A5065901451- Radio Astronomy Observations and Technology
- Galaxies: Formation, Evolution, Phenomena
- Cosmology and Gravitation Theories
- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- Astronomy and Astrophysical Research
- Particle physics theoretical and experimental studies
- Stellar, planetary, and galactic studies
- Scientific Research and Discoveries
- Neutrino Physics Research
- Planetary Science and Exploration
- Space Science and Extraterrestrial Life
- Superconducting and THz Device Technology
- Astro and Planetary Science
- Solar and Space Plasma Dynamics
- Climate variability and models
- Astrophysics and Star Formation Studies
- Urological Disorders and Treatments
- Geophysics and Gravity Measurements
- Digital Radiography and Breast Imaging
- Enhanced Oil Recovery Techniques
- Astrophysical Phenomena and Observations
- Traumatic Brain Injury and Neurovascular Disturbances
- Precipitation Measurement and Analysis
- Astronomical Observations and Instrumentation
University of California, Berkeley
2023-2025
Canadian Institute for Theoretical Astrophysics
2022-2024
University of Toronto
2022-2024
Princeton University
2018-2023
University of Manitoba
2021
Queen's University
2017
University of Alberta
2016
National Research Council Canada
2016
Swarthmore College
2014
We present new arcminute-resolution maps of the Cosmic Microwave Background temperature and polarization anisotropy from Atacama Cosmology Telescope, using data taken 2013-2016 at 98 150 GHz. The cover more than 17,000 deg$^2$, deepest 600 deg$^2$ with noise levels below 10 $\mu$K-arcmin. use power spectrum derived almost 6,000 these to constrain cosmology. ACT enable a measurement angular scale features in both divergence-like anisotropy, tracing velocity density last-scattering. From one...
We present the temperature and polarization angular power spectra of CMB measured by Atacama Cosmology Telescope (ACT) from 5400 deg$^2$ 2013-2016 survey, which covers $>$15000 at 98 150 GHz. For this analysis we adopt a blinding strategy to help avoid confirmation bias and, related this, show numerous checks for systematic error done before unblinding. Using likelihood cosmological constrain secondary sources anisotropy foreground emission, derive "CMB-only" spectrum that extends...
We present cosmological constraints from a gravitational lensing mass map covering 9400 sq. deg. reconstructed CMB measurements made by the Atacama Cosmology Telescope (ACT) 2017 to 2021. In combination with BAO (from SDSS and 6dF), we obtain amplitude of matter fluctuations $\sigma_8 = 0.819 \pm 0.015$ at 1.8% precision, $S_8\equiv\sigma_8({\Omega_{\rm m}}/0.3)^{0.5}=0.840\pm0.028$ Hubble constant $H_0= (68.3 1.1)\, \text{km}\,\text{s}^{-1}\,\text{Mpc}^{-1}$ 1.6% precision. A joint...
We present new measurements of cosmic microwave background (CMB) lensing over $9400$ sq. deg. the sky. These are derived from Atacama Cosmology Telescope (ACT) Data Release 6 (DR6) CMB dataset, which consists five seasons ACT temperature and polarization observations. determine amplitude power spectrum at $2.3\%$ precision ($43\sigma$ significance) using a novel pipeline that minimizes sensitivity to foregrounds noise properties. To ensure our results robust, we analyze an extensive set null...
Observations of the millimeter sky contain valuable information on a number signals, including blackbody cosmic microwave background (CMB), Galactic emissions, and Compton-y distortion due to thermal Sunyaev-Zel'dovich (tSZ) effect. Extracting new insight into cosmological astrophysical questions often requires combining multiwavelength observations spectrally isolate one component. In this work, we present arc-minute-resolution map, which traces out line-of-sight-integrated electron...
Abstract We investigate the impact and mitigation of extragalactic foregrounds for cosmic microwave background (CMB) lensing power spectrum analysis Atacama Cosmology Telescope (ACT) data release 6 (DR6) data. Two independent sky simulations are used to test a range strategies. demonstrate that finding then subtracting point sources, models clusters, using profile bias-hardened estimator together reduce fractional biases well below statistical uncertainties, with inferred amplitude, A lens ,...
The Probe of Inflation and Cosmic Origins (PICO) is a proposed probe-scale space mission consisting an imaging polarimeter operating in frequency bands between 20 800 GHz. We describe the science achievable by PICO, which has sensitivity equivalent to more than 3300 Planck missions, technical implementation, schedule cost.
Abstract We report the detection of 21 cm emission at an average redshift <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover accent="true"> <mml:mrow> <mml:mi>z</mml:mi> </mml:mrow> <mml:mo>¯</mml:mo> </mml:mover> <mml:mo>=</mml:mo> <mml:mn>2.3</mml:mn> </mml:math> in cross-correlation data from Canadian Hydrogen Intensity Mapping Experiment (CHIME) with measurements Ly α forest eBOSS. Data collected by CHIME over 88 days 400–500 MHz frequency band (1.8...
Massive cosmic neutrinos change the structure formation history by suppressing perturbations on small scales. Weak lensing data from galaxy surveys probe evolution and thereby can be used to constrain total mass of three active neutrinos. However, much information is at scales where dynamics are nonlinear. Traditional approaches with second-order statistics thus fail fully extract in field. In this paper, we study constraints neutrino sum using peak counts, a statistic which captures...
The Probe of Inflation and Cosmic Origins (PICO) is an imaging polarimeter that will scan the sky for 5 years in 21 frequency bands spread between 799 GHz. It produce full-sky surveys intensity polarization with a final combined-map noise level 0.87 $\mu$K arcmin required specifications, equivalent to 3300 Planck missions, our current best-estimate would have 0.61 (6400 missions). PICO either determine energy scale inflation by detecting tensor scalar ratio at $r=5\times 10^{-4}~(5\sigma)$,...
Massive neutrinos influence the background evolution of Universe as well growth structure. Being able to model this effect and constrain sum their masses is one key challenges in modern cosmology. Weak-lensing cosmological constraints will also soon reach higher levels precision with next-generation surveys like LSST, WFIRST Euclid. In context, we use massivenus simulations derive on neutrino ${M}_{\ensuremath{\nu}}$, present-day total matter density ${\mathrm{\ensuremath{\Omega}}}_{m}$,...
We study the effect of baryons on cosmic web -- halos, filaments, walls, and voids. To do so, we apply a modified version NEXUS, morphological analysis algorithm, to IllustrisTNG simulations. find that halos lose more than $10\%$ their mass due baryons, mostly filaments small portion walls However, transfer does not significantly shift boundaries structures, leaving volume fractions structures largely unaffected. quantify effects baryonic feedback power spectrum probability density function...
Abstract The increasing statistical power of cosmic microwave background (CMB) datasets requires a commensurate effort in understanding their noise properties. maps from ground-based instruments is dominated by large-scale correlations, which poses modeling challenge. This paper develops novel models the complex covariance structure Atacama Cosmology Telescope Data Release 6 (ACT DR6) maps. We first enumerate properties that arise combination atmosphere and ACT scan strategy. then prescribe...
Abstract We present simulated millimeter-wavelength maps and catalogs of radio galaxies across the full sky that trace nonlinear clustering evolution dark matter halos from Websky simulation at z < 4.6 M halo > 10 12 m ⊙ / h , accompanying framework for generating a new sample any catalog positions, redshifts, masses. Object fluxes are generated using hybrid approach combines (1) existing astrophysical models literature to determine positions rank-ordering observed with (2) empirical...
We forecast constraints on dark matter (DM) scattering with baryons in the early Universe upcoming and future cosmic microwave background (CMB) experiments, for DM particle masses down to 15 keV. In terms of upper limit interaction cross section a velocity-independent spin-independent elastic scattering, compared current Planck results, we find factor $\ensuremath{\sim}6$ improvement CMB-Stage 3, $\ensuremath{\sim}26$ 4, $\ensuremath{\sim}200$ cosmic-variance limited experiment. Once...
We present a new method for using measured X-ray emission line fluxes from O stars to determine the shock-heating rate due instabilities in their radiation-driven winds. The high densities of these winds means that embedded shocks quickly cool by local radiative emission, while cooling expansion should be negligible. Ignoring simplicity any non-radiative mixing or conductive cooling, presented here exploits idea post-shock plasma systematically passes through temperature characteristic...
Cosmic voids, the underdense regions in universe, are particularly sensitive to diffuse density components such as cosmic neutrinos. This sensitivity is enhanced by match between void sizes and free-streaming scale of massive Using neutrino simulations massivenus, we investigate effect mass on dark matter halos a function environment. We find that halo depends strongly this dependence more pronounced voids than high-density environments. An observational program measured characteristic most...
Abstract Diverse astrophysical observations suggest the existence of cold dark matter that interacts only gravitationally with radiation and ordinary baryonic matter. Any nonzero coupling between baryons would provide a significant step towards understanding particle nature Measurements cosmic microwave background (CMB) constraints on such complement laboratory searches. In this work we place upper limits variety models for elastic scattering protons electrons by combining large-scale CMB...
Abstract We present a cross-correlation analysis between <?CDATA $1^{\prime} $?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>1</mml:mn> <mml:mo accent="false">′</mml:mo> </mml:math> resolution total intensity and polarization observations from the Atacama Cosmology Telescope (ACT) at 150 220 GHz 15″ mid-infrared photometry Wide-field Infrared Survey Explorer (WISE) over 107 12.°5 × patches of sky. detect spatially isotropic signal in WISE×ACT TT...