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Improved limits on short-wavelength gravitational waves from the cosmic microwave background: The cosmic microwave background (CMB) is affected by the total radiation density around the time of decoupling. At that epoch, neutrinos comprised a significant fraction of the radiative energy, but there could also be a con...
Future dark energy constraints from measurements of quasar parallax: Gaia, SIM and beyond: (Abridged) A consequence of the Earth's motion with respect to the CMB is that over a 10 year period it will travel a distance of ~800 AU. As first noted by Kardashev in 1986, this baseline can be used to carry out astrometric ...
Implementation of two-field inflation for cosmic linear anisotropy solving system: We outline the modifications in the numerical Boltzmann code Cosmic Linear Anisotropy Solving System (CLASS) in order to include extra inflationary fields. The functioning of the code is first described, how and where modifications are...
A giant radio halo in the low luminosity X-ray cluster Abell 523: Radio halos are extended and diffuse non-thermal radio sources present at the cluster center, not obviously associated with any individual galaxy. A strong correlation has been found between the cluster X-ray luminosity and the halo radio power. We obser...
Nonlinear Behavior of Baryon Acoustic Oscillations in Redshift Space from the Zel'dovich Approximation: Baryon acoustic oscillations (BAO) are a powerful probe of the expansion history of the universe, which can tell us about the nature of dark energy. In order to accurately characterize the dark energy equation of s...
Early-type galaxies at z = 1.3. I. The Lynx supercluster: cluster and groups at z=1.3. Morphology and color-magnitude relation: We confirm the detection of 3 groups in the Lynx supercluster, at z~1.3, and give their redshifts and masses. We study the properties of the group galaxies as compared to the central cluster...
Elementary Theorems Regarding Blue Isocurvature Perturbations: Blue CDM-photon isocurvature perturbations are attractive in terms of observability and may be typical from the perspective of generic mass relations in supergravity. We present and apply three theorems useful for blue isocurvature perturbations arising fro...
New measurements of $E_G$: Testing General Relativity with the Weyl potential and galaxy velocities: We combine measurements of galaxy velocities from galaxy surveys with measurements of the Weyl potential from the Dark Energy Survey to test the consistency of General Relativity at cosmological scales. Taking the rat...
Extragalactic large-scale structures in the northern Zone of Avoidance: We used the Nan\c{c}ay Radio Telescope (NRT) to measure the 21 cm line emission of near-infrared bright galaxies in the northern Zone of Avoidance (ZoA) without previous redshift determinations. We selected galaxies with extinction-corrected magnit...
A complete sample of 21-cm absorbers at z~1.3: Giant Metrewave Radio Telescope Survey Using MgII Systems: We present the results of a systematic Giant Metrewave Radio Telescope (GMRT) survey of 21-cm absorption in a representative and unbiased sample of 35 strong MgII systems in the redshift range: zabs~1.10-1.45, 33...
Minkowski Tensors in Three Dimensions - Probing the Anisotropy Generated by Redshift Space Distortion: We apply the Minkowski tensor statistics to three dimensional Gaussian random fields. Minkowski tensors contain information regarding the orientation and shape of excursion sets, that is not present in the scalar Mi...
Cosmological tests of modified gravity: constraints on $F(R)$ theories from the galaxy clustering ratio: The clustering ratio $\eta$, a large-scale structure observable originally designed to constrain the shape of the power spectrum of matter density fluctuations, is shown to provide a sensitive probe of the nature ...
Rapidly Descending Dark Energy and the End of Cosmic Expansion: If dark energy is a form of quintessence driven by a scalar field $\phi$ evolving down a monotonically decreasing potential $V(\phi)$ that passes sufficiently below zero, the universe is destined to undergo a series of smooth transitions. The currently obs...
Ultraluminous Star-Forming Galaxies and Extremely Luminous Warm Molecular Hydrogen Emission at z=2.16 in the PKS 1138-26 Radio Galaxy Protocluster: A deep Spitzer Infrared Spectrograph map of the PKS 1138-26 galaxy protocluster reveals ultraluminous PAH emission from obscured star formation in three protocluster ga...
Uncovering dark matter density profiles in dwarf galaxies with graph neural networks: Dwarf galaxies are small, dark matter-dominated galaxies, some of which are embedded within the Milky Way. Their lack of baryonic matter (e.g., stars and gas) makes them perfect test beds for probing the properties of dark matter --...
Finding the First Cosmic Explosions II: Core-Collapse Supernovae: Understanding the properties of Pop III stars is prerequisite to elucidating the nature of primeval galaxies, the chemical enrichment and reionization of the early IGM, and the origin of supermassive black holes. While the primordial IMF remains unknown,...
Inflationary dynamics of kinetically-coupled gauge fields: We investigate the inflationary dynamics of two kinetically-coupled massless $U(1)$ gauge fields with time-varying kinetic-term coefficients. Ensuring that the system does not have strongly coupled regimes shrinks the parameter space. Also, we further restrict ...
The impact of signal-to-noise, redshift, and angular range on the bias of weak lensing 2-point functions: Weak lensing data follow a naturally skewed distribution, implying the data vector most likely yielded from a survey will systematically fall below its mean. Although this effect is qualitatively known from CMB-a...
A New Method to Measure the Post-Reionization Ionizing Background from the Joint Distribution of Lyman-$α$ and Lyman-$β$ Forest Transmission: The amplitude of the ionizing background that pervades the intergalactic medium (IGM) at the end of the epoch of reionization provides a valuable constraint on the emissivity...
Subhalo accretion through filaments: We track subhalo orbits of galaxy and group sized halos in cosmological simulations. We identify filamentary structures around halos and we use these to define a sample of subhalos accreted from filaments as well as a control sample of subhalos accreted from other directions. We use...
Recovering Redshift Distributions with Cross-Correlations: Pushing The Boundaries: Determining accurate redshift distributions for very large samples of objects has become increasingly important in cosmology. We investigate the impact of extending cross-correlation based redshift distribution recovery methods to incl...
The velocity function in the local environment from LCDM and LWDM constrained simulations: Using constrained simulations of the local Universe for generic cold dark matter and for 1keV warm dark matter, we investigate the difference in the abundance of dark matter halos in the local environment. We find that the mass...
One needs positive signatures for detection of Dark Matter: One believes there is huge amount of Dark Matter particles in our Galaxy which manifest themselves only gravitationally. There is a big challenge to prove their existence in a laboratory experiment. To this end it is not sufficient to fight only for the best e...
The Integrated Sachs Wolfe effect: unWISE and Planck constraints on Dynamical Dark Energy: CMB photons redshift and blueshift as they move through gravitational potentials $\Phi$ while propagating across the Universe. If the potential is not constant in time, the photons will pick up a net redshift or blueshift, know...
AMICO galaxy clusters in KiDS-DR3: cosmological constraints from large-scale stacked weak lensing profiles: Context. The large-scale mass distribution around dark matter haloes hosting galaxy clusters provides sensitive cosmological information. Aims. In this work, we make use of a large photometric galaxy cluster sa...
Modified gravitational collapse, or the wonders of the MOND: There are many hot discussions in the literature about two competing paradigms in galactic and extra-galactic astronomy and cosmology, namely the Dark Matter and the Modified Newtonian Dynamics (MOND). It is very difficult to challenge MOND from the cosmologi...
Hyper Suprime-Cam Year 3 Results: Cosmology from Galaxy Clustering and Weak Lensing with HSC and SDSS using the Minimal Bias Model: We present cosmological parameter constraints from a blind joint analysis of three two-point correlation functions measured from the Year 3 Hyper Suprime-Cam (HSC-Y3) imaging data, cover...
Environments of Strong / Ultrastrong, Ultraviolet Fe II Emitting Quasars: We have investigated the strength of ultraviolet Fe II emission from quasars within the environments of Large Quasar Groups (LQGs) in comparison with quasars elsewhere, for 1.1 <= <z_LQG> <= 1.7, using the DR7QSO catalogue of the Sloan Digital Sk...
A model-independent fit to Planck and BICEP2 data: Inflation is the leading theory to describe elegantly the initial conditions that led to structure formation in our universe. In this paper, we present a novel phenomenological fit to the Planck, WMAP polarisation (WP) and the BICEP2 datasets using an alternative param...
Is the Jeffreys' scale a reliable tool for Bayesian model comparison in cosmology?: We are entering an era where progress in cosmology is driven by data, and alternative models will have to be compared and ruled out according to some consistent criterium. The most conservative and widely used approach is Bayesian mod...
Massive black hole binaries: dynamical evolution and observational signatures: The study of the dynamical evolution of massive black hole pairs in mergers is crucial in the context of a hierarchical galaxy formation scenario. The timescales for the formation and the coalescence of black hole binaries are still poorly...
Effect of Fourier filters in removing periodic systematic effects from CMB data: We consider the application of high-pass Fourier filters to remove periodic systematic fluctuations from full-sky survey CMB datasets. We compare the filter performance with destriping codes commonly used to remove the effect of residual...
A larger value for $H_0$ by an evolving gravitational constant: We provide further evidence that a massless cosmological scalar field with a non-minimal coupling to the Ricci curvature of the type $M^2_{\rm pl}(1+\xi \sigma^n/M_{\rm pl}^n) $ alleviates the existing tension between local measurements of the Hubble const...
LoCuSS: the connection between brightest cluster galaxy activity, gas cooling and dynamical disturbance of X-ray cluster cores: We study the distribution of projected offsets between the cluster X-ray centroid and the brightest cluster galaxy (BCG) for 65 X-ray selected clusters from the Local Cluster Substructure Su...
Scale-dependent bias from an inflationary bispectrum: the effect of a stochastic moving barrier: With the advent of large scale galaxy surveys, constraints on primordial non-Gaussianity (PNG) are expected to reach ${\cal O}(f_\text{NL}) \sim 1$. In order to fully exploit the potential of these future surveys, a deep ...
Testing Emergent Gravity on Galaxy Cluster Scales: Verlinde's theory of Emergent Gravity (EG) describes gravity as an emergent phenomenon rather than a fundamental force. Applying this reasoning in de Sitter space leads to gravity behaving differently on galaxy and galaxy cluster scales; this excess gravity might offer...
Stellar populations of seven early-type dwarf galaxies and their nuclei: Dwarf galaxies are the numerically dominating population in the dense regions of the universe. Although they seem to be simple systems at first view, the stellar populations of dwarf elliptical galaxies (dEs) might be fairly complex. Nucleated dEs...
Dependence of peculiar velocity on the host properties of the gravitational wave sources and its impact on the measurement of Hubble constant: Accurate measurement of the Hubble constant from standard sirens such as the gravitational wave (GW) sources with electromagnetic counterparts relies on the robust peculiar ...
Reconstruction of the primordial power spectra with Planck and BICEP2: By using the cubic spline interpolation method, we reconstruct the shape of the primordial scalar and tensor power spectra from the recently released {\it Planck} temperature and BICEP2 polarization cosmic microwave background data. We find that the...
Effects Of The Ionosphere On Ground-Based Detection Of The Global 21 CM Signal From The Cosmic Dawn And The Dark Ages: Detection of the global HI 21 cm signal from Cosmic Dawn and Epoch of Reionization is the key science driver for several ongoing ground-based and future ground/space-based experiments. The crucial sp...
Gas expulsion by quasar-driven winds as a solution to the over-cooling problem in galaxy groups and clusters: Galaxy groups are not scaled down versions of massive galaxy clusters - the hot gas in groups (known as the intragroup medium, IGrM for short) is, on average, less dense than the intracluster medium, implying...
BeyondPlanck IV. On end-to-end simulations in CMB analysis -- Bayesian versus frequentist statistics: End-to-end simulations play a key role in the analysis of any high-sensitivity CMB experiment, providing high-fidelity systematic error propagation capabilities unmatched by any other means. In this paper, we address...
Eulerian BAO Reconstructions and N-Point Statistics: As galaxy surveys begin to measure the imprint of baryonic acoustic oscillations (BAO) on large-scale structure at the sub-percent level, reconstruction techniques that reduce the contamination from nonlinear clustering become increasingly important. Inverting the no...
Reconstructing the Cosmic Velocity and Tidal Fields with Galaxy Groups Selected from the Sloan Digital Sky Survey: [abridge]Cosmic velocity and tidal fields are important for the understanding of the cosmic web and the environments of galaxies, and can also be used to constrain cosmology. In this paper, we reconstruc...
Cosmology with the sub-millimetre galaxies magnification bias: Tomographic Analysis: As in Gonzalez-Nuevo et al. 2017 and Bonavera et al. 2019, the high-z sub-millimetre galaxies can be used as background sample for gravitational lensing studies thanks to their magnification bias. In particular, as in Bonavera et al....
Galaxy clustering using photometric redshifts: We investigate the evolution of the galaxy two point correlation function (CF) over a wide redshift range, 0.2 < z < 3. For the first time the systematic analysis covers the redshifts above 1 - 1.5. The catalogue of ~250000 galaxies with i+ < 25 and known photometric redsh...
On the suspected timing-offset-induced calibration error in the Wilkinson microwave anisotropy probe time-ordered data: In the time-ordered data (TOD) files of the WMAP CMB observations, there is an undocumented timing offset of -25.6 ms between the spacecraft attitude and radio flux density timestamps. If the offset...
Primordial black holes from metric preheating: mass fraction in the excursion-set approach: We calculate the mass distribution of Primordial Black Holes (PBHs) produced during metric preheating. After inflation, the oscillations of the inflaton at the bottom of its potential source a parametric resonant instability f...
Kiloparsec-scale Spatial Offsets in Double-peaked Narrow-line Active Galactic Nuclei. I. Markers for Selection of Compelling Dual Active Galactic Nucleus Candidates: Merger-remnant galaxies with kpc-scale separation dual active galactic nuclei (AGNs) should be widespread as a consequence of galaxy mergers and trigg...
Nuclear Star Clusters - Structure and Stellar Populations: This is an overview of nuclear star cluster observations, covering their structure, stellar populations, kinematics and possible connection to black holes at the centers of galaxies.
Confidence Level Estimator for cosmological model (Research Note): Models of the Universe like the Concordance Model today used to interpret cosmological observations give expectation values for many cosmological observable so accurate that frequently peoples speak of Precision Cosmology. The quoted accuracies however ...
Apparent Superluminality of Lensed Gravitational Waves: We consider gravitational wave (GW) sources with an associated electromagnetic (EM) counterpart, and analyze the time delay between both signals in the presence of lensing. If GWs have wavelengths comparable to the Schwarzschild radius of astrophysical lenses, the...
CMB-S4: Forecasting Constraints on Primordial Gravitational Waves: CMB-S4---the next-generation ground-based cosmic microwave background (CMB) experiment---is set to significantly advance the sensitivity of CMB measurements and enhance our understanding of the origin and evolution of the Universe, from the highest ener...
Exploring short gamma-ray bursts as gravitational-wave standard sirens: Recent observations support the hypothesis that a large fraction of "short-hard" gamma-ray bursts (SHBs) are associated with compact binary inspiral. Since gravitational-wave (GW) measurements of well-localized inspiraling binaries can measure abso...
Decaying neutrinos: The long way to isotropy: We investigate a scenario in which neutrinos are coupled to a pseudoscalar degree of freedom $\ph$ and where decays $\nu_1 \to \nu_2+\ph$ and inverse decays are the responsible mechanism for obtaining equilibrium. In this context we discuss the implication of the invisible ...
The Tilt of Primordial Gravitational Waves Spectra from BICEP2: In this paper we constrain the tilt of the spectra of primordial gravitational waves from Background Imaging of Cosmic Extragalactic Polarization (BICEP2) data only. We find $r=0.21_{-0.10}^{+0.04}$ and $n_t=-0.06_{-0.23}^{+0.25}$ (at $68\%$ C.L.) which im...
A New Insight into the Classification of Type Ia Supernovae: Type Ia Supernovae (SNe Ia) spectra are compared regarding the coefficient of the largest wavelet scale in their decomposition. Two distinct subgroups were identified and their occurrence is discussed in light of use of SNe Ia as cosmological probes. Apart fr...
Multiband gravitational wave cosmology with stellar origin black hole binaries: Massive stellar origin black hole binaries (SBHBs), originating from stars above the pair-instability mass gap, are primary candidates for multiband gravitational wave (GW) observations. Here we study the possibility to use them as effect...
Using Megamaser Disks to Probe Black Hole Accretion: We examine the alignment between H_2O megamaser disks on sub-pc scales with circumnuclear disks and bars on <500 pc scales observed with HST/WFC3. The HST imaging reveals young stars, indicating the presence of gas. The megamaser disks are not well aligned with the c...
Electron-positron plasma in GRBs and in cosmology: Electron-positron plasma is believed to play imporant role both in the early Universe and in sources of Gamma-Ray Bursts (GRBs). We focus on analogy and difference between physical conditions of electron-positron plasma in the early Universe and in sources of GRBs. We ...
Building a control sample for galaxy pairs: Several observational works have attempted to isolate the effects of galaxy interactions by comparing galaxies in pairs with isolated galaxies. However, different authors have proposed different ways to build these so-called control samples (CS). By using mock galaxy catalo...
Primordial Black Holes With Multi-Modal Mass Spectra: A mechanism for generating primordial black-hole mass spectra with many spikes is proposed and investigated. This mechanism relies on the choice of non-Bunch-Davies vacua, these leading to oscillatory features in the inflationary power spectrum. This in turn generat...
An HI Survey of Six Local Group Analogs. II. HI properties of group galaxies: We have conducted an HI 21 cm emission-line survey of six loose groups of galaxies chosen to be analogs to the Local Group. The survey was conducted using the Parkes Multibeam instrument and the Australia Telescope Compact Array (ATCA) over...
The December 2009 gamma-ray flare of 3C 454.3: the multifrequency campaign: During the month of December, 2009 the blazar 3C 454.3 became the brightest gamma-ray source in the sky, reaching a peak flux F ~2000E-8 ph/cm2/s for E > 100 MeV. Starting in November, 2009 intensive multifrequency campaigns monitored the 3C ...
A High Fidelity Sample of Cold Front Clusters from the Chandra Archive: This paper presents a sample of "cold front" clusters selected from the Chandra archive. The clusters are selected based purely on the existence of surface brightness edges in their Chandra images which are modeled as density jumps. A combination o...
A new approach to simulating collisionless dark matter fluids: Recently, we have shown how current cosmological N-body codes already follow the fine grained phase-space information of the dark matter fluid. Using a tetrahedral tesselation of the three-dimensional manifold that describes perfectly cold fluids in six-dim...
Snowmass 2021 CMB-S4 White Paper: This Snowmass 2021 White Paper describes the Cosmic Microwave Background Stage 4 project CMB-S4, which is designed to cross critical thresholds in our understanding of the origin and evolution of the Universe, from the highest energies at the dawn of time through the growth of structur...
First-year Sloan Digital Sky Survey-II (SDSS-II) supernova results: consistency and constraints with other intermediate-redshift datasets: We present an analysis of the luminosity distances of Type Ia Supernovae from the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey in conjunction with other intermediate red...
New- vs. chaotic-inflations: We show that "spiralized" models of new-inflation can be experimentally identified mostly by their positive spectral running in direct contrast with most chaotic-inflation models which have negative runnings typically in the range of $\mathcal{O}(10^{-4}-10^{-3})$.
CO Observations of the Host Galaxy of GRB000418 at z = 1.1: We performed CO(J=2-1) observations of the host galaxy of GRB000418 at z=1.1181 with the Plateau de Bure Interferometer. Previous studies show that the host galaxy has properties similar to those of an ultraluminous infrared galaxy (ULIRG). The star-formation ...
Extreme value statistics of smooth random Gaussian fields: We consider the Gumbel or extreme value statistics describing the distribution function p_G(x_max) of the maximum values of a random field x within patches of fixed size. We present, for smooth Gaussian random fields in two and three dimensions, an analytical e...
Observational scalings testing modified gravity: We consider different observational effects to test modified gravity approach involving the cosmological constant in the common description of the dark matter and the dark energy. We obtain upper limits for the cosmological constant by studying the scaling relations for ...
Constraining Variable High Velocity Winds from Broad Absorption Line Quasars with Multi-Epoch Spectroscopy: Broad absorption line (BAL) quasars probe the high velocity gas ejected by luminous accreting black holes. BAL variability timescales place constraints on the size, location, and dynamics of the emitting and ab...
Using SKA Rotation Measures to Reveal the Mysteries of the Magnetised Universe: We know that magnetic fields are pervasive across all scales in the Universe and over all of cosmic time and yet our understanding of many of the properties of magnetic fields is still limited. We do not yet know when, where or how the fi...
On constraining Cosmology and the Halo Mass Function with Weak Gravitational Lensing: The discrepancy between the weak lensing (WL) and the {\it Planck} measurements of $S_8$ has been a subject of several studies. These studies tend to show that a suppression of the amplitude of the mass power spectrum $P(k)$ at high...
Scrutinizing Early Dark Energy models through CMB lensing: We investigate early dark energy models in the context of the lensing anomaly by considering two different Cosmic Microwave Background (CMB) datasets: a complete Planck, and a second one primarily based on SPTPol and Planck temperature ($l<1000$). We contrast t...
Early radio and X-ray observations of the youngest nearby type Ia supernova PTF11kly (SN 2011fe): On August 24 (UT) the Palomar Transient Factory (PTF) discovered PTF11kly (SN 2011fe), the youngest and most nearby type Ia supernova (SN Ia) in decades. We followed this event up in the radio (centimeter and millimeter ...
On the lack of stellar bars in Coma dwarf galaxies: We present a study of the bar fraction in the Coma cluster galaxies based on a sample of ~190 galaxies selected from the SDSS-DR6 and observed with the Hubble Space Telescope (HST) Advanced Camera for Survey (ACS). The unprecedented resolution of the HST-ACS images al...
Fingerprint of Galactic Loop I on polarized microwave foregrounds: Context: Currently, detection of the primordial gravitational waves by the B-mode of Cosmic Microwave Background (CMB) is primarily limited by our knowledge of the polarized microwave foreground emissions. Thus improvements of the foreground analysis ar...
NN bundle method applied to cosmology: an improvement in computational times: In the last few years, there has been significant progress in the development of machine learning methods tailored to astrophysics and cosmology. Among the various methods that have been developed, there is one that allows to obtain a bundl...
X-ray Groups of Galaxies at 0.5<z<1 in zCOSMOS: Increased AGN Activities in High Redshift Groups: We present a photometric and spectroscopic study of galaxies at 0.5<z<1 as a function of environment based on data from the zCOSMOS survey. There is a fair amount of evidence that galaxy properties depend on mass of grou...
Model-independent determination of $H_0$ and $Ω_{K0}$ from strong lensing and type Ia supernovae: We present the first determination of the Hubble constant $H_0$ from strong lensing time delay data and type Ia supernova luminosity distances that is independent of the cosmological model. We also determine the spatial ...
The role of Dark Matter interaction in galaxy clusters: We consider a toy model to analyze the consequences of dark matter interaction with a dark energy background on the overall rotation of galaxy clusters and the misalignment between their dark matter and baryon distributions when compared to {\Lambda}CDM prediction...
Probing galaxy cluster and intra-cluster gas with luminous red galaxies: We use the cross-correlation between the thermal Sunyaev-Zeldovich (tSZ) signal measured by the Planck satellite and the luminous red galaxy (LRG) samples provided by the SDSS DR7 to study the properties of galaxy cluster and intra-cluster gas. We...
The globular clusters-stellar haloes connection in early type galaxies: This paper explores if, and to what an extent, the stellar populations of early type galaxies can be traced through the colour distribution of their globular cluster systems. The analysis, based on a galaxy sample from the Virgo ACS data, is an ext...
A Pair of Early- and Late-Forming Galaxy Cluster Samples: a Novel Way of Studying Halo Assembly Bias Assisted by a Constrained Simulation: The halo assembly bias, a phenomenon referring to dependencies of the large-scale bias of a dark matter halo other than its mass, is a fundamental property of the standard cosmolo...
Substructure and galaxy formation in the Copernicus Complexio warm dark matter simulations: We use the Copernicus Complexio (COCO) high resolution $N$-body simulations to investigate differences in the properties of small-scale structures in the standard cold dark matter (CDM) model and in a model with a cutoff in th...
Gravitational Waves from Domain Walls in Pulsar Timing Array Datasets: We present a model-independent search for the gravitational wave background from cosmic domain walls (DWs) in the NANOGrav 12.5 years dataset and International PTA Data Release 2. DWs that annihilate at temperatures $\sim 20-50~\text{MeV}$ with tens...
Observational Constraints on Oscillating Dark-Energy Parametrizations: We perform a detailed confrontation of various oscillating dark-energy parame-trizations with the latest sets of observational data. In particular, we use data from Joint Light Curve analysis (JLA) sample from Supernoave Type Ia, Baryon Acoustic Osc...
Non-Gaussianities and Curvature Perturbations from Hybrid Inflation: For the original hybrid inflation as well as the supersymmetric F-term and D-term hybrid models, we calculate the level of non-gaussianities and the power spectrum of curvature perturbations generated during the waterfall, taking into account the cont...
WMAP 9-year CMB estimation using sparsity: Recovering the Cosmic Microwave Background (CMB) from WMAP data requires galactic foreground emissions to be accurately separated out. Most component separation techniques rely on second order statistics such as Internal Linear Combination (ILC) techniques. In this paper, we p...
The Magellanic Quasars Survey. III. Spectroscopic Confirmation of 758 AGNs Behind the Magellanic Clouds: The Magellanic Quasars Survey (MQS) has now increased the number of quasars known behind the Magellanic Clouds by almost an order of magnitude. All survey fields in the Large Magellanic Cloud (LMC) and 70% of thos...
Searching for the shadows of giants: characterising protoclusters with line of sight Lyman-α absorption: We use state of the art hydrodyamical simulations from the Sherwood, EAGLE and Illustris projects to examine the signature of $M_{\rm z=0}\simeq 10^{14}M_{\odot}$ protoclusters observed in Ly-$\alpha$ absorption a...
New measurements of $Ω_m$ from gamma-ray bursts: Context: Data from cosmic microwave background radiation (CMB), baryon acoustic oscillations (BAO), and supernovae Ia (SNe-Ia) support a constant dark energy equation of state with $w_0 \sim -1$. Measuring the evolution of $w$ along the redshift is one of the most demand...
The Scale Factor in the Universe with Dark Energy: Friedmans cosmological equations for the scale factor are analyzed for the Universe containing dark energy. The parameter of the equation of state of the dark energy is treated as an arbitrary constant whose value lies within the interval $w \in [-1.5, -0.5]$, the limi...
Unmodified Gravity: By relaxing the conventional assumption of a purely gravitational interaction between dark energy and dark matter, substantial alterations to the growth of cosmological structure can occur. In this work we focus on the homogeneous transfer of energy from a decaying form of dark energy. We present si...
Photometric Estimates of Redshifts and Distance Moduli for Type Ia Supernovae: Large planned photometric surveys will discover hundreds of thousands of supernovae (SNe), outstripping the resources available for spectroscopic follow-up and necessitating the development of purely photometric methods to exploit these ev...
Hemispherical Power Asymmetry from Scale-Dependent Modulated Reheating: We propose a new model for the hemispherical power asymmetry of the CMB based on modulated reheating. Non-Gaussianity from modulated reheating can be small enough to satisfy the bound from Planck if the dominant modulation of the inflaton decay rat...
Wouthuysen-Field Coupling in the 21 cm Region Around High Redshift Sources: The 21 cm emission and absorption from gaseous halos around the first generation of star depend on the Wouthuysen-Field (W-F) coupling, which relates the spin temperature with the kinetic temperature of hydrogen gas via the resonant scatterin...
Gravitational lens time-delay as a probe of a possible time variation of the fine-structure constant: A new method based on large-scale structure observations is proposed to probe a possible time variation of the fine-structure constant ($\alpha$). Our analyses are based on time-delay of Strong Gravitational Lensing ...
The effect of curvature in thawing models: We study the evolution of spatial curvature for thawing class of dark energy models. We examine the evolution of the equation of state parameter, $w_\phi$, as a function of the scale factor $a$, for the case in which the scalar field $\phi$ evolve in nearly flat scalar potenti...
The X-ray cluster survey with eROSITA: forecasts for cosmology, cluster physics and primordial non-Gaussianity: Starting in late 2013, the eROSITA telescope will survey the X-ray sky with unprecedented sensitivity. Assuming a detection limit of 50 photons in the (0.5-2.0) keV energy band with a typical exposure time ...
Temperature Structure of the Intra-Cluster Medium from SPH and AMR simulations: Analyses of cosmological hydrodynamic simulations of galaxy clusters suggest that X-ray masses can be underestimated by 10% to 30%. The largest bias originates by both violation of hydrostatic equilibrium and an additional temperature bia...
Low-power Radio Galaxies in the Distant Universe: A search for FRI at 1<z<2 in the COSMOS field: We present a search for FRI radio galaxies between 1 < z < 2 in the COSMOS field. In absence of spectroscopic redshift measurements, the selection method is based on multiple steps which make use of both radio and optical...
Testing interacting dark matter and dark energy model with cosmological data: We investigate the model of dark matter-dark energy (DM-DE) interaction with coupling strength proportional to the multiplication of dark sector densities with different power indices $Q = \gamma \rho_{\rm c}^{\alpha} \rho_{\rm d}^{\beta}$....
Particle acceleration and dynamics of double-double radio galaxies: theory vs. observations: In this paper we show that a small sample of radio galaxies with evidence for multiple epochs of jet activity (so-called `double-double' radio galaxies) have the same electron injection spectral index in the two activity epis...
DAMA and the self similar infall halo model: The annual modulation in the rate of WIMP recoils observed by the DAMA collaboration at high significance is often analyzed in the context of an isothermal Maxwell-Boltzmann velocity distribution. While this is the simplest model, there is a need to consider other well motiv...
Sidestepping the inversion of the weak-lensing covariance matrix with Approximate Bayesian Computation: Weak gravitational lensing is one of the few direct methods to map the dark-matter distribution on large scales in the Universe, and to estimate cosmological parameters. We study a Bayesian inference problem where ...
How to make a clean separation between CMB E and B modes with proper foreground masking: We investigate the E/B decomposition of CMB polarization on a masked sky. In real space, operators of E and B mode decomposition involve only differentials of CMB polarization. We may, therefore in principle, perform a clean E/B ...
Simulated differential observations of the Sunyaev-Zel'dovich Effect: Probing the Dark Ages and Epoch of Reionization: This work presents an analytical approach for studying the cosmological 21cm background signal from the Dark Ages (DA) and subsequent Epoch of Reionization (EoR). We simulate differential observation...
Lessons from cosmic history: The case for a linear star formation -- H2 relation: Observations show that star formation in galaxies is closely correlated with the abundance of molecular hydrogen. Modeling this empirical relation from first principles proves challenging, however, and many questions regarding its prope...
Testing self-interacting dark matter with galaxy warps: Self-interacting dark matter (SIDM) is an able alternative to collisionless dark matter. If dark matter does have self-interactions, we would expect this to cause a separation between the collisionless stars and the dark matter halo of a galaxy as it falls through...
Effect of Template Uncertainties on the WMAP and Planck Measures of the Optical Depth Due To Reionization: The reionization optical depth is the most poorly determined of the six $\Lambda$CDM parameters fit to CMB anisotropy data. Instrumental noise and systematics have prevented uncertainties from reaching their cos...
Detection of PAH and Far-Infrared Emission from the Cosmic Eye: Probing the Dust and Star Formation of Lyman Break Galaxies: We report the results of a Spitzer infrared study of the Cosmic Eye, a strongly lensed, L*_UV Lyman Break Galaxy (LBG) at z=3.074. We obtained Spitzer IRS spectroscopy as well as MIPS 24 and 70...
The evolution of quiescent galaxies at high redshift (z > 1.4): We have studied the evolution of high redshift quiescent galaxies over an effective area of ~1.7 deg^2 in the COSMOS field. Galaxies have been divided according to their star-formation activity and the evolution of the different populations has been invest...
High-Velocity Line Forming Regions in the Type Ia Supernova 2009ig: We report measurements and analysis of high-velocity (> 20,000 km/s) and photospheric absorption features in a series of spectra of the Type Ia supernova (SN) 2009ig obtained between -14d and +13d with respect to the time of maximum B-band luminosity. ...
Constraining the average magnetic field in galaxy clusters with current and upcoming CMB surveys: Galaxy clusters that host radio halos indicate the presence of population(s) of non-thermal electrons. These electrons can scatter low-energy photons of the Cosmic Microwave Background, resulting in the non-thermal Sunya...
CMB Lensing Power Spectrum Biases from Galaxies and Clusters using High-angular Resolution Temperature Maps: The lensing power spectrum from cosmic microwave background (CMB) temperature maps will be measured with unprecedented precision with upcoming experiments, including upgrades to ACT and SPT. Achieving signific...
The Websky Extragalactic CMB Simulations: We present a new pipeline for the efficient generation of synthetic observations of the extragalactic microwave sky, tailored to large ground-based CMB experiments such as the Simons Observatory, Advanced ACTPol, SPT-3G, and CMB-S4. Such simulated observations are a key technic...
The morphologies and masses of extremely red galaxies in the Groth Strip survey: We present a new cataloge of EROs from the Groth strip and study the relation between their morphology and mass. We find 102 EROs (F814W-K=>4, K<=21.0), over a survey area of 155 arcmin^2. The photometric data include U,B,F606W,F814W,J,K...
Molecular Chemistry for Dark Matter II: Recombination, Molecule Formation, and Halo Mass Function in Atomic Dark Matter: Dissipative dark matter predicts rich observable phenomena that can be tested with future large-scale structure surveys. As a specific example, we study atomic dark matter, consisting of a heavy pa...
Internal kinematic and physical properties in a BCD galaxy: Haro 15 in detail: We present a detailed study of the kinematic and physical properties of the ionized gas in multiple knots of the blue compact dwarf galaxy Haro 15. Using echelle and long slit spectroscopy data, obtained with different instruments at Las C...
Galaxy disks do not need to survive in the L-CDM paradigm: the galaxy merger rate out to z~1.5 from morpho-kinematic data: About two-thirds of present-day, large galaxies are spirals such as the Milky Way or Andromeda, but the way their thin rotating disks formed remains uncertain. Observations have revealed that hal...
Mid-Infrared Properties of Nearby Luminous Infrared Galaxies I: Spitzer IRS Spectra for the GOALS Sample: The Great Observatories All-Sky LIRG Survey (GOALS) is a multiwavelength study of luminous infrared galaxies (LIRGs) in the local universe. Here we present low resolution Spitzer spectra covering 5-38um and provi...
The Stochastic Gravitational Wave Background Generated by Cosmic String Networks: the Small-Loop Regime: We consider an alternative approach for the computation of the stochastic gravitational wave background generated by small loops produced throughout the cosmological evolution of cosmic string networks and use it ...
Constraints on compact dark matter from lensing of gravitational waves for the third-generation gravitational wave detector: Since the first gravitational wave (GW) event from binary black hole (BBH) was detected by LIGO-Virgo, GWs have become a useful probe on astrophysics and cosmology. If compact dark matter (DM) ...
Gravitational waves and stalled satellites from massive galaxy mergers at z <= 1: We present a model for merger-driven evolution of the mass function for massive galaxies and their central supermassive black holes at late times. We discuss the current observational evidence in favor of merger-driven massive galaxy ev...
Identification of a Complete 160 micron Flux-Limited Sample of Infrared Galaxies in the ISO Lockman Hole 1-Deg^2 Deep Fields: Source Properties and Evidence for Strong Evolution in the FIR Luminosity Function for ULIRGs: We have identified a complete, flux-limited, (S_160>120 mJy), sample of 160 micron-selected sou...
Non-Gaussianity in the HILC foreground-reduced three-year WMAP CMB map: A detection or nondetection of primordial non-Gaussianity in the CMB data is essential not only to test alternative models of the physics of the early universe but also to discriminate among classes of inflationary models. Given this far reaching c...
Enhanced curvature perturbations from spherical domain walls nucleated during inflation: We investigate spherical domain walls~(DWs) nucleated via quantum tunneling in multifield inflationary models and curvature perturbations induced by the inhomogeneous distribution of those DWs. We consider the case that the Eucli...
SZ Science with an ALMA Band 1 Receiver System: We present the first full interferometric simulations of galaxy clusters containing radio plasma bubbles as observed by the proposed band 1 receiver system for the ALMA telescope. We discuss the observational requirements for detecting intracluster substructure directly f...
Gravitational waves and gamma-ray bursts: Gamma-Ray Bursts are likely associated with a catastrophic energy release in stellar mass objects. Electromagnetic observations provide important, but indirect information on the progenitor. On the other hand, gravitational waves emitted from the central source, carry direct in...
Cosmic Evolution of Black Holes and Spheroids. IV. The BH Mass - Spheroid Luminosity Relation: From high-resolution images of 23 Seyfert-1 galaxies at z=0.36 and z=0.57 obtained with the Near Infrared Camera and Multi-Object Spectrometer on board the Hubble Space Telescope (HST), we determine host-galaxy morphology, ...
Constraints on primordial black holes and curvature perturbations from the global 21cm signal: The recent observations of the global 21cm signal by EDGES and gravitational waves by LIGO/VIGO have revived interest in PBHs. Different from previous works, we investigate the influence of PBHs on the evolution of the IGM ...
On the road to percent accuracy VI: the nonlinear power spectrum for interacting dark energy with baryonic feedback and massive neutrinos: Understanding nonlinear structure formation is crucial for fully exploring the data generated by stage IV surveys, requiring accurate modelling of the power spectrum. This is chal...
A multi-frequency study of the SZE in giant radio galaxies: Radio-galaxy (RG) lobes contain relativistic electrons embedded in a tangled magnetic field that produce, in addition to low-frequency synchrotron radio emission, inverse-Compton scattering (ICS) of the cosmic microwave background (CMB) photons. This produces ...
Perturbed recombination from inhomogeneous photon injection and application to accreting primordial black holes: Exotic electromagnetic energy injection in the early Universe may alter cosmological recombination, and ultimately cosmic microwave background (CMB) anisotropies. Moreover, if energy injection is inhomogen...
Self-interactions of ULDM to the rescue?: One of the most important questions in cosmology is concerning the fundamental nature of dark matter (DM). DM could consist of spinless particles of very small mass i.e. $m \sim 10^{-22}\ \text{eV}$. This kind of ultralight dark matter (ULDM) would form cored density profiles (...
Coupling dark-baryonic matter density profile for vacuum decay scenarios: The cosmological consequences of an interacting model in which vacuum decay law is deducted from the effect that vacuum decay has on the dark matter evolution are investigated. Here, the baryonic matter is also considered as a fluid gravitational...
Restoring cosmological concordance with early dark energy and massive neutrinos?: The early dark energy (EDE) solution to the Hubble tension comes at the cost of an increased clustering amplitude that has been argued to worsen the fit to galaxy clustering data. We explore whether freeing the total neutrino mass $M_{\...
Relating the inhomogeneous power spectrum to the CMB hemispherical anisotropy: We relate the observed hemispherical anisotropy in the cosmic microwave radiation data to an inhomogeneous power spectrum model. The hemispherical anisotropy can be parameterized in terms of the dipole modulation model. This model leads to...
Do the Early Galaxies observed by JWST disagree with Planck's CMB polarization measurements?: The recent observations from the James Webb Space Telescope have led to a surprising discovery of a significant density of massive galaxies with masses of $M \ge 10^{10.5} M_{\odot}$ at redshifts of approximately $z\sim 10$....
Exploring local fNL estimators based on the binned bispectrum: We explore different estimators of the local non-linear coupling parameter, fNL, based on the binned bispectrum presented in Bucher et al. Using simulations of Wilkinson Microwave Anisotropy Probe (WMAP)-7yr data, we compare the performance of a regression ...
The SINS/zC-SINF survey of z~2 galaxy kinematics: evidence for gravitational quenching: As part of the SINS/zC-SINF surveys of high-z galaxy kinematics, we derive the radial distributions of H-alpha surface brightness, stellar mass surface density, and dynamical mass at ~2 kpc resolution in 19 z~2 star-forming disks ...
What do we know about cosmography: In the present paper, we investigate the cosmographic problem using the bias-variance trade-off. We find that both the z-redshift and the $y=z/(1+z)$-redshift can present a small bias estimation. It means that the cosmography can describe the supernova data more accurately. Minimizing...
Detection of the Gravitational Lens Magnifying a Type Ia Supernova: Objects of known brightness, like Type Ia supernovae (SNIa), can be used to measure distances. If a massive object warps spacetime to form multiple images of a background SNIa, a direct test of cosmic expansion is also possible. However, these lensing ...
Simulations of the Pairwise Kinematic Sunyaev-Zel'dovich Signal: The pairwise kinematic Sunyaev-Zel'dovich (kSZ) signal from galaxy clusters is a probe of their line-of-sight momenta, and thus a potentially valuable source of cosmological information. In addition to the momenta, the amplitude of the measured signal dep...
First LIGO search for gravitational wave bursts from cosmic (super)strings: We report on a matched-filter search for gravitational wave bursts from cosmic string cusps using LIGO data from the fourth science run (S4) which took place in February and March 2005. No gravitational waves were detected in 14.9 days of dat...
Gas cooling in semi-analytic models and SPH simulations: are results consistent?: We present a detailed comparison between the galaxy populations within a massive cluster, as predicted by hydrodynamical SPH simulations and by a semi-analytic model (SAM) of galaxy formation. Both models include gas cooling and a simpl...
Turbulence and Radio Mini-halos in the Sloshing Cores of Galaxy Clusters: A number of relaxed, cool-core galaxy clusters exhibit diffuse, steep-spectrum radio sources in their central regions, known as radio mini-halos. It has been proposed that the relativistic electrons responsible for the emission have been reaccele...
Primordial perturbations with pre-inflationary bounce: Based on the effective field theory (EFT) of nonsingular cosmologies, we build a stable model, without the ghost and gradient instabilities, of bounce inflation (inflation is preceded by a cosmological bounce). We perform a full simulation for the evolution of scal...
The Evolution of Luminous Compact Blue Galaxies: Disks or Spheroids?: Luminous compact blue galaxies (LCBGs) are a diverse class of galaxies characterized by high luminosity, blue color, and high surface brightness that sit at the critical juncture of galaxies evolving from the blue to the red sequence. As part of our ...
Galaxy Motions, Turbulence and Conduction in Clusters of Galaxies: Unopposed radiative cooling in clusters of galaxies results in excessive mass deposition rates. However, the cool cores of galaxy clusters are continuously heated by thermal conduction and turbulent heat diffusion due to minor mergers or the galaxies or...
The Physics and Physical Properties of Quasar Outflows: We describe two studies designed to characterize the total column densities, kinetic energies, and acceleration physics of broad absorption line (BAL) outflows in quasars. The first study uses new Chandra X-ray and ground-based rest-frame UV observations of 7 quas...
A multi-wavelength strong lensing analysis of baryons and dark matter in the dynamically active cluster AC 114: Strong lensing studies can provide detailed mass maps of the inner regions even in dynamically active galaxy clusters. It is shown that proper modelling of the intracluster medium, i.e. the main baryonic co...
Influence of baryons on the orbital structure of dark matter haloes: We explore the dynamical signatures imprinted by baryons on dark matter haloes during the formation process using the OverWhelmingly Large Simulations (OWLS), a set of state-of-the-art high-resolution cosmological hydrodynamical simulations. We presen...
Clustering and Halo Abundances in Early Dark Energy Cosmological Models: LCDM cosmological models with Early Dark Energy (EDE) have been proposed to resolve tensions between the Hubble constant H0 = 100h km/s/Mpc measured locally, giving h ~ 0.73, and H0 deduced from Planck cosmic microwave background (CMB) and other e...
LiteBIRD Science Goals and Forecasts: Improving Sensitivity to Inflationary Gravitational Waves with Multitracer Delensing: We estimate the efficiency of mitigating the lensing $B$-mode polarization, the so-called delensing, for the $LiteBIRD$ experiment with multiple external data sets of lensing-mass tracers. The c...
Cool Core Bias in Sunyaev-Zel'dovich Galaxy Cluster Surveys: Sunyaev-Zeldovich (SZ) surveys find massive clusters of galaxies by measuring the inverse Compton scattering of cosmic microwave background off of intra-cluster gas. The cluster selection function from such surveys is expected to be nearly independent of reds...
The Relation Between Line Emission and Brightest Cluster Galaxies in Three Exceptional Clusters: Evidence for Gas Cooling from the ICM: There is a strong spatial correlation between brightest cluster galaxies (BCGs) and the peak density and cooling rate of the intra-cluster medium (ICM). In this paper we combine inte...
Nearby Galaxies: Templates for Galaxies Across Cosmic Time: Studies of nearby galaxies including the Milky Way have provided fundamental information on the evolution of structure in the Universe, the existence and nature of dark matter, the origin and evolution of galaxies, and the global features of star formation. Ye...
Features and New Physical Scales in Primordial Observables: Theory and Observation: All cosmological observations to date are consistent with adiabatic, Gaussian and nearly scale invariant initial conditions. These findings provide strong evidence for a particular symmetry breaking pattern in the very early universe ...
A Composite Likelihood Approach for Inference under Photometric Redshift Uncertainty: Obtaining accurately calibrated redshift distributions of photometric samples is one of the great challenges in photometric surveys like LSST, Euclid, HSC, KiDS, and DES. We present an inference methodology that combines the redshif...
Accurate Analytic Model for the Weak Lensing Convergence One-Point Probability Distribution Function and its Auto-Covariance: The one-point probability distribution function (PDF) is a powerful summary statistic for non-Gaussian cosmological fields, such as the weak lensing (WL) convergence reconstructed from galaxy ...
First Structure Formation under the Influence of Gas-Dark Matter Streaming Velocity and Density: Impact of the Baryons-trace-dark matter Approximation: The impact of the streaming between baryons and dark matter on the first structures has been actively explored by recent studies. We investigate how the key results...
A test of galaxy cluster fundamental plane for the X-COP sample: We test the galaxy cluster fundamental plane using the X-COP sample of 12 clusters. The fundamental plane is given by the relation $T_X \propto M_s^{\alpha} r_s^{\beta}$, where $T_X$, $M_s$, and $r_s$ correspond to the gas temperature, NFW halo mass, and ...
Linear Tidal Vestige found in the WM Sheet: We present a vestige of the linear tidal influence on the spin orientations of the constituent galaxies of the WM sheet discovered in the vicinity of the Virgo cluster and the Local Void. The WM sheet is chosen as an optimal target since it has a rectangular parallelepiped-li...
On the road to percent accuracy III: non-linear reaction of the matter power spectrum to massive neutrinos: We analytically model the non-linear effects induced by massive neutrinos on the total matter power spectrum using the halo model reaction framework of Cataneo et al. 2019. In this approach the halo model is us...
Analytical scaling solutions for the evolution of cosmic domain walls in a parameter-free velocity-dependent one-scale model: We derive an analytical approximation for the linear scaling evolution of the characteristic length $L$ and the root-mean-squared velocity $\sigma_v$ of standard frictionless domain wall netwo...
Results of the GREAT08 Challenge: An image analysis competition for cosmological lensing: We present the results of the GREAT08 Challenge, a blind analysis challenge to infer weak gravitational lensing shear distortions from images. The primary goal was to stimulate new ideas by presenting the problem to researchers ...
Modelling the Spoon IRS diagnostic diagram: We explore whether our models for starbursts, quiescent star-forming galaxies and for AGN dust tori are able to model the full range of IRS spectra measured with Spitzer. The diagnostic plot of 9.7 mu silicate optical depth versus 6.2 mu PAH equivalent width, introduced by Sp...
Evidence for dark matter interactions in cosmological precision data?: We study a two-parameter extension of the cosmological standard model $\Lambda$CDM in which cold dark matter interacts with a new form of dark radiation. The two parameters correspond to the energy density in the dark radiation fluid $\Delta N_\math...
Type II Supernovae as Distance Indicators at Near-IR Wavelengths: Motivated by the advantages of observing at near-IR wavelengths, we investigate Type II supernovae (SNe II) as distance indicators at those wavelengths through the Photospheric Magnitude Method (PMM). For the analysis, we use $BVIJH$ photometry and optic...
Modified Gravity and Cosmology: In this review we present a thoroughly comprehensive survey of recent work on modified theories of gravity and their cosmological consequences. Amongst other things, we cover General Relativity, Scalar-Tensor, Einstein-Aether, and Bimetric theories, as well as TeVeS, f(R), general higher...
Cosmological CPT Violation and CMB Polarization Measurements: In this paper we study the possibility of testing Charge-Parity-Time Reversal (CPT) symmetry with cosmic microwave background (CMB) experiments. We consider two kinds of Chern-Simons (CS) term, electromagnetic CS term and gravitational CS term, and study the...
The Lx-Tvir relation in galaxy clusters: Effects of radiative cooling and AGN heating: We present a detailed investigation of the X-ray luminosity (Lx)-gas temperature (Tvir) relation of the complete X-ray flux-limited sample of the 64 brightest galaxy clusters in the sky (HIFLUGCS). We study the influence of two ast...
Nonlocal Gravitational Models and Exact Solutions: A nonlocal gravity model with a function $f(\Box^{-1} R)$, where $\Box$ is the d'Alembert operator, is considered. The algorithm, allowing to reconstruct $f(\Box^{-1} R)$, corresponding to the given Hubble parameter and the state parameter of the matter, is proposed. U...
A New Statistic for Analyzing Baryon Acoustic Oscillations: We introduce a new statistic omega_l for measuring and analyzing large-scale structure and particularly the baryon acoustic oscillations. omega_l is a band-filtered, configuration space statistic that is easily implemented and has advantages over the tradition...
Testing the Distance-Duality Relation with Galaxy Clusters and Type Ia Supernovae: In this letter we propose a new and model-independent cosmological test for the distance-duality (DD) relation, \eta=D_{L}(z)(1+z)^{-2}/D_{A}(z)=1, where D_{L} and D_{A} are, respectively, the luminosity and angular diameter distances....
Gravitational perturbations from oscillons and transients after inflation: We 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 pe...
Dark Matter: I give a review of the development of the concept of dark matter. The dark matter story passed through several stages from a minor observational puzzle to a major challenge for theory of elementary particles. Modern data suggest that dark matter is the dominant matter component in the Universe, and that it...
Testing one-loop galaxy bias: cosmological constraints from the power spectrum: We investigate the impact of different assumptions in the modeling of one-loop galaxy bias on the recovery of cosmological parameters, as a follow up of the analysis done in the first paper of the series at fixed cosmology. We use three d...
Clarifying the Hubble constant tension with a Bayesian hierarchical model of the local distance ladder: Estimates of the Hubble constant, $H_0$, from the distance ladder and the cosmic microwave background (CMB) differ at the $\sim$3-$\sigma$ level, indicating a potential issue with the standard $\Lambda$CDM cosmolog...
Implications of the $z>5$ Lyman-$α$ forest for the 21-cm power spectrum from the epoch of reionization: Our understanding of the intergalactic medium at redshifts $z=5$-$6$ has improved considerably in the last few years due to the discovery of quasars with $z>6$ that enable Lyman-$\alpha$ forest studies at these red...
Resilience of long modes in cosmological observables: By a careful implementation of gauge transformations involving long-wavelength modes, we show that a variety of effects involving squeezed bispectrum configurations, for which one Fourier mode is much shorter than the other two, cannot be gauged away, except for the...
The effect of annealing on the RHESSI gamma-ray detectors: The performance of nine RHESSI germanium detectors has been gradually deteriorating since its launch in 2002 because of radiation damage caused by passing through the Earth's radiation belts. To restore its former sensitivity, the spectrometer underwent an anne...
Primordial power spectrum versus extension parameters beyond the standard model: We reconstruct the shape of the primordial power spectrum of curvature perturbations in extended cosmological models, including addition of massive neutrinos, extra relativistic species or varying primordial helium abundance, from the la...
Inverse Depolarization: A Potential Probe of Internal Faraday Rotation and Helical Magnetic Fields in Extragalactic Radio Jets: Motivated by recent observations that show increasing fractional linear polarization with increasing wavelength in a small number of optically thin jet features, i.e. "inverse depolarization...
A cosmic-ray dominated ISM in Ultra Luminous Infrared Galaxies: new initial conditions for star formation: The high-density star formation typical of the merger/starburst events that power the large IR luminosities of Ultra Luminous Infrared Galaxies (ULIRGs) (L_{IR}>10^{12}Lsol) throughout the Universe results to ...
Relating basic properties of bright early-type dwarf galaxies to their location in Abell 901/902: We present a study of the population of bright early-type dwarf galaxies in the multiple-cluster system Abell 901/902. We use data from the STAGES survey and COMBO-17 to investigate the relation between the color and str...
Cross-correlating Astrophysical and Cosmological Gravitational Wave Backgrounds with the Cosmic Microwave Background: General Relativity provides us with an extremely powerful tool to extract at the same time astrophysical and cosmological information from the Stochastic Gravitational Wave Backgrounds (SGWBs): the cr...
Reionization and Cosmic Dawn: theory and simulations: We highlight recent progress in the sophistication and diversification of cosmic dawn and reionization simulations. The application of these modeling tools to current observations has allowed us narrow down the timing of reionization, which we now know to within dz ...
On the IR-Resummation in the EFTofLSS: We propose a simplification for the IR-resummation scheme of Senatore and Zaldarriaga, and also include its next-to-leading order corrections coming from the tree-level three-point function of the long displacement field. First we show that the new simplified formula shares the sa...
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Luminosity and Color Dependence and Redshift Evolution: We measure the luminosity and color dependence and the redshift evolution of galaxy clustering in the Sloan Digital Sky Survey-III Baryon Oscillation Spectroscopic Survey Ninth D...
Energetic galaxy-wide outflows in high-redshift ultra-luminous infrared galaxies hosting AGN activity: We present integral field spectroscopy observations, covering the [O III]4959,5007 emission-line doublet of eight high-redshift (z=1.4-3.4) ultra-luminous infrared galaxies (ULIRGs) that host Active Galactic Nuclei ...
Molecular Gas in Infrared Ultraluminous QSO Hosts: We report CO detections in 17 out of 19 infrared ultraluminous QSO (IR QSO) hosts observed with the IRAM 30m telescope. The cold molecular gas reservoir in these objects is in a range of 0.2--2.1$\times 10^{10}M_\odot$ (adopting a CO-to-${\rm H_2}$ conversion factor $\...
Dust properties of Lyman break galaxies in cosmological simulations: Recent observations have indicated the existence of dust in high-redshift galaxies, however, the dust properties in them are still unknown. Here we present theoretical constraints on dust properties in Lyman break galaxies (LBGs) at z=3 by post-proces...
Discovery of VHE gamma-rays from Centaurus A: We report the discovery of faint very high energy (VHE, E > 100 GeV) gamma-ray emission from the radio galaxy Centaurus A in deep observations performed with the H.E.S.S. experiment. A signal with a statistical significance of 5.0 sigma is detected from the region including...
Intermediate redshift calibration of Gamma-ray Bursts and cosmic constraints in non-flat cosmology: We propose how to calibrate long gamma-ray burst (GRB) correlations employing intermediate redshift data sets, instead of limiting to $z\simeq0$ catalogs. To do so, we examine the most updated observational Hubble data...
(Lack of) Cosmological evidence for dark radiation after Planck: We use Bayesian model comparison to determine whether extensions to Standard-Model neutrino physics -- primarily additional effective numbers of neutrinos and/or massive neutrinos -- are merited by the latest cosmological data. Given the significant advan...