A measurement of the large-scale cosmic microwave background anisotropy at 1. 8 millimeter wavelength

Journal Article · Mon Apr 01 04:00:00 EST 1991 · Astrophysical Journal; (United States)

DOI:https://doi.org/10.1086/185989· OSTI ID:5666513

Meyer, S S; Cheng, E S; Page, L A ^[1]

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1. MIT, Cambridge, MA (USA)

This measurement of the large-scale cosmic microwave background radiation (CMBR) anisotropy places the most stringent constraints to date on fluctuations in the CMBR on angular scales greater than about 4 deg. Using a four-channel bolometric radiometer operating at 1.8, 1.1, 0.63, and 0.44 mm, the diffuse sky brightness over half of the northern hemisphere has been mapped with an angular resolution of 3.8 deg. Analysis of the sky map at the longest wavelength for Galactic latitudes of 15 deg or more yields a 95-percent confidence level upper limit on fluctuations of the CMBR at Delta T/T of 1.6 x 10 to the -5th with a statistical power of 92 percent for Gaussian fluctuations at a correlation angle of 13 deg. Between 3 deg and 22 deg, the upper limit of fluctuations is 4.0 x 10 to the -5th . An anisotropy is detected in the map, but it cannot yet be attributed to primordial sources. The ultimate sensitivity for this experiment is 7 x 10 to the -6th over this angular range for Gaussian fluctuations. 13 refs.

• OSTI ID: 5666513
• Journal Information: Astrophysical Journal; (United States), Journal Name: Astrophysical Journal; (United States) Vol. 371; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640106* -- Astrophysics & Cosmology-- Cosmology
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANISOTROPY
BACKGROUND RADIATION
BOLOMETERS
COSMOLOGY
ELECTROMAGNETIC RADIATION
GALAXIES
LIMITING VALUES
MAPS
MEASURING INSTRUMENTS
MICROWAVE RADIATION
MILKY WAY
RADIATION DETECTORS
RADIATIONS
RADIOMETERS
RELICT RADIATION