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Interferences in the Stochastic Gravitational Wave Background: Although the expansion of the Universe explicitly breaks the time-translation symmetry, cosmological predictions for the stochastic gravitational wave background (SGWB) are usually derived under the so-called stationary hypothesis. By dropping this assumpti...
astro-ph_CO
Diffuse Radio Emission in Abell 754: We present a low frequency study of the diffuse radio emission in the galaxy cluster A754. We present new 150 MHz image of the galaxy cluster A754 made with the Giant Metrewave Radio Telescope (GMRT) and discuss the detection of 4 diffuse features. We compare the 150 MHz image with ...
astro-ph_CO
The slope of the Baryonic Tully-Fisher relation: We present the results of a baryonic Tully-Fisher relation (BTFR) study for a local sample of relatively isolated disk galaxies. We derive a BTFR with a slope near 3 measured over about 4 dex in baryon mass for our combined \textrm{H\,\scriptsize{I}} and bright spiral di...
astro-ph_CO
The CMB Dipole: Eppur Si Muove: The largest temperature anisotropy in the cosmic microwave background (CMB) is the dipole. The simplest interpretation of the dipole is that it is due to our motion with respect to the rest frame of the CMB. As well as creating the $\ell$=1 mode of the CMB sky, this motion affects all as...
astro-ph_CO
Large non-Gaussian Halo Bias from Single Field Inflation: We calculate Large Scale Structure observables for non-Gaussianity arising from non-Bunch-Davies initial states in single field inflation. These scenarios can have substantial primordial non-Gaussianity from squeezed (but observable) momentum configurations. The...
astro-ph_CO
Improving lensing cluster mass estimate with flexion: Gravitational lensing has long been considered as a valuable tool to determine the total mass of galaxy clusters. The shear profile as inferred from the statistics of ellipticity of background galaxies allows to probe the cluster intermediate and outer regions thus ...
astro-ph_CO
Possible Alternate Scenario for short Duration GRBs: In this paper we look at new class of objects made up entirely of dark matter particles. We look at these objects as possible candidate for short duration gamma ray bursts eliminating the baryon load problem. These could also provide a possible scenario for the forma...
astro-ph_CO
Constraints on Primordial Magnetic Fields from Planck combined with the South Pole Telescope CMB B-mode polarization measurements: A primordial magnetic field (PMF) present before recombination can leave specific signatures on the cosmic microwave background (CMB) fluctuations. Of particular importance is its contrib...
astro-ph_CO
Testing consistency of general relativity with kinematic and dynamical probes: In this work, we test consistency relations between a kinematic probe, the observational Hubble data, and a dynamical probe, the growth rates for cosmic large scale structure, which should hold if general relativity is the correct theory o...
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Testing General Relativity using the Environmental Dependence of Dark Matter Halos: In this Letter, we investigate the environmental dependence of dark matter halos in theories that attempt to explain the accelerated expansion of the Universe by modifying general relativity (GR). Using high-resolution N-body simulati...
astro-ph_CO
The Formation of the Local Group Planes of Galaxies: The confinement of most satellite galaxies in the Local Group to thin planes presents a challenge to the theory of hierarchical galaxy clustering. The PAndAS collaboration has identified a particularly thin configuration with kinematic coherence among companions of M...
astro-ph_CO
Taxonomy of Dark Energy Models: The accelerated expansion of the Universe is one of the main discoveries of the past decades, indicating the presence of an unknown component: the dark energy. Evidence of its presence is being gathered by a succession of observational experiments with increasing precision in its measure...
astro-ph_CO
Reconstructing the Initial Density Field of the Local Universe: Method and Test with Mock Catalogs: Our research objective in this paper is to reconstruct an initial linear density field, which follows the multivariate Gaussian distribution with variances given by the linear power spectrum of the current CDM model an...
astro-ph_CO
Anisotropic Galactic Outflows and Enrichment of the Intergalactic Medium. II. Numerical Simulations: We combine an analytic model for anisotropic outflows and galaxy formation with numerical simulations of large-scale structure and halo formation to study the impact of galactic outflows on the evolution of the IGM. W...
astro-ph_CO
Gravitational energy as dark energy: Average observational quantities: In the timescape scenario cosmic acceleration is understand as an apparent effect, due to gravitational energy gradients that grow when spatial curvature gradients become significant with the nonlinear growth of cosmic structure. This affects the ca...
astro-ph_CO
Production of EMRIs in Supermassive Black Hole Binaries: We consider the formation of extreme mass-ratio inspirals (EMRIs) sourced from a stellar cusp centred on a primary supermassive black hole (SMBH) and perturbed by an inspiraling less massive secondary SMBH. The problem is approached numerically, assuming the star...
astro-ph_CO
The SLUGGS Survey: Globular cluster system kinematics and substructure in NGC 4365: We present a kinematic analysis of the globular cluster (GC) system of the giant elliptical galaxy NGC 4365 and find several distinct kinematic substructures. This analysis is carried out using radial velocities for 269 GCs, obtained ...
astro-ph_CO
A new probe of the small-scale primordial power spectrum: astrometric microlensing by ultracompact minihalos: The dark matter enclosed in a density perturbation with a large initial amplitude (delta-rho/rho > 1e-3) collapses shortly after recombination and forms an ultracompact minihalo (UCMH). Their high central den...
astro-ph_CO
Discovery of a supercluster in the ZOA in Vela: We report the discovery of a potentially major supercluster that extends across the Galactic Plane in the constellation of Vela, at a mean recessional velocity of ~18,000 km/s. Recent multi-object spectroscopic observations of this Vela Supercluster (VSCL), using AAOmega+...
astro-ph_CO
Modified Starobinsky Inflation: Starobinsky has suggested an inflation model which is obtained from the vacuum Einstein's equations modified by the one-loop corrections due to quantized matter fields. Although the one-loop gravitational action is not known for a general FRW background, it can be obtained in a de Sitter...
astro-ph_CO
The eROSITA Final Equatorial-Depth Survey (eFEDS): LOFAR view of brightest cluster galaxies and AGN feedback: During the performance verification phase of the SRG/eROSITA telescope, the eROSITA Final Equatorial-Depth Survey (eFEDS) has been carried out. It covers a 140 deg$^2$ field located at 126$^\circ <$ R.A. $< 1...
astro-ph_CO
Exploring suppressed long-distance correlations as the cause of suppressed large-angle correlations: The absence of large-angle correlations in the map of cosmic microwave background temperature fluctuations is among the well-established anomalies identified in full-sky and cut-sky maps over the past three decades. S...
astro-ph_CO
Reconstructing the interaction between dark energy and dark matter using Gaussian Processes: We present a nonparametric approach to reconstruct the interaction between dark energy and dark matter directly from SNIa Union 2.1 data using Gaussian processes, which is a fully Bayesian approach for smoothing data. In this...
astro-ph_CO
Reconstructing the baryon acoustic oscillations using biased tracers: The reconstruction of the initial conditions of the Universe is an important topic in cosmology, particularly in the context of sharpening the measurement of the baryon acoustic oscillation (BAO) peak. Nonlinear reconstruction algorithms developed in...
astro-ph_CO
Symmetry of the CMB sky as a new test of its statistical isotropy. Non Cosmological Octupole?: In this article we propose a novel test for statistical anisotropy of the CMB. The test is based on the fact, that the Galactic foregrounds have a remarcably strong symmetry with respect to their antipodal points and with r...
astro-ph_CO
Discriminating power of milli-lensing observations for dark matter models: The nature of dark matter (DM) is still under intense debate. Sub-galactic scales are particularly critical, as different, currently viable DM models make diverse predictions on the expected abundance and density profile of DM haloes on these ...
astro-ph_CO
Steep Faint-end Slopes of Galaxy Mass and Luminosity Functions at z>=6 and the Implications for Reionisation: We present the results of a numerical study comparing photometric and physical properties of simulated z=6-9 galaxies to the observations taken by the WFC3 instrument aboard the Hubble Space Telescope. Using ...
astro-ph_CO
Herschel-ATLAS: far-infrared properties of radio-selected galaxies: We use the Herschel-ATLAS science demonstration data to investigate the star-formation properties of radio-selected galaxies in the GAMA-9h field as a function of radio luminosity and redshift. Radio selection at the lowest radio luminosities, as expec...
astro-ph_CO
Beyond the Boost: Measuring the intrinsic dipole of the CMB using the spectral distortions of the monopole and quadrupole: We present a general framework for accurate spectral modeling of the low multipoles of the cosmic microwave background (CMB) as observed in a boosted frame. In particular, we demonstrate how spec...
astro-ph_CO
Using Cumulative Number Densities to Compare Galaxies across Cosmic Time: Comparing galaxies across redshifts at fixed cumulative number density is a popular way to estimate the evolution of specific galaxy populations. This method ignores scatter in mass accretion histories and galaxy-galaxy mergers, which can lead to...
astro-ph_CO
Constraints on primordial magnetic fields from the optical depth of the cosmic microwave background: Damping of magnetic fields via ambipolar diffusion and decay of magnetohydrodynamical (MHD) turbulence in the post decoupling era heats the intergalactic medium (IGM). Delayed recombination of hydrogen atoms in the IG...
astro-ph_CO
The cosmic shallows I: interaction of CMB photons in extended galaxy halos: We report and analyse the presence of foregrounds in the cosmic microwave background (CMB) radiation associated to extended galactic halos. Using the cross correlation of Planck and WMAP maps and the 2MRS galaxy catalogue, we find that the me...
astro-ph_CO
The observed galaxy bispectrum from single-field inflation in the squeezed limit: Using the consistency relation in Fourier space, we derive the observed galaxy bispectrum from single-field inflation in the squeezed limit, in which one of the three modes has a wavelength much longer than the other two. This provides ...
astro-ph_CO
The environment and redshift dependence of accretion onto dark matter halos and subhalos: A dark-matter-only Horizon Project simulation is used to investigate the environment- and redshift- dependence of accretion onto both halos and subhalos. These objects grow in the simulation via mergers and via accretion of diff...
astro-ph_CO
Performance of Non-Parametric Reconstruction Techniques in the Late-Time Universe: In the context of a Hubble tension problem that is growing in its statistical significance, we reconsider the effectiveness of non-parametric reconstruction techniques which are independent of prescriptive cosmological models. By takin...
astro-ph_CO
Extracting the Global 21-cm signal from Cosmic Dawn and Epoch of Reionization in the presence of Foreground and Ionosphere: Detection of redshifted \ion{H}{i} 21-cm emission is a potential probe for investigating the Universe's first billion years. However, given the significantly brighter foreground, detecting 21-cm...
astro-ph_CO
ALMA Observations of SPT-Discovered, Strongly Lensed, Dusty, Star-Forming Galaxies: We present Atacama Large Millimeter/submillimeter Array (ALMA) 860 micrometer imaging of four high-redshift (z=2.8-5.7) dusty sources that were detected using the South Pole Telescope (SPT) at 1.4 mm and are not seen in existing radio...
astro-ph_CO
Primordial Non-Gaussianity in the Cosmic Microwave Background: In the last few decades, advances in observational cosmology have given us a standard model of cosmology. We know the content of the universe to within a few percent. With more ambitious experiments on the way, we hope to move beyond the knowledge of what t...
astro-ph_CO
Loop contributions to the scalar power spectrum due to quartic order action in ultra slow roll inflation: [Abridged] In contemporary literature, the calculation of modifications to the inflationary scalar power spectrum due to the loops from the higher order interaction terms in the Hamiltonian have led to a discussi...
astro-ph_CO
Explaining Excess Dipole in NVSS Data Using Superhorizon Perturbation: Many observations in recent times have shown evidence against the standard assumption of isotropy in the Big Bang model. Introducing a superhorizon scalar metric perturbation has been able to explain some of these anomalies. In this work, we probe t...
astro-ph_CO
Cosmological backreaction: This work summarises some of the attempts to explain the phenomenon of dark energy as an effective description of complex gravitational physics and the proper interpretation of observations. Cosmological backreaction has been shown to be relevant for observational (precision) cosmology, never...
astro-ph_CO
Unleashing Positive Feedback: Linking the Rates of Star Formation, Supermassive Black Hole Accretion and Outflows in Distant Galaxies: Pressure-regulated star formation is a simple variant on the usual supernova-regulated star formation efficiency that controls the global star formation rate as a function of cold gas...
astro-ph_CO
Flaring Patterns in Blazars: Blazars radiate from relativistic jets launched by a supermassive black hole along our line of sight; the subclass of FSRQs exhibits broad emission lines, a telltale sign of a gas-rich environment and high accretion rate, contrary to the other subclass of the BL Lacertae objects. We show th...
astro-ph_CO
The origin of the WMAP quadrupole: The cosmic microwave background (CMB) temperature maps from the Wilkinson Microwave Anisotropy Probe (WMAP) are of great importance for cosmology. In previous work we had developed a pipeline for map-making independently of the WMAP team. The new maps produced from the WMAP raw data b...
astro-ph_CO
Density Perturbation Growth in Teleparallel Cosmology: We study the cosmological perturbations in teleparallel dark energy models in which there is a dynamical scalar field with a non-minimal coupling to gravity. We find that the propagating degrees of freedom are the same as in quintessence cosmology despite that vari...
astro-ph_CO
Testing the Alignment Tendency of Some Polarized Radio Sources: Measuring the alignment of polarized radio sources requires comparing vectors at different locations on the sky, i.e. on a sphere. A test of alignment is derived herein. While both large scale and coordinate independent, the test avoids the mathematical su...
astro-ph_CO
Non-Gaussianity of diffuse Galactic synchrotron emission at 408 MHz: Diffuse Galactic emission at low frequencies is a major contaminant for studies of redshifted $21$ cm line studies. Removal of these foregrounds is essential for exploiting the signal from neutral hydrogen at high redshifts. Analysis of foregrounds an...
astro-ph_CO
Spherical collapse model with non-clustering dark energy: We investigate a spherical overdensity model for the non-clustering dark energy (DE) with the constant equation of state, w in a flat universe. In this case, the exact solution for the evolution of the scale factor is obtained for general w. We also obtain the e...
astro-ph_CO
The Size, Shape and Orientation of Cosmological Voids in the Sloan Digital Sky Survey: We present a detailed description of our void finding algorithm which is an extension of the prescription by Hoyle and Vogeley (2002). We include a discussion of the reproducibility and robustness of the algorithm as well as the st...
astro-ph_CO
The Origin of Dust in Early-Type Galaxies and Implications for Accretion onto Supermassive Black Holes: We have conducted an archival Spitzer study of 38 early-type galaxies (ETGs) in order to determine the origin of the dust in approximately half of this population. Our sample galaxies generally have good wavelength...
astro-ph_CO
Accounting for selection effects in the BH-bulge relations: No evidence for cosmological evolution: The redshift evolution of the black hole - bulge relations is an essential observational constraint for models of black hole - galaxy coevolution. In addition to the observational challenges for these studies, conclusi...
astro-ph_CO
Enhancing Bispectrum Estimators for Galaxy Redshift Surveys with Velocities: We forecast the ability of bispectrum estimators to constrain primordial non-Gaussianity using future photometric galaxy redshift surveys. A full-sky survey with photometric redshift resolution of $\sigma_z/(1+z)=0.05$ in the redshift range ...
astro-ph_CO
Dark matter decay in the Milky Way halo: Dark matter may be detected in X-ray decay, including from the decay of the dark matter particles that make up the Milky Way (MW) halo. We use a range of density profiles to compute X-ray line intensity profiles, with a focus on the resonantly produced sterile neutrino dark matt...
astro-ph_CO
Constraints on primordial black holes with CMB spectral distortions: In the mixed dark matter scenarios consisting of primordial black holes (PBHs) and weakly interacting massive particles (WIMPs), WIMPs can be accreted onto PBHs to form ultracompact minihalos (UCMHs) with a density spike in the early universe. Compare...
astro-ph_CO
New polarimetric constraints on axion-like particles: We show that the parameter space of axion-like particles can be severly constrained using high-precision measurements of quasar polarisations. Robust limits are derived from the measured bounds on optical circular polarisation and from the distribution of linear pol...
astro-ph_CO
Are "Changing-Look'' Active Galactic Nuclei Special in the Coevolution of Supermassive Black Holes and their Hosts? I: The nature of the so-called ``changing-look'' (CL) active galactic nucleus (AGN), which is characterized by spectral-type transitions within $\sim10$~yr, remains an open question. As the first in our...
astro-ph_CO
Spectrum of the Anomalous Microwave Emission in the North Celestial Pole with WMAP 7-Year data: We estimate the frequency spectrum of the diffuse anomalous microwave emission (AME) on the North Celestial Pole (NCP) region of the sky with the Correlated Component Analysis (CCA) component separation method applied to W...
astro-ph_CO
The modified gravity lightcone simulation project I: Statistics of matter and halo distributions: We introduce a set of four very high resolution cosmological simulations for exploring $f(R)$-gravity, with $2048^3$ particles in $768\,h^{-1}\textrm{Mpc}$ and $1536\,h^{-1}\textrm{Mpc}$ simulation boxes, both for a $|\o...
astro-ph_CO
Simultaneous modelling of matter power spectrum and bispectrum in the presence of baryons: We demonstrate that baryonification algorithms, which displace particles in gravity-only simulations according to physically-motivated prescriptions, can simultaneously capture the impact of baryonic physics on the 2 and 3-poin...
astro-ph_CO
The role of quasars in galaxy formation: We discuss evidence that quasars, and more generally radio jets, may have played an active role in the formation stage of galaxies by inducing star formation, i.e. through positive feedback. This mechanism first proposed in the 70's has been considered as anecdotic until now, co...
astro-ph_CO
A Hydrodynamical Approach to CMB mu-distortions: Spectral distortion of the cosmic microwave background provides a unique opportunity to probe primordial perturbations on very small scales by performing large-scale measurements. We discuss in a systematic and pedagogic way all the relevant physical phenomena involved i...
astro-ph_CO
Extending the Coyote emulator to dark energy models with standard $w_0$-$w_a$ parametrization of the equation of state: We discuss an extension of the Coyote emulator to predict non-linear matter power spectra of dark energy (DE) models with a scale factor dependent equation of state of the form w = w_0 + ( 1 - a )w_...
astro-ph_CO
Corrective effect of many-body interactions in dynamical friction: Dynamical friction is a fundamental and important phenomenon in astrophysics. The Chandrasekhar formula is a well-known analytical estimation of the effect. However, current astrophysicists have realized that the formula is not correct in some cases bec...
astro-ph_CO
Non-linear Matter Spectra in Coupled Quintessence: We consider cosmologies in which a dark-energy scalar field interacts with cold dark matter. The growth of perturbations is followed beyond the linear level by means of the time-renormalization-group method, which is extended to describe a multi-component matter sector...
astro-ph_CO
The H0 trouble: Confronting Non-thermal Dark Matter and Phantom Cosmology with the CMB, BAO, and Type Ia Supernovae data: We have witnessed different values of the Hubble constant being found in the literature in the past years. Albeit, early measurements often result in an $H_0$ much smaller than those from late-tim...
astro-ph_CO
Nonstandard cosmology: Considering radial geodesics in the Robertson-Walker metric leads us to abandon the co-moving coordinates. Instead we work in the cosmic rest frame. Since then the matter is in motion, the solution of Einstein's equations is more complicated. We calculate the first correction to standard cosmolog...
astro-ph_CO
An ALMA survey of submillimetre galaxies in the Extended Chandra Deep Field South: High resolution 870um source counts: We report the first counts of faint submillimetre galaxies (SMG) in the 870-um band derived from arcsecond resolution observations with the Atacama Large Millimeter Array (ALMA). We have used ALMA t...
astro-ph_CO
Dynamic of the accelerated expansion of the universe in the DGP model: According to experimental data of SNe Ia (Supernovae type Ia), we will discuss in detial dynamics of the DGP model and introduce a simple parametrization of matter $\omega$, in order to analyze scenarios of the expanding universe and the evolution o...
astro-ph_CO
Numerical evaluation of inflationary 3-point functions on curved field space: We extend the public CppTransport code to calculate the statistical properties of fluctuations in multiple-field inflationary models with curved field space. Our implementation accounts for all physical effects at tree-level in the 'in-in' ...
astro-ph_CO
Exploratory X-ray Monitoring of Luminous Radio-Quiet Quasars at High Redshift: Initial Results: We present initial results from an exploratory X-ray monitoring project of two groups of comparably luminous radio-quiet quasars (RQQs). The first consists of four sources at 4.10 <= z <= 4.35, monitored by Chandra, and th...
astro-ph_CO
Primordial magnetic field generation via primordial black hole disks: Large scale primordial magnetic fields (PMFs) threading the intergalactic medium are observed ubiquitously in the Universe playing a key role in the cosmic evolution. Their origin is still debated constituting a very active field of research. In the ...
astro-ph_CO
Apparent Superluminality of Lensed Gravitational Waves: We consider gravitational wave (GW) sources with an associated electromagnetic (EM) counterpart, and analyze the time delay between both signals in the presence of lensing. If GWs have wavelengths comparable to the Schwarzschild radius of astrophysical lenses, the...
astro-ph_CO
Convolution Lagrangian perturbation theory for biased tracers beyond general relativity: We compare analytic predictions for real and Fourier space two-point statistics for biased tracers from a variety of Lagrangian Perturbation Theory approaches against those from state of the art N-body simulations in $f(R)$ Hu-Sa...
astro-ph_CO
Test of cosmic isotropy in the Planck era: The two fundamental assumptions in cosmology are that the Universe is statistically homogeneous and isotropic when averaged on large scales. Given the big implication of these assumptions, there has been a lot of statistical tests carried out to verify their validity. Since th...
astro-ph_CO
Composition of Low Redshift Halo Gas: Halo gas in low-z (z<0.5) >0.1L* galaxies in high-resolution, large-scale cosmological hydrodynamic simulations is examined with respect to three components: (cold, warm, hot) with temperatures equal to (<10^5, 10^{5-6}, >10^6)K, respectively. The warm component is compared, utiliz...
astro-ph_CO
Describing variations of the Fisher-matrix across parameter space: Forecasts in cosmology, both with Monte-Carlo Markov-chain methods and with the Fisher matrix formalism, depend on the choice of the fiducial model because both the signal strength of any observable as well as the model nonlinearities linking observable...
astro-ph_CO
The effects of baryon physics, black holes and AGN feedback on the mass distribution in clusters of galaxies: The spatial distribution of matter in clusters of galaxies is mainly determined by the dominant dark matter component, however, physical processes involving baryonic matter are able to modify it significantly...
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Distribution function approach to redshift space distortions. Part IV: perturbation theory applied to dark matter: We develop a perturbative approach to redshift space distortions (RSD) using the phase space distribution function approach and apply it to the dark matter redshift space power spectrum and its moments. ...
astro-ph_CO
Interplanetary Dust as a Foreground for the LiteBIRD CMB Satellite Mission: As ever-more sensitive experiments are made in the quest for primordial CMB B Modes, the number of potentially significant astrophysical contaminants becomes larger as well. Thermal emission from interplanetary dust, for example, has been det...
astro-ph_CO
Cospatial 21 cm and metal-line absorbers in the epoch of reionization -- I : Incidence and observability: Overdense, metal-rich regions, shielded from stellar radiation might remain neutral throughout reionization and produce metal as well as 21 cm absorption lines. Simultaneous absorption from metals and 21 cm can c...
astro-ph_CO
The Majority of Compact Massive Galaxies at z~2 are Disk Dominated: We investigate the stellar structure of massive, quiescent galaxies at z~2, based on Hubble Space Telescope/WFC3 imaging from the Early Release Science program. Our sample of 14 galaxies has stellar masses of M* > 10^{10.8} Msol and photometric redshif...
astro-ph_CO
Constraining Quasar and IGM Properties Through Bubble Detection in Redshifted 21-cm Maps: The infrared detection of a z>7 quasar has opened up a new window to directly probe the IGM during the epoch of reionization. In this paper we theoretically consider the possibility of detecting the ionized bubble around a z=8 q...
astro-ph_CO
Empirical predictions for (sub-)millimeter line and continuum deep fields: [abridged] Modern (sub-)millimeter/radio interferometers will enable us to measure the dust and molecular gas emission from galaxies that have luminosities lower than the Milky Way, out to high redshifts and with unprecedented spatial resoluti...
astro-ph_CO
Photometric Calibrations for 21st Century Science: The answers to fundamental science questions in astrophysics, ranging from the history of the expansion of the universe to the sizes of nearby stars, hinge on our ability to make precise measurements of diverse astronomical objects. As our knowledge of the underlying p...
astro-ph_CO
The optical spectra of X-shaped radio galaxies: X-shaped radio galaxies are defined by their peculiar large-scale radio morphology. In addition to the classical double-lobed structure they have a pair of low-luminosity wings that straddles the nucleus at almost right angles to the active lobes, thus giving the impressi...
astro-ph_CO
Constraints on Cosmographic Functions of Cosmic Chronometers Data Using Gaussian Processes: We study observational constraints on the cosmographic functions up to the fourth derivative of the scale factor with respect to cosmic time, i.e., the so-called snap function, using the non-parametric method of Gaussian Proce...
astro-ph_CO
Designing Horndeski and the effective fluid approach: We present a family of designer Horndeski models, i.e. models that have a background exactly equal to that of the $\Lambda$CDM model but perturbations given by the Horndeski theory. Then, we extend the effective fluid approach to Horndeski theories, providing simple...
astro-ph_CO
Ghostly Galaxies as Solitons of Bose-Einstein Dark Matter: The large dark cores of common dwarf galaxies are unexplained by the standard heavy particle interpretation of dark matter. This puzzle is exacerbated by the discovery of a very large but barely visible, dark matter dominated galaxy Antlia II orbiting the Mil...
astro-ph_CO
Neutrino signals from Neutron Star implosions to Black Holes: We calculate the neutrino luminosity in an astrophysical scenario where dark matter is captured by a neutron star which eventually implodes to form a low mass black hole. The Trojan horse scenario involves the collapse of a neutron star (NS) due to the accum...
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Effect of halo bias and Lyman Limit Systems on the history of cosmic reionization: We extend the existing analytical model of reionization by Furlanetto et al. (2004) to include the biasing of reionization sources and additional absorption by Lyman Limit systems. Our model is, by construction, consistent with the obs...
astro-ph_CO
The WiggleZ Dark Energy Survey: measuring the cosmic expansion history using the Alcock-Paczynski test and distant supernovae: Astronomical observations suggest that today's Universe is dominated by a dark energy of unknown physical origin. One of the most notable consequences in many models is that dark energy shoul...
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UV-to-FIR analysis of Spitzer/IRAC sources in the Extended Groth Strip II: Photometric redshifts, Stellar masses and Star formation rates: Based on the ultraviolet to far-infrared photometry already compiled and presented in a companion paper (Barro et al. 2011a, Paper I), we present a detailed SED analysis of nearly...
astro-ph_CO
Oxford SWIFT IFS and multi-wavelength observations of the Eagle galaxy at z=0.77: The `Eagle' galaxy at a redshift of 0.77 is studied with the Oxford Short Wavelength Integral Field Spectrograph (SWIFT) and multi-wavelength data from the All-wavelength Extended Groth strip International Survey (AEGIS). It was chosen ...
astro-ph_CO
Stellar population gradients in the cores of nearby field E+A galaxies: We have selected a sample of local E+A galaxies from the Sloan Digital Sky Survey (SDSS) Data Release 7 for follow up integral field spectroscopy with the Wide Field Spectrograph (WiFeS) on the ANU 2.3-m telescope. The sample was selected using the...
astro-ph_CO
There is No Missing Satellites Problem: A critical challenge to the cold dark matter (CDM) paradigm is that there are fewer satellites observed around the Milky Way than found in simulations of dark matter substructure. We show that there is a match between the observed satellite counts corrected by the detection effic...
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Cosmology before noon with multiple galaxy populations: Near-future facilities observing the high-redshift universe ($2<z<5$) will have an opportunity to take advantage of "multi-tracer" cosmology by observing multiple tracers of the matter density field: Lyman alpha emitters (LAE), Lyman break galaxies (LBG), and CMB ...
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Interpreting the Clustering of Distant Red Galaxies: We analyze the angular clustering of z~2.3 distant red galaxies (DRGs) measured by Quadri et al 2008. We find that, with robust estimates of the measurement errors and realistic halo occupation distribution modeling, the measured clustering can be well fit within sta...
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Where stars form and live at high redshift: clues from the infrared: The relation between dark matter halos and the loci of star formation at high redshift is a pressing question in contemporary cosmology. Matching the abundance of halos to the abundance of infrared (IR) galaxies, we explicit the link between dark matt...
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Cyclic Cosmology from the Little Rip: We revisit a cyclic cosmology scenario proposed in 2007 to examine whether its hypotheses can be sustained if the underlying big rip evolution, which was assumed there, is replaced by the recently proposed little rip. We show that the separation into causal patches at turnaround is...
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Redshift drift in varying speed of light cosmology: We derive a redshift drift formula within the framework of varying speed of light (VSL) theory using the specific ansatz for the variability of $c(t) = c_0 a^n(t)$. We show that negative values of the parameter $n$, which correspond to diminishing value of the speed o...
astro-ph_CO