1996/01/31 by C. B. Netterfield, Michelle Devlin, M. J. Devlin +5
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Radio Astronomy Observations and Technology #Scientific Research and Discoveries #astro-ph
paper · pdf · doi:10.1086/303438
published as Astrophys.J. 474 (1997) 47 · latex file is called spect.tex. 25 pages with 11 Postscript figures. Uses aas2pp4.sty (included). Submitted to ApJ
arxiv created 1996/02/01 · openalex publication_date 1997/01/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We report on a measurement of the angular power spectrum of the anisotropy in the cosmic microwave background (CMB). The anisotropy is measured in 23 different multipole bands from l = 54 (≈ 3°) to l = 404 (≈ 0 45) and in six frequency bands from 26 to 46 GHz over three observing seasons. The measurements are consistent from year to year. The frequency spectral index of the fluctuations (measured at low l ) is consistent with that of the CMB and inconsistent with either dust or Galactic free-free emission. Furthermore, the observations of the MSAM1-92 experiment (Cheng et al. 1994) are repeated and confirmed. The angular spectrum shows a distinct rise from δ T l ≡ [ l (2 l +1)⟨| a m l | 2 ⟩/4π] 1/2 =49 + 8 −5 μK at l = 87 to δ T l =85 + 10 −8 μK at l = 237. These values do not include an overall ±14% (1 σ) calibration uncertainty. The analysis and possible systematic errors are discussed.