Patricio A. Gallardo
A5043086912- Radio Astronomy Observations and Technology
- Superconducting and THz Device Technology
- Galaxies: Formation, Evolution, Phenomena
- Cosmology and Gravitation Theories
- Astronomy and Astrophysical Research
- Astrophysics and Cosmic Phenomena
- Astrophysics and Star Formation Studies
- Adaptive optics and wavefront sensing
- Dark Matter and Cosmic Phenomena
- Algebraic Geometry and Number Theory
- Astronomical Observations and Instrumentation
- Stellar, planetary, and galactic studies
- Microwave Engineering and Waveguides
- Antenna Design and Optimization
- Physics of Superconductivity and Magnetism
- Geophysics and Gravity Measurements
- Gamma-ray bursts and supernovae
- Advanced Algebra and Geometry
- Homotopy and Cohomology in Algebraic Topology
- Optical Coatings and Gratings
- Astrophysical Phenomena and Observations
- Photonic and Optical Devices
- Radio Frequency Integrated Circuit Design
- Geometry and complex manifolds
- Climate variability and models
University of Chicago
2022-2024
Columbia University
2023
University of Michigan
2023
Kavli Institute for Particle Astrophysics and Cosmology
2023
University of California, Riverside
2023
Cornell University
2014-2022
Lincoln Medical Center
2020
Pontificia Universidad Católica de Chile
2012-2018
Princeton University
2013
The Simons Observatory (SO) is a new cosmic microwave background experiment being built on Cerro Toco in Chile, due to begin observations the early 2020s. We describe scientific goals of experiment, motivate design, and forecast its performance. SO will measure temperature polarization anisotropy six frequency bands: 27, 39, 93, 145, 225 280 GHz. initial configuration have three small-aperture 0.5-m telescopes (SATs) one large-aperture 6-m telescope (LAT), with total 60,000 cryogenic...
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 constraints on cosmological and astrophysical parameters from high-resolution microwave background maps at 148 GHz 218 made by the Atacama Cosmology Telescope (ACT) in three seasons of observations 2008 to 2010. A model primary secondary foreground is fit map power spectra lensing deflection spectrum, including contributions both thermal Sunyaev-Zeldovich (tSZ) effect kinematic (kSZ) effect, Poisson correlated anisotropy unresolved infrared sources, radio correlation between tSZ...
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 $>$15000 at 98 150 GHz. For this analysis we adopt a blinding strategy to help avoid confirmation bias and, related this, show numerous checks for systematic error done before unblinding. Using likelihood cosmological constrain secondary sources anisotropy foreground emission, derive "CMB-only" spectrum that extends...
We present the temperature and polarization angular power spectra measured by Atacama Cosmology Telescope Polarimeter (ACTPol). analyze night-time data collected during 2013-14 using two detector arrays at 149 GHz, from 548 deg$^2$ of sky on celestial equator. use these spectra, with MBAC camera ACT 2008-10, in combination Planck WMAP to estimate cosmological parameters temperature, polarization, temperature-polarization cross-correlations. find new ACTPol be consistent LCDM model. The...
Abstract 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 origin evolution universe. Among science cases pursued with CMB-S4, quest for detecting primordial gravitational waves is a central driver experimental design. This work details development forecasting framework that includes power-spectrum-based semianalytic projection tool, targeted explicitly toward...
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...
The imprint left on the cosmic microwave background (CMB) from CMB photons scattering off high-energy electrons in galaxies and clusters is known as Sunyaev-Zel'dovich (SZ) effect subject of these two papers Atacama Cosmology Telescope (ACT). ACT measurements combined with those Planck BOSS are shown to provide a rich picture electron gas thermodynamics galactic cluster medium. This can be used test improve cosmological simulations relevant for upcoming experiments.
The early dark energy (EDE) scenario aims to increase the value of Hubble constant (${H}_{0}$) inferred from cosmic microwave background (CMB) data over that found in standard cosmological model ($\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$), via introduction a new form density Universe. EDE component briefly accelerates expansion just prior recombination, which reduces physical size sound horizon imprinted CMB. Previous work has nonzero is not preferred by Planck CMB power spectrum alone,...
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...
The (sub)millimeter sky contains a vast wealth of information that is both complementary and inaccessible to other wavelengths. Over half the light we receive observable at millimeter submillimeter wavelengths, yet have mapped only small portion sufficient spatial resolution sensitivity detect resolve distant galaxies or star-forming cores within their large- scale environments. For decades, astronomical community has highlighted need for large, high-throughput ( λ ~ 0.35–10 mm) single dish....
We report on measurements of the cosmic microwave background (CMB) and celestial polarization at 146 GHz made with Atacama Cosmology Telescope Polarimeter (ACTPol) in its first three months observing. Four regions sky covering a total 270 square degrees were mapped an angular resolution $1.3'$. The map noise levels four are between 11 17 $\mu$K-arcmin. present TT, TE, EE, TB, EB, BB power spectra from these regions. observed E-mode spectrum, displaying six acoustic peaks range...
The Atacama Cosmology Telescope (ACT) is designed to make high angular resolution measurements of anisotropies in the Cosmic Microwave Background (CMB) at millimeter wavelengths. We describe ACTPol, an upgraded receiver for ACT, which uses feedhorn-coupled, polarization-sensitive detector arrays, a 3 degree field view, 100 mK cryogenics with continuous cooling, and meta material anti-reflection coatings. ACTPol comprises three arrays separate cryogenic optics: two central frequency 148 GHz...
We report a measurement of the power spectrum cosmic microwave background (CMB) lensing from two seasons Atacama Cosmology Telescope Polarimeter (ACTPol) CMB data. The is extracted both temperature and polarization data using quadratic estimators. obtain results that are consistent with expectation best-fit Planck LCDM model over range multipoles L=80-2100, an amplitude A_lens = 1.06 +/- 0.15 (stat.) 0.06 (sys.) relative to Planck. Our gives sigma_8 Omega_m^0.25 0.643 0.054; including baryon...
We use microwave temperature maps from two seasons of data the Atacama Cosmology Telescope (ACTPol) at 146 GHz, together with Constant Mass CMASS galaxy sample Baryon Oscillation Spectroscopic Survey to measure kinematic Sunyaev-Ze\v{l}dovich (kSZ) effect over redshift range z = 0.4 - 0.7. positions and continuity equation obtain a reconstruction line-of-sight velocity field. stack cosmic background location each halo, weighted by corresponding reconstructed velocity. The resulting best fit...
We present constraints on the primordial power spectrum of adiabatic fluctuations using data from 2008 Southern Survey Atacama Cosmology Telescope (ACT). The angular resolution ACT provides sensitivity to scales beyond \ell = 1000 for multiple peaks in temperature spectrum, which enables us probe scalar perturbations with wavenumbers up k \simeq 0.2 Mpc^{-1}. find no evidence deviation power-law over two decades scale. Matter inferred evolve cosmic time and can be used predict matter at late...
The thermal and kinematic Sunyaev-Zel'dovich effects (tSZ, kSZ) probe the thermodynamic properties of circumgalactic intracluster medium (CGM ICM) galaxies, groups, clusters, since they are proportional, respectively, to integrated electron pressure momentum along line-of-sight. We present constraints on gas thermodynamics CMASS galaxies in Baryon Oscillation Spectroscopic Survey (BOSS) using new measurements kSZ tSZ signals obtained a companion paper. Combining measurements, we measure...
We present a catalog of 182 galaxy clusters detected through the Sunyaev-Zel'dovich effect by Atacama Cosmology Telescope in contiguous 987.5 deg$^{2}$ field. The were as SZ decrements applying matched filter to 148 GHz maps that combine original ACT equatorial survey with data from first two observing seasons using ACTPol receiver. Optical/IR confirmation and redshift measurements come combination large public surveys our own follow-up observations. Where necessary, we measured photometric...
We construct cosmic microwave background lensing mass maps using data from the 2014 and 2015 seasons of observations with Atacama Cosmology Telescope (ACT). These cover 2100 square degrees sky overlap a wide variety optical surveys. The are signal dominated on large scales have fidelity such that their correlation infrared is clearly visible by eye. also create thermal Sunyaev-Zel'dovich contamination removed novel cleaning procedure only slightly degrades signal-to-noise ratio....
The Simons Observatory (SO) is a ground-based cosmic microwave background (CMB) experiment sited on Cerro Toco in the Atacama Desert Chile that promises to provide breakthrough discoveries fundamental physics, cosmology, and astrophysics. Supported by Foundation, Heising-Simons with contributions from collaborating institutions, SO will see first light 2021 start five year survey 2022. has 287 collaborators 12 countries 53 including 85 students 90 postdocs. its currently funded form...
Optimal analyses of many signals in the cosmic microwave background (CMB) require map-level extraction individual components sky, rather than measurements at power spectrum level alone. To date, nearly all component separation CMB has been performed exclusively using satellite data. In this paper, we implement a method based on internal linear combination (ILC) approach which have designed to optimally account for anisotropic noise (in 2D Fourier domain) often found ground-based experiments....
This paper presents a maximum-likelihood algorithm for combining sky maps with disparate coverage, angular resolution and spatially varying anisotropic noise into single map of the sky. We use this to merge hundreds individual covering 2008-2018 ACT observing seasons, resulting in by far deepest released so far. also combine full Planck maps, that have best features both ACT: Planck's nearly white on intermediate large scales ACT's high-resolution sensitivity small scales. The cover over...
Abstract We present a detailed overview of the science goals and predictions for Prime-Cam direct-detection camera–spectrometer being constructed by CCAT-prime collaboration dedicated use on Fred Young Submillimeter Telescope (FYST). The FYST is wide-field, 6 m aperture submillimeter telescope built (first light in late 2023) an international consortium institutions led Cornell University sited at more than 5600 Cerro Chajnantor northern Chile. one two instruments planned will provide...