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Gravitational lensing effects of supermassive black holes in cluster environments: This study explores the gravitational lensing effects of supermassive black holes (SMBHs) in galaxy clusters. While the presence of central SMBHs in galaxies is firmly established, recent work from high-resolution simulations predict t...
Anisotropic Distance Ladder in Pantheon+ Supernovae: We decompose Pantheon+ Type Ia supernovae (SN) in hemispheres on the sky finding angular variations up to $4$ km/s/Mpc in the Hubble constant $H_0$ both in the SH0ES redshift range $0.0233 < z < 0.15$ and in extended redshift ranges. The variations are driven largely...
The dusty heart of nearby active galaxies -- II. From clumpy torus models to physical properties of dust around AGN: The dusty environments (= "dust tori'') of AGN are now in reach of observations. Following our paper I on ground-based mid-IR spectro-photometry (H\"onig et al. 2010), we present an upgrade to our radi...
Baryon Acoustic Oscillations in the Sloan Digital Sky Survey Data Release 7 Galaxy Sample: The spectroscopic Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) galaxy sample represents the final set of galaxies observed using the original SDSS target selection criteria. We analyse the clustering of galaxies within ...
GOODS-Herschel: radio-excess signature of hidden AGN activity in distant star-forming galaxies: We present here a new spectral energy distribution (SED) fitting approach that we adopt to select radio-excess sources amongst distant star-forming galaxies in the GOODS-Herschel (North) field and to reveal the presence of...
Integral Field Spectroscopy surveys of nearby spiral and U-LIRG galaxies: We describe the observations and preliminary results of the gas-phase analysis based on two ongoing, wide-field Integral Field Spectroscopy (IFS) surveys: the PPAK IFS Nearby Galaxies Survey (PINGS), targeting disc galaxies; and the VIMOS-IFU obs...
Single parameter galaxy classification: The Principal Curve through the multi-dimensional space of galaxy properties: We propose to describe the variety of galaxies from SDSS by using only one affine parameter. To this aim, we build the Principal Curve (P-curve) passing through the spine of the data point cloud, cons...
Toward Cosmological Standard Timers in Primordial Black Hole Binaries: We propose that primordial black hole (PBH) binary systems can lead to standard timers in tracking the evolution of the Universe. Through gravitational waves from monochromatic PBH binaries, the probability distribution on major axis and eccentricit...
The reach of next-to-leading-order perturbation theory for the matter bispectrum: We provide a comparison between the matter bispectrum derived with different flavours of perturbation theory at next-to-leading order and measurements from an unprecedentedly large suite of $N$-body simulations. We use the $\chi^2$ good...
Modified Gravity: the CMB, Weak Lensing and General Parameterisations: We examine general physical parameterisations for viable gravitational models in the $f(R)$ framework. This is related to the mass of an additional scalar field, called the scalaron, that is introduced by the theories. Using a simple parameterisatio...
Flow Patterns around Dark Matter Halos: the Link between Halo Dynamical Properties and Large Scale Tidal Field: We study how halo intrinsic dynamical properties are linked to their formation processes for halos in two mass ranges, $10^{12}-10^{12.5}h^{-1}{\rm M_\odot}$ and $\ge 10^{13}h^{-1}{\rm M_\odot}$, and how bo...
The LABOCA survey of the Extended Chandra Deep Field South: Two modes of star formation in AGN hosts?: We study the co-existence of star formation and AGN activity in X-ray selected AGN by analyzing stacked 870um submm emission from a deep and wide map of the Extended Chandra Deep Field South, obtained with LABOCA at...
Analysis of the impact of broad absorption lines on quasar redshift measurements with synthetic observations: Accurate quasar classifications and redshift measurements are increasingly important to precision cosmology experiments. Broad absorption line (BAL) features are present in 15-20\% of all quasars, and these f...
A self-consistent phase-space distribution function for the anisotropic Dark Matter halo of the Milky Way: Dark Matter (DM) direct detection experiments usually assume the simplest possible 'Standard Halo Model' for the Milky Way (MW) halo in which the velocity distribution is Maxwellian. This model assumes that the ...
Prediction of the Cosmic Evolution of the CO-Luminosity Functions: We predict the emission line luminosity functions (LFs) of the first 10 rotational transitions of CO in galaxies at redshift z=0 to z=10. This prediction relies on a recently presented simulation of the molecular cold gas content in ~3e7 evolving galaxi...
Dark Matter annihilations in halos and high-redshift sources of reionization of the universe: It is well known that annihilations in the homogeneous fluid of dark matter (DM) can leave imprints in the cosmic microwave background (CMB) anisotropy power spectrum. However, the relevance of DM annihilations in halos for ...
The Swift short gamma-ray burst rate density: implications for binary neutron star merger rates: Short gamma-ray bursts (SGRBs) observed by {\it Swift} are potentially revealing the first insight into cataclysmic compact object mergers. To ultimately acquire a fundamental understanding of these events requires pan-sp...
The Subaru Ly-alpha blob survey: A sample of 100 kpc Ly-alpha blobs at z=3: We present results of a survey for giant Ly-alpha nebulae (LABs) at z=3 with Subaru/Suprime-Cam. We obtained Ly-alpha imaging at z=3.09+-0.03 around the SSA22 protocluster and in several blank fields. The total survey area is 2.1 square degre...
From the cosmological model to generation of the Hubble flow: We review different approaches to the problem of generating the observed Hubble flow, whose discussion was pioneered by A.D. Sakharov. Extrapolating the Cosmological Standard Model to the past makes it possible to determine physical properties of and conditi...
On the EFT of Large Scale Structures in Redshift Space: We further develop the description of redshift space distortions within the Effective Field Theory of Large Scale Structures. First, we generalize the counterterms to include the effect of baryonic physics and primordial non-Gaussianity. Second, we evaluate the IR...
Evidence for departure from ΛCDM with LSS: We investigate the growth index parameter \gamma and the time variation of the gravitational constant G_{eff} by using the currently available growth function f(z) data at different redshifts, with and without scaling to the fiducial \Lambda CDM model. We inquire the four diff...
Inflation and Early Dark Energy with a Stage II Hydrogen Intensity Mapping Experiment: This white paper envisions a revolutionary post-DESI, post-LSST dark energy program based on intensity mapping of the redshifted 21cm emission line from neutral hydrogen at radio frequencies. The proposed intensity mapping survey h...
BBN And The CMB Constrain Neutrino Coupled Light WIMPs: (abridged) In the presence of a light WIMP (mass m_chi < 30 MeV), there are degeneracies among the WIMP's nature, its couplings to standard model particles, its mass, and the number of equivalent (additional) neutrinos, Delta N_nu. These degeneracies cannot be bro...
Constraints on the Nature of CID-42: Recoil Kick or Supermassive Black Hole Pair?: The galaxy CXOC J100043.1+020637, also known as CID-42, is a highly unusual object. An apparent galaxy merger remnant, it displays signatures of both an inspiraling, kiloparsec-scale active galactic nucleus (AGN) pair and of a recoilin...
The dust emission of high-redshift quasars: The detection of powerful near-infrared emission in high redshift (z>5) quasars demonstrates that very hot dust is present close to the active nucleus also in the very early universe. A number of high-redshift objects even show significant excess emission in the rest frame NI...
CMB anisotropies generated by cosmic string loops: We investigate the contribution of cosmic string loops to the Cosmic Microwave Background (CMB) anisotropies. This is done by extending the Unconnected Segment Model (USM) to include the contribution of the cosmic string loops created throughout the cosmological evolut...
Circular Polarization of the CMB: A probe of the First stars: While it is revealed that the Cosmic Microwave Background (CMB) is linearly polarized at 10 % level, it is predicted that there exists no significant intrinsic source for circular polarization (CP) in the standard cosmology. However, during the propagation t...
Interacting dark energy from the joint analysis of the power spectrum and bispectrum multipoles with the EFTofLSS: Interacting dark energy models have been suggested as alternatives to the standard cosmological model, $\Lambda$CDM. We focus on a phenomenologically interesting class of dark scattering models that is c...
Beyond dark energy Fisher forecasts: how DESI will constrain LCDM and quintessence models: We baseline with current cosmological observations to forecast the power of the Dark Energy Spectroscopic Instrument (DESI) in two ways: 1. the gain in constraining power of parameter combinations in the standard $\Lambda$CDM m...
Adaptively refined large eddy simulations of clusters: We present a numerical scheme for modelling unresolved turbulence in cosmological adaptive mesh refinement codes. As a first application, we study the evolution of turbulence in the intra-cluster medium and in the core of a galaxy cluster. Simulations with and with...
Constraints on primordial black holes as dark matter candidates from capture by neutron stars: We investigate constraints on primordial black holes (PBHs) as dark matter candidates that arise from their capture by neutron stars (NSs). If a PBH is captured by a NS, the star is accreted onto the PBH and gets destroyed ...
The Yukawa-Coupled Dark Sector Model and Cosmological Tensions: In this paper, we investigate the interaction between early dark energy (EDE) and cold dark matter, proposing a Yukawa-coupled dark sector model to mitigate cosmological tensions. We utilize the EDE component in the coupled model to relieve the Hubble tens...
A Detection of $z$~2.3 Cosmic Voids from 3D Lyman-$α$ Forest Tomography in the COSMOS Field: We present the most distant detection of cosmic voids ($z \sim 2.3$) and the first detection of three-dimensional voids in the Lyman-$\alpha$ forest. We used a 3D tomographic map of the absorption with effective comoving spat...
Loops abound in the cosmic microwave background: A $4σ$ anomaly on super-horizon scales: We present a topological analysis of the temperature fluctuation maps from the \emph{Planck 2020} Data release 4 (DR4) based on the \texttt{NPIPE} data processing pipeline. For comparison, we also present the topological characte...
Understanding caustic crossings in giant arcs: characteristic scales, event rates, and constraints on compact dark matter: The recent discovery of fast transient events near critical curves of massive galaxy clusters, which are interpreted as highly magnified individual stars in giant arcs due to caustic crossing, op...
New Light on Dark Extended Lenses with the Roman Space Telescope: The Roman Space Telescope's Galactic Bulge Time Domain Survey will constitute the most sensitive microlensing survey of the Galactic Bulge to date, opening up new opportunities to search for dark matter (DM). Many extensions of the Standard Model predict...
When Is Secular Evolution Important?: This abstract has been withdrawn. The proper replacement is arXiv:0909.3306
Statistical hierarchy of varying speed of light cosmologies: Variation of the speed of light is quite a debated issue in cosmology with some benefits, but also with some controversial concerns. Many approaches to develop a consistent varying speed of light (VSL) theory have been developed recently. Although a lot of th...
Subhaloes in Self-Interacting Galactic Dark Matter Haloes: We present N-body simulations of a new class of self-interacting dark matter models, which do not violate any astrophysical constraints due to a non-power-law velocity dependence of the transfer cross section which is motivated by a Yukawa-like new gauge boson ...
Precise limits on cosmological variability of the fine-structure constant with zinc and chromium quasar absorption lines: The strongest transitions of Zn and CrII are the most sensitive to relative variations in the fine-structure constant ($\Delta\alpha/\alpha$) among the transitions commonly observed in quasar abso...
Probing the Dawn of Galaxies at z~9-12: New Constraints from HUDF12/XDF and CANDELS Data: We present a comprehensive analysis of z>8 galaxies based on ultra-deep WFC3/IR data. We constrain the evolution of the UV luminosity function (LF) and luminosity densities from z~11 to z~8 by exploiting all the WFC3/IR data ove...
The Mid-IR Contribution Of Dust Enshrouded Stars In Six Nearby Galaxies: We measure the integrated contributions of dusty AGB stars and other luminous red mid-IR sources to the mid-IR luminosities of 6 galaxies (M81, NGC 2403, NGC 300, M33 and the Magellanic Clouds). We find the dusty AGB stars whose mid-IR fluxes are ...
Observational Constraints on Monomial Warm Inflation: Warm inflation is, as of today, one of the best motivated mechanisms for explaining an early inflationary period. In this paper, we derive and analyze the current bounds on warm inflation with a monomial potential $U\propto \phi^p$, using the constraints from the PL...
Solar Mass Primordial Black Holes in Moduli Dominated Universe: We explore the prospect of producing primordial black holes around the solar mass region during an early matter domination epoch. The early matter-dominated epoch can arise when a moduli field comes to dominate the energy density of the Universe prior to b...
Warm dark matter signatures on the 21cm power spectrum: Intensity mapping forecasts for SKA: We investigate the impact that warm dark matter (WDM) has in terms of 21cm intensity mapping in the post-reionization Universe at z = 3 - 5. We perform hydrodynamic simulations for 5 different models: cold dark matter and WDM...
By Dawn's Early Light: CMB Polarization Impact on Cosmological Constraints: Cosmic microwave background polarization encodes information not only on the early universe but also dark energy, neutrino mass, and gravity in the late universe through CMB lensing. Ground based surveys such as ACTpol, PolarBear, SPTpol sign...
Large-scale magnetic fields, non-Gaussianity, and gravitational waves from inflation: We explore the generation of large-scale magnetic fields in the so-called moduli inflation. The hypercharge electromagnetic fields couple to not only a scalar field but also a pseudoscalar one, so that the conformal invariance of th...
Dark energy by natural evolution: Constraining dark energy using Approximate Bayesian Computation: We look at dark energy from a biology inspired viewpoint by means of the Approximate Bayesian Computation (ABC) and late time cosmological observations. We find that dynamical dark energy comes out on top, or in the ABC...
The star cluster frequency throughout the Large Magellanic Cloud: We address the issue about the variation of the star cluster frequency (CF) in the Large Magellanic Cloud (LMC) in terms of the cluster spatial distribution. We adopted the LMC regions traced by Harris & Zaritsky (2009) and used an updated version of the...
What is the physical origin of strong Lya emission? II. Gas Kinematics and Distribution of Lya Emitters: We present a statistical study of velocities of Lya, interstellar (IS) absorption, and nebular lines and gas covering fraction for Lya emitters (LAEs) at z~2. We make a sample of 22 LAEs with a large Lya equivalen...
Potentialities of Hubble parameter and expansion rate function data to alleviate Hubble tension: Taking advantage of Gaussian process (GP), we obtain an improved estimate of the Hubble constant, $H_0=70.41\pm1.58$ km s$^{-1}$ Mpc$^{-1}$, using Hubble parameter [$H(z)$] from cosmic chronometers (CCH) and expansion rat...
Radial derivatives as a test of pre-Big-Bang events on the Planck data: Although the search for azimutal patterns in cosmological surveys is useful to characterise some effects depending exclusively on an angular distance within the standard model, they are considered as a key distinguishing feature of some exotic scen...
Intensity mapping of the 21cm emission: lensing: In this paper, we study lensing of 21cm intensity mapping (IM). Like in the cosmic microwave background (CMB), there is no first order lensing in intensity mapping. The first effects in the power spectrum are therefore of second and third order. Despite this, lensing of ...
A Search for Optical Variability of Type 2 Quasars in SDSS Stripe 82: Hundreds of Type 2 quasars have been identified in Sloan Digital Sky Survey (SDSS) data, and there is substantial evidence that they are generally galaxies with highly obscured central engines, in accord with unified models for active galactic nuclei...
Impact of Image Persistence in the Roman Space Telescope High-Latitude Survey: The High Latitude Survey of the Nancy Grace Roman Space Telescope is expected to measure the positions and shapes of hundreds of millions of galaxies in an area of 2220 deg$^2$. This survey will provide high-quality weak lensing data with ...
Bayesian large-scale structure inference and cosmic web analysis: Surveys of the cosmic large-scale structure carry opportunities for building and testing cosmological theories about the origin and evolution of the Universe. This endeavor requires appropriate data assimilation tools, for establishing the contact betwee...
Parity violation of primordial magnetic fields in the CMB bispectrum: We study the parity violation in the cosmic microwave background (CMB) bispectrum induced by primordial magnetic fields (PMFs). Deriving a general formula for the CMB bispectrum generated from not only non-helical but also helical PMFs, we find that ...
Moving mesh cosmology: properties of neutral hydrogen in absorption: We examine the distribution of neutral hydrogen in cosmological simulations carried out with the new moving-mesh code AREPO and compare it with the corresponding GADGET simulations based on the smoothed particle hydrodynamics (SPH) technique. The two ...
Baryon Acoustic Oscillations in the Lyman Alpha Forest: We use hydrodynamic cosmological simulations in a (600 Mpc)^3 volume to study the observability of baryon acoustic oscillations (BAO) in the intergalactic medium as probed by Lyman alpha forest (LAF) absorption. The large scale separation between the wavelength of...
Cosmological forecast of the 21-cm power spectrum using the halo model of reionization: The 21-cm power spectrum of reionization is a promising probe for cosmology and fundamental physics. Exploiting this new observable, however, requires fast predictors capable of efficiently scanning the very large parameter space ...
The PAU Survey: narrowband photometric redshifts using Gaussian processes: We study the performance of the hybrid template-machine-learning photometric redshift (photo-$z$) algorithm Delight, which uses Gaussian processes, on a subset of the early data release of the Physics of the Accelerating Universe Survey (PAUS)...
Stellar Populations of Lyman Alpha Emitters at z~6-7: Constraints on the Escape Fraction of Ionizing Photons from Galaxy Building Blocks: We investigate the stellar populations of Lyman alpha emitters (LAEs) at z=5.7 and 6.6 in a 0.65 deg^2 sky of the Subaru/XMM-Newton Deep Survey (SXDS) Field, using deep images take...
O-V-S-Z and friends: Non-Gaussianity from inhomogeneous reionization: We calculate the cosmic microwave background (CMB) bispectrum due to inhomogeneous reionization. We calculate all the terms that can contribute to the bispectrum that are products of first order terms on all scales in conformal Newtonian gauge. We al...
Scalar-Tensor Gravity Cosmology: Noether symmetries and analytical solutions: In this paper, we present a complete Noether Symmetry analysis in the framework of scalar-tensor cosmology. Specifically, we consider a non-minimally coupled scalar field action embedded in the FLRW spacetime and provide a full set of Noeth...
The Diversity of Core Halo Structure in the Fuzzy Dark Matter Model: In the fuzzy dark matter (FDM) model, gravitationally collapsed objects always consist of a solitonic core located within a virialised halo. Although various numerical simulations have confirmed that the collapsed structure can be described by a cored...
Modified gravity in Arnowitt-Deser-Misner formalism: Motivated by Horava-Lifshitz gravity theory, we propose and investigate two kinds of modified gravity theories, the f(R) kind and the K-essence kind, in the Arnowitt-Deser-Misner (ADM) formalism. The f(R) kind includes one ultraviolet (UV) term and one infrared (IR) ...
Evolution of the Sizes of Galaxies over 7<z<12 Revealed by the 2012 Hubble Ultra Deep Field Campaign: We analyze the redshift- and luminosity-dependent sizes of dropout galaxy candidates in the redshift range z~7-12 using deep images from the UDF12 campaign, data which offers two distinct advantages over that used in...
Insights into neutrino decoupling gleaned from considerations of the role of electron mass: We present calculations showing how electron rest mass influences entropy flow, neutrino decoupling, and Big Bang Nucleosynthesis (BBN) in the early universe. To elucidate this physics and especially the sensitivity of BBN and...
Constraining the distance to inspiralling NS-NS with Einstein Telescope: Einstein Telescope (ET) is a planned third generation gravitational waves detector located in Europe. Its design will be different from currently build interferometers, because ET will consist of three interferometers rotated by a 60 deg with resp...
On the Use of Ly-alpha Emitters as Probes of Reionization: We use numerical simulations to study the effects of the patchiness of a partly reionized intergalactic medium (IGM) on the observability of Ly-alpha emitters (LAEs) at high redshifts (z ~ 6). We present a new model that divides the Ly-alpha radiative transfer ...
Determining accurate measurements of the growth rate from the galaxy correlation function in simulations: We use high-resolution N-body simulations to develop a new, flexible, empirical approach for measuring the growth rate from redshift-space distortions (RSD) in the 2-point galaxy correlation function. We quantify...
Viscous Self Interacting Dark Matter and Cosmic Acceleration: Self interacting dark matter (SIDM) provides us with a consistent solution to certain astrophysical observations in conflict with collision-less cold DM paradigm. In this work we estimate the shear viscosity $(\eta)$ and bulk viscosity $(\zeta)$ of SIDM, wit...
A "Light," Centrally-Concentrated Milky Way Halo?: We discuss a novel approach to "weighing" the Milky Way dark matter halo, one that combines the latest samples of halo stars selected from the Sloan Digital Sky Survey (SDSS) with state-of-the-art numerical simulations of Milky Way analogs. The fully cosmological runs ...
Thermal blocking of preheating: The parametric resonance responsible for preheating after inflation will end when self-interactions of the resonating field and interactions of this field with secondary degrees of freedom become important. In many cases, the effect may be quantified in terms of an effective mass and the...
Cosmological Constraints from the double source plane lens SDSSJ0946+1006: We present constraints on the equation of state of dark energy, $w$, and the total matter density, $\Omega_{\mathrm{M}}$, derived from the double-source-plane strong lens SDSSJ0946+1006, the first cosmological measurement with a galaxy-scale d...
Do blue galaxy-clusters have hot intracluster gas?: We present herein a systematic X-ray analysis of blue galaxy-clusters at $z=0.84$ discovered by the Subaru telescope. The sample consisted of 43 clusters identified by combining red-sequence and blue-cloud surveys, covering a wide range of emitter fractions (i.e., 0.3...
The puzzling radio source in the cool core cluster A 2626: We report on new VLA radio observations performed at 1.4 GHz and 4.8 GHz with unprecedented sensitivity and angular resolution (~1 arcsec) of the cool core cluster A 2626, which is known to possess a radio mini-halo at its center. The most unusual features of A...
Scale dependence of the power spectrum of the curvature perturbation determined using a numerical method in slow-roll inflation: The Taylor expansion method has been used to investigate the scale dependence of the power spectrum of the curvature perturbation. In the present study, an alternative numerical method is u...
Cosmic Microwave Background Spectral Distortions from Cosmic String Loops: Cosmic string loops contain cusps which decay by emitting bursts of particles. A significant fraction of the released energy is in the form of photons. These photons are injected non-thermally and can hence cause spectral distortions of the Co...
Characterizing EoR foregrounds: A study of the Lockman Hole Region at 325 MHz: One of the key science goals for the most sensitive telescopes, both current and upcoming, is the detection of the redshifted 21-cm signal from the Cosmic Dawn and Epoch of Reionization. The success of detection relies on accurate foregrou...
Cross-tests of CMB features in the primordial spectra: The recent Planck data on the power spectrum of temperature anisotropies of the cosmic microwave background marginally support deviations from the $\Lambda$CDM model at several multipoles. With a view towards current and forthcoming observational surveys, we trace ...
Possibility of realizing weak gravity in redshift space distortion measurements: We study the possibility of realizing a growth rate of matter density perturbations lower than that in General Relativity. Using the approach of the effective field theory of modified gravity encompassing theories beyond Horndeski, we de...
The angular power spectrum measurement of the Galactic synchrotron emission in two fields of the TGSS survey: Characterizing the diffuse Galactic synchrotron emission at arcminute angular scales is needed to reliably remove foregrounds in cosmological 21-cm measurements. The study of this emission is also interesting...
High-redshift JWST Observations and Primordial Non-Gaussianity: Several bright and massive galaxy candidates at high redshifts have been recently observed by the James Webb Space Telescope. Such early massive galaxies seem difficult to reconcile with standard $\Lambda$ Cold Dark Matter model predictions. We discuss und...
Component separation for future CMB B-mode satellites: Next-generation CMB satellite concepts (LiteBIRD, CORE, PIXIE, PICO) are being proposed to detect the primordial CMB B-mode polarization at large angular scales in the sky for tensor-to-scalar ratio values of ${r \lesssim 10^{-3}}$. Yet undetected, primordial CMB B...
AGN feedback works both ways: Simulations of galaxy growth need to invoke strong negative feedback from active galactic nuclei (AGN) to suppress the formation of stars and thus prevent the over-production of very massive systems. While some observations provide evidence for such negative feedback, other studies find ei...
Using peculiar velocity surveys to constrain the growth rate of structure with the wide-angle effect: Amongst the most popular explanations for dark energy are modified theories of gravity. The galaxy overdensity and peculiar velocity fields help us to constrain the growth rate of structure and distinguish different ...
Interacting modified holographic Ricci dark energy model and statefinder diagnosis in flat universe: In this work we have considered the modified holographic Ricci dark energy interacting with dark matter through a non-gravitational coupling. We took three phenomenological forms for the interaction term $Q$ in the mo...
DEMNUni: Massive neutrinos and the bispectrum of large scale structures: The main effect of massive neutrinos on the large-scale structure consists in a few percent suppression of matter perturbations on all scales below their free-streaming scale. Such effect is of particular importance as it allows to constraint the ...
Variability in Quasar Broad Absorption Line Outflows: Broad absorption lines (BALs) in quasar spectra identify high velocity outflows that likely exist in all quasars and could play a major role in feedback to galaxy evolution. Studying the variability in these BALs can help us understand the structure, evolution, and ...
Polarization of the Cosmic Infrared Background Fluctuations: The cosmic infrared background (CIB) is slightly polarized. Polarization directions of individual galaxies could be aligned with tidal fields around galaxies, resulting in nonzero CIB polarization. We use a linear intrinsic alignment model to theoretically pr...
Probing the First Stars and Black Holes in the Early Universe with the Dark Ages Radio Explorer (DARE): A concept for a new space-based cosmology mission called the Dark Ages Radio Explore (DARE) is presented in this paper. DARE's science objectives include (1) When did the first stars form? (2) When did the first ac...
KAT-7 Science Verification: Using HI Observations of NGC 3109 to Understand its Kinematics and Mass Distribution: HI observations of the Magellanic-type spiral NGC 3109, obtained with the seven dish Karoo Array Telescope (KAT-7), are used to analyze its mass distribution. Our results are compared to what is obtained ...
Predicted properties of multiple images of the strongly lensed supernova SN Refsdal: We construct a mass model of the cluster MACS J1149.6+2223 to study the expected properties of multiple images of SN Refsdal, the first example of a gravitationally lensed supernova with resolved multiple images recently reported by ...
Hybrid SBI or How I Learned to Stop Worrying and Learn the Likelihood: We propose a new framework for the analysis of current and future cosmological surveys, which combines perturbative methods (PT) on large scales with conditional simulation-based implicit inference (SBI) on small scales. This enables modeling of a w...
Evidence of Gunn-Peterson damping wings in high-z quasar spectra: strengthening the case for incomplete reionization: The spectra of several high-redshift (z>6) quasars have shown evidence for a Gunn-Peterson (GP) damping wing, indicating a substantial mean neutral hydrogen fraction (x_HI > 0.03) in the z ~ 6 interga...
A comparison of the excess mass around CFHTLenS galaxy-pairs to predictions from a semi-analytic model using galaxy-galaxy-galaxy lensing: The matter environment of galaxies is connected to the physics of galaxy formation and evolution. Utilising galaxy-galaxy-galaxy lensing as a direct probe, we map out the distribu...
On Separate Universes: (abridged version) The separate universe conjecture states that in General Relativity a density perturbation behaves locally (i.e. on scales much smaller than the wavelength of the mode) as a separate universe with different background density and curvature. We prove this conjecture for a spheric...
Subaru medium-resolution spectra of a QSO at z=6.62: Three reionization tests: Investigating the Gunn-Peterson trough of high redshift quasars (QSOs) is a powerful way to reveal the cosmic reionization. As one of such attempts, we perform a series of analyses to examine the absorption lines observed with one of the h...
The physical scale of the far-infrared emission in the most luminous submillimetre galaxies II: evidence for merger-driven star formation: We present high-resolution 345 GHz interferometric observations of two extreme luminous (L_{IR}>10^{13} L_sun), submillimetre-selected galaxies (SMGs) in the COSMOS field with the...
Unlocking the secrets of stellar haloes using combined star counts and surface photometry: The stellar haloes of galaxies can currently be studied either through observations of resolved halo stars or through surface photometry. Curiously, the two methods appear to give conflicting results, as a number of surface pho...
Dust-obscured star-formation in the outskirts of XMMU J2235.3-2557, a massive galaxy cluster at z=1.4: Star-formation in the galaxy populations of local massive clusters is reduced with respect to field galaxies, and tends to be suppressed in the core region. Indications of a reversal of the star-formation--density r...
Low-mass stars within dense dark matter halos: We studied the formation and evolution of low-mass stars within halos with high concentration of dark matter (DM) particles, using a highly sophisticated expression to calculate the rate at which DM particles are captured inside the star. For very high DM densities in the ...
Testing isotropy in the Two Micron All-Sky redshift survey with information entropy: We use information entropy to test the isotropy in the nearby galaxy distribution mapped by the Two Micron All-Sky redshift survey (2MRS). We find that the galaxy distribution is highly anisotropic on small scales. The radial anisotr...
Can residuals of the Solar system foreground explain low multipole anomalies of the CMB ?: The low multipole anomalies of the Cosmic Microwave Background has received much attention during the last few years. It is still not ascertained whether these anomalies are indeed primordial or the result of systematics or for...
Testing Dark Energy Models with Gamma-Ray Bursts Calibrated from the Observational $H(z)$ Data through a Gaussian Process: We use a cosmology-independent method to calibrate gamma-ray burst (GRB) from the observational Hubble data (OHD) with the cosmic chronometers method. By using Gaussian Process to reconstruct OHD...
Even Lighter Particle Dark Matter: We report on recent progress in the search for dark matter particles with masses from 1 MeV to 1 GeV. Several dark matter candidates in this mass range are expected to generate measurable electronic-recoil signals in direct-detection experiments. We focus on dark matter particles scat...
The cosmology dependence of the concentration-mass-redshift relation: The concentrations of dark matter haloes provide crucial information about their internal structure and how it depends on mass and redshift -- the so-called concentration-mass-redshift relation, denoted $c(M,z)$. We present here an extensive study of...
An Oxygen Abundance Gradient into the Outer Disk of M81: The extended HI disk and tidal tails of M81 present an interesting environment to study the effects of galaxy interaction on star formation and chemical evolution of the outer disk of a large spiral galaxy. We present H{\alpha} imaging of the outer disk of M81 an...
Cosmic Filament Spin from Dark Matter Vortices: The recent observational evidence for cosmic filament spin on megaparsec scales (Wang et al, Nature Astronomy 5, 839-845 (2021)) demands an explanation in the physics of dark matter. Conventional collisionless cold particle dark matter is conjectured to generate cosmic fi...
Can Light Dark Matter Solve the Core-Cusp Problem?: Recently there has been much interest in light dark matter, especially ultra-light axions, as they may provide a solution to the core-cusp problem at the center of galaxies. Since very light bosons can have a de Broglie wavelength that is of astrophysical size, they c...
Are Scalar and Tensor Deviations Related in Modified Gravity?: Modified gravity theories on cosmic scales have three key deviations from general relativity. They can cause cosmic acceleration without a physical, highly negative pressure fluid, can cause a gravitational slip between the two metric potentials, and can ca...
Modeling quasar accretion disc temperature profiles: Microlensing observations indicate that quasar accretion discs have half-light radii larger than expected from standard theoretical predictions based on quasar fluxes or black hole masses. Blackburne and colleagues have also found a very weak wavelength dependence of...
Constraining gravity with synergies between radio and optical cosmological surveys: In this work we present updated forecasts on parameterised modifications of gravity that can capture deviations of the behaviour of cosmological density perturbations beyond $\Lambda$CDM. For these forecasts we adopt the SKA Observato...
SN 2003bg: The First Type IIb Hypernova: Optical and near-infrared photometry and optical spectroscopy are reported for SN 2003bg, starting a few days after explosion and extending for a period of more than 300 days. Our early-time spectra reveal the presence of broad, high-velocity Balmer lines. The nebular-phase spec...
Inhomogeneous cosmological models and $H_0$ observations: We address some recent erroneous claim that $H_0$ observations are difficult to accommodate with LTB cosmological models, showing how to construct solutions in agreement with an arbitrary value of $H_0$ by re-writing the exact solution in terms of dimensionless ...
Standard candles and sirens rescue $H_0$: We show that future observations of binary neutron star systems with electromagnetic counterparts together with the traditional probes of low- and high-redshift Type Ia supernovae (SNe Ia) can help resolve the Hubble tension. The luminosity distance inferred from these probes a...
Weak lensing in non-statistically isotropic universes: The Bipolar Spherical Harmonics (BipoSH) form a natural basis to study the CMB two point correlation function in a non-statistically isotropic (non-SI) universe. The coefficients of expansion in this basis are a generalisation of the well known CMB angular power sp...
On the Stellar Populations and Evolution of Star-Forming Galaxies at 6.3 < z < 8.6: We study the physical characteristics of galaxies at 6.3 < z < 8.6, selected from deep near-infrared imaging with the Wide Field Camera 3 (WFC3) on board the Hubble Space Telescope. Accounting for the photometric scatter using simulat...
Graviton non-Gaussianities and Parity Violation in the EFT of Inflation: We study graviton non-Gaussianities in the EFT of Inflation. At leading (second) order in derivatives, the graviton bispectrum is fixed by Einstein gravity. There are only two contributions at third order. One of them breaks parity. They come from...
Galaxy clustering in the NEWFIRM Medium Band Survey: the relationship between stellar mass and dark matter halo mass at 1 < z < 2: We present an analysis of the clustering of galaxies as a function of their stellar mass at 1 < z < 2 using data from the NEWFIRM Medium Band Survey (NMBS). The precise photometric redshi...
The massive elliptical galaxy NGC 4649 from the perspective of extended gravity: Elliptical galaxies are systems where dark matter is usually less necessary to explain observed dynamics than in the case of spiral galaxies, however there are some instances where Newtonian gravity and the observable mass are insufficie...
Improving initialization and evolution accuracy of cosmological neutrino simulations: Neutrino mass constraints are a primary focus of current and future large-scale structure (LSS) surveys. Non-linear LSS models rely heavily on cosmological simulations -- the impact of massive neutrinos should therefore be included ...
Connecting stellar mass and star-formation rate to dark matter halo mass out to z ~ 2: We have constructed an extended halo model (EHM) which relates the total stellar mass and star-formation rate (SFR) to halo mass (M_h). An empirical relation between the distribution functions of total stellar mass of galaxies and ...
The Survey of Extragalactic Nuclear Spectral Energies: We present the first results from the new Survey of Extragalactic Nuclear Spectral Energies (SENSE) sample of "blazars". The sample has been chosen with minimal selection effects and is therefore ideal to probe the intrinsic properties of the blazar population. We ...
Holographic Ricci dark energy: Current observational constraints, quintom feature, and the reconstruction of scalar-field dark energy: In this work, we consider the cosmological constraints on the holographic Ricci dark energy proposed by Gao et al. [Phys. Rev. D 79, 043511 (2009)], by using the observational data cu...
A measurement of galaxy halo mass from the surrounding HI Lyα absorption: We measure the dark matter halo masses of z~2.36 UV color-selected star-forming galaxies by matching the observed median HI Ly{\alpha} absorption around them, as observed in the spectra of background QSOs, to the absorption around haloes above ...
Constraining high-redshift stellar-mass primordial black holes with next-generation ground-based gravitational-wave detectors: The possible existence of primordial black holes in the stellar mass window has received considerable attention because their mergers may contribute to current and future gravitational-wave d...
The angular momentum of baryons and dark matter halos revisited: Recent theoretical studies have shown that galaxies at high redshift are fed by cold, dense gas filaments, suggesting angular momentum transport by gas differs from that by dark matter. Revisiting this issue using high-resolution cosmological hydrodynamic...
Evolution of the Fundamental Plane of 0.2<z<1.2 Early-type galaxies in the EGS: The Fundamental Plane relates the structural properties of early-type galaxies such as its surface brightness and effective radius with its dynamics. The study of its evolution has therefore important implications for models of galaxy for...
The Linear Growth of Structure in the R_h=ct Universe: We use recently published redshift space distortion measurements of the cosmological growth rate, f sigma_8(z), to examine whether the linear evolution of perturbations in the R_h=ct cosmology is consistent with the observed development of large scale structure. We...
Oscillon formation from preheating in asymmetric inflationary potentials: We investigate the possibility of oscillon formation during the preheating phase of asymmetric inflationary potentials. We analytically establish the existence of oscillon-like solutions for the Klein-Gordon equation for a polynomial potential of...
The source counts of submillimetre galaxies detected at 1.1 mm: The source counts of galaxies discovered at sub-millimetre and millimetre wavelengths provide important information on the evolution of infrared-bright galaxies. We combine the data from six blank-field surveys carried out at 1.1 mm with AzTEC, totalling 1...
A hydrodynamical halo model for weak-lensing cross correlations: On the scale of galactic haloes, the distribution of matter in the cosmos is affected by energetic, non-gravitational processes; so-called baryonic feedback. A lack of knowledge about the details of how feedback processes redistribute matter is a source o...
Observational constraints on dark matter scattering with electrons: We present new observational constraints on the elastic scattering of dark matter with electrons for dark matter masses between 10 keV and 1 TeV. We consider scenarios in which the momentum-transfer cross section has a power-law dependence on the relat...
A practical guide to the massive black hole cosmic history: I review our current understanding of massive black hole (MBH) formation and evolution along the cosmic history. After a brief introductory overview of the relevance of MBHs in the hierarchical structure formation paradigm, I discuss the main viable channels f...
Continuous matter creation and the acceleration of the universe: a replay: In a recent note (arXiv:1012.5069), the investigation performed by the present authors on the evolution of density fluctuations in an accelerated universe including matter creation was criticized. The criticism is based on the fact that the Ne...
Double inflation via non-minimally coupled spectator: We argue that double inflation may occur when a spectator field is non-minimally coupled to gravity. As a concrete example, we study a two-field inflationary model where the initial spectator field is non-minimally coupled to gravity while the initial inflaton field...
Gravitational Stability of Vortices in Bose-Einstein Condensate Dark Matter: We investigate a simple model for a galactic halo under the assumption that it is dominated by a dark matter component in the form of a Bose-Einstein condensate involving an ultra-light scalar particle. In particular we discuss the possibili...
Galaxy power spectrum and biasing results from the LOFAR Two-metre Sky Survey (first data release): The LOFAR Two-metre Sky Survey (LoTSS) is an ongoing survey aiming to observe the entire Northern sky, providing an excellent opportunity to study the distribution and evolution of the large-scale structure of the Univ...
Helical magnetic fields in the M87 jet at arc-second scales: We investigate the magnetic field configuration of the M87 jet at arc-second scales by using archival polarimetric VLA data at 8, 15, 22 and 43 GHz. By stacking images over three years in order to enhance the sensitivity, we reveal, for the first time, system...
WEAVE-QSO: A Massive Intergalactic Medium Survey for the William Herschel Telescope: In these proceedings we describe the WEAVE-QSO survey, which will observe around 400,000 high redshift quasars starting in 2018. This survey is part of a broader WEAVE survey to be conducted at the 4.2m William Herschel Telescope. We...
The Dark Energy Survey 5-year photometrically identified Type Ia Supernovae: As part of the cosmology analysis using Type Ia Supernovae (SN Ia) in the Dark Energy Survey (DES), we present photometrically identified SN Ia samples using multi-band light-curves and host galaxy redshifts. For this analysis, we use the ph...
Cosmological parameter estimation with future gravitational wave standard siren observation from the Einstein Telescope: In this work, we use the simulated gravitational wave (GW) standard siren data from the future observation of the Einstein Telescope (ET) to constrain various dark energy cosmological models, inclu...
Prospects for measuring the relative velocities of galaxy clusters in photometric surveys using the kinetic Sunyaev-Zel'dovich Effect: We consider the prospects for measuring the pairwise kinetic Sunyaev-Zel'dovich (kSZ) signal from galaxy clusters discovered in large photometric surveys such as the Dark Energy Surve...
COSMOS: Stochastic bias from measurements of weak lensing and galaxy clustering: In the theory of structure formation, galaxies are biased tracers of the underlying matter density field. The statistical relation between galaxy and matter density field is commonly referred as galaxy bias. In this paper, we test the li...
Localised HI 21-cm absorption towards a double-lobed z=0.24 radio galaxy: We present the results of a mini-survey for associated HI 21-cm absorption at z < 0.42 with the Giant Metrewave Radio Telescope. Our targets are radio galaxies, selected on the basis that the 1216 Angstrom luminosities are below 10^23 W/Hz, above...
Gas Sloshing and Radio Galaxy Dynamics in the Core of the 3C449 Group: We present results from a 140 ks Chandra/ACIS-S observation of the hot gas around the canonical FR I radio galaxy 3C 449. An earlier, shorter 30 ks Chandra observation of the group gas showed an unusual entropy distribution and a surface brightness ...
Generic inference of inflation models by non-Gaussianity and primordial power spectrum reconstruction: We present a generic inference method for inflation models from observational data by the usage of higher-order statistics of the curvature perturbation on uniform density hypersurfaces. This method is based on the ...
Integrated Cosmological Probes: Extended Analysis: Recent progress in cosmology has relied on combining different cosmological probes. In earlier work, we implemented an integrated approach to cosmology where the probes are combined into a common framework at the map level. This has the advantage of taking full account...
Flat-Sky Pseudo-Cls Analysis for Weak Gravitational Lensing: We investigate the use of estimators of weak lensing power spectra based on a flat-sky implementation of the Pseudo-Cl (PCl) technique, where the masked shear field is transformed without regard for masked regions of sky. This masking mixes power, and E-conve...
DBI Galileon and Late time acceleration of the universe: We consider 1+3 dimensional maximally symmetric Minkowski brane embedded in a 1+4 dimensional maximally symmetric Minkowski background. The resulting 1+3 dimensional effective field theory is of DBI (Dirac-Born-Infeld) Galileon type. We use this model to study th...
Galaxy Infall Kinematics as a Test of Modified Gravity: Infrared modifications of General Relativity (GR) can be revealed by comparing the mass of galaxy clusters estimated from weak lensing to that from infall kinematics. We measure the 2D galaxy velocity distribution in the cluster infall region by applying the galax...
Flow-Based Likelihoods for Non-Gaussian Inference: We investigate the use of data-driven likelihoods to bypass a key assumption made in many scientific analyses, which is that the true likelihood of the data is Gaussian. In particular, we suggest using the optimization targets of flow-based generative models, a class o...
A Keck/DEIMOS spectroscopic survey of the faint M31 satellites And IX, And XI, And XII, and And XIII: We present the first spectroscopic analysis of the faint M31 satellite galaxies, AndXI and AndXIII, and a reanalysis of existing spectroscopic data for two further faint companions, And IX and AndXII. By combining da...
Density perturbations for running vacuum: a successful approach to structure formation and to the $σ_8$-tension: Recent studies suggest that dynamical dark energy (DDE) provides a better fit to the rising affluence of modern cosmological observations than the concordance model ($\Lambda$CDM) with a rigid cosmological...
Accurate modelling of the Lyman-$α$ coupling for the 21-cm signal, observability with NenuFAR and SKA: The measurement of the $21$ cm signal from the Cosmic Dawn is a major goal for several existing and upcoming radio interferometers such as NenuFAR and the SKA. During this era before the beginning of the Epoch of Re...
Long Gamma-Ray Burst Host Galaxies and their Environments: In this book-chapter we first briefly discuss some basic observational issues related to what a GRB host galaxy is (whether they are operationally well defined as a class) and sample completeness. We then describe some of the early studies of GRB hosts starting...
Determining dust temperatures and masses in the Herschel era: the importance of observations longward of 200 micron: The properties of the dust grains (e.g., temperature and mass) can be derived from fitting far-IR SEDs (>100 micron). Only with SPIRE on Herschel has it been possible to get high spatial resolution at ...
Subhalo effective density slope measurements from HST strong lensing data with neural likelihood-ratio estimation: Examining the properties of subhalos with strong gravitational lensing images can shed light on the nature of dark matter. From upcoming large-scale surveys, we expect to discover orders of magnitude mor...
Multicolour-metallicity Relations from Globular Clusters in NGC 4486 (M87): We present Gemini griz photometry for 521 globular cluster (GC) candidates in a 5.5 x 5.5 arcmin field centered 3.8 arcmin to the south and 0.9 arcmin to the west of the center of the giant elliptical galaxy NGC 4486. All these objects have p...
Does the Hubble constant tension call for new physics?: The $\Lambda$ Cold Dark Matter model ($\Lambda$CDM) represents the current standard model in cosmology. Within this, there is a tension between the value of the Hubble constant, $H_0$, inferred from local distance indicators and the angular scale of fluctuations i...
Small-scale systems of galaxies. IV. Searching for the faint galaxy population associated with X-ray detected isolated E+S pairs: In hierarchical evolutionary scenarios, isolated, physical pairs may represent an intermediate phase, or "way station", between collapsing groups and isolated elliptical (E) galaxies (or f...
A novel variability-based method for quasar selection: evidence for a rest frame ~54 day characteristic timescale: We compare quasar selection techniques based on their optical variability using data from the Catalina Real-time Transient Survey (CRTS). We introduce a new technique based on Slepian wavelet variance (S...
Superdense Massive Galaxies in Wings Local Clusters: Massive quiescent galaxies at z>1 have been found to have small physical sizes, hence to be superdense. Several mechanisms, including minor mergers, have been proposed for increasing galaxy sizes from high- to low-z. We search for superdense massive galaxies in the W...
Einstein's legacy in galaxy surveys: Non-Gaussianity in the primordial fluctuations that seeded structure formation produces a signal in the galaxy power spectrum on very large scales. This signal contains vital information about the primordial Universe, but it is very challenging to extract, because of cosmic variance...
Damped Lyman-alpha absorbers as a probe of stellar feedback: We examine the abundance, clustering and metallicity of Damped Lyman-alpha Absorbers (DLAs) in a suite of hydrodynamic cosmological simulations using the moving mesh code AREPO. We incorporate models of supernova and AGN feedback, as well as molecular hydroge...
One-Dimensional Fuzzy Dark Matter Models: Structure Growth and Asymptotic Dynamics: This paper investigates the feasibility of simulating Fuzzy Dark Matter (FDM) with a reduced number of spatial dimensions. Our aim is to set up a realistic, yet numerically inexpensive, toy model in $(1+1)$-dimensional space time, tha...
Statistical Properties of Multi-epoch Spectral Variability of SDSS Stripe82 Quasars: We investigate the UV-optical (longward of Ly$\alpha$ 1216\AA) spectral variability of nearly 9000 quasars ($0<z<4$) using multi-epoch photometric data within the SDSS Stripe 82 region. The regression slope in the flux-flux space of ...
Gravitational waves from bubble collisions: analytic derivation: We consider gravitational wave production by bubble collisions during a cosmological first-order phase transition. In the literature, such spectra have been estimated by simulating the bubble dynamics, under so-called thin-wall and envelope approximations...
LBQS 0103-2753: A Binary Quasar in a Major Merger: We present HST and UKIRT spectra and images of the 2 kpc binary quasar LBQS 0103-2753 (z=0.858). The HST images (V- and I-band) show tidal features demonstrating that this system is a major galaxy merger in progress. A two-color composite image brings out knots of star...
$α$ attractors in Quintessential Inflation motivated by Supergravity: An exponential kind of quintessential inflation potential motivated by supergravity is studied. This type belongs to the class of {\alpha}-attractor models. The model was studied for the first time by Dimopoulos and Owen in [J. Cosmol. Astropart. P...
Dynamics of Scalar Field Dark Matter With a Cosh-like Potential: The dynamics of a cosmological model fueled by scalar field dark matter with a cosh-like potential plus a cosmological constant is investigated in detail. It is revealed that the late-time attractor is always the de Sitter solution, and that, depending on...
Observational Evidence Against Long-Lived Spiral Arms in Galaxies: We test whether the spiral patterns apparent in many large disk galaxies should be thought of as dynamical features that are stationary in a co-rotating frame for > t_{dyn}, as implied by the density wave approach for explaining spiral arms. If such spi...
Capse.jl: efficient and auto-differentiable CMB power spectra emulation: We present Capse.jl, a novel neural network-based emulator designed for rapid and accurate prediction of Cosmic Microwave Background (CMB) temperature, polarization, and lensing angular power spectra. The emulator computes predictions in just a fe...
An Atlas of Galaxy Spectral Energy Distributions from the Ultraviolet to the Mid-Infrared: We present an atlas of 129 spectral energy distributions for nearby galaxies, with wavelength coverage spanning from the UV to the mid-infrared. Our atlas spans a broad range of galaxy types, including ellipticals, spirals, mer...
Exploring the Galaxy Mass-Metallicity Relation at z~3-5: Long-duration gamma-ray bursts (GRBs) provide a premier tool for studying high-redshift star-forming galaxies thanks to their extreme brightness and association with massive stars. Here we use GRBs to study the galaxy stellar mass-metallicity (M*-Z) relation at z...
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...
Effects of thermal inflation on small scale density perturbations: In cosmological scenarios with thermal inflation, extra eras of moduli matter domination, thermal inflation and flaton matter domination exist between primordial inflation and the radiation domination of Big Bang nucleosynthesis. During these eras, cosm...
Cosmic slowing down of acceleration for several dark energy parametrizations: We further investigate slowing down of acceleration of the universe scenario for five parametrizations of the equation of state of dark energy using four sets of supernovae data. In a maximal probability analysis we also use the baryon acou...
Fast LiH destruction in reaction with H: quantum calculations and astrophysical consequences: We present a quantum-mechanical study of the exothermic 7LiH reaction with H. Accurate reactive probabilities and rate coefficients are obtained by solving the Schrodinger equation for the motion of the three nuclei on a sin...
Comparative Analysis of TRGBs (CATs) from Unsupervised, Multi-Halo-Field Measurements: Contrast is Key: The Tip of the Red Giant Branch (TRGB) is an apparent discontinuity in the color-magnitude diagram (CMD) along the giant branch due to the end of the red giant evolutionary phase and is used to measure distances in...
Dark-ages Reionization and Galaxy Formation Simulation XX. The Ly$α$ IGM transmission properties and environment of bright galaxies during the Epoch of Reionization: The highly neutral inter-galactic medium (IGM) during the Epoch of Reionization (EoR) is expected to suppress Ly$\alpha$ emission with damping-wing ab...
Constraining the inflationary potential with spectral distortions: Measuring spectral distortions (SDs) of the cosmic microwave background (CMB) will provide new constraints on previously unexplored scales of the primordial power spectrum, allowing us to extend the probed parameter space by several orders of magnitude ...
Using galaxy pairs as cosmological tracers: The Alcock-Paczynski (AP) effect uses the fact that, when analyzed with the correct geometry, we should observe structure that is statistically isotropic in the Universe. For structure undergoing cosmological expansion with the background, this constrains the product of the H...
Efficiency of pseudo-spectrum methods for estimation of Cosmic Microwave Background B-mode power spectrum: Estimation of the B-mode angular power spectrum of polarized anisotropies of the cosmic microwave background (CMB) is a key step towards a full exploitation of the scientific potential of this probe. In the cont...
Seeing in the dark -- II. Cosmic shear in the Sloan Digital Sky Survey: Statistical weak lensing by large-scale structure -- cosmic shear -- is a promising cosmological tool, which has motivated the design of several large upcoming surveys. Here, we present a measurement of cosmic shear using coadded Sloan Digital Sky ...
Relativistic collapse and explosion of rotating supermassive stars with thermonuclear effects: We present results of general relativistic simulations of collapsing supermassive stars with and without rotation using the two-dimensional general relativistic numerical code Nada, which solves the Einstein equations writt...
Multi-Messenger Astrophysics with the Cosmic Neutrino Background: The massive neutrinos of the Cosmic Neutrino Background (C$\nu$B) are fundamental ingredients of the radiation-dominated early universe and are important non-relativistic probes of the large-scale structure formation in the late universe. The dominant so...
Multi-Frequency Optical-Depth Maps and the Case for Free-Free Absorption in Two Compact Symmetric Radio Sources: the CSO candidate J1324+4048 and the CSO J0029+3457: We obtained dual-polarization VLBI observations at six frequencies of the compact symmetric object J0029+3457 and the CSO candidate J1324+4048. By com...
Cosmological particle-in-cell simulations with ultralight axion dark matter: We study cosmological structure formation with ultralight axion dark matter, or "fuzzy dark matter (FDM), using a particle-mesh scheme to account for the quantum pressure arising in the Madelung formulation of the Schr\"odinger-Poisson equat...
Vibrationally excited HC3N in NGC 4418: We investigate the molecular gas properties of the deeply obscured luminous infrared galaxy NGC 4418. We address the excitation of the complex molecule HC3N to determine whether its unusually luminous emission is related to the nature of the buried nuclear source. We use IRAM 30m...
Primordial quantum nonequilibrium and large-scale cosmic anomalies: We study incomplete relaxation to quantum equilibrium at long wavelengths, during a pre-inflationary phase, as a possible explanation for the reported large-scale anomalies in the cosmic microwave background (CMB). Our scenario makes use of the de Brog...
Emergence of the Temperature-Density Relation in the Low Density Intergalactic Medium: We examine the evolution of the phase diagram of the low-density intergalactic medium (IGM) during the Epoch of Reionization in simulation boxes with varying reionization histories from the Cosmic Reionization on Computers project....
Dynamical friction in cuspy galaxies: In this paper we treat the problem of the dynamical friction decay of a massive object moving in an elliptical galaxy with a cuspidal inner distribution of the mass density. We present results obtained by both self-consistent, direct summation, N-body simulations, as well as by a n...
Test of the cosmic evolution using Gaussian processes: Much focus was on the possible slowing down of cosmic acceleration under the dark energy parametrization. In the present paper, we investigate this subject using the Gaussian processes (GP), without resorting to a particular template of dark energy. The reconstruct...
Constraints on Dark Matter-Photon Coupling in the Presence of Time-Varying Dark Energy: In a recent work [Phys. Rev. D 98, 043521 (2018)], we have investigated a dark matter (DM)-photon coupling model in which the DM decays into photons in the presence of dark energy (DE) with the constant equation of state (EoS) par...
On the Dynamics of Non-Relativistic Flavor-Mixed Particles: Evolution of a system of interacting non-relativistic quantum flavor-mixed particles is considered both theoretically and numerically. It was shown that collisions of mixed particles not only scatter them elastically, but can also change their mass eigenstates...
Time Variable Cosmological Constant from Renormalization Group Equations: In this paper, a time variable cosmological constant (CC) from renormalization group equations (RGEs) is explored, where the renormalization scale $\mu^2=R^{-2}_{CC}=Max(\dot{H}+2H^2,-\dot{H})$ is taken. The cosmological parameters, such as dimen...
Image simulations for strong and weak gravitational lensing: Gravitational lensing has been identified as a powerful tool to address fundamental problems in astrophysics at different scales, ranging from exoplanet identification to dark energy and dark matter characterization in cosmology. Image simulations have played...