A5061470538- Galaxies: Formation, Evolution, Phenomena
- Cosmology and Gravitation Theories
- Astronomy and Astrophysical Research
- Radio Astronomy Observations and Technology
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Adaptive optics and wavefront sensing
- Gamma-ray bursts and supernovae
- Pulsars and Gravitational Waves Research
- Dark Matter and Cosmic Phenomena
- Astrophysics and Star Formation Studies
- Solar and Space Plasma Dynamics
- Astronomical Observations and Instrumentation
- Astro and Planetary Science
- CCD and CMOS Imaging Sensors
- Geophysics and Gravity Measurements
- Scientific Research and Discoveries
- Calibration and Measurement Techniques
- Astrophysical Phenomena and Observations
- Remote Sensing in Agriculture
- Computational Physics and Python Applications
- Particle physics theoretical and experimental studies
- Quantum Electrodynamics and Casimir Effect
- Superconducting and THz Device Technology
- Relativity and Gravitational Theory
The Ohio State University
2016-2025
Columbus Center
2022
State Library of Ohio
2019-2021
California Institute of Technology
2008-2019
Argonne National Laboratory
2018
Space Telescope Science Institute
2018
Australian Astronomical Observatory
2018
Laboratoire d’Astrophysique de Marseille
2016
Aix-Marseille Université
2016
Centre National de la Recherche Scientifique
2016
This paper describes the Sixth Data Release of Sloan Digital Sky Survey. With this data release, imaging northern Galactic cap is now complete. The survey contains images and parameters roughly 287 million objects over 9583 deg2, including scans a large range latitudes longitudes. also includes 1.27 spectra stars, galaxies, quasars, blank sky (for subtraction) selected 7425 deg2. release much more stellar spectroscopy than was available in previous releases detailed estimates temperatures,...
This paper describes the Fourth Data Release of Sloan Digital Sky Survey (SDSS), including all survey-quality data taken through 2004 June. The release includes five-band photometric for 180 million objects selected over 6670 deg2 and 673,280 spectra galaxies, quasars, stars from 4783 those imaging using standard SDSS target selection algorithms. These numbers represent a roughly 27% increment Third Release; previous releases are included in present release. also an additional 131,840...
The relationship between galaxies and dark matter can be characterized by the halo mass of central galaxy fraction that are satellites. Here we present observational constraints from SDSS on these quantities as a function r-band luminosity stellar using galaxy-galaxy weak lensing, with total 351,507 lenses. We use masses derived spectroscopy virial gravitational lensing to determine efficiency which baryons in have been converted into stars. find an L* 6x10^{10} M_{sun} is hosted 1.4x10^{12}...
Cosmic shear surveys have great promise as tools for precision cosmology, but can be subject to systematic errors including intrinsic ellipticity correlations of the source galaxies. The alignments are believed small deep surveys, this is based on and lensing distortions being uncorrelated. Here we show that gravitational need not independent: between tidal field cause nearby galaxies correlated with acting more distant We estimate magnitude effect two simple intrinsic-alignment models: one...
At the time of recombination, baryons and photons decoupled sound speed in baryonic fluid dropped from relativistic to thermal velocities hydrogen atoms. This is less than relative dark matter computed via linear perturbation theory, so we infer that there are supersonic coherent flows underlying potential wells created by matter. As a result, advection small-scale perturbations (near Jeans scale) large-scale velocity important for formation first structures. effect involves quadratic term...
Recent work has shown that the local non-Gaussianity parameter fNL induces a scale dependent bias, whose amplitude is growing with scale. Here we first rederive this result within context of peak–background split formalism and show it only depends on assumption universality mass function, assuming halo bias mass. We then use extended Press–Schechter to argue may be violated will depend other properties, such as merging history halos. In particular, in limit recent mergers find effect...
We cross-correlate large scale structure (LSS) observations from a number of surveys with CMB anisotropies WMAP to investigate the Integrated Sachs-Wolfe (ISW) effect as function redshift, covering z~0.1-2.5. Our main goal is go beyond reporting detections towards developing reliable likelihood analysis that allows one determine cosmological constraints ISW observations. With this in mind we spend considerable amount effort determining redshift-dependent bias and redshift distribution...
Abstract The Subaru Prime Focus Spectrograph (PFS) is a massively multiplexed fiber-fed optical and near-infrared three-arm spectrograph (Nfiber = 2400, 380 ≤ λ 1260 nm, 1 $_{.}^{\circ}$3 diameter field of view). Here, we summarize the science cases in terms provisional plans for 300-night survey. We describe to constrain nature dark energy via survey emission line galaxies spanning comoving volume 9.3 h−3 Gpc3 redshift range 0.8 < z 2.4. In each six bins, cosmological distances will...
The GMRT Epoch of Reionization (EoR) experiment is an ongoing effort to measure the power spectrum from neutral hydrogen at high redshift. We have previously reported upper limit (70 mK)^2 wavenumbers k=0.65 h/Mpc using a basic piecewise-linear foreground subtraction. In this paper we explore use singular value decomposition remove foregrounds with fewer assumptions about structure. Using method also quantify, for first time, signal loss due filter and present new spectra adjusted loss,...
Recent studies have shown that the cross-correlation coefficient between galaxies and dark matter is very close to unity on scales outside a few virial radii of galaxy haloes, independent details how populate haloes. This finding makes it possible determine clustering from measurements galaxy–galaxy weak lensing clustering. We present new cosmological parameter constraints based large-scale spectroscopic samples Sloan Digital Sky Survey (SDSS) data release 7. generalize approach Baldauf et...
Several recent studies have shown how to properly calculate the observed clustering of galaxies in a relativistic context, and uncovered corrections Newtonian calculation that become significant on scales near horizon. Here, we retrace these calculations show that, approaching horizon, galaxy power spectrum depends strongly which gauge is assumed relate intrinsic fluctuations density matter perturbations through linear bias relation. Starting from simple physical assumptions, derive...
We present a state-of-the-art primordial recombination code, HYREC, including all the physical effects that have been shown to significantly affect recombination. The computation of helium includes simple analytic treatments hydrogen continuum opacity in He I ${2}^{1}{P}^{o}\ensuremath{-}{1}^{1}S$ line, I] ${2}^{3}{P}^{o}\ensuremath{-}{1}^{1}S$ and treats feedback between these lines within on-the-spot approximation. Hydrogen is computed using effective multilevel atom method, virtually...
As the only dark matter candidate that does not invoke a new particle survives to present day, primordial black holes (PBHs) have drawn increasing attention recently. Up now, various observations strongly constrained most of mass range for PBHs, leaving small windows where PBHs could make up substantial fraction matter. Here we revisit PBH constraints asteroid-mass window, i.e., 3.5× 10−17M⊙ < mPBH 4× 10−12M⊙. We 3 categories constraints. (1) For optical microlensing, analyze finite source...
Observational evidence for escaping exoplanet atmospheres has been obtained a few exoplanets to date. It comes from strong transit signals detected in the ultraviolet, most notably wings of hydrogen Lyα (Lyα) line. However, core line is often heavily affected by interstellar absorption and geocoronal emission, limiting information about atmosphere that can be extracted part spectrum. Transit observations atomic lines are (a) sensitive enough trace rarefied gas planetary wind (b) do not...
The Wide Field Infrared Survey Telescope (WFIRST) is a 2.4m space telescope with 0.281 deg^2 field of view for near-IR imaging and slitless spectroscopy coronagraph designed > 10^8 starlight suppresion. As background information Astro2020 white papers, this article summarizes the current design anticipated performance WFIRST. While WFIRST does not have UV imaging/spectroscopic capabilities Hubble Space Telescope, wide surveys hundreds times more efficient. Some most ambitious multi-cycle...
Gravitational lensing of the cosmic microwave background (CMB) polarization field has been recognized as a potentially valuable probe cosmological density field. We apply likelihood-based techniques to problem CMB and show that if B-mode is mapped, then allow significantly better reconstruction than possible using previous quadratic estimator approach. With this method ultimate limit not set by lensed power spectrum. Second-order corrections are known produce curl component deflection cannot...
The Shear TEsting Programme (STEP) is a collaborative project to improve the accuracy and reliability of weak lensing measurement, in preparation for next generation wide-field surveys. We review sixteen current emerging shear measurement methods common language, assess their performance by running them (blindly) on simulated images that contain known signal. determine features algorithms most successfully recover input parameters. achieve previously unattained discriminatory precision our...
We investigate biases induced by the conversion between observed image shape to shear distortion in current weak lensing analysis methods. Such overall calibration cannot be detected standard tests such as E/B decomposition or with stars. find that non-Gaussianity of point spread function has a significant effect and can lead up 15 per cent error on linear amplitude fluctuations sigma_8 depending method analysis. This could explain some discrepancies seen recent determinations from lensing....
Correlations between intrinsic shear and the density field on large scales, a potentially important contaminant for cosmic surveys, have been robustly detected at low redshifts with bright galaxies in Sloan Digital Sky Survey (SDSS) data. Here we present more detailed characterization of this effect, which can cause anticorrelations gravitational lensing ellipticity (GI correlations). This measurement uses 36 278 luminous red (LRGs) from SDSS spectroscopic sample 0.15 < z 0.35, split by...
Gravity waves (GWs) in the early Universe generate B-type polarization cosmic microwave background (CMB), which can be used as a direct way to measure energy scale of inflation. Gravitational lensing contaminates GW signal by converting dominant E into B polarization. By reconstructing potential from CMB itself one decontaminate mode induced lensing. We present results numerical simulations delensing using quadratic and iterative maximum-likelihood reconstruction methods function detector...
The first UV sources in the universe are expected to have coupled HI spin temperature gas kinetic via scattering Lyman-alpha resonance [the Wouthuysen-Field (WF) effect]. By establishing an different from of CMB, WF effect should allow observations during reionization epoch redshifted 21 cm line. This paper investigates four mechanisms that can affect strength were not previously considered: (1) Photons redshifting into Lyman resonances may excite H atom and result a radiative cascade...
We present results of a measurement the shape density profile galaxy groups and clusters traced by 43 335 Luminous Red Galaxies (LRGs) with spectroscopic redshifts from Sloan Digital Sky Survey (SDSS). The galaxies are selected such that they brightest within cylindrical aperture, split into two luminosity samples, modeled as sum stellar dark matter components. detailed investigation many possible systematic effects could contaminate our signal develop methods to remove them, including...
We investigate the correlation of gravitational lensing cosmic microwave background (CMB) with several tracers large-scale structure, including luminous red galaxies (LRGs), quasars, and radio sources. The field is reconstructed based on CMB maps from Wilkinson Microwave Anisotropy Probe (WMAP) satellite; LRGs quasars are observed by Sloan Digital Sky Survey (SDSS); sources in NRAO VLA (NVSS). Combining all three structure samples, we find evidence for a positive cross at...
We perform a statistical weak lensing analysis of dark matter profiles around tracers halo mass from galactic- to cluster-size halos. In this we use 170,640 isolated ~L* galaxies split into ellipticals and spirals, 38,236 groups traced by spectroscopic Luminous Red Galaxies (LRGs) 13,823 MaxBCG clusters the Sloan Digital Sky Survey (SDSS) covering wide range richness. Together these three samples allow determination density halos over orders magnitude in mass, 10^{12} M_{sun} 10^{15}...