A Measurement of the MediumScale Anisotropy in the Cosmic Microwave Background Radiation
Abstract
Observations from the first flight of the Medium Scale Anisotropy Measurement (MSAM) are analyzed to place limits on Gaussian fluctuations in the cosmic microwave background radiation (CMBR). This instrument chops a 30' beam in a threeposition pattern with a throw of +/ 40'; the resulting data is analyzed in statistically independent single and doubledifference data sets. We observe in four spectral channels at 5.6, 9.0, 16.5, and 22.5 cm ^1^, allowing the separation of interstellar dust emission from CMBR fluctuations. The dust component is correlated with the IRAS 100 micron map. The CMBR component has two regions where the signature of an unresolved source is seen. Rejecting these two source regions, we obtain a detection of fluctuations which match CMBR in our spectral bands of 0.6 x 10^5^ < {DELTA}T/T < 2.2 x 10^5^ (90% CL interval) for total rms Gaussian fluctuations with correlation angle 0.5^deg^, using the singledifference demodulation. For the double difference demodulation, the result is 1.1 x 10^5^< {DELTA}T/T < 3.1 x 10^5^(90% CL interval) at a correlation angle of 0.3^deg^.
 Publication:

The Astrophysical Journal
 Pub Date:
 February 1994
 DOI:
 10.1086/187206
 arXiv:
 arXiv:astroph/9305022
 Bibcode:
 1994ApJ...422L..37C
 Keywords:

 Anisotropy;
 Background Radiation;
 Cosmic Rays;
 Cosmology;
 Microwaves;
 Sky Brightness;
 BalloonBorne Instruments;
 Interstellar Matter;
 Probability Density Functions;
 Spectral Signatures;
 Spectrum Analysis;
 Astrophysics;
 COSMOLOGY: COSMIC MICROWAVE BACKGROUND;
 COSMOLOGY: OBSERVATIONS;
 Astrophysics
 EPrint:
 13 pages + 3 figures (included), LaTeX + AASTeX v3.0