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Title: A measurement of the secondary-CMB and millimeter-wave-foreground bispectrum using 800 deg{sup 2} of south pole telescope data

We present a measurement of the angular bispectrum of the millimeter-wave sky in observing bands centered at roughly 95, 150, and 220 GHz, on angular scales of 1' ≲ θ ≲ 10' (multipole number 1000 ≲ l ≲ 10,000). At these frequencies and angular scales, the main contributions to the bispectrum are expected to be the thermal Sunyaev-Zel'dovich (tSZ) effect and emission from extragalactic sources, predominantly dusty, star-forming galaxies (DSFGs) and active galactic nuclei. We measure the bispectrum in 800 deg{sup 2} of three-band South Pole Telescope data, and we use a multi-frequency fitting procedure to separate the bispectrum of the tSZ effect from the extragalactic source contribution. We simultaneously detect the bispectrum of the tSZ effect at >10σ, the unclustered component of the extragalactic source bispectrum at >5σ in each frequency band, and the bispectrum due to the clustering of DSFGs—i.e., the clustered cosmic infrared background (CIB) bispectrum—at >5σ. This is the first reported detection of the clustered CIB bispectrum. We use the measured tSZ bispectrum amplitude, compared to model predictions, to constrain the normalization of the matter power spectrum to be σ{sub 8} = 0.787 ± 0.031 and to predict the amplitude of the tSZ power spectrum atmore » l = 3000. This prediction improves our ability to separate the thermal and kinematic contributions to the total SZ power spectrum. The addition of bispectrum data improves our constraint on the tSZ power spectrum amplitude by a factor of two compared to power spectrum measurements alone and demonstrates a preference for a nonzero kinematic SZ (kSZ) power spectrum, with a derived constraint on the kSZ amplitude at l = 3000 of A {sub kSZ} = 2.9 ± 1.6 μK{sup 2}, or A {sub kSZ} = 2.6 ± 1.8 μK{sup 2} if the default A {sub kSZ} > 0 prior is removed.« less
Authors:
; ; ; ; ; ; ; ;  [1] ; ;  [2] ;  [3] ; ; ; ;  [4] ; ;  [5] ;  [6] ;  [7] more »; « less
  1. Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637 (United States)
  2. University of Chicago, Chicago, IL 60637 (United States)
  3. NIST Quantum Devices Group, Boulder, CO 80305 (United States)
  4. Department of Physics, McGill University, Montreal, Quebec H3A 2T8 (Canada)
  5. Department of Physics, University of California, Berkeley, CA 94720 (United States)
  6. Department of Astrophysical and Planetary Sciences and Department of Physics, University of Colorado, Boulder, CO 80309 (United States)
  7. Department of Physics, University of California, Davis, CA 95616 (United States)
Publication Date:
OSTI Identifier:
22357264
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 784; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMPLITUDES; BACKGROUND RADIATION; COMPARATIVE EVALUATIONS; COSMOLOGY; DATA ANALYSIS; DETECTION; EMISSION; FORECASTING; GALAXIES; GALAXY NUCLEI; GHZ RANGE; LIMITING VALUES; SPECTRA; STARS; TELESCOPES