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Daily quality assurance software for a satellite radiometer systemSix Differential Microwave Radiometers (DMR) on COBE (Cosmic Background Explorer) measure the large-angular-scale isotropy of the cosmic microwave background (CMB) at 31.5, 53, and 90 GHz. Quality assurance software analyzes the daily telemetry from the spacecraft to ensure that the instrument is operating correctly and that the data are not corrupted. Quality assurance for DMR poses challenging requirements. The data are differential, so a single bad point can affect a large region of the sky, yet the CMB isotropy requires lengthy integration times (greater than 1 year) to limit potential CMB anisotropies. Celestial sources (with the exception of the moon) are not, in general, visible in the raw differential data. A 'quicklook' software system was developed that, in addition to basic plotting and limit-checking, implements a collection of data tests as well as long-term trending. Some of the key capabilities include the following: (1) stability analysis showing how well the data RMS averages down with increased data; (2) a Fourier analysis and autocorrelation routine to plot the power spectrum and confirm the presence of the 3 mK 'cosmic' dipole signal; (3) binning of the data against basic spacecraft quantities such as orbit angle; (4) long-term trending; and (5) dipole fits to confirm the spacecraft attitude azimuth angle.
Document ID
19930009527
Acquisition Source
Legacy CDMS
Document Type
Other
Authors
Keegstra, P. B.
(California Univ. Berkeley, CA, United States)
Smoot, G. F.
(California Univ. Berkeley, CA, United States)
Bennett, C. L.
(California Univ. Berkeley, CA, United States)
Aymon, J.
(California Univ. Berkeley, CA, United States)
Backus, C.
(California Univ. Berkeley, CA, United States)
Deamici, G.
(California Univ. Berkeley, CA, United States)
Hinshaw, G.
(California Univ. Berkeley, CA, United States)
Jackson, P. D.
(California Univ. Berkeley, CA, United States)
Kogut, A.
(California Univ. Berkeley, CA, United States)
Lineweaver, C.
(California Univ. Berkeley, CA, United States)
Date Acquired
September 6, 2013
Publication Date
December 1, 1992
Publication Information
Publication: NASA. Goddard Space Flight Center, Goddard Visiting Scientist Program for the Space and Earth Sciences Directorate
Subject Category
Computer Programming And Software
Accession Number
93N18716
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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