitating flows |
detecting substructure within strongly lensed images is a promising route to shed light on the nature of dark matter. however, it is a challenging task, which traditionally requires detailed lens modeling and source reconstruction, taking weeks to analyze each system. we use machine-learning to circumvent the need for ... | extracting the subhalo mass function from strong lens images with image segmentation |
understanding the non-linear dynamics of satellite haloes (a.k.a. 'sub-haloes') is important for predicting the abundance and distribution of dark matter sub-structures and satellite galaxies, and for distinguishing among microphysical dark matter models using observations. typically, modelling these dynamics requires ... | a new calibration method of sub-halo orbital evolution for semi-analytic models |
a few dark matter substructures have recently been detected in strong gravitational lenses through their perturbations of highly magnified images. we derive a characteristic scale for lensing perturbations and show that they are significantly larger than the perturber’s einstein radius. we show that the perturber’s pro... | a robust mass estimator for dark matter subhalo perturbations in strong gravitational lenses |
we investigate the morphology of the stellar distribution (sd) in a sample of milky way-like galaxies in the tng50 simulation. using a local in shell iterative method as the main approach, we explicitly show evidence of twisting (in about 52% of halos) and stretching (in 48% of them) in real space. this is matched with... | inferring the morphology of stellar distribution in tng50: twisted and twisted-stretched shapes |
we present a high-resolution dissection of the two-dimensional total mass distribution in the core of the hubble frontier fields galaxy cluster macs j0416.1-2403, at z = 0.396. we exploit hst/wfc3 near-ir (f160w) imaging, vlt/multi unit spectroscopic explorer spectroscopy, and chandra data to separate the stellar, hot ... | mass profile decomposition of the frontier fields cluster macs j0416-2403: insights on the dark-matter inner profile |
cold dark matter scenarios of hierarchical large-scale structure formation predict the existence of abundant subhalos around large galaxies. however, the number of observed dwarf galaxies is far from this theoretical prediction, suggesting that most of the subhalos could be dark or quite faint. gravitational lensing is... | anomalies in time delays of lensed gravitational waves and dark matter substructures |
we present a dynamical measurement of the tangential motion of the andromeda system, the ensemble consisting of the andromeda galaxy (m31) and its satellites. the system is modelled as a structure with cosmologically motivated velocity dispersion and density profiles, and we show that our method works well when tested ... | the transverse velocity of the andromeda system, derived from the m31 satellite population |
dark matter-only simulations are able to produce the cosmic structure of a lambda cold dark matter universe, at a much lower computational cost than more physically motivated hydrodynamical simulations. however, it is not clear how well smaller substructure is reproduced by dark matter-only simulations. to investigate ... | the three hundred project: substructure in hydrodynamical and dark matter simulations of galaxy groups around clusters |
we present a morphological study of the 17 lensed lyα emitter (lae) galaxies of the baryon oscillation spectroscopic survey emission-line lens survey (bells) for the galaxy-lyα emitter systems (bells gallery) sample. this analysis combines the magnification effect of strong galaxy-galaxy lensing with the high resolutio... | the boss emission-line lens survey. v. morphology and substructure of lensed lyα emitters at redshift z ≈ 2.5 in the bells gallery |
we study the mutual relationship between dark matter-electron scattering experiments and possible new dark matter substructure nearby hinted by the gaia data. we show how kinematic substructure could affect the average and modulation spectra of dark matter-electron scattering in semiconductors and the discovery reaches... | dark matter substructure under the electron scattering lamppost |
we use a semi-analytical model for the substructure of dark matter haloes to assess the too big to fail (tbtf) problem. the model accurately reproduces the average subhalo mass and velocity functions, as well as their halo-to-halo variance, in n-body simulations. we construct thousands of realizations of milky way (mw)... | comprehensive assessment of the too big to fail problem |
we investigate a recent claim that observed galaxy clusters produce an order of magnitude more galaxy-galaxy strong lensing (ggsl) than simulated clusters in a λ cold dark matter (cdm) cosmology. we take galaxy clusters from the c-eagle hydrodynamical simulations and calculate the expected amount of ggsl for sources pl... | the galaxy-galaxy strong lensing cross-sections of simulated λcdm galaxy clusters |
in [1], kallosh and linde drew attention to a new family of superconformal inflationary potentials, subsequently called α-attractors [2]. the α-attractor family can interpolate between a large class of inflationary models. it also has an important theoretical underpinning within the framework of supergravity. we demons... | sourcing dark matter and dark energy from α-attractors |
macs j0717 is the most massive and extended of the hubble frontier field clusters. it is one of the more difficult clusters to model, and we argue that this is, in part, due to the line-of-sight structure (los) at redshifts beyond 2. we show that the grale mass reconstruction based on sources at 3 < zs < 4.1 has ... | evidence for the line-of-sight structure in the hubble frontier field cluster, macsj0717.5+3745 |
the massive substructures found in abell 2744 by jauzac et al. present a challenge to the cold dark matter paradigm due to their number and proximity to the cluster centre. we use one of the biggest n-body simulations, the millennium xxl, to investigate the substructure in a large sample of massive dark matter haloes. ... | abell 2744: too much substructure for λcdm? |
we report the serendipitous discovery of the first gravitationally lensed quasar candidate from pan-starrs. the grizy images reveal four point-like images with magnitudes between 14.9 and 18.1 mag. the colors of the point sources are similar, and they are more consistent with quasars than with stars or galaxies. the le... | discovery of the first quadruple gravitationally lensed quasar candidate with pan-starrs |
a promising route for revealing the existence of dark matter structures on mass scales smaller than the faintest galaxies is through their effect on strong gravitational lenses. we examine the role of local, lens-proximate clustering in boosting the lensing probability relative to contributions from substructure and un... | out of sight, out of mind? the impact of correlated clustering in substructure lensing |
galaxies and the dark matter haloes that host them are not spherically symmetric, yet spherical symmetry is a helpful simplifying approximation for idealized calculations and analysis of observational data. the assumption leads to an exact conservation of angular momentum for every particle, making the dynamics unreali... | milking the spherical cow - on aspherical dynamics in spherical coordinates |
we perform a set of cosmological simulations of structure formation in a mixed dark matter (mdm) model. our model is motivated by the recently identified 3.5 kev x-ray line, which can be explained by the decay of non-resonantly produced sterile neutrinos accounting for 20-60% of the dark matter in the universe. these n... | structure formation in a mixed dark matter model with decaying sterile neutrino: the 3.5 kev x-ray line and the galactic substructure |
gravitational lensing is a powerful tool for constraining substructure in the mass distribution of galaxies, be it from the presence of dark matter sub-haloes or due to physical mechanisms affecting the baryons throughout galaxy evolution. such substructure is hard to model and is either ignored by traditional, smooth ... | quantifying the structure of strong gravitational lens potentials with uncertainty-aware deep neural networks |
cluster mergers are an important laboratory for studying the behaviour of dark matter (dm) and intracluster gas. there are dissociative collisions that can separate the intracluster gas from the dm. abell 2034 presents clear dissociative features observed by x-rays and gravitational lensing. the cluster, at z = 0.114, ... | simulations of the merging galaxy cluster abell 2034: what determines the level of separation between gas and dark matter |
we use cosmological n-body simulations from the aquarius project to study the tidal effects of a dark matter halo on the shape and orientation of its substructure. although tides are often assumed to enhance asphericity and to stretch subhaloes tangentially, these effects are short lived: as in earlier work, we find th... | galactic tides and the shape and orientation of dwarf galaxy satellites |
strongly lensed systems are powerful probes of the distribution of dark matter on small scales. in this paper, we show that line-of-sight haloes between the source and the observers give rise to a distinct anisotropic signature in the two-point function of the effective lensing deflection field. we show in particular t... | interlopers speak out: studying the dark universe using small-scale lensing anisotropies |
the structural properties of individual dark matter haloes, including shape, spin, concentration, and substructure, are linked to the halo's growth history, but the exact connection between the two is unclear. one open question, in particular, is the effect of major mergers on halo structure. we have performed a large ... | major mergers between dark matter haloes - i. predictions for size, shape, and spin |
in this article we present the dark-photons&axion-like particles interferometer (dali), a novel experiment designed for the detection of photon-mixing cold dark matter in the microwave band between 6 and 60 ghz. dali is a haloscope for the simultaneous search for axions, axion-like particles and dark photons, with ... | a dark matter telescope probing the 6 to 60 ghz band |
the positions of multiple images in galaxy lenses are related to the galaxy mass distribution. smooth elliptical mass profiles were previously shown to be inadequate in reproducing the quad population. in this paper, we explore the deviations from such smooth elliptical mass distributions. unlike most other work, we us... | the impact of λcdm substructure and baryon-dark matter transition on the image positions of quad galaxy lenses |
dark matter (dm) direct detection experiments aim to place constraints on the dm-nucleon scattering cross-section and the dm particle mass. these constraints depend sensitively on the assumed local dm density and velocity distribution function. while astrophysical observations can inform the former (in a model-dependen... | informing dark matter direct detection limits with the artemis simulations |
we show that the mass of a dark matter halo can be inferred from the dynamical status of its satellite galaxies. using nine dark matter simulations of halos like the milky way (mw), we find that the present-day substructures in each halo follow a characteristic distribution in the phase space of orbital binding energy ... | determination of dark matter halo mass from dynamics of satellite galaxies |
we simulate tidal streams in the presence and absence of substructures inside the zero-redshift snapshot of the via lactea ii (vl-2) simulation. a halo finder is used to remove and isolate the subhalos found inside the high-resolution dark matter halo of vl-2, and the potentials for both the main halo and all the subha... | simulating tidal streams in a high-resolution dark matter halo |
in this second paper, we present the first n-body cosmological simulations of strongly coupled dark energy (scdew) models, a class of models that alleviates theoretical issues related to the nature of dark energy (de). scdew models assume a strong coupling between de and an ancillary cold dark matter (cdm) component to... | strongly coupled dark energy cosmologies: preserving λcdm success and easing low-scale problems - ii. cosmological simulations |
a large population of extended substructures generates a stochastic gravitational field that is fully specified by the function p(f), which defines the probability that a tracer particle experiences a force f within the interval f, f+d{f}. this paper presents a statistical technique for deriving the spectrum of random ... | fluctuations of the gravitational field generated by a random population of extended substructures |
we present an analysis of archival observations with the atacama large (sub-)millimetre array (alma) of the gravitationally lensed quasar mg j0414+0534, which show four compact images of the quasar and an einstein ring from the dust associated with the quasar host galaxy. we confirm that the flux-ratio anomalies observ... | a flux-ratio anomaly in the co spectral line emission from gravitationally lensed quasar mg j0414+0534 |
paleodetectors are a proposed experimental technique to search for dark matter by reading out the damage tracks caused by nuclear recoils in small samples of natural minerals. unlike a conventional real-time direct detection experiment, paleodetectors have been accumulating these tracks for up to a billion years. these... | galactic geology: probing time-varying dark matter signals with paleodetectors |
to provide a quantitative cosmological context to ongoing observational work on the formation histories and location of compact massive galaxies, we locate and study a sample of exceptionally compact systems in the bolshoi simulation, using the dark matter structural parameters from a real, compact massive galaxy (ngc ... | a cosmological context for compact massive galaxies |
we study the evolution of the dark matter (dm) halo profiles of dwarf galaxies driven by the accretion of dm substructures through controlled n-body experiments. our initial conditions assume that early supernova feedback erases the primordial dm cusps of haloes with z = 0 masses of 109 - 1010 m⊙. the orbits and masses... | under the sword of damocles: plausible regeneration of dark matter cusps at the smallest galactic scales. |
we present the first strong-gravitational-lensing analysis of the galaxy cluster rx j0437.1+0043 (rxj0437; z = 0.285). newly obtained, deep muse observations, keck/mosfire near-infrared spectroscopy, and hubble space telescope snapshot imaging reveal 13 multiply imaged background galaxies, three of them (at z = 1.98, 2... | rxj0437+00: constraining dark matter with exotic gravitational lenses |
strong gravitationally lensed arcs produced by galaxy clusters have been observationally detected for several decades now. these strong lensing constraints provided high-fidelity mass models for cluster lenses that include substructure down to $10^{9{-}10}\, \mathrm{m}_\odot$. optimizing lens models, where the cluster ... | detecting low-mass perturbers in cluster lenses using curved arc bases |
the observational features of the massive galaxy cluster “el gordo” (act-cl j0102-4915), such as the x-ray emission, the sunyaev-zel’dovich (sz) effect, and the surface mass density distribution, indicate that they are caused by an exceptional ongoing high-speed collision of two galaxy clusters, similar to the well-kno... | simulating the galaxy cluster “el gordo” and identifying the merger configuration |
a fundamental prediction of the cold dark matter cosmology is the existence of a large number of dark subhalos around galaxies, most of which should be entirely devoid of stars. confirming the existence of dark substructures stands among the most important empirical challenges in modern cosmology: if they are found and... | through a smoother lens: an expected absence of lcdm substructure detections from hydrodynamic and dark matter only simulations |
this article reports on a search for dark matter pair production in association with a higgs boson decaying to a pair of bottom quarks, using data from 20.3 fb-1 of p p collisions at a center-of-mass energy of 8 tev collected by the atlas detector at the lhc. the decay of the higgs boson is reconstructed as a high-mome... | search for dark matter produced in association with a higgs boson decaying to two bottom quarks in p p collisions at √{s }=8 tev with the atlas detector |
a clean measurement of the evolution of the galaxy cluster mass function can significantly improve our understanding of cosmology from the rapid growth of cluster masses below z < 0.5. here, we examine the consistency of cluster catalogues selected from the sloan digital sky survey by applying two independent gravit... | comparing gravitational redshifts of sdss galaxy clusters with the magnified redshift enhancement of background boss galaxies |
we introduce a method for producing a galaxy sample unbiased by surface brightness and stellar mass, by selecting star-forming galaxies via the positions of core-collapse supernovae (ccsne). whilst matching ∼2400 supernovae from the sdss-ii supernova survey to their host galaxies using iac stripe 82 legacy coadded imag... | the galaxy stellar mass function and low surface brightness galaxies from core-collapse supernovae |
we study structure formation in a set of cosmological simulations to uncover the scales in the initial density field that gave rise to the formation of present-day structures. our simulations share a common primordial power spectrum (here λ cold dark matter, λcdm), but the introduction of hierarchical variations of the... | setting the stage: structures from gaussian random fields |
the galaxy distribution in dark matter-dominated halos is expected to approximately trace the details of the underlying dark matter substructure. in this paper we introduce halo `core-tracking' as a way to efficiently follow the small-scale substructure in cosmological simulations and apply the technique to model the g... | modeling the galaxy distribution in clusters using halo cores |
in this paper, the recently proposed mass dimension one fermionic field is supposed to be responsible for the dark matter (dm) halo around galactic nuclei, through the quantum degeneracy pressure effect of the field. it will be shown that the mass-ratio relation for dwarf galaxies can be well explained for a particle d... | degeneracy pressure of mass dimension one fermionic fields and the dark matter halo of galaxies |
we constrain the mass of the milky way´s dark matter halo, based on the kinematics of 9627 k giants at galactocentric distances ranging over 5 kpc < r< 120 {kpc} drawn from lamost dr5. the substructure in this sample has been identified and removed carefully to enable construction of the underlying line-of-sight ... | the mass of the galactic dark matter halo from ∼9000 lamost dr5 k giants |
we recommend a deeper extension to the high-latitute wide area survey planned to be conducted by the nancy grace roman space telescope (\emph{roman}). while this deeper-tier survey extension can support a range of astrophysical investigations, it is particularly well suited to characterize the dark matter substructure ... | searching for dark matter substructure: a deeper wide-area community survey for roman |
galaxy-scale strongly lensed systems have been shown to provide a unique technique for exploring the underlying physics of dark matter at sub-galactic scales. in the past, much attention was given to detecting and studying individual haloes in a strong lens system. in addition to the subhaloes, line-of-sight haloes con... | anisotropic strong lensing as a probe of dark matter self-interactions |
we present the results of a multiwavelength investigation of the very x-ray luminous galaxy cluster macsj0553.4-3342 (z = 0.4270; hereafter macsj0553). combining high-resolution data obtained with the hubble space telescope and the chandra x-ray observatory with ground-based galaxy spectroscopy, our analysis establishe... | fully stripped? the dynamics of dark and luminous matter in the massive cluster collision macsj0553.4-3342 |
hierarchical models of structure formation predict that dark matter halo assembly histories are characterized by episodic mergers and interactions with other haloes. an accurate description of this process will provide insights into the dynamical evolution of haloes and the galaxies that reside in them. using large cos... | extracting galaxy merger time-scales - i. tracking haloes with wherewolf and spinning orbits with orbweaver |
the information about the mass density of galaxy clusters provided by the gravitational lens effect has inspired many inversion techniques. in this article, updates to the previously introduced method in grale are described, and explored in a number of examples. the first looks into a different way of incorporating tim... | extended lens reconstructions with grale: exploiting time-domain, substructural, and weak lensing information |
forthcoming large-scale spectroscopic surveys will soon provide data on thousands of galaxy clusters. it is important that the systematics of the various mass estimation techniques is well understood and calibrated. we compare three different dynamical mass estimators using the c-eagle galaxy clusters, a set of high-re... | the cluster-eagle project: a comparison of dynamical mass estimators using simulated clusters |
lcdm is remarkably successful in predicting the cosmic microwave background and large-scale structure, and lcdm parameters have been determined with only mild tensions between different types of observations. hydrodynamical simulations starting from cosmological initial conditions are increasingly able to capture the c... | cosmological structure formation |
recent studies found the densities of dark matter (dm) subhaloes which surround nearby dwarf spheroidal galaxies (dsphs) to be significantly lower than those of the most massive subhaloes expected around milky way-sized galaxies in cosmological simulations, the so-called too-big-to-fail (tbtf) problem. a caveat of prev... | re-examining the too-big-to-fail problem for dark matter haloes with central density cores |
galaxy clusters constitute powerful cosmological probes thanks to comparisons between observed and simulated clusters. as such virgo constitutes a formidable source for detailed observations facilitated by its proximity. however, the diversity of clusters complicates the comparisons on a one-to-one basis. simulated clu... | virgo: an unlikely cluster of galaxies because of its environment |
understanding local stellar kinematic substructures in the solar neighbourhood helps build a complete picture of the formation of the milky way, as well as an empirical phase space distribution of dark matter that would inform detection experiments. we apply the clustering algorithm hdbscan on the gaia early third data... | robust clustering of the local milky way stellar kinematic substructures with gaia edr3 |
using realistic cosmological simulations of milky way sized haloes, we study their dynamical state and the accuracy of inferring their mass profiles with steady-state models of dynamical tracers. we use a new method that describes the phase-space distribution of a steady-state tracer population in a spherical potential... | the orbital pdf: the dynamical state of milky way sized haloes and the intrinsic uncertainty in the determination of their masses |
we present a detailed high-resolution weak-lensing study of spt-cl j2106-5844 at z = 1.132, claimed to be the most massive system discovered at z > 1 in the south pole telescope sunyaev-zel’dovich survey. based on the deep imaging data from the advanced camera for surveys and wide field camera 3 on board the hubble ... | precise mass determination of spt-cl j2106-5844, the most massive cluster at z > 1 |
dark matter substructure can contribute significantly to local dark matter searches and may provide a large uncertainty in the interpretation of those experiments. for direct detection experiments, sub-halos give rise to an additional dark matter component on top of the smooth dark matter distribution of the host halo.... | impact of substructure on local dark matter searches |
we establish a controlled comparison between the properties of galactic stellar haloes obtained with hydrodynamical simulations and with 'particle tagging'. tagging is a fast way to obtain stellar population dynamics: instead of tracking gas and star formation, it 'paints' stars directly on to a suitably defined subset... | particle tagging and its implications for stellar population dynamics |
modelling self-gravity of collisionless fluids (e.g. ensembles of dark matter, stars, black holes, dust, and planetary bodies) in simulations is challenging and requires some force softening. it is often desirable to allow softenings to evolve adaptively, in any high-dynamic range simulation, but this poses unique chal... | novel conservative methods for adaptive force softening in collisionless and multispecies n-body simulations |
the identity of dark matter has remained surprisingly elusive. while terrestrial experiments may be able to nail down a model, an alternative method is to identify dark matter based on astrophysical or cosmological signatures. a particularly sensitive approach is based on the unique signature of dark matter substructur... | domain adaptation for simulation-based dark matter searches with strong gravitational lensing |
we introduce the galaxy replacement technique (grt) that allows us to model tidal stripping of galaxies with very high mass (m star = 5.4 × 104 m ⊙ h -1) and high spatial resolution (10 pc h -1), in a fully cosmological context, using an efficient and fast technique. the technique works by replacing multiple low-resolu... | the galaxy replacement technique (grt): a new approach to study tidal stripping and formation of intracluster light in a cosmological context |
multicomponent dark matter with self-interactions, which allows for interconversions of species, is a promising paradigm that is known to successfully and simultaneously resolve major problems of the conventional lambda cold dark matter (λcdm) cosmology at galactic and subgalactic scales. in this paper, we present n-bo... | dark matter haloes in the multicomponent model - i. substructure |
aims: the hierarchical model of structure formation is a key prediction of the λ cold dark matter model, which can be tested by studying the large-scale environment and the substructure content of massive galaxy clusters. we present here a detailed analysis of the clusters rxc j0225.9-4154, rxc j0528.9-3927, and rxc j2... | from the core to the outskirts: structure analysis of three massive galaxy clusters |
we present the first numerical simulations in coupled dark energy cosmologies with high enough resolution to investigate the effects of the coupling on galactic and subgalactic scales. we choose two constant couplings and a time-varying coupling function and we run simulations of three milky way-sized haloes (∼1012 m⊙)... | effects of coupled dark energy on the milky way and its satellites |
we present direct n-body simulations of tidally filling 30 000 m⊙ star clusters orbiting between 10 and 100 kpc in galaxies with a range of dark matter substructure properties. the time-dependent tidal force is determined based on the combined tidal tensor of the galaxy's smooth and clumpy dark matter components, the l... | modelling the effects of dark matter substructure on globular cluster evolution with the tidal approximation |
we study evolution of single subhaloes with their masses of ~109 m⊙ in a milky way-sized host halo for self-interacting dark matter (sidm) models. we perform dark-matter-only n-body simulations of dynamical evolution of individual subhaloes orbiting its host by varying self-scattering cross-sections (including a veloci... | modelling self-interacting dark matter substructures - i. calibration with n-body simulations of a milky-way-sized halo and its satellite |
this is the first of a series of three papers devoted to the study of halo substructure in hierarchical cosmologies by means of the cusp formalism. in the present paper, we derive the properties of subhaloes and diffuse dark matter (ddm) accreted on to haloes and their progenitors. specifically, we relate the ddm prese... | an accurate comprehensive approach to substructure - i. accreted subhaloes |
compact groups (cgs) of galaxies appear to be the densest galaxy systems containing a few luminous galaxies in close proximity to each other, which have a typical size of a few tens of kiloparsec in observation. on the other hand, in the modern hierarchical structure formation paradigm, galaxies are assembled and group... | compact groups of galaxies in sloan digital sky survey and lamost spectral survey. ii. dynamical properties of isolated and embedded groups |
the hubble space telescope frontier fields cluster macs j1149.6+2223 is one of the most complex merging clusters, believed to consist of four dark matter halos. we present results from deep (365 ks) chandra observations of the cluster, which reveal the most distant cold front (z = 0.544) discovered to date. in the clus... | frontier fields clusters: deep chandra observations of the complex merger macs~j1149.6+2223 |
wrapping around the milky way, the sagittarius stream is the dominant substructure in the halo. our statistical selection method has allowed us to identify 106 highly likely members of the sagittarius stream. spectroscopic analysis of metallicity and kinematics of all members provides us with a new mapping of the sagit... | selecting sagittarius: identification and chemical characterization of the sagittarius stream |
the physics beyond the standard model with parameters of the compressed spectrum is well motivated both in the theory side and with phenomenological reasons, especially related to dark matter phenomenology. in this letter, we propose a method to tag soft final state particles from a decaying process of a new particle i... | revealing the jet substructure in a compressed spectrum of new physics |
strong gravitational lensing is a unique observational tool for studying the dark and luminous mass distribution both within and between galaxies. given the presence of substructures, current strong lensing observations demand more complex mass models than smooth analytical profiles, such as power-law ellipsoids. in th... | modeling lens potentials with continuous neural fields in galaxy-scale strong lenses |
accurate estimation of the merger timescales of galaxy clusters is important for understanding the cluster merger process and further understanding the formation and evolution of the large-scale structure of the universe. in this paper, we explore a baryonic effect on the merger timescale of galaxy clusters by using hy... | a baryonic effect on the merger timescale of galaxy clusters |
we present an extensive spectroscopic follow-up campaign of 29 strong lensing (sl) selected galaxy clusters discovered primarily in the second red-sequence cluster survey (rcs-2). our spectroscopic analysis yields redshifts for 52 gravitational arcs present in the core of our galaxy clusters, which correspond to 35 dis... | vlt/magellan spectroscopy of 29 strong lensing selected galaxy clusters |
we use a catalogue of stellar binaries with wide separations (up to 1 pc) identified by the gaia satellite to constrain the presence of extended substructure within the milky way galaxy. heating of the binaries through repeated encounters with substructure results in a characteristic distribution of binary separations,... | constraining dark matter substructure with gaia wide binaries |
the hubble frontier fields (hffs) are six clusters of galaxies, all showing indications of recent mergers, which have recently been observed for lensed images. as such they are the natural laboratories to study the merging history of galaxy clusters. in this work, we explore the 2d power spectrum of the mass distributi... | quantifying substructures in hubble frontier field clusters: comparison with λcdm simulations |
to investigate the spatial distribution of the intracluster medium temperature in galaxy clusters in a quantitative way and probe the physics behind it, we analyze the x-ray spectra from a sample of 50 clusters that were observed with the chandra acis instrument over the past 15 years and measure the radial temperature... | a chandra study of temperature distributions of the intracluster medium in 50 galaxy clusters |
flux ratio anomalies in strong gravitationally lensed quasars constitute a unique way to probe the abundance of non-luminous dark matter haloes, and hence the nature of dark matter. in this paper, we identify double-imaged quasars as a statistically efficient probe of dark matter, since they are 20 times more abundant ... | exploiting flux ratio anomalies to probe warm dark matter in future large-scale surveys |
if the dark matter haloes of galaxies contain large numbers of subhaloes as predicted by the λ cold dark matter model, these subhaloes are expected to appear in strong galaxy-galaxy lens systems as small-scale perturbations in individual images. we simulate observations of multiply lensed sub-mm galaxies at z ∼ 2 as a ... | probing cold dark matter subhaloes with simulated alma observations of macrolensed sub-mm galaxies |
it was proposed that the two phenomena, wmap-planck haze and fermi bubbles, may have a common origin. in the present paper we analyze the spatial structure of the haze using the planck 2018 data release. it is found that the spatial dimensions and locations of wmap-planck haze and fermi bubbles are compatible within th... | spatial structure of the wmap-planck haze |
the cold dark matter picture predicts an abundance of substructure within the galactic halo. however, most substructures host no stars and can only be detected indirectly. stellar streams present a promising probe of this dark substructure. these streams arise from tidally stripped star clusters or dwarf galaxies, and ... | stellar streams and dark substructure: the diffusion regime |
in salvador-solé, manrique & botella (paper i), we used the confluent system of peak trajectories (cusp) formalism to derive from first principles and no single free parameter the accurate abundance and radial distribution of both diffuse dark matter (ddm) and subhaloes accreted on to haloes and their progenitors a... | an accurate comprehensive approach to substructure - ii. stripped subhaloes |
a recent comparison of the massive galaxy cluster abell 2744 with the millennium xxl (mxxl) n-body simulation has hinted at a tension between the observed substructure distribution and the predictions of λ cold dark matter (λcdm). follow-up investigations indicated that this could be due to the contribution from the ho... | uncovering substructure with wavelets: proof of concept using abell 2744 |
a change in the mass of the galaxy with time will leave its imprint on the motions of the stars, with stars having radially outward (mass-loss) or inward (mass accretion) bulk motions. here, we test the feasibility of using the mean radial motion of stars in the stellar halo to constrain the rate of change of mass in t... | can radial motions in the stellar halo constrain the rate of change of mass in the galaxy? |
deap-3600 is the largest running dark matter detector filled with liquid argon, set at snolab, in sudbury, canada, 2 km underground. the experiment holds the most stringent exclusion limit in argon for wimps above 20 gev/c2. in the most recent published analysis, the background events due to α-induced scintillation in ... | recent results from deap-3600 |
we use high-resolution, hydrodynamic, galaxy simulations from the latte suite of fire-2 simulations to investigate the inherent variation of dark matter in sub-sampled regions around the solar circle of a milky way-type analogue galaxy and its impact on direct dark matter detection. these simulations show that the bary... | gusts in the headwind: uncertainties in direct dark matter detection |
schwinn et al. have recently compared the abundance and distribution of massive substructures identified in a gravitational lensing analysis of abell 2744 by jauzac et al. and n-body simulation, and found no cluster in lambda cold dark matter (λcdm) simulation that is similar to abell 2744. schwinn et al. identified th... | resolution of the apparent discrepancy between the number of massive subhaloes in abell 2744 and λcdm |
merging galaxy clusters may provide a unique window into the behavior of dark matter and the evolution of member galaxies. to interpret these natural collider experiments, we must account for how much time has passed since pericenter passage (tsp), the maximum relative speed of the merging subclusters, merger phase (ou... | dynamical properties of merging galaxy clusters from simulated analogs |
the galactic scale challenges of dark matter such as 'missing satellite' problem and 'too big to fail' problem are the main caveats of standard model of cosmology. these challenges could be solved either by implementing the complicated baryonic physics or it could be considered as an indication to a new physics beyond ... | modified initial power spectrum and too big to fail problem |
simulations of tidal streams show that close encounters with dark matter subhaloes induce density gaps and distortions in on-sky path along the streams. accordingly, observing disrupted streams in the galactic halo would substantiate the hypothesis that dark matter substructure exists there, while in contrast, observin... | quantifying tidal stream disruption in a simulated milky way |
we study the outer regions of the milky way globular cluster ngc 7089 based on new dark energy camera observations. the resulting background-cleaned stellar density profile reveals the existence of an extended envelope. we confirm previous results that cluster stars are found out up to ~1° from the cluster's centre, wh... | on the physical size of the milky way globular cluster ngc 7089 (m2) |
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