text
stringlengths
89
2.49k
category
stringclasses
19 values
Spectral distortions in the cosmic microwave background polarization: We compute the spectral distortions of the Cosmic Microwave Background (CMB) polarization induced by non-linear effects in the Compton interactions between CMB photons and cold intergalactic electrons. This signal is of the $y$-type and is dominated ...
astro-ph_CO
Evidence of major dry mergers at M* > 2 x 10^11 Msun from curvature in early-type galaxy scaling relations?: For early-type galaxies, the correlations between stellar mass and size, velocity dispersion, surface brightness, color, axis ratio and color-gradient all indicate that two mass scales, M* = 3 x 10^10 Msun and...
astro-ph_CO
Baryonic effects on weak-lensing two-point statistics and its cosmological implications: We develop an extension of \textit{the Halo Model} that describes analytically the corrections to the matter power spectrum due to the physics of baryons. We extend these corrections to the weak-lensing shear angular power spectr...
astro-ph_CO
Galaxy And Mass Assembly (GAMA): Spectroscopic analysis: The Galaxy And Mass Assembly (GAMA) survey is a multiwavelength photometric and spectroscopic survey, using the AAOmega spectrograph on the Anglo-Australian Telescope to obtain spectra for up to ~300000 galaxies over 280 square degrees, to a limiting magnitude of...
astro-ph_CO
Some results on the radio-SZ correlation for galaxy cluster radio halos: We present correlation results for the radio halo power in galaxy clusters with the integrated thermal Sunyaev-Zel'dovich (SZ) effect signal, including new results obtained at sub-GHz frequencies. The radio data is compiled from several published ...
astro-ph_CO
Effective dark matter power spectra in $f(R)$ gravity: Using N-body simulations, we measure the power spectrum of the effective dark matter density field, which is defined through the modified Poisson equation in $f(R)$ cosmologies. We find that when compared to the conventional dark matter power spectrum, the effectiv...
astro-ph_CO
Measuring the growth of structure with intensity mapping surveys: Line intensity mapping offers a new avenue for constraining cosmological parameters in the high redshift Universe. However measurements of the growth of structure, a sensitive probe of gravity, are affected by a well known degeneracy with astrophysical p...
astro-ph_CO
The NGC 404 Nucleus: Star Cluster and Possible Intermediate Mass Black Hole: We examine the nuclear morphology, kinematics, and stellar populations in nearby S0 galaxy NGC 404 using a combination of adaptive optics assisted near-IR integral-field spectroscopy, optical spectroscopy, and HST imaging. These observations...
astro-ph_CO
Detecting relic gravitational waves in the CMB: Optimal parameters and their constraints: The prospect of detecting relic gravitational waves (RGWs), through their imprint in the cosmic microwave background radiation, provides an excellent opportunity to study the very early Universe. In simplest viable theoretical m...
astro-ph_CO
Light Primordial Exotic Compact Objects as All Dark Matter: The radiation emitted by horizonless exotic compact objects (ECOs), such as wormholes, 2-2-holes, fuzzballs, gravastars, boson stars, collapsed polymers, superspinars etc., is expected to be strongly suppressed when compared to the radiation of black holes. If...
astro-ph_CO
Cosmology and fundamental physics with the ELT-ANDES spectrograph: State-of-the-art 19th century spectroscopy led to the discovery of quantum mechanics, and 20th century spectroscopy led to the confirmation of quantum electrodynamics. State-of-the-art 21st century astrophysical spectrographs, especially ANDES at ESO's ...
astro-ph_CO
The Massive and Distant Clusters of WISE Survey: SZ effect Verification with the Atacama Compact Array -- Localization and Cluster Analysis: The Massive and Distant Clusters of WISE Survey (MaDCoWS) provides a catalog of high-redshift ($0.7\lesssim z\lesssim 1.5$) infrared-selected galaxy clusters. However, the verif...
astro-ph_CO
The SINS survey: modeling the dynamics of z~2 galaxies and the high-z Tully-Fisher relation: We present the modeling of SINFONI integral field dynamics of 18 star forming galaxies at z ~ 2 from Halpha line emission. The galaxies are selected from the larger sample of the SINS survey, based on the prominence of ordere...
astro-ph_CO
On the stability criteria for equatorial circular orbits in Galactic Dynamics: I.Newtonian Thin Disks: We make a revision of the stability criteria for equatorial circular orbits, obtained from the epicyclic approximation, which is widely used in Newtonian models for axisymmetric galaxies. We find that, for the case ...
astro-ph_CO
Testing Gravity Using Large-Scale Redshift-Space Distortions: We use Luminous Red Galaxies from the Sloan Digital Sky Survey II to test the cosmological structure growth in two alternatives to the standard LCDM+GR cosmological model. We compare observed three-dimensional clustering in SDSS DR7 with theoretical predicti...
astro-ph_CO
Intrinsic colors and ages of extremely red elliptical galaxies at high redshift: In order to know the formation epoch of the oldest elliptical galaxies as a function of mass and observed redshift, a statistical analysis for 333 extremely red objects (EROs) classified as old galaxies (OGs) at 0.8<z<2.3 is carried out....
astro-ph_CO
Dwarf elliptical galaxies as ancient tidal dwarf galaxies: The formation of tidal dwarf galaxies (TDGs) is triggered by the encounters of already existing galaxies. Their existence is predicted from numerical calculations of encountering galaxies and is also well documented with observations. The numerical calculations...
astro-ph_CO
Cosmic Microwave Background temperature and polarization anisotropies from the large-N limit of global defects: We determine the full C_l spectra and correlation functions of the temperature and polarization anisotropies in the CMB, generated by a source modeled by the large N limit of spontaneously broken global O(N...
astro-ph_CO
Using Elliptical Galaxy Kinematics to Compare of the Strength of Gravity in Cosmological Regions of Differing Gravitational Potential -- A First Look: Various models of modified gravity invoke ``screening'' mechanisms that are sensitive to the value of the local gravitational potential. This could have observable con...
astro-ph_CO
The effects of primordial non-Gaussianity on giant-arc statistics: For over a decade, it has been debated whether the concordance LCDM model is consistent with the observed abundance of giant arcs in clusters. While previous theoretical studies have focused on properties of the lens and source populations, as well as c...
astro-ph_CO
The role of Pop III stars and early black holes in the 21cm signal from Cosmic Dawn: Modeling the 21cm global signal from the Cosmic Dawn is challenging due to the many poorly constrained physical processes that come into play. We address this problem using the semi-analytical code "Cosmic Archaeology Tool" (CAT). CA...
astro-ph_CO
Causality, initial conditions, and inflationary magnetogenesis: The post-inflationary evolution of inflation-produced magnetic fields, conventional or not, can change dramatically when two fundamental issues are accounted for. The first is causality, which demands that local physical processes can never affect superhor...
astro-ph_CO
Testing Dvali-Gabadadze-Porrati Gravity with Planck: Recently, the Planck collaboration has released the first cosmological papers providing the highest resolution, full sky, maps of the cosmic microwave background (CMB) temperature anisotropies. In this paper we study a phenomenological model which interpolates betwee...
astro-ph_CO
Confronting Models of Dwarf Galaxy Quenching with Observations of the Local Group: A number of mechanisms have been proposed to connect star-forming dwarf irregular galaxies with the formation of non-star-forming dwarf spheroidal galaxies, but distinguishing between these mechanisms has been difficult. We use the Via...
astro-ph_CO
The Copernicus Complexio: a high-resolution view of the small-scale Universe: We introduce Copernicus Complexio (COCO), a high-resolution cosmological N-body simulation of structure formation in the $\Lambda{\rm CDM}{}$ model. COCO follows an approximately spherical region of radius $\sim 17.4h^{-1}\,{\rm Mpc}$ embed...
astro-ph_CO
KiDS-450: Cosmological Constraints from Weak Lensing Peak Statistics - II: Inference from Shear Peaks using N-body Simulations: We study the statistics of peaks in a weak lensing reconstructed mass map of the first 450 square degrees of the Kilo Degree Survey. The map is computed with aperture masses directly applied...
astro-ph_CO
Curvature Perturbations Protected Against One Loop: We examine one-loop corrections from small-scale curvature perturbations to the superhorizon-limit ones in single-field inflation models, which have recently caused controversy. We consider the case where the Universe experiences transitions of slow-roll (SR) $\to$ in...
astro-ph_CO
The extraordinary mid-infrared spectral properties of FeLoBAL Quasars: We present mid-infrared spectra of six FeLoBAL QSOs at 1<z<1.8, taken with the Spitzer space telescope. The spectra span a range of shapes, from hot dust dominated AGN with silicate emission at 9.7 microns, to moderately obscured starbursts with str...
astro-ph_CO
Cosmology at the boundary of de Sitter using the dS/QFT correspondence: Using the dS/QFT correspondence in the context of inflation allows for the study of interesting, otherwise inaccessible physics. In particular, by studying inflation via its dual field theory at the boundary of the de Sitter space, it may be possib...
astro-ph_CO
Inhomogeneities in the universe: Standard models of galaxy formation predict that matter distribution is statistically homogeneous and isotropic and characterized by (i) spatial homogeneity for r<10 Mpc/h, (ii) small-amplitude structures of relatively limited size (i.e., r<100) Mpc/h and (iii) anti-correlations for r >...
astro-ph_CO
A survey of molecular gas in luminous sub-millimetre galaxies: We present the results from a survey for 12CO emission in 40 luminous sub-millimetre galaxies (SMGs), with 850um fluxes of S850 = 4 - 20 mJy, conducted with the Plateau de Bure Interferometer. We detect 12CO emission in 32 SMGs at z~1.2 - 4.1, including 16 ...
astro-ph_CO
Massive and Newly Dead: Discovery of a Significant Population of Galaxies with High Velocity Dispersions and Strong Balmer Lines at z~1.5 from Deep Keck Spectra and HST/WFC3 Imaging: We present deep Keck/LRIS spectroscopy and HST/WFC3 imaging in the rest-frame optical for a sample of eight galaxies at z~1.5 with hi...
astro-ph_CO
Multiphase Signatures of AGN Feedback in Abell 2597: We present new Chandra X-ray observations of the brightest cluster galaxy (BCG) in the cool core cluster Abell 2597. The data reveal an extensive kpc-scale X-ray cavity network as well as a 15 kpc filament of soft-excess gas exhibiting strong spatial correlation with...
astro-ph_CO
Virial halo mass function in the ${\it Planck}$ cosmology: We study halo mass functions with high-resolution $N$-body simulations under a $\Lambda$CDM cosmology. Our simulations adopt the cosmological model that is consistent with recent measurements of the cosmic microwave backgrounds with the ${\it Planck}$ satellite...
astro-ph_CO
A New Probe of the High-z BAO scale: BAO tomography With CMB $\times$ LIM-Nulling Convergence: Standard rulers such as the baryon acoustic oscillation (BAO) scale serve as workhorses for precision tests of cosmology, enabling distance measurements that probe the geometry and expansion history of our Universe. Aside f...
astro-ph_CO
The Trispectrum in the Effective Theory of Inflation with Galilean symmetry: We calculate the trispectrum of curvature perturbations for a model of inflation endowed with Galilean symmetry at the level of the fluctuations around an FRW background. Such a model has been shown to posses desirable properties such as uni...
astro-ph_CO
Bridging the gap: spectral distortions meet gravitational waves: Gravitational waves (GWs) have the potential to probe the entirety of cosmological history due to their nearly perfect decoupling from the thermal bath and any intervening matter after emission. In recent years, GW cosmology has evolved from merely being ...
astro-ph_CO
Accurate AGN black hole masses and the scatter in the M_{bh} - L_{bulge} relationship: A new empirical formulae is given for estimating the masses of black holes in AGNs from the H beta velocity dispersion and the continuum luminosity at 5100 Angstroms. It is calibrated to reverberation-mapping and stellar-dynamical ...
astro-ph_CO
H0LiCOW I. $H_0$ Lenses in COSMOGRAIL's Wellspring: Program Overview: Strong gravitational lens systems with time delays between the multiple images allow measurements of time-delay distances, which are primarily sensitive to the Hubble constant that is key to probing dark energy, neutrino physics, and the spatial curv...
astro-ph_CO
The effect of massive neutrinos on the BAO peak: We study the impact of neutrino masses on the shape and height of the BAO peak of the matter correlation function, both in real and redshift space. In order to describe the nonlinear evolution of the BAO peak we run N-body simulations and compare them with simple analyti...
astro-ph_CO
Intrinsic brightness of SDSS objects is similar at all redshifts in de Sitter space: The redshift-luminosity distributions for well-defined galaxies and quasars in the Sloan Digital Sky Survey (SDSS) are compared for the two redshift-distance relations of a Hubble redshift and a de Sitter redshift. Assuming a Hubble ...
astro-ph_CO
Observational constraints on the tilted spatially-flat and the untilted nonflat $φ$CDM dynamical dark energy inflation models: We constrain spatially-flat tilted and nonflat untilted scalar field ($\phi$) dynamical dark energy inflation ($\phi$CDM) models by using Planck 2015 cosmic microwave background (CMB) anisotr...
astro-ph_CO
Cosmic transparency and acceleration: In this paper, by considering an absorption probability independent of photon wavelength, we show that current type Ia supernovae (SNe Ia) and gamma ray burst (GRBs) observations plus high-redshift measurements of the cosmic microwave background (CMB) radiation temperature support ...
astro-ph_CO
Swift BAT, Fermi LAT, and the Blazar Sequence: Using public \fermi LAT and \swift BAT observations, we constructed the first sample of blazars selected at both hard X-rays and gamma-rays. Studying its spectral properties, we find a luminosity dependence of the spectral slopes at both energies. Specifically, luminous bl...
astro-ph_CO
B-mode in CMB polarization. What's that and why it is interesting: Generation of the B-mode of CMB polarization by background of relic gravitational wave is discussed in connection with the BICEP2 measurements. Description of the polarization maps in terms of the eigenvectors of the polarization matrix is considered.
astro-ph_CO
Post-Planck Dark Energy Constraints: We constrain plausible dark energy models, parametrized by multiple candidate equation of state, using the recently published Cosmic Microwave Background (CMB) temperature anisotropy data from Planck together with the WMAP-9 low-$\ell$ polarization data and data from low redshift su...
astro-ph_CO
Gravitational waves, dark energy and inflation: In this paper we first present a complete classification of gravitational waves according to their frequencies: (i) Ultra high frequency band (above 1 THz); (ii) Very high frequency band (100 kHz - 1 THz); (iii) High frequency band (10 Hz - 100 kHz); (iv) Middle frequency...
astro-ph_CO
Testing flatness of the universe with probes of cosmic distances and growth: When using distance measurements to probe spatial curvature, the geometric degeneracy between curvature and dark energy in the distance-redshift relation typically requires either making strong assumptions about the dark energy evolution or ...
astro-ph_CO
Effects of a Late Gravitational Transition on Gravitational Waves and Anticipated Constraints: We investigate the evolution of gravitational waves through discontinuous evolution (transition) of the Hubble expansion rate $H(z)$ at a sudden cosmological singularity, which may be due to a transition of the value of the...
astro-ph_CO
Cosmic string loop shapes: We analyze the shapes of cosmic string loops found in large-scale simulations of an expanding-universe string network. The simulation does not include gravitational back reaction, but we model that process by smoothing the loop using Lorentzian convolution. We find that loops at formation con...
astro-ph_CO
The sub-mJy radio population of the E-CDFS: optical and infrared counterpart identification: We study a sample of 883 sources detected in a deep Very Large Array survey at 1.4 GHz in the Extended Chandra Deep Field South. The paper focuses on the identification of their optical and infrared (IR) counterparts. We use ...
astro-ph_CO
Calibrated Ultra Fast Image Simulations for the Dark Energy Survey: Weak lensing by large-scale structure is a powerful technique to probe the dark components of the universe. To understand the measurement process of weak lensing and the associated systematic effects, image simulations are becoming increasingly importa...
astro-ph_CO
Metals and ionizing photons from dwarf galaxies: We estimate the potential contribution of M < 10^9 Msun dwarf galaxies to the reionization and early metal-enrichment of the Milky Way environment, or circum-Galactic Medium. Our approach is to use the observed properties of ancient stars (> 12 Gyr old) measured in nearb...
astro-ph_CO
The Evolution and Eddington Ratio Distribution of Compton Thick Active Galactic Nuclei: Previous studies of the active galactic nuclei (AGN) contribution to the cosmic X-ray background (CXB) consider only observable parameters such as luminosity and absorbing column. Here, for the first time, we extend the study of t...
astro-ph_CO
Environmental Effects on the Star Formation Activity in Galaxies at z=1.2 in the COSMOS Field: We investigate the relation between the star-formation activity in galaxies and environment at z=1.2 in the COSMOS field, using the fraction of [OII] emitters and the local galaxy density. The fraction of [OII] emitters app...
astro-ph_CO
Light Fields during Inflation from BOSS and Future Galaxy Surveys: Primordial non-Gaussianity generated by additional fields present during inflation offers a compelling observational target for galaxy surveys. These fields are of significant theoretical interest since they offer a window into particle physics in the i...
astro-ph_CO
Multiband Comparative Study of Optical Microvariability in RL vs. RQ Quasars: We present the results of an optical multi-band (BVR) photometric monitoring program of 22 core-dominated radio-loud quasars (CRLQs) and 22 radio-quiet quasars (RQQs). The aim was to compare the properties of microvariability in both types ...
astro-ph_CO
Connecting massive galaxies to dark matter halos in BOSS - I. Is galaxy color a stochastic process in high-mass halos?: We use subhalo abundance matching (SHAM) to model the stellar mass function (SMF) and clustering of the Baryon Oscillation Spectroscopic Survey (BOSS) "CMASS" sample at $z\sim0.5$. We introduce a no...
astro-ph_CO
X-ray observations of the merging cluster CIZA J2242.8+5301: Multiwavelength studies of radio relics at merger shocks set powerful constraints on the relics origin and formation mechanism. However, for X-ray observations, a main difficulty is represented by the low X-ray surface brightness far out in the cluster outski...
astro-ph_CO
Detectability of the cross-correlation between CMB lensing and stochastic GW background from compact object mergers: The anisotropies of the Stochastic Gravitational-Wave Background (SGWB) produced by merging compact binaries constitute a possible new probe of the Large-Scale Structure (LSS). However, the significant...
astro-ph_CO
A unique isolated dwarf spheroidal galaxy at D=1.9 Mpc: We present a photometric and spectroscopic study of the unique isolated nearby dSph galaxy KKR25. The galaxy was resolved into stars with HST/WFPC2 including old red giant branch and red clump. We have constructed a model of the resolved stellar populations and me...
astro-ph_CO
Cross-Correlation of Diffuse Synchrotron and Large-Scale Structures: We explore for the first time the method of cross-correlation of radio synchrotron emission and tracers of large-scale structure in order to detect the diffuse IGM/WHIM. We performed a cross-correlation of a 34 x 34 degree area of 2MASS galaxies for t...
astro-ph_CO
The Brightest of Reionizing Galaxies (BoRG) survey: Until now, investigating the early stages of galaxy formation has been primarily the realm of theoretical modeling and computer simulations, which require many physical ingredients and are challenging to test observationally. However, the latest Hubble Space Telescope...
astro-ph_CO
Episodic Star Formation Coupled to Reignition of Radio Activity in 3C 236: We present Hubble Space Telescope UV and optical imaging of the radio galaxy 3C 236, whose relic 4 Mpc radio jet lobes and inner 2 kpc CSS radio source are evidence of multiple epochs of AGN activity. Our data confirm the presence of four brig...
astro-ph_CO
Cosmological constraints from multiple tracers in spectroscopic surveys: We use the Fisher matrix formalism to study the expansion and growth history of the Universe using galaxy clustering with 2D angular cross-correlation tomography in spectroscopic or high resolution photometric redshift surveys. The radial informat...
astro-ph_CO
The early-type dwarf galaxy population of the Centaurus cluster: We present a photometric study of the early-type dwarf galaxy population of the Centaurus cluster, aiming at investigating the galaxy luminosity function (LF) and galaxy scaling relations down to the regime of galaxies with M_V~-10 mag. On deep VLT/FORS1 ...
astro-ph_CO
Sunyaev Zel'dovich effect in galaxy clusters cavities: thermal or non-thermal origin?: Several galaxy clusters host X-ray cavities, often filled with relativistic electrons emitting in the radio band. In the cluster MS 0735.6+7421 the cavities have been detected through the Sunyaev Zel'dovich (SZ) effect, but it has ...
astro-ph_CO
Calibrating Gamma-Ray Bursts by Using a Gaussian Process with Type Ia Supernovae: In this paper, we calibrate the Amati relation (the $E_{\rm p}$-${E}_{\rm iso}$ correlation) of gamma-ray bursts (GRBs) in a cosmology-independent way. By using Gaussian process to reconstruct the smoothed luminosity distance from the P...
astro-ph_CO
A Spectroscopic Model of the Type Ia Supernova--Host Galaxy Mass Correlation from SALT3: The unknown cause of the correlation between Type Ia supernova (SN Ia) Hubble residuals and their host-galaxy masses (the "mass step") may bias cosmological parameter measurements. To better understand the mass step, we develop a...
astro-ph_CO
The last breath of the young gigahertz-peaked spectrum radio source PKS 1518+047: We present the results from multi-frequency VLBA observations from 327 MHz to 8.4 GHz of the gigahertz-peaked spectrum radio source PKS 1518+047 (4C 04.51) aimed at studying the spectral index distribution across the source. Further mul...
astro-ph_CO
Caustic and hydrostatic mass bias: Implications for modified gravity: We propose and perform a joint analysis of the two different mass estimates of galaxy clusters, namely the hydrostatic and caustic techniques. Firstly, we show comprehensively that the mass bias between these two techniques can be possibly alleviated...
astro-ph_CO
Large-scale asymmetry in the distribution of galaxy spin directions -- analysis and reproduction: Recent independent observations using several different telescope systems an analysis methods have provided evidence of parity violation between the number of galaxies that spin in opposite directions. On the other hand,...
astro-ph_CO
An influence of the matter distribution on the positional accuracy of reference sources: We consider an influence of a non-stationary gravitational field of the Galaxy on the visible positions of extragalactic sources. A contribution of the baryonic component of the galactic matter as well as of the hidden matter (in...
astro-ph_CO
X-ray emission around the z=4.1 radio galaxy TNJ1338-1942 and the potential role of far-infrared photons in AGN Feedback: We report the discovery in an 80-ks observation of spatially-extended X-ray emission around the high-redshift radio galaxy TNJ1388-1942 (z=4.11) with the Chandra X-ray Observatory. The X-ray emiss...
astro-ph_CO
Deblending Galaxies with Generative Adversarial Networks: Deep generative models including generative adversarial networks (GANs) are powerful unsupervised tools in learning the distributions of data sets. Building a simple GAN architecture in PyTorch and training on the CANDELS data set, we generate galaxy images with...
astro-ph_CO
Stellar population and the origin of intra-cluster stars around brightest cluster galaxies: the case of NGC 3311: Context. We investigate the stellar population and the origin of diffuse light around brightest cluster galaxies. Aims. We study the stellar population of the dynamically hot stellar halo of NGC 3311, t...
astro-ph_CO
Big Bang Nucleosynthesis: As the early universe expands and cools the rates of the weak interactions that keep neutrinos in thermal equilibrium with the matter and the related rates of the reactions that inter-convert neutrons and protons decrease. Eventually, these rates fall below the expansion rate -- they freeze ou...
astro-ph_CO
First results on the search for dark matter in the Sun with the ANTARES neutrino telescope: The ANTARES collaboration is currently operating the largest neutrino detector in the Northern Hemisphere. One of the goals of ANTARES is the search for dark matter in the universe. In this paper, the first results on the sear...
astro-ph_CO
Detecting patchy reionization in the CMB: Upcoming cosmic microwave background (CMB) experiments will measure temperature fluctuations on small angular scales with unprecedented precision. Small-scale CMB fluctuations are a mixture of late-time effects: gravitational lensing, Doppler shifting of CMB photons by moving e...
astro-ph_CO
Viscosity, pressure, and support of the gas in simulations of merging cool-core clusters: Major mergers are considered to be a significant source of turbulence in clusters. We performed a numerical simulation of a major merger event using nested-grid initial conditions, adaptive mesh refinement, radiative cooling of ...
astro-ph_CO
Thermal SZ effect in a magnetized IGM dominated by interacting DM decay/annihilation during dark ages: During cosmic dawn, the thermal history of the universe is well studied, and a study of this era can give us some of the most useful insight into the universe before the recombination epoch. Its precise modeling and...
astro-ph_CO
Athena X-IFU synthetic observations of galaxy clusters to probe the chemical enrichment of the Universe: Answers to the metal production of the Universe can be found in galaxy clusters, notably within their Intra-Cluster Medium (ICM). The X-ray Integral Field Unit (X-IFU) on board the next-generation European X-ray o...
astro-ph_CO
The ~0.9 mJy sample: A mid-infrared spectroscopic catalog of 150 infrared-luminous, 24 micron selected galaxies at 0.3<z<3.5: We present a catalog of mid-infrared (MIR) spectra of 150 infrared (IR) luminous galaxies in the Spitzer extragalactic first look survey obtained with IRS on board Spitzer. The sample is selec...
astro-ph_CO
Probing general relativistic effects during AGN X-ray eclipses: Long X-ray observations of bright Active Galactic Nuclei show that X-ray eclipses, with durations from a few hours to a few days, are rather common. This opens up a new window of opportunity in the search for signatures of relativistic effects in AGNs: an ...
astro-ph_CO
The Effects of Calibration on the Bias of Shear Measurements: Forthcoming large-scale surveys will soon attempt to measure cosmic shear to an unprecedented level of accuracy, requiring a similarly high level of accuracy in the shear measurements of galaxies. Factors such as pixelisation, imperfect point-spread function...
astro-ph_CO
Post-reionization HI 21-cm signal: A probe of negative cosmological constant: In this study, we investigate a cosmological model involving a negative cosmological constant (AdS vacua in the dark energy sector). We consider a quintessence field on top of a negative cosmological constant and study its impact on cosmolo...
astro-ph_CO
Lyalpha versus X-ray heating in the high-z IGM: In this paper we examine the effect of X-ray and Lyalpha photons on the intergalactic medium temperature. We calculate the photon production from a population of stars and micro-quasars in a set of cosmological hydrodynamic simulations which self-consistently follow the d...
astro-ph_CO
Unsupervised Searches for Cosmological Parity-Violation: An Investigation with Convolutional Neural Networks: Recent measurements of the $4$-point correlation functions (4PCF) from spectroscopic surveys provide evidence for parity-violations in the large-scale structure of the Universe. If physical in origin, this co...
astro-ph_CO
Lower Bounds on Intergalactic Magnetic Fields from Simultaneously Observed GeV-TeV Light Curves of the Blazar Mrk 501: We derive lower bounds on intergalactic magnetic fields (IGMFs) from upper limits on the pair echo emission from the blazar Mrk 501, that is, delayed GeV emission from secondary $e^{-}e^{+}$ pairs pr...
astro-ph_CO
The Case Against Warm or Self-Interacting Dark Matter as Explanations for Cores in Low Surface Brightness Galaxies: Warm dark matter (WDM) and self-interacting dark matter (SIDM) are often motivated by the inferred cores in the dark matter halos of low surface brightness (LSB) galaxies. We test thermal WDM, non-therm...
astro-ph_CO
Astrophysical information from the Rayleigh-Jeans Tail of the CMB: One of the explanations for the recent EDGES-LOW band 21-cm measurements of a strong absorption signal around 80~MHz is the presence of an excess radio background to the Cosmic Microwave Background (CMB). Such excess can be produced by the decay of unst...
astro-ph_CO
Inflation in a closed universe: To derive a power spectrum for energy density inhomogeneities in a closed universe, we study a spatially-closed inflation-modified hot big bang model whose evolutionary history is divided into three epochs: an early slowly-rolling scalar field inflation epoch and the usual radiation and ...
astro-ph_CO
On the nature of sodium excess objects. I. Data and observed trends: Several studies have reported the presence of sodium excess objects that have neutral atomic absorption lines at 5895A (NaD) and 8190A that are deeper than expected based on stellar population models. van Dokkum & Conroy proposed that low-mass stars a...
astro-ph_CO
The VLA-COSMOS Perspective on the IR-Radio Relation. I. New Constraints on Selection Biases and the Non-Evolution of the IR/Radio Properties of Star Forming and AGN Galaxies at Intermediate and High Redshift: VLA 1.4 GHz (rms noise ~0.012 mJy) and MIPS 24 and 70 micron (rms noise ~0.02 and ~1.7 mJy, respectively) o...
astro-ph_CO
Conserved Quantities in Lemaitre-Tolman-Bondi Cosmology: We study linear perturbations to a Lema{\^\i}tre-Tolman-Bondi (LTB) background spacetime. Studying the transformation behaviour of the perturbations under gauge transformations, we construct gauge invariant quantities. We show, using the perturbed energy conserva...
astro-ph_CO
How to Falsify the GR+LambdaCDM Model with Galaxy Redshift Surveys: A wide range of models describing modifications to General Relativity have been proposed, but no fundamental parameter set exists to describe them. Similarly, no fundamental theory exists for dark energy to parameterize its potential deviation from a c...
astro-ph_CO
Gravitational Waves in Cold Dark Matter: We study the effects of cold dark matter on the propagation of gravitational waves of astrophysical and primordial origin. We show that the dominant effect of cold dark matter on gravitational waves from astrophysical sources is a small frequency dependent modification of the pr...
astro-ph_CO
The effects of non-linearity on the growth rate constraint from velocity correlation functions: The two-point statistics of the cosmic velocity field, measured from galaxy peculiar velocity (PV) surveys, can be used as a dynamical probe to constrain the growth rate of large-scale structures in the universe. Most work...
astro-ph_CO
A SINFONI Integral Field Spectroscopy Survey for Galaxy Counterparts to Damped Lyman-alpha Systems - V. Neutral and Ionised Phase Metallicities: The gas-phase and stellar metallicities have proven to be important parameters to constrain the star formation history of galaxies. However, HII regions associated with rece...
astro-ph_CO
Big Bang Nucleosynthesis with an Inhomogeneous Primordial Magnetic Field Strength: We investigate the effect on the Big Bang Nucleosynthesis (BBN) from the presence of a stochastic primordial magnetic field (PMF) whose strength is spatially inhomogeneous. We assume a uniform total energy density and a gaussian distri...
astro-ph_CO