C. A. Bischoff
A5075676474- Cosmology and Gravitation Theories
- Radio Astronomy Observations and Technology
- Superconducting and THz Device Technology
- Geophysics and Gravity Measurements
- Galaxies: Formation, Evolution, Phenomena
- Dark Matter and Cosmic Phenomena
- Astrophysics and Cosmic Phenomena
- Computational Physics and Python Applications
- Particle Accelerators and Free-Electron Lasers
- Astronomy and Astrophysical Research
- Pulsars and Gravitational Waves Research
- Black Holes and Theoretical Physics
- Spacecraft and Cryogenic Technologies
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Solar and Space Plasma Dynamics
- Astrophysics and Star Formation Studies
- Physics of Superconductivity and Magnetism
- Antenna Design and Optimization
- Precipitation Measurement and Analysis
- Geomagnetism and Paleomagnetism Studies
- Soil Moisture and Remote Sensing
- Advanced MIMO Systems Optimization
- Advanced Thermodynamic Systems and Engines
- Superconductivity in MgB2 and Alloys
University of Cincinnati
2017-2024
Center for Astrophysics Harvard & Smithsonian
2010-2017
University of Chicago
2005-2015
Harvard University Press
2014
(abridged for arXiv) We report results from the BICEP2 experiment, a cosmic microwave background (CMB) polarimeter specifically designed to search signal of inflationary gravitational waves in B-mode power spectrum around $\ell\sim80$. The telescope comprised 26 cm aperture all-cold refracting optical system equipped with focal plane 512 antenna coupled transition edge sensor 150 GHz bolometers each temperature sensitivity $\approx300\mu\mathrm{K}_\mathrm{CMB}\sqrt{s}$. observed South Pole...
We report the results of a joint analysis data from BICEP2/Keck Array and Planck. BICEP2 Keck have observed same approximately 400 deg$^2$ patch sky centered on RA 0h, Dec. $-57.5\deg$. The combined maps reach depth 57 nK deg in Stokes $Q$ $U$ band at 150 GHz. Planck has full polarization seven frequencies 30 to 353 GHz, but much less deeply any given region (1.2 $\mu$K 143 GHz). detect 150$\times$353 cross-correlation $B$-modes high significance. fit single- cross-frequency power spectra...
We present results from an analysis of all data taken by the BICEP2, Keck Array, and BICEP3 CMB polarization experiments up to including 2018 observing season. add additional Array observations at 220 GHz 95 previous 95/150/220 dataset. The Q/U maps now reach depths 2.8, 8.8 μK_{CMB} arcmin 95, 150, GHz, respectively, over effective area ≈600 square degrees ≈400 150 GHz. achieve a signal-to-noise ratio on polarized dust emission exceeding that Planck 353 take auto- cross-spectra between...
We present results from an analysis of all data taken by the BICEP2 and Keck Array cosmic microwave background (CMB) polarization experiments up to including 2014 observing season. This includes first observations at 95 GHz. The maps reach a depth 50 nK deg in Stokes Q U 150 GHz band 127 band. take auto- cross-spectra between these publicly available WMAP Planck frequencies 23 353 An excess over lensed ΛCDM is detected modest significance 95×150 BB spectrum, consistent with dust contribution...
We present the science case, reference design, and project plan for Stage-4 ground-based cosmic microwave background experiment CMB-S4.
This book lays out the scientific goals to be addressed by next-generation ground-based cosmic microwave background experiment, CMB-S4, envisioned consist of dedicated telescopes at South Pole, high Chilean Atacama plateau and possibly a northern hemisphere site, all equipped with new superconducting cameras. CMB-S4 will dramatically advance cosmological studies crossing critical thresholds in search for B-mode polarization signature primordial gravitational waves, determination number...
We present results from an analysis of all data taken by the bicep2/Keck CMB polarization experiments up to and including 2015 observing season. This includes first Keck Array observations at 220 GHz additional 95 150 GHz. The Q U maps reach depths 5.2, 2.9, 26 μKCMB arcmin 95, 150, GHz, respectively, over effective area ≈400 square degrees. achieve a signal noise on polarized dust emission approximately equal that Planck 353 take auto cross spectra between these publicly available WMAP...
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...
Abstract The tightest constraints on the tensor-to-scalar ratio r can only be obtained after removing a substantial fraction of lensing B -mode sample variance. planned Cosmic Microwave Background (CMB)-S4 experiment ( cmb-s4.org ) will remove signal internally by reconstructing gravitational lenses from high-resolution observations. We document here first reconstruction pipeline able to achieve this optimally for arbitrary sky coverage. make it part map-based framework test CMB-S4 delensing...
We report on the design and performance of BICEP2 instrument its three-year data set. was designed to measure polarization cosmic microwave background (CMB) angular scales 1 5 degrees ($\ell$=40-200), near expected peak B-mode signature primordial gravitational waves from inflation. Measuring B-modes requires dramatic improvements in sensitivity combined with exquisite control systematics. The telescope observed South Pole a 26~cm aperture cold, on-axis, refractive optics. also adopted new...
The Keck Array is a system of cosmic microwave background polarimeters, each similar to the Bicep2 experiment. In this paper we report results from 2012 2013 observing seasons, during which consisted five receivers all operating in same (150 GHz) frequency band and field as Bicep2. We again find an excess B-mode power over lensed-ΛCDM expectation >5σ range 30 < ℓ 150 confirm that not due systematics using jackknife tests simulations based on detailed calibration measurements. map difference...
We report on the design and performance of BICEP3 instrument its first three-year data set collected from 2016 to 2018. is a 52cm aperture, refracting telescope designed observe polarization cosmic microwave background (CMB) degree angular scales at 95GHz. It started science observation South Pole in with 2400 antenna-coupled transition-edge sensor (TES) bolometers. The receiver demonstrated new technologies such as large-diameter alumina optics, Zotefoam infrared filters, flux-activated...
The Q/U Imaging ExperimenT (QUIET) employs coherent receivers at 43GHz and 95GHz, operating on the Chajnantor plateau in Atacama Desert Chile, to measure anisotropy polarization of CMB. QUIET primarily targets B modes from primordial gravitational waves. combination these frequencies gives sensitivity foreground contributions diffuse Galactic synchrotron radiation. Between 2008 October 2010 December, >10,000hours data were collected, first with 19-element array (3458hours) then 90-element...
Cosmic microwave background (CMB) polarimeters aspire to measure the faint B-mode signature predicted arise from inflationary gravitational waves. They also have potential constrain cosmic birefringence, rotation of polarization CMB arising parity-violating physics, which would produce nonzero expectation values for CMB's temperature correlation (TB) and E-mode (EB) spectra. However, instrumental systematic effects can cause these TB EB correlations be nonzero. In particular, an overall...
Our current understanding of the Universe is established through pristine measurements structure in cosmic microwave background (CMB) and distribution shapes galaxies tracing large scale (LSS) Universe. One key ingredient that underlies cosmological observables field sources observed assumed to be initially Gaussian with high precision. Nevertheless, a minimal deviation from Gaussianityis perhaps most robust theoretical prediction models explain Universe; itis necessarily present even...
Our current understanding of the Universe is established through pristine measurements structure in cosmic microwave background (CMB) and distribution shapes galaxies tracing large scale (LSS) Universe. One key ingredient that underlies cosmological observables field sources observed assumed to be initially Gaussian with high precision. Nevertheless, a minimal deviation from Gaussianityis perhaps most robust theoretical prediction models explain Universe; itis necessarily present even...
We present estimates of line-of-sight distortion fields derived from the 95 GHz and 150 data taken by BICEP2, BICEP3, Keck Array up to 2018 observing season, leading cosmological constraints a study instrumental astrophysical systematics. Cosmological are three concerning gravitational lensing large-scale structure, polarization rotation magnetic or an axion-like field, screening effect patchy reionization. measure amplitude power spectrum $A_L^{\phi\phi}=0.95 \pm 0.20$. constrain rotation,...
We present new measurements of the cosmic microwave background (CMB) polarization from final season Cosmic Anisotropy Polarization MAPper (CAPMAP). The data set was obtained in winter 2004-2005 with 7 m antenna Crawford Hill, New Jersey, 12 W-band (84-100 GHz) and 4 Q-band (36-45 correlation polarimeters 3.3' 6.5' beamsizes, respectively. After selection criteria were applied, 956 (939) hours survived for analysis (Q-band) data. Two independent complementary pipelines produced results...
The Q/U Imaging ExperimenT (QUIET) has observed the cosmic microwave background (CMB) at 43 and 95GHz. 43-GHz results have been published in QUIET Collaboration et al. (2011), here we report measurement of CMB polarization power spectra using 95-GHz data. This data set comprises 5337 hours observations recorded by an array 84 polarized coherent receivers with a total sensitivity 87 uK sqrt(s). Four low-foreground fields were observed, covering ~1000 square degrees effective angular...
The Q/U Imaging ExperimenT (QUIET) is designed to measure polarization in the Cosmic Microwave Background, targeting imprint of inflationary gravitational waves at large angular scales (~ 1 degree). Between 2008 October and 2010 December, two independent receiver arrays were deployed sequentially on a 1.4 m side-fed Dragonian telescope. polarimeters which form focal planes use highly compact design based High Electron Mobility Transistors (HEMTs) that provides simultaneous measurements...
ABSTRACT We present measurements of polarization lensing using the 150 GHz maps, which include all data taken by BICEP2 and Keck Array Cosmic Microwave Background experiments up to including 2014 observing season (BK14). Despite their modest angular resolution ( ), excellent sensitivity (∼3 μ K-arcmin) these maps makes it possible directly reconstruct potential only information at larger scales ). From auto-spectrum reconstructed potential, we measure an amplitude spectrum be Planck ΛCDM...
CMB-S4 is a proposed experiment to map the polarization of Cosmic Microwave Background (CMB) nearly cosmic variance limit for angular scales that are accessible from ground. The science goals and capabilities in illuminating inflation, measuring sum neutrino masses, searching relativistic relics early universe, characterizing dark energy matter, mapping matter distribution universe have been described Science Book. This Technology Book companion volume ambitious CMB-S4, "Stage-4" experiment,...