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Optical analysis of a CMB cosmic string candidateFeb 21 2019The complexity of the cosmological scenario regarding cosmic strings (CSs) stands still in the way of a complete understanding. We describe here a promising strategy for the possible detection of these elusive physical entities. It is based on the search ... More

Nonlocal Cosmology II --- Cosmic acceleration without fine tuning or dark energyFeb 21 2019We present an improved version of our original cosmological model to explain the current phase of cosmological acceleration without resorting to a cosmological constant or any other mass scale. Like the original, this phenomenological approach is based ... More

Cosmological Magnetic Field and Dark Energy as two sides of the same coinFeb 20 2019It has been recently argued \cite{Barvinsky:2017lfl} that the de Sitter phase in cosmology might be naturally generated as a result of dynamics of the topologically nontrivial sectors in a strongly coupled QCD-like gauge theory in expanding universe. ... More

Comment on "Optimal prior for Bayesian inference in a constrained parameter space" by S. Hannestad and T. Tram, arXiv:1710.08899Feb 20 2019The Jeffreys prior for a constrained part of a parameter space is the same as that for the unconstrained space, contrary to the assertions of Hannestad and Tram.

A multifiltering study of turbulence in a large sample of simulated galaxy clustersFeb 19 2019We present results from a large set of N-body/SPH hydrodynamical cluster simulations aimed at studying the statistical properties of turbulence in the ICM. The numerical hydrodynamical scheme employs a SPH formulation in which gradient errors are strongly ... More

Isotropic charged cosmologies in infrared-modified electrodynamicsFeb 19 2019It has long been known that the covariant formulation of quantum electrodynamics conflicts with the local description of states in the charged sector. Some of the solutions to this problem amount to modifications of the subsidiary conditions below some ... More

Percent-Level Test of Isotropic Expansion Using Type Ia SupernovaeFeb 19 2019We propose and implement a novel, robust, and non-parametric test of statistical isotropy of the expansion of the universe, and apply it to around one thousand type Ia supernovae from the Pantheon sample. We calculate the angular clustering of supernova ... More

The local and distant Universe: stellar ages and $H_0$Feb 19 2019The ages of the oldest stellar objects in our galaxy provide an independent test of the current cosmological model as they give a lower limit to the age of the Universe. Recent accurate parallaxes by the Gaia space mission, accurate measurements of the ... More

Gravitational lensing at milliarcsecond angular resolution with VLBI observationsFeb 19 2019Gravitational lensing is a powerful tool for quantifying the mass content and distribution in distant galaxies. By using milliarcsecond angular resolution observations of radio-loud gravitationally lensed sources it is also possible to detect and quantify ... More

Constraining the era of helium reionization using fast radio burstsFeb 19 2019The discovery of fast radio bursts (FRBs) about a decade ago opened up new possibilities for probing the ionization history of the Intergalactic Medium (IGM). In this paper we study the use of FRBs for tracing the epoch of HeII reionization, using simulations ... More

Measuring gravity at cosmological scalesFeb 19 2019This paper is a pedagogical introduction to models of gravity and how to constrain them through cosmological observations. We focus on the Horndeski scalar-tensor theory and on the quantities that can be measured with a minimum of assumptions. Alternatives ... More

The halo mass of optically-luminous quasars at z=1-2 measured via gravitational deflection of the cosmic microwave backgroundFeb 19 2019We measure the average deflection of cosmic microwave background photons by quasars at $\langle z \rangle =1.7$. Our sample is selected from the Sloan Digital Sky Survey to cover the redshift range $0.9\leq z\leq2.2$ with absolute i-band magnitudes of ... More

Chandra observations of the Abell S0295 clusterFeb 18 2019We present deep ($205 \rm ks$), \Chandra observations of the \ab295 binary merging cluster ($z=0.30$). In the X-ray image, the secondary component is clearly visible as a surface brightness peak, while the primary cluster has a flatter distribution. We ... More

NIHAO XVIII: Origin of the MOND phenomenology of galactic rotation curves in a LCDM universeFeb 18 2019The phenomenological basis for Modified Newtonian Dynamics (MOND) is the radial-acceleration-relation (RAR) between the observed acceleration, $a=V^2_{rot}(r)/r$, and the acceleration accounted for by the observed baryons (stars and cold gas), $a_{bar}=V_{bar}^2(r)/r$. ... More

Gravitational perturbations from oscillons and transients after inflationFeb 18 2019We study the scalar and tensor perturbations generated by the fragmentation of the inflaton condensate into oscillons or transients after inflation, using nonlinear classical lattice simulations. Without including the backreaction of metric perturbations, ... More

Does the second law hold at cosmic scales?Feb 18 2019The second law of thermodynamics is known to hold at small scales also when gravity plays a leading role, as in the case of black holes and self-gravitating radiation spheres. It has been suggested that it should as well at large scales. Here, by a purely ... More

A gauge invariant prescription to avoid $γ$-crossing instability in Galileon bounceFeb 18 2019We revisit the evolutions of scalar perturbations in a non-singular Galileon bounce. It is known that the second order differential equation governing the perturbations is numerically unstable at a point called $\gamma$-crossing. This instability is usually ... More

Point Source Detection and False Discovery Rate Control on CMB MapsFeb 18 2019We discuss a new procedure to search for point sources in Cosmic Microwave background maps; in particular, we aim at controlling the so-called False Discovery Rate, which is defined as the expected value of false discoveries among pixels which are labelled ... More

The linear bias of radio galaxies at z~0.3 via cosmic microwave background lensingFeb 18 2019We present a new measurement of the linear bias of radio loud active galactic nuclei (RLAGN) at $z\approx0.3$ and $L_{\rm 1.4GHz}>10^{23}\,{\rm W\,Hz^{-1}}$ selected from the Best & Heckman (2012) sample, made by cross-correlating the RLAGN surface density ... More

Round Table on Axions and Axion-like ParticlesFeb 18 2019In this contribution, based on the discussion at a round table of the XIII Quark Confinement and the Hadron Spectrum - Confinement conference, we review the main properties of the QCD axion and, more generally, of axion-like particles and their relevance ... More

Bounce cosmology in generalized modified gravitiesFeb 18 2019We investigate the bounce realization in the framework of generalized modified gravities arising from Finsler and Finsler-like geometry. In particular, the richer intrinsic geometrical structure is reflected in the appearance of extra degrees of freedom ... More

Homogeneity of the universe emerging from the Equivalence Principle and Poisson equation: A comparison between Newtonian and MONDian cosmologyFeb 18 2019A correspondence between the Equivalence principle and the homogeneity of the universe is discussed. We show that under the Newtonian gravity, translation of co-moving coordinates in a uniformly expanding universe defines a new accelerated frame. A consistency ... More

Quasi-isotropic cycles and non-singular bounces in a Mixmaster cosmologyFeb 18 2019A Bianchi IX Mixmaster spacetime is the most general spatially homogeneous solution of Einstein's equations and it can represent the space-averaged Universe. We introduce two novel mechanisms resulting in a Mixmaster Universe with non-singular bounces ... More

Dark Cosmology: Investigating Dark Matter & Exotic Physics in the Dark Ages using the Redshifted 21-cm Global SpectrumFeb 16 2019The Dark Ages, probed by the redshifted 21-cm signal, is the ideal epoch for a new rigorous test of the standard LCDM cosmological model. Divergences from that model would indicate new physics, such as dark matter decay (heating) or baryonic cooling beyond ... More

From Dark Matter to Galaxies with Convolutional NetworksFeb 15 2019Cosmological surveys aim at answering fundamental questions about our Universe, including the nature of dark matter or the reason of unexpected accelerated expansion of the Universe. In order to answer these questions, two important ingredients are needed: ... More

Multiplicity functions of quasars: Predictions from the MassiveBlackII simulationFeb 15 2019We examine simulated AGN systems (triples and quadruples, in particular) in the MassiveBlackII simulation. We identify AGN systems (with bolometric luminosity $L_{\mathrm{bol}}>10^{42}~\mathrm{ergs/sec}$) at different scales (defined by the maximum distance ... More

Simulations of the polarized radio sky and predictions on the confusion limit in polarization for future radio surveysFeb 15 2019Numerical simulations offer the unique possibility to forecast the results of surveys and targeted observations that will be performed with next generation instruments like the Square Kilometre Array. In this paper, we investigate for the first time how ... More

A Robust and Efficient Deep Learning Method for Dynamical Mass Measurements of Galaxy ClustersFeb 15 2019We demonstrate the ability of Convolutional Neural Networks (CNNs) to mitigate systematics in the virial scaling relation and produce dynamical mass estimates of galaxy clusters with remarkably low bias and scatter. We present two models, CNN$_\text{1D}$ ... More

The Axidental UniverseFeb 15 2019Theories with several hundred axion fields have enormous numbers of distinct meta-stable minima. A small fraction of these local minima have vacuum energy compatible with current measurements of dark energy. The potential also contains regions suitable ... More

Coset CosmologyFeb 15 2019We show that the potential of Nambu-Goldstone bosons can have two or more local minima e.g. at antipodal positions in the vacuum manifold. This happens in many models of composite Higgs and of composite Dark Matter. Trigonometric potentials lead to unusual ... More

Viable inflationary magnetogenesis with helical couplingFeb 15 2019We consider helical coupling to electromagnetism and present a simple model of evolution of the coupling function leading to a viable inflationary magnetogenesis. In this scenario, helical magnetic fields of any desirable strength of order up to $10^{- ... More

Anisotropic $2$-form dark energyFeb 15 2019We study the dynamics of dark energy in the presence of a 2-form field coupled to a canonical scalar field $\phi$. We consider the coupling proportional to $e^{-\mu \phi/M_{\rm pl}} H_{\alpha \beta \gamma}H^{\alpha \beta \gamma}$ and the scalar potential ... More

Constraining Single Dark Matter Particle Mass by Primordial Gravitational WaveFeb 15 2019We report on a new relation between dark matter (DM) particle mass, $m_\chi$, and the tensor-to-scalar ratio of cosmic microwave background (CMB) anisotropies, $r$. Once $r$ is determined in a future search of primordial gravitational wave (PGW), $m_\chi$ ... More

First Results from the TNG50 Simulation: Galactic outflows driven by supernovae and black hole feedbackFeb 14 2019We present the new TNG50 cosmological, magnetohydrodynamical simulation -- the third and final volume of the IllustrisTNG project. This simulation occupies a unique combination of large volume and high resolution, with a 50 Mpc box sampled by 2160^3 gas ... More

Orientation effects on the near-infrared broad band emission of quasarsFeb 14 2019We recently proposed the equivalent width (EW) of the narrow [OIII]5007{\AA} emission line as an orientation indicator for active galactic nuclei. We tested this method on about $12,300$ optically selected broad line quasars from the SDSS 7th Data Release ... More

On structure formation from a small-scales-interacting dark sectorFeb 14 2019We consider a cosmological model with an interaction between dark matter and dark energy which leaves the background cosmology unaffected and only affects the evolution of the perturbations. This is achieved by introducing a coupling given in terms of ... More

Searching for Highly Magnified Stars at Cosmological Distances: Discovery of a Redshift 0.94 Blue Supergiant in Archival Images of the Galaxy Cluster MACS J0416.1-2403Feb 14 2019Individual highly magnified stars have been recently discovered at lookback times of more than half the age of the Universe, in lensed galaxies that straddle the critical curves of massive galaxy clusters. Having confirmed their detectability, it is now ... More

Neutrino Physics with the PTOLEMY projectFeb 14 2019The PTOLEMY project aims to develop a scalable design for a Cosmic Neutrino Background (CNB) detector, the first of its kind and the only one conceived that can look directly at the image of the Universe encoded in neutrino background produced in the ... More

A semi-analytical perspective on massive galaxies at $z\sim0.55$Feb 14 2019The most massive and luminous galaxies in the Universe serve as powerful probes to study the formation of structure, the assembly of mass, and cosmology. However, their detailed formation and evolution is still barely understood. Here we extract a sample ... More

Galaxy Evolution in ClustersFeb 14 2019In this thesis, we aim to further elucidate the phenomenon of galaxy evolution in the environment of galaxy clusters using the methodology of numerical simulations. For that, we have developed hydrodynamic models in which idealized gas-rich galaxies move ... More

Cosmic Inflation: Trick or Treat?Feb 14 2019Discovered almost forty years ago, inflation has become the leading paradigm for the early universe. Originally invented to avoid the fine-tuning puzzles of the standard model of cosmology, the so-called hot Big Bang phase, inflation has always been the ... More

Discovery of Strongly-lensed Gravitational Waves - Implications for the LSST Observing StrategyFeb 13 2019LSST's wide-field of view and sensitivity will revolutionize studies of the transient sky by finding extraordinary numbers of new transients every night. The recent discovery of a kilonova counterpart to LIGO/Virgo's first detection of gravitational waves ... More

Hunting for the Dark Matter Wake Induced by the Large Magellanic CloudFeb 13 2019Satellite galaxies are predicted to generate gravitational density wakes as they orbit within the dark matter (DM) halos of their hosts, causing their orbits to decay over time. The recent infall of the Milky Way's (MW) most massive satellite galaxy, ... More

$R_h=ct$ and the eternal coasting cosmological modelFeb 13 2019We point out that the nonempty $R_h=ct$ cosmological model has some known antecedents in the literature. Some of those eternal coasting models are published even before the discovery of the accelerated expansion of the universe and were shown to have ... More

Modelling the observed luminosity function and clustering evolution of Lyman-$α$ emitters: growing evidence for late reionizationFeb 13 2019We model the high redshift (z > 5) Lyman-$\alpha$ emitting (LAE) galaxy population using the empirical rest-frame equivalent width distribution. We calibrate to the observed luminosity function and angular correlation function at z = 5.7 as measured by ... More

Revisiting the Dark Photon Explanation of the Muon g-2 AnomalyFeb 13 2019A massive $U(1)^{\prime}$ gauge boson, "dark photon" or $A^{\prime}$, has long been proposed as a potential explanation of the muon $g-2$ anomaly ($g_{\mu} - 2$). However, recent experimental results have excluded this possibility for a dark photon exhibiting ... More

Squeezed tensor non-Gaussianity in non-attractor inflationFeb 13 2019We investigate primordial tensor non-Gaussianity in single field inflation, during a phase of non-attractor evolution when the spectrum of primordial tensor modes can be enhanced to a level detectable at interferometer scales. Making use of a tensor duality ... More

Effective field theory for gravitational radiation in scalar-tensor gravityFeb 13 2019A light scalar degree of freedom, as the one possibly responsible for the accelerated expansion of the Universe, could leave observable traces in the inspiral gravitational wave signal of binary systems. In order to study these effects, we extend the ... More

Two-mediator dark matter models and cosmic electron excessFeb 13 2019The cosmic electron energy spectrum recently observed by the DAMPE experiment exhibits two interesting features, including a break around 0.9 TeV and a sharp resonance near 1.4 TeV. In this analysis, we propose a dark matter explanation to both exotic ... More

Estimating the Integrated Bispectrum from Weak Lensing MapsFeb 13 2019We use a recently introduced statistic called Integrated Bispectrum (IB) to probe the gravity-induced non-Gaussianity at the level of the bispectrum from weak lensing convergence or $\kappa$ maps. We generalize the concept of the IB to spherical coordinates, ... More

Results from the SuperModel Analysis of the X-COP Galaxy Clusters SampleFeb 13 2019In this work, the analysis of the stacked projected temperature profile of twelve galaxy clusters of the X-COP sample is performed via the SuperModel, a tool for investigating the intracluster medium thermodynamic properties already tested on many clusters ... More

Modular Inflation at Higher Level $N$Feb 12 2019We introduce the framework of modular inflation with level structure, generalizing the level one theory considered previously to higher levels. We analyze the modular structure of CMB observables in this framework and show that the nontrivial geometry ... More

Cosmic voids uncovered -- first-order statistics of depressions in the biased density fieldFeb 12 2019Cosmic voids are the major volume component in the matter distribution of the Universe. They posses great potential for constraining dark energy as well as for testing theories of gravity. Nevertheless, in spite of their growing popularity as cosmological ... More

An alternative way to locally measure the Hubble constant using Gravitational Waves and PTAFeb 12 2019Recent research show that the cosmological components of the Universe should influence on the propagation and observation of Gravitational Waves. Furthermore, it has been proposed a new way to measure the cosmological constant using Pulsar Timing Arrays ... More

Mirror magnetic field and its impact on dark matter distribution in galaxiesFeb 12 2019We obtain the value of the mirror magnetic field during different stages of cosmological evolution. We consider the magnetic field generation in the radiation-dominated era and the post-recombination epoch. We also estimate its galactic low-scale value ... More

Scale-invariant in inflation with 1-loop quantum correctionsFeb 12 2019We study quantum corrections to an inflationary model, which has the attractive feature of being classically scale-invariant. In this model, quadratic gravity plays along a scalar field in such a way that inflation begins near the unstable point of the ... More

Scale-invariant inflation with 1-loop quantum correctionsFeb 12 2019Feb 13 2019We study quantum corrections to an inflationary model, which has the attractive feature of being classically scale-invariant. In this model, quadratic gravity plays along a scalar field in such a way that inflation begins near the unstable point of the ... More

Science with TianQin: Preliminary Results on Massive Black Hole BinariesFeb 12 2019We investigate the prospects of detecting gravitational waves from coalescing massive black hole binaries in the Universe with the TianQin observatory, a space-based gravitational wave interferometer proposed to be launched in the 2030s. To frame the ... More

Constraints on axionlike dark matter with masses down to $10^{-23}$ eV/c$^2$Feb 12 2019We analyzed an 6.7-year span of data from a rotating torsion-pendulum containing $\approx 10^{23}$ polarized electrons to search for the "wind" arising from ultralight, axionlike dark matter with masses between $10^{-23}$ and $10^{-18}$ eV/c$^2$. Over ... More

Primordial Black Holes and Co-Decaying Dark MatterFeb 11 2019Models of Co-Decaying dark matter lead to an early matter dominated epoch -- prior to BBN -- which results in an enhancement of the growth of dark matter substructure. If these primordial structures collapse further they can form primordial black holes ... More

Search for dark matter with a 231-day exposure of liquid argon using DEAP-3600 at SNOLABFeb 11 2019DEAP-3600 is a single-phase liquid argon (LAr) direct-detection dark matter experiment, operating 2 km underground at SNOLAB (Sudbury, Canada). The detector consists of 3279 kg of LAr contained in a spherical acrylic vessel. This paper reports on the ... More

Dark Matter Search Results from the Complete Exposure of the PICO-60 C$_3$F$_8$ Bubble ChamberFeb 11 2019Final results are reported from operation of the PICO-60 C$_3$F$_8$ dark matter detector, a bubble chamber filled with 52 kg of C$_3$F$_8$ located in the SNOLAB underground laboratory. The chamber was operated at thermodynamic thresholds as low as 1.2 ... More

Quantifying tension: interpreting the DES evidence ratioFeb 11 2019We provide a new interpretation for the Bayes factor combination used in the DES first year analysis to quantify the tension between the Dark Energy Survey (DES) and Planck datasets. The ratio quantifies a Bayesian confidence in our ability to combine ... More

Inflation after Planck: Judgment DayFeb 11 2019Inflation is considered as the best theory of the early universe by a very large fraction of cosmologists. However, the validity of a scientific model is not decided by counting the number of its supporters and, therefore, this dominance cannot be taken ... More

Horndeski in the SwamplandFeb 11 2019We investigate the implications of string Swampland criteria for alternative theories of gravity. Even though this has not rigorously been proven, there is some evidence that exact de-Sitter solutions with a positive cosmological constant cannot be successfully ... More

The Degree of Fine-Tuning in our Universe -- and OthersFeb 11 2019(abridged) Both fundamental constants that describe the laws of physics and cosmological parameters that determine the cosmic properties must fall within a range of values in order for the universe to develop astrophysical structures and ultimately support ... More

A universal constant for dark matter-baryon interplayFeb 11 2019Recent studies point out that there exists some rough scaling relations for dark matter and some tight connections between dark matter and baryons. However, most of the relations and tight connections can only be found in galaxies, but not in galaxy clusters. ... More

Should $N$-body integrators be symplectic everywhere in phase space?Feb 10 2019Symplectic integrators are the preferred method of solving conservative $N$-body problems in cosmological, stellar cluster, and planetary system simulations because of their superior error properties and ability to compute orbital stability. Newtonian ... More

$k$-essence $f(R)$ Gravity InflationFeb 10 2019In this work we study a modified version of $f(R)$ gravity in which higher order kinetic terms of a scalar field are added in the action of vacuum $f(R)$ gravity. This type of theory is a type of $k$-essence $f(R)$ gravity, and it belongs to the general ... More

Weak lensing cosmology with convolutional neural networks on noisy dataFeb 10 2019Weak gravitational lensing is one of the most promising cosmological probes of the late universe. Several large ongoing (DES, KiDS, HSC) and planned (LSST, EUCLID, WFIRST) astronomical surveys attempt to collect even deeper and larger scale data on weak ... More

QSOs acting as gravitational lenses: halo mass and projected mass density profile at $z\sim0.7$Feb 10 2019Magnification bias is a gravitational lensing effect that is normally overlooked because it is considered sub-optimal in comparison with the lensing shear. Thanks to the demonstrated optimal characteristics of the sub-millimetre galaxies (SMGs) for lensing ... More

Cosmic Anisotropy and Fast Radio BurstsFeb 10 2019In the recent years, the field of Fast Radio Bursts (FRBs) is thriving and growing rapidly. It is of interest to study cosmology by using FRBs with known redshifts. In the present work, we try to test the possible cosmic anisotropy with the simulated ... More

The Transverse-Traceless Spin-2 Gravitational Wave Cannot Be A Standalone Observable Because It Is AcausalFeb 08 2019We show, through an explicit calculation of the relevant Green's functions, that the transverse-traceless (TT) portion of the gravitational perturbations of Minkowski spacetime and of spatially flat cosmologies with a constant equation-of-state $w$ receive ... More

Milky Way Halo Vibrations and Incommensurate Stream VelocitiesFeb 08 2019Collisionless dark matter galactic halos are expected to exhibit damped oscillations as a result of ongoing late time accretion. An n-body model of the cosmological assembly of a Milky Way-like halo is used to quantify the time dependence of its gravitational ... More

Type Ia Supernovae are Excellent Standard Candles in the Near-InfraredFeb 08 2019We analyze a set of 89 Type Ia supernovae (SN Ia) that have both optical and near-infrared (NIR) photometry to derive distances and construct low redshift ($z < 0.04$) Hubble diagrams. We construct mean light curve (LC) templates using a hierarchical ... More

High Performance Computing for gravitational lens modeling: single vs double precision on GPUs and CPUsFeb 08 2019Strong gravitational lensing is a powerful probe of cosmology and the dark matter distribution. Efficient lensing software is already a necessity to fully use its potential and the performance demands will only increase with the upcoming generation of ... More

Constraining the spin-dependent WIMP-nucleon cross sections with XENON1TFeb 08 2019We report the first experimental results on spin-dependent elastic WIMP-nucleon scattering from the XENON1T dark matter search experiment. The analysis uses the full tonne-year exposure of XENON1T to constrain the spin-dependent proton-only and neutron-only ... More

Hyper non-Gaussianities in inflation with strongly non-geodesic motionFeb 08 2019Several recent proposals to embed inflation into high-energy physics rely on inflationary dynamics characterized by a strongly non-geodesic motion in negatively curved field space. This naturally leads to a transient instability of perturbations on sub-Hubble ... More

Baryon acoustic oscillation, Hubble parameter, and angular size measurement constraints on the Hubble constant, dark energy dynamics, and spatial curvatureFeb 08 2019In this paper we use all available baryon acoustic oscillation and Hubble parameter data to constrain six dark energy cosmological models, both spatially flat and non-flat. These data mildly favor (at 1.3-1.4$\sigma$) closed spatial hypersurfaces in the ... More

Non-sphericity of ultra-light axion dark matter halos in the Galactic dwarf spheroidal galaxiesFeb 08 2019Ultra-light axion (ULA) dark matter is one of the possible solutions to resolve small-scale problems, especially the core-cusp problem. This is because ULA dark matter can create a central soliton core in all dark halos stemmed from the quantum pressure ... More

Some Aspects of the Canonical Analysis of Reuter-Weyer RG Improved Einstein-Hilbert ActionFeb 08 2019A canonical analysis of RG improved action of the Einstein-Hilbert functional is performed. The gravitational and cosmological constants as function of the space-time coordinates are treated as external non-geometrical fields. Dirac's constraint analysis ... More

Impact of photometric redshifts on the galaxy power spectrum and BAO scale in the LSST surveyFeb 08 2019Imaging billions of galaxies every few nights during ten years, LSST should be a major contributor to precision cosmology in the 2020 decade. High precision photometric data will be available in six bands, from near-infrared to near-ultraviolet. The computation ... More

Role of intracluster supernovae in radio mini-halos in galaxy clustersFeb 08 2019A possibility of generating a population of cosmic-ray particles accelerated in supernovae typeIa (SNIa) remnants in the intracluster medium (ICM) is discussed. The presently constrained host-less SNIa rates in the clusters are found to be sufficient ... More

Constraining DHOST theories with linear growth of matter density fluctuationsFeb 08 2019We investigate the potential of cosmological observations, such as galaxy surveys, for constraining degenerate higher-order scalar-tensor (DHOST) theories, focusing in particular on the linear growth of the matter density fluctuations. We develop a formalism ... More

Impact of inhomogeneous reionization on the Lyman-α forestFeb 08 2019The Lyman-${\alpha}$ forest at high redshifts is a powerful probe of reionization. Modeling and observing this imprint comes with significant technical challenges: the memory fades away swiftly, hence one must focus on high redshifts. In addition, inhomogeneous ... More

CO luminosity-Linewidth correlation of low and high redshift galaxies and its possible cosmological utilizationFeb 07 2019Feb 11 2019A linear correlation has been proposed between the CO luminosity ($\rm{L}^{\prime}_{\rm{CO}}$) and full-width at half maximum (FWHM) for high-redshift (z > 1) submillimeter galaxies. However, the controversy concerning the $\rm{L}^{\prime}_{\rm{CO}}$-FWHM ... More

CO luminosity-Linewidth correlation of low and high redshift galaxies and its possible cosmological utilizationFeb 07 2019A linear correlation has been proposed between the CO luminosity ($\rm{L}^{\prime}_{\rm{CO}}$) and full-width at half maximum (FWHM) for high-redshift (z > 1) submillimeter galaxies. However, the controversy concerning the $\rm{L}^{\prime}_{\rm{CO}}$-FWHM ... More

Infrared luminosity functions based on 18 mid-infrared bands: revealing cosmic star formation history with AKARI and Hyper Suprime-CamFeb 07 2019Much of the star formation is obscured by dust. For the complete understanding of the cosmic star formation history (CSFH), infrared (IR) census is indispensable. AKARI carried out deep mid-infrared observations using its continuous 9-band filters in ... More

Does AGN Fraction Depend on Redshift or Luminosity? An Extinction-Free Test by 18-band Mid-infrared SED Fitting in the AKARI NEP Wide FieldFeb 07 2019Revealing what fraction of galaxies harbor AGN is central in understanding black hole accretion history of the Universe. However, optical and soft X-ray surveys miss the most highly obscured AGNs. Infrared (IR), instead, is more robust against absorption. ... More

Conditions for Reionizing the Universe with A Low Galaxy Ionizing Photon Escape FractionFeb 07 2019We explore scenarios for reionizing the intergalactic medium with low galaxy ionizing photon escape fractions. We combine simulation-based halo-mass dependent escape fractions with an extrapolation of the observed galaxy rest-ultraviolet luminosity functions ... More

Magnetic field production at a first-order electroweak phase transitionFeb 07 2019We study the generation of magnetic field seeds during a first-order electroweak phase transition, by numerically evolving the classical equations of motion of the bosonic electroweak theory on the lattice. The onset of the transition is implemented by ... More

Fundamental physics constraints from testing the stability of the fine-structure constant with the ELTsFeb 07 2019The increased collecting area of the ELTs will bring fainter high-z targets within the reach of high-resolution ultra-stable spectrographs, thus enabling a new generation of precision consistency tests, including tests of the stability of nature's fundamental ... More

Constraints on millicharged dark matter and axion-like particles from timing of radio wavesFeb 07 2019We derive novel constraints on millicharged dark matter and ultralight axion-like particles (that may or may not be part of the dark matter sector) using pulsar timing and fast radio burst observations. Millicharged dark matter affects the dispersion ... More

Constraints on millicharged dark matter and axion-like particles from timing of radio wavesFeb 07 2019Feb 14 2019We derive novel constraints on millicharged dark matter and ultralight axion-like particles using pulsar timing and fast radio burst observations. Millicharged dark matter affects the dispersion measure of the time of arrival of radio pulses in a way ... More

Prediction of galaxy halo masses in SDSS DR7 via a machine learning approachFeb 07 2019We present a machine learning (ML) approach for the prediction of galaxies' dark matter halo masses that achieves an improved performance over conventional methods. We train three ML algorithms (\texttt{XGBoost}, Random Forests, and neural network) to ... More

Radiative Axion InflationFeb 07 2019Planck data robustly exclude the simple $\lambda\phi^4$ scenario for inflation. This is also the case for models of Axion Inflation in which the inflaton field is the radial part of the Peccei-Quinn complex scalar field. In this letter we show that for ... More

Probing quantum gravity at low energiesFeb 07 2019Planck stars form when a collapsing shell of matter within a black hole reaches the Planck density, roughly equivalent to the mass being compressed into a volumetric size near that of the proton, and rebounds outwards. These planck stars have been considered ... More

Gravitational Waves in $F(R)$ Gravity: Scalar Waves and the Chameleon MechanismFeb 07 2019We discuss the scalar mode of gravitational waves emerging in the context of $F(R)$ gravity by taking into account the chameleon mechanism. Assuming a toy model with a specific matter distribution to reproduce the environment of detection experiment by ... More

Gravitational Waves in $F(R)$ Gravity: Scalar Waves and the Chameleon MechanismFeb 07 2019Feb 12 2019We discuss the scalar mode of gravitational waves emerging in the context of $F(R)$ gravity by taking into account the chameleon mechanism. Assuming a toy model with a specific matter distribution to reproduce the environment of detection experiment by ... More

Signature of Excess Radio Background in the 21-cm Global Signal and Power SpectrumFeb 07 2019The recent tentative detection by the EDGES Low-Band antenna of the hydrogen 21-cm line from cosmic dawn, if confirmed, is the first ever signature observed from the epoch of primordial star formation. However, the magnitude and the shape of this signal ... More