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Search for unresolved sources in the COBE-DMR two-year sky mapsWe have searched the temperature maps from the Cosmic Background Explorer (COBE) Differential Microwave Radiometers (DMR) first two years of data for evidence of unresolved sources. The high-latitude sky (absolute value of b greater than 30 deg) contains no sources brighter than 192 microKelvin thermodynamic temperature (322 Jy at 53 GHz). The cumulative count of sources brighter than threshold T, N(greater than T), is consistent with a superposition of instrument noise plus scale-invariant spectrum of cosmic temperature fluctuations normalized to Q(sub rms-PS) = 17 microKelvin. We examine the temperature maps toward nearby clusters and find no evidence for any Sunyaev-Zel'dovich effect, delta y less than 7.3 x 10(exp -6) (95% CL) averaged over the DMR beam. We examine the temperature maps near the brightest expected radio sources and detect no evidence of significant emission. The lack of bright unresolved sources in the DMR maps, taken with anisotropy measurements on smaller angular scales, places a weak constraint on the integral number density of any unresolved Planck-spectrum sources brighter than flux density S, n(greater than S) less than 2 x 10(exp 4)/(S/1 Jy)(exp 2)/sr.
Document ID
19950040843
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Kogut, A.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Banday, A. J.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Bennett, C. L.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Hinshaw, G.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Loewenstein, K.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Lubin, P.
(UCSB Physics Department, Santa Barbara, CA United States)
Smoot, G. F.
(University of California, Berkeley, CA United States)
Wright, E. L.
(UCLA Astronomy Department, Los Angeles, CA United States)
Date Acquired
August 16, 2013
Publication Date
October 1, 1994
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 433
Issue: 2
ISSN: 0004-637X
Subject Category
Astronomy
Accession Number
95A72442
Distribution Limits
Public
Copyright
Other

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