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Title: BICEP2. II. Experiment and three-year data set

We report on the design and performance of the BICEP2 instrument and on its three-year data set. BICEP2 was designed to measure the polarization of the cosmic microwave background (CMB) on angular scales of 1°-5°(ℓ = 40-200), near the expected peak of the B-mode polarization signature of primordial gravitational waves from cosmic inflation. Measuring B-modes requires dramatic improvements in sensitivity combined with exquisite control of systematics. The BICEP2 telescope observed from the South Pole with a 26 cm aperture and cold, on-axis, refractive optics. BICEP2 also adopted a new detector design in which beam-defining slot antenna arrays couple to transition-edge sensor (TES) bolometers, all fabricated on a common substrate. The antenna-coupled TES detectors supported scalable fabrication and multiplexed readout that allowed BICEP2 to achieve a high detector count of 500 bolometers at 150 GHz, giving unprecedented sensitivity to B-modes at degree angular scales. After optimization of detector and readout parameters, BICEP2 achieved an instrument noise-equivalent temperature of 15.8 μK√s. The full data set reached Stokes Q and U map depths of 87.2 nK in square-degree pixels (5.'2 μK) over an effective area of 384 deg{sup 2} within a 1000 deg{sup 2} field. These are the deepest CMB polarization maps atmore » degree angular scales to date. The power spectrum analysis presented in a companion paper has resulted in a significant detection of B-mode polarization at degree scales.« less
Authors:
 [1] ; ; ; ; ; ;  [2] ; ; ; ;  [3] ;  [4] ;  [5] ; ;  [6] ;  [7] ; ;  [8] ;  [9] ;  [10] more »; ; « less
  1. School of Physics and Astronomy, Cardiff University, Cardiff, CF24 3AA (United Kingdom)
  2. Department of Physics, California Institute of Technology, Pasadena, CA 91125 (United States)
  3. Department of Physics and Astronomy, University of British Columbia, Vancouver, BC (Canada)
  4. Joint ALMA Observatory, ESO, Santiago (Chile)
  5. Department of Physics, University of Toronto, Toronto, ON (Canada)
  6. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street MS 42, Cambridge, MA 02138 (United States)
  7. Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455 (United States)
  8. Jet Propulsion Laboratory, Pasadena, CA 91109 (United States)
  9. Université Grenoble Alpes, CEA INAC-SBT, F-38000 Grenoble (France)
  10. Department of Physics, University of Minnesota, Minneapolis, MN 55455 (United States)
Publication Date:
OSTI Identifier:
22365196
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 792; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; APERTURES; BACKGROUND RADIATION; BOLOMETERS; COSMOLOGY; DETECTION; GRAVITATIONAL WAVES; INFLATIONARY UNIVERSE; MAPS; NOISE; OPTICS; OPTIMIZATION; POLARIMETERS; POLARIZATION; RELICT RADIATION; SENSITIVITY; SPECTRA; SUBSTRATES; TELESCOPES