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Paleo-Detectors for Galactic Supernova NeutrinosJun 13 2019Paleo-detectors are a proposed experimental technique in which one would search for traces of recoiling nuclei in ancient minerals. Natural minerals on Earth are as old as $\mathcal{O}(1)$ Gyr and, in many minerals, the damage tracks left by recoiling ... More
A Tip for Landscape Riders: Multi-Field Inflation Can Fulfill the Swampland Distance ConjectureJun 13 2019We study how both the swampland distance conjecture and the Lyth bound affect the parameter space of multi-field models of inflation. A generic feature of multi-field inflation is that the geodesic distance $\left[\Delta\phi\right]_\text{G}$ separating ... More
Cosmological perfect fluids in Gauss-Bonnet gravityJun 13 2019In an $n$-dimensional Friedmann-Robertson-Walker metric, it is rigorously shown that any smooth theory of gravity $f(R,{\cal G})$, where $R$ is the curvature scalar and $\cal G$ is the Gauss-Bonnet topological invariant, can be associated to a perfect-fluid ... More
Primordial dark matter halos from fifth-forcesJun 12 2019We argue that primordial dark matter halos could be generated during radiation domination by long range attractive forces stronger than gravity. In this paper we derive the conditions under which these structures could dominate the dark matter content ... More
Signatures of stellar accretion in MaNGA early-type galaxiesJun 12 2019The late assembly of massive galaxies is thought to be dominated by stellar accretion in their outskirts (beyond 2 effective radii Re) due to dry, minor galaxy mergers. We use observations of 1010 passive early-type galaxies (ETGs) within z<0.15 from ... More
A model-independent characterisation of strong gravitational lensing by observablesJun 12 2019When light from a distant source object, like a galaxy or a supernova, travels towards us, it is deflected by massive objects that lie on its path. When the mass density of the deflecting object exceeds a certain threshold, multiple, highly distorted ... More
The Odd-Parity Galaxy BispectrumJun 12 2019The galaxy bispectrum contains a wealth of information about the early universe, gravity, as well as astrophysics such as galaxy bias. In this paper, we study the parity-odd part of the galaxy bispectrum which is hitherto unexplored. In the standard cosmological ... More
On the kinematics of large-scale peculiar motionsJun 12 2019We consider the linear kinematics of large-scale peculiar motions in a perturbed Friedmann universe. In so doing, we introduce a 4-velocity "tilt", relative to the smooth Hubble expansion, and take the view point of the "real" observes that move along ... More
A phase of confined electroweak force in the early UniverseJun 12 2019We consider a modified cosmological history in which the presence of beyond-the-Standard-Model physics causes the weak gauge sector, $\mathrm{SU}(2)_L$, to confine before it is Higgsed. Under the assumption of chiral symmetry breaking, quark and lepton ... More
Lensing anomalies from the epoch of reionisationJun 12 2019Reionisation blurring is a non-linear correction to the cosmic microwave background that acts similar to weak gravitational lensing and that can be computed from linear perturbations through a blurring potential. Its impact on the cosmic microwave background ... More
Coordinate independent approach to the calculation of the effects of local structure on the luminosity distanceJun 12 2019Local structure can have important effects on luminosity distance observations, which could for example affect the local estimation of the Hubble constant based on low red-shift type Ia supernovae. Using a spherically symmetric exact solution of the Eistein's ... More
Primordial Extremal Black Holes as Dark MatterJun 11 2019We show that primordial (nearly) extremal black holes with a wide range of masses from the Planck scale to around $10^9$ g could be cosmologically stable and explain dark matter, given a dark electromagnetism and a heavy dark electron. For individual ... More
Generalized Proca and its Constraint AlgebraJun 11 2019We reconsider the construction of general derivative self-interactions for a massive Proca field. The constructed Lagrangian is such that the vector field propagates at most three degrees of freedom, thus avoiding the ghostly nature of a fourth polarisation. ... More
CMB foreground measurements through broad-band radio spectro-polarimetry: prospects of the SKA-MPG telescopeJun 11 2019Precise measurement of the foreground synchrotron emission, which contaminates the faint polarized cosmic microwave background radiation (CMB), is a major challenge for the next-generation of CMB experiments. To address this, dedicated foreground measurement ... More
Constraining primordial black hole masses with the isotropic gamma ray backgroundJun 11 2019Primordial black holes can represent all or most of the dark matter in the window $10^{17}-10^{22}\,$g. Here we present an extension of the constraints on PBHs of masses $10^{13}-10^{18}\,$g arising from the isotropic diffuse gamma ray background. Primordial ... More
Distinguishing cosmologies using the turn-around radius near galaxy clustersJun 11 2019Outside galaxy clusters the competition between the inwards gravitational attraction and the outwards expansion of the Universe leads to a special radius of velocity cancellation, which is called the turn-around radius. Measurements of the turn-around ... More
Inquiring into the nature of the Abell 2667 Brightest Cluster Galaxy: physical properties from MUSEJun 11 2019Based on HST and MUSE data, we probe the stellar and gas properties (i.e. kinematics, stellar mass, star formation rate) of the radio-loud brightest cluster galaxy (BCG) located at the centre of the X-ray luminous cool core cluster Abell 2667 (z = 0.2343). ... More
Constraining primordial non-Gaussianity using two galaxy surveys and CMB lensingJun 11 2019Next-generation galaxy surveys will be able to measure perturbations on scales beyond the equality scale. On these ultra-large scales, primordial non-Gaussianity leaves signatures that can shed light on the mechanism by which perturbations in the early ... More
B-mode TargetsJun 11 2019The CMB-S4 Science Book, Astro2020 Science White Paper on gravitational waves, and PICO report contain an extensive discussion of many ongoing and planned efforts in the search for gravitational waved produced by inflation. Here we give a short executive ... More
Euclid preparation III. Galaxy cluster detection in the wide photometric survey, performance and algorithm selectionJun 11 2019Galaxy cluster counts in bins of mass and redshift have been shown to be a competitive probe to test cosmological models. This method requires an efficient blind detection of clusters from surveys with a well-known selection function and robust mass estimates. ... More
Leptogenesis after superconformal subcritical hybrid inflationJun 11 2019We consider an extended version of superconformal subcritical hybrid inflation model by introducing three right-handed neutrinos that have Majorana mass terms. In the model one of the right-handed sneutrinos plays a role of the inflaton field, and it ... More
Observational Tests of Gauss-Bonnet Like Dark Energy ModelJun 11 2019The consistency of some dynamical dark energy models based on Gauss-Bonnet invariant, ${\cal G}$, is studied compared with cosmological observational tests. The investigated models are modified form of Gauss Bonnet dark energy, MGB-DE and two other versions ... More
A cosmic shadow on CSLJun 11 2019The Continuous Spontaneous Localisation (CSL) model solves the measurement problem of standard quantum mechanics, by coupling the mass density of a quantum system to a white-noise field. Since the mass density is not uniquely defined in general relativity, ... More
Top-Hat Spherical Collapse with Clustering Dark Energy. I. Radius Evolution and Critical Contrast DensityJun 11 2019Understanding the influence of dark energy on the formation of structures is currently a major challenge in Cosmology, since it can distinguish otherwise degenerated viable models. In this work we consider the Top-Hat Spherical-Collapse (SC) model with ... More
Extensions to the halo occupation distribution model for more accurate clustering predictionsJun 10 2019We test different implementations of the halo occupation distribution (HOD) model to reconstruct the spatial distribution of galaxies as predicted by a publicly available semi-analytical model (SAM). We compare the measured two-point correlation functions ... More
Tests of Acoustic Scale Shifts in Halo-based Mock Galaxy CataloguesJun 10 2019We utilise mock catalogues from high-accuracy cosmological $N$-body simulations to quantify shifts in the recovery of the acoustic scale that could potentially result from galaxy clustering bias. The relationship between galaxies and dark matter halos ... More
Ultra light Thomas-Fermi Dark MatterJun 10 2019We investigate the viability of a simple dark matter (DM) model consisting of a single fermion in the context of galactic dynamics. We use a consistent approach that does not presume a particular DM density profile but instead requires that the DM+baryon ... More
Forecasted constraints on modified gravity from Sunyaev Zel'dovich tomographyJun 10 2019Observational cosmology has become an important laboratory for testing General Relativity, with searches for modified gravity forming a significant portion of the science case for existing and future surveys. In this paper, we illustrate how future measurements ... More
Dark matter capture in celestial objects: Improved treatment of multiple scattering and updated constraints from white dwarfsJun 10 2019We revisit dark matter (DM) capture in celestial objects, including the impact of multiple scattering, and obtain updated constraints on the DM-proton cross section using observations of white dwarfs. Considering a general form for the energy loss distribution ... More
Any extremal black holes are primordialJun 10 2019Extremal Kerr black holes, if they exist, cannot have an astrophysical origin due to the Thorne limit $a<a^*_{\rm lim}=0.998$. However this limit can be evaded if they are primordial and subject to evaporation by Hawking radiation. We derive the lower ... More
Challenging bulk viscous unified scenarios with cosmological observationsJun 10 2019In a spatially flat Friedmann-Lema\^{i}tre-Robertson-Walker universe, we investigate a unified cosmic fluid scenario endowed with bulk viscosity in which the coefficient of the bulk viscosity has a power law evolution. The power law in the bulk viscous ... More
Testing dark energy models with a new sample ofstrong-lensing systemsJun 10 2019Inspired by a new compilation of strong lensing systems (SLS), which consist of 205 points in the redshift range $0.0625< z_{l} < 0.958$ for the lens galaxy and $0.196< z_{s} < 3.595$ for the source, we constrain three models that generate a late cosmic ... More
Unique contributions to the scalar bispectrum in `just enough inflation'Jun 10 2019A scalar field rolling down a potential with a large initial velocity results in inflation of a finite duration. Such a scenario suppresses the scalar power on large scales improving the fit to the cosmological data. We find that the scenario leads to ... More
Dynamics of Einstein-Aether Scalar field CosmologyJun 10 2019We study the cosmological evolution of the field equations in the context of Einstein-Aether cosmology by including a scalar field in a spatially flat Friedmann--Lema\^{\i}tre--Robertson--Walker spacetime. Our analysis is separated into two separate where ... More
Testing the weak equivalence principle by differential measurements of fundamental constants in the Magellanic CloudsJun 09 2019Non-standard fields are assumed to be responsible for phenomena attributed to dark energy and dark matter. Being coupled to ordinary matter, these fields modify the masses and/or charges of the elementary particles, thereby violating the Weak Equivalence ... More
Signatures of relic quantum nonequilibriumJun 09 2019[Shortened Abstract:] This thesis explores the possibility that quantum probabilities arose thermodynamically. A chief concern is the detection of primordial `quantum nonequilibrium', since this is observably distinct from textbook quantum physics. Chapters ... More
The biasing phenomenonJun 09 2019{We study biasing as a physical phenomenon by analysing geometrical and clustering properties of density fields of matter and galaxies.} {Our goal is to determine the bias function using a combination of geometrical and power spectrum analysis of simulated ... More
Testing Inflationary CosmologyJun 09 2019In this thesis we will primarily demonstrate how additional scalar degrees of freedom - which are motivated from many high-energy embeddings - open up new observational windows onto the physics of inflation. We construct a Bayesian framework to statistically ... More
The Impact of the Fiducial Cosmology Assumption on BAO Cosmological Parameter InferenceJun 07 2019Standard analysis pipelines for measurements of Baryon Acoustic Oscillations (BAO) in galaxy surveys make use of a fiducial cosmological model to guide the data compression required to transform from observed redshifts and angles to the measured angular ... More
The Redshift Space Momentum Power Spectrum II: measuring the growth rate from the combined 2MTF and 6dFGSv surveysJun 07 2019Measurements of the growth rate of structure, $f\sigma_8$ in the low-redshift Universe allow stringent tests of the cosmological model. In this work, we provide new constraints on $f\sigma_{8}$ at an effective redshift of $z=0.03$ using the combined density ... More
On Stochastic Effects and Primordial Black-Hole FormationJun 06 2019The effect of large quantum fluctuations on primordial black-hole formation during an inflationary phase along a plateau is investigated. By using techniques of stochastic inflation in combination with replica field theory and the Feynman-Jensen variational ... More
On the road to per cent level accuracy II: calibration of the non-linear matter power spectrum for arbitrary cosmologiesJun 06 2019We introduce an emulator approach to predict the non-linear matter power spectrum for broad classes of beyond-$\Lambda$CDM cosmologies, using only a suite of $\Lambda$CDM $N$-body simulations. By including a range of suitably modified initial conditions ... More
Gravitational wave observations, distance measurement uncertainties, and cosmologyJun 06 2019Gravitational waves from the coalescence of compact binaries, together with an associated electromagnetic counterpart, are ideal probes of cosmological models. As demonstrated with GW170817, such multimessenger observations allow one to use the source ... More
Relativistic bubble collisions -- a closer lookJun 06 2019We study scalar bubble collisions in first-order phase transitions focusing on the relativistic limit. We propose 'trapping equation' which describes the wall behavior after collision, and test it with numerical simulations in several setups. We also ... More
Planck 2018 results. VII. Isotropy and Statistics of the CMBJun 06 2019Analysis of the Planck 2018 data set indicates that the statistical properties of the cosmic microwave background (CMB) temperature anisotropies are in excellent agreement with previous studies using the 2013 and 2015 data releases. In particular, they ... More
Higher Derivative Theory For Curvature Term Coupling With Scalar FieldJun 06 2019Higher order derivative theories, generally suffer from instabilities, known as Ostrogradsky instabilities. This issue can be resolved by removing any existing degeneracy present in such theories. We consider a model involving at most second order derivatives ... More
The impact of inhomogeneous subgrid clumping on cosmic reionizationJun 06 2019Cosmic reionization was driven by the imbalance between early sources and sinks of ionizing radiation, both of which were dominated by small-scale structure and are thus usually treated in cosmological reionization simulations by subgrid modelling. The ... More
SOFIA Far-infrared [O III] and [O I] Observations of Dense CO-knots in the Supernova Remnant Cassiopeia A: Multi-phase EjectaJun 06 2019Dense, fast-moving ejecta knots in supernova remnants are prime sites for molecule and dust formation. We present SOFIA far-IR spectrometer FIFI-LS observations of CO-rich knots in Cas A which cover a ~1 square arc minute area of the northern shell, in ... More
The Most Massive galaxy Clusters (M2C) across cosmic time: link between radial total mass distribution and dynamical stateJun 05 2019We study the dynamical state and the integrated total mass profiles of 75 massive (M500 > 5 e+14 M_sun) SZ-selected clusters at 0.08<z< 1.1. The sample is built from the Planck catalogue, with the addition of 4 SPT clusters at z>0.9. Using XMM imaging ... More
On the Cosmological Evolution of Long Gamma-ray Burst PropertiesJun 05 2019We examine the relationship between a number of long gamma-ray burst (lGRB) properties (isotropic emitted energy, luminosity, intrinsic duration, jet opening angle) and redshift. We find that even when accounting for conservative detector flux limits, ... More
Average Dark Matter Halo Sparsity Relations as Consistency Check of Mass Estimates in Galaxy Cluster SamplesJun 05 2019The dark matter halo sparsity provides a direct observational proxy of the halo mass profile, characterizing halos in terms of the ratio of masses within radii which enclose two different overdensities. Previous numerical simulation analyses have shown ... More
A null test to probe the scale-dependence of the growth of structure as a test of General RelativityJun 05 2019The main science driver for the coming generation of cosmological surveys is understanding dark energy which relies on testing General Relativity on the largest scales. Once we move beyond the simplest explanation for dark energy of a cosmological constant, ... More
The Warped Dark SectorJun 05 2019Five-dimensional braneworld constructions in anti-de Sitter space naturally lead to dark sector scenarios in which parts of the dark sector vanish at high 4d momentum or temperature. In the language of modified gravity, such feature implies a new mechanism ... More
Pseudo-Goldstone dark matter confronts cosmic ray and collider anomaliesJun 05 2019Persistent excesses in the spectra of gamma rays from the galactic center and cosmic ray antiprotons can be explained by dark matter of mass 50-65 GeV annihilating into $b$ quarks, but this is typically hard to reconcile with direct detection constraints. ... More
Radiative Transfer Distortions of Lyman-$α$ Emitters: a New Fingers-of-God Damping in the Clustering in Redshift SpaceJun 05 2019Complex radiative transfer (RT) of the Lyman-$\alpha$ photons poses a theoretical challenge to galaxy surveys which infer the large-scale structure with Lyman-$\alpha$ emitters (LAEs). Guided by RT simulations, prior studies investigated the impact of ... More
Radiative Transfer Distortions of Lyman-$α$ Emitters: a New Fingers-of-God Damping in the Clustering in Redshift SpaceJun 05 2019Jun 06 2019Complex radiative transfer (RT) of the Lyman-$\alpha$ photons poses a theoretical challenge to galaxy surveys which infer the large-scale structure with Lyman-$\alpha$ emitters (LAEs). Guided by RT simulations, prior studies investigated the impact of ... More
Independent Cosmological Constraints from high-z HII GalaxiesJun 05 2019We present new high spectral resolution observations of 15 high-z ($1.3 \leq$ z $\leq 2.5$) HII Galaxies (HIIG) obtained with MOSFIRE at the Keck Observatory. These data, combined with already published data for another 31 high-z and 107 z $\leq 0.15$ ... More
On hilltop and brane inflation after PlanckJun 05 2019Hilltop inflation models are often described by potentials $V = V_{0}(1-{\phi^{n}\over m^{n}}+...)$. The omitted terms indicated by ellipsis do not affect inflation for $m \lesssim 1$, but the most popular models with $n =2$ and $4$ for $m \lesssim 1$ ... More
Probing Dynamics of Boson Stars by Fast Radio Bursts and Gravitational Wave DetectionJun 05 2019Boson stars may consist of a new type of light singlet scalar particles with nontrivial self-interactions, and may compose a fraction of the dark matter in the Universe. In this work, we study the dynamics of boson stars with Liouville and logarithmic ... More
Exact enumeration approach to first-passage time distribution of non-Markov random walksJun 05 2019We propose an analytical approach to study non-Markov random walks by employing an exact enumeration method. Using the method, we derive an exact expansion for the first-passage time (FPT) distribution for any continuous, differentiable non-Markov random ... More
The Absence of [CII] 158$μ$m Emission in Spectroscopically-Confirmed Galaxies at $z>8$Jun 05 2019The scatter in the relationship between the strength of [CII] 158$\mu$m emission and the star formation rate at high-redshift has been the source of much recent interest. Although the relationship is well-established locally, several intensely star-forming ... More
Brighter-fatter effect in near-infrared detectors -- II. Auto-correlation analysis of H4RG-10 flatsJun 05 2019The Wide Field Infrared Survey Telescope (WFIRST) will investigate the origins of cosmic acceleration using weak gravitational lensing at near infrared wavelengths. Lensing analyses place strict constraints on the precision of size and ellipticity measurements ... More
Brighter-fatter effect in near-infrared detectors -- I. Theory of flat auto-correlationsJun 05 2019Weak gravitational lensing studies aim to measure small distortions in the shapes of distant galaxies, and thus place very tight demands on the understanding of detector-induced systematic effects in astronomical images. The Wide-Field Infrared Survey ... More
An experiment to search for dark matter interactions using sodium iodide detectorsJun 05 2019Observations of galaxies and primordial radiation suggest that the Universe is made mostly of non-luminous dark matter. Several types of new fundamental particles have been proposed as candidates for dark matter such as weakly interacting massive particles ... More
Status of Light Sterile Neutrino SearchesJun 04 2019A number of anomalous results in short-baseline oscillation may hint at the existence of one or more light sterile neutrino states in the eV mass range and have triggered a wave of new experimental efforts to search for a definite signature of oscillations ... More
Two merging galaxy clusters with very hot shock fronts observed shortly before pericentric passageJun 04 2019We present a detailed analysis of two merging clusters, from XMM-\textit{Newton} X-ray archival data: PLCKESZ G036.7+14.9 ($z=0.15$; hereafter G036) and PLCK G292.5+22.0 ($z=0.30$; hereafter G292). We notice that the intracluster medium is heated as a ... More
Confusion noise due to clustered extragalactic point sources. Application of logarithmic cumulants for parameter estimationJun 04 2019The calculation of the characteristic function of the signal fluctuations due to clustered astrophysical sources is performed in this paper. For the typical case of power-law differential number counts and two-point angular correlation function, we present ... More
BlueMUSE: Project Overview and Science CasesJun 04 2019We present the concept of BlueMUSE, a blue-optimised, medium spectral resolution, panoramic integral field spectrograph based on the MUSE concept and proposed for the Very Large Telescope. With an optimised transmission down to 350 nm, a larger FoV (1.4 ... More
Detailed study of the ELAIS N1 field with the uGMRT - I. Characterizing the 325 MHz foreground for redshifted 21 cm observationsJun 04 2019In this first paper of the series, we present initial results of newly upgraded Giant Meterwave Radio Telescope (uGMRT) observation of European Large-Area ISO Survey-North 1 (ELAIS-N1) at 325 MHz with 32 MHz bandwidth. Precise measurement of fluctuations ... More
And yet it flips: connecting galactic spin and the cosmic webJun 04 2019We study the spin alignment of galaxies and halos with respect to filaments and walls of the cosmic web, identified with DisPerSE, using the SIMBA simulation from z=0-2. Massive halos' spins are oriented perpendicularly to their closest filament's axis ... More
Testing modified gravity at cosmological distances with LISA standard sirensJun 04 2019Modifications of General Relativity leave their imprint both on the cosmic expansion history through a non-trivial dark energy equation of state, and on the evolution of cosmological perturbations in the scalar and in the tensor sectors. In particular, ... More
Gaussian-mixture-model-based cluster analysis of gamma-ray bursts in the BATSE catalogJun 04 2019Clustering is an important tool to describe gamma-ray bursts (GRBs). We analyzed the Final BATSE Catalog using Gaussian-mixture-models-based clustering methods for six variables (durations, peak flux, total fluence and spectral hardness ratios) that contain ... More
Formation and mass growth of axion stars in axion miniclustersJun 04 2019We study the formation and the subsequent mass growth of axion stars inside axion miniclusters. Numerically solving the Schr\"odinger-Poisson equations with realistic initial conditions we find that the axion stars exhibit similar properties to solitonic ... More
Inflation model selection revisitedJun 04 2019We update the constraints on the power spectra of primordial curvature perturbation and tensor perturbation including Planck data 2015 (P15) and recently released BICEP2/Keck data (BK15), Baryon Acoustic Oscillation data and the Type Ia supernovae data. ... More
Producing a BOSS-CMASS sample with DES imagingJun 04 2019We present a sample of galaxies with the Dark Energy Survey (DES) photometry that replicates the properties of the BOSS CMASS sample. The CMASS galaxy sample has been well characterized by the Sloan Digital Sky Survey (SDSS) collaboration and was used ... More
Absolving the SSINS of Precision Interferometric Radio Data: A New Technique for Mitigating Ultra-faint Radio Frequency InterferenceJun 03 2019We introduce a new method for mitigating ultra-faint radio frequency interference (RFI), which we call Sky-Subtracted Incoherent Noise Spectra (SSINS). SSINS is designed to identify and remove RFI below the single baseline thermal noise. We demonstrate ... More
First Results on the Search for Chameleons with the KWISP Detector at CASTJun 03 2019We report on a first measurement with a sensitive opto-mechanical force sensor designed for the direct detection of coupling of real chameleons to matter. These dark energy candidates could be produced in the Sun and stream unimpeded to Earth. The KWISP ... More
Monte Carlo Control Loops for cosmic shear cosmology with DES Year 1Jun 03 2019Weak lensing by large-scale structure is a powerful probe of cosmology and of the dark universe. This cosmic shear technique relies on the accurate measurement of the shapes and redshifts of background galaxies and requires precise control of systematic ... More
Genericness of pre-inflationary dynamics and probability of slow-roll inflation in modified loop quantum cosmologiesJun 03 2019We study the evolution of spatially flat FLRW universe for chaotic and Starobinsky potentials in the framework of modified loop quantum cosmologies. These models result in a non-singular bounce as in loop quantum cosmology, but with far more complex modified ... More
The Effective Field Theory of Large Scale Structure at Three LoopsJun 03 2019We study the power spectrum of dark matter density fluctuations in the framework of the Effective Field Theory of Large Scale Structures (EFTofLSS) up to three loop orders. In principle, several counter-terms may be needed to handle the short-distance ... More
Super heavy thermal dark matterJun 03 2019We propose a mechanism of elementary thermal dark matter with mass up to $10^{14}$ GeV, within a standard cosmological history, whose relic abundance is determined solely by its interactions with the Standard Model, without violating the perturbative ... More
The polytropic state of the intracluster medium in the X-COP cluster sampleJun 03 2019In this work, we investigate the relation between the radially-resolved thermodynamic quantities of the intracluster medium in the X-COP cluster sample, aiming to assess the stratification properties of the ICM. We model the relations between radius, ... More
The polytropic state of the intracluster medium in the X-COP cluster sampleJun 03 2019Jun 05 2019In this work, we investigate the relation between the radially-resolved thermodynamic quantities of the intracluster medium in the X-COP cluster sample, aiming to assess the stratification properties of the ICM. We model the relations between radius, ... More
On the mass mismatch between simulations and weak-lensing measurementsJun 03 2019The recently discovered discrepancy between galaxy mass measurements from weak lensing and predictions from abundance matching questions our understanding of cosmology, or of the galaxy-halo connection, or of both. We re-examined this tension by considering, ... More
Finding Strong Gravitational Lenses in the DESI DECam Legacy SurveyJun 03 2019We perform a semi-automated search for strong gravitational lensing systems in the 9,000 deg$^2$ Dark Energy Camera Legacy Survey (DECaLS), part of the DESI Legacy Imaging Surveys (Dey et al.). The combination of the depth and breadth of these surveys ... More
Early-Universe Simulations of the Cosmological AxionJun 03 2019Ultracompact dark matter (DM) minihalos at masses at and below $10^{-12}$ $M_\odot$ arise in axion DM models where the Peccei-Quinn (PQ) symmetry is broken after inflation. The minihalos arise from density perturbations that are generated from the non-trivial ... More
Exploring the effects of galaxy formation on matter clustering through a library of simulation power spectraJun 03 2019Upcoming weak lensing surveys require a detailed theoretical understanding of the matter power spectrum in order to derive accurate and precise cosmological parameter values. While galaxy formation is known to play an important role, its precise effects ... More
Very Light Asymmetric Dark MatterJun 03 2019Very light dark matter is usually taken to consist of uncharged bosons such as axion-like particles or dark photons. Here, we consider the prospect of very light, possibly even sub-eV dark matter carrying a net charge that is (approximately) conserved. ... More
Impact of kinetic and potential self-interactions on scalar dark matterJun 03 2019We consider models of scalar dark matter with a generic interaction potential and non-canonical kinetic terms of the K-essence type that are subleading with respect to the canonical term. We analyse the low-energy regime and derive, in the nonrelativistic ... More
The cross-correlation between 21cm and CMB B modes from the cosmic birefringence in existence of light scalar fieldJun 03 2019We study the cross-correlation between the 21cm and CMB B mode fluctuations which are induced by the cosmic birefringence when the non-constant scalar field couples to the electromagnetic field strength. Such multi-wavelength signals can potentially probe ... More
Constraints on axion like dark matter from compact binary systemsJun 03 2019The orbital period of compact binaries (neutron star-neutron star, neutron star-white dwarf) decay mainly due to the gravitational quadrupole radiation. The orbital period can also decay by radiation of other light particles like axions and axion like ... More
Fluctuation of the background sky in the Hubble Extremely Deep Field (XDF) and its originJun 03 2019We performed a fluctuation analysis of the Hubble Extremely Deep Field (XDF) at four optical wavelength bands and found large fluctuations that are significantly brighter than those expected for ordinary galaxies. Good cross-correlations with flat spectra ... More
Quasinormal modes of black holes in a toy-model for cumulative quantum gravityJun 03 2019The idea that quantum gravity effects might leak outside the horizon of a black hole has recently been intensively considered. In this study, we calculate the quasinormal modes as a function of the location and amplitude of a generic metric perturbation ... More
A possible s-wave annihilation for MeV dark matter with the 21-cm absorptionJun 03 2019The CMB observation sets stringent constraints on MeV dark matter (DM) annihilating into charged states/photons in s-wave, and the recent observation of the 21-cm absorption at the cosmic dawn reported by EDGES is also very strict for s-wave annihilations ... More
Nonlinear preheating with nonminimally coupled scalar fields in the Starobinsky modelJun 03 2019We study the preheating after inflation in the Starobinsky model with a nonminimally coupled scalar field $\chi$. Using the lattice simulation, we analyze the rescattering between the $\chi$ particles and the inflaton condensate, and the backreaction ... More
Accurate Modeling of the Projected Galaxy Clustering in Photometric Surveys: I. Tests with Mock CatalogsJun 03 2019We develop a novel method to explore the galaxy-halo connection using the galaxy imaging surveys by modeling the projected two-point correlation function measured from the galaxies with reasonable photometric redshift measurements. By assuming a Gaussian ... More
Vorticity, kinetic energy, and suppressed gravitational wave production in strong first order phase transitionsJun 02 2019We have performed the first 3-dimensional simulations of strong first-order thermal phase transitions in the early Universe. For deflagrations, we find that the rotational component of the fluid velocity increases as the transition strength is increased. ... More
Discovery of four cold dusty galaxies at z=3.62-5.85 in the COSMOS field: direct evidence of CMB impact on high-redshift galaxy observablesMay 31 2019We report Atacama Large Millimetre Array (ALMA) observations of four high-redshift dusty star-forming galaxy candidates selected from far-Infrared (FIR)/submm observations in the COSMOS field. We securely detect all galaxies in the continuum and spectroscopically ... More
Dynamical system analysis of generalized energy-momentum-squared gravityMay 31 2019In this work we have investigated the dynamics of a recent modification to the general theory of relativity, the energy-momentum squared gravity model $f(R,\mathbf{T^2})$, where $R$ represents the scalar curvature and $\mathbf{T^2}$ the square of the ... More
Annihilation Signatures of Hidden Sector Dark Matter Within Early-Forming MicrohalosMay 31 2019If the dark matter is part of a hidden sector with only very feeble couplings to the Standard Model, the lightest particle in the hidden sector will generically be long-lived and could come to dominate the energy density of the universe prior to the onset ... More