We present measurements of cosmic microwave background (CMB) anisotropy near the stars HR 5127 and Herculis from the fifth flight of the Millimeter-wave Anisotropy eXperiment (MAX). We scanned 8 strips of the sky with an approximately Gaussian 0$5 FWHM beam and a 1$4 peak to peak sinusoidal chop. The instrument has four frequency bands centered at 3.5, 6, 9, and 14 cm1. The IRAS100 m map predicts that these two regions have low interstellar dust contrast. The HR 5127 data are consistent with CMB anisotropy. The Herculis data, which were measured at lower flight altitudes, show time variability at 9 and 14 cm1, which we believe to be due to atmospheric emission. However, the Herculis data at 3.5 and 6 cm1 are essentially independent of this atmospheric contribution and are consistent with CMB anisotropy. Confusion from Galactic foregrounds is unlikely based on the spectrum and amplitude of the structure at these frequencies. If the observed HR 5127 structure and the atmosphere-independent Herculis structure are attributed to CMB anisotropy, then we find T/T l(l 1)Cl/21/2 18.104.22.168 105 for HR 5127 and 22.214.171.124 105 for Herculis in the flat band approximation. The upper and lower limits represent a 68% confidence interval added in quadrature with a 10% calibration uncertainty.
Bibliographical noteFunding Information:
This work was supported by the National Science Foundation through the Center for Particle Astrophysics (cooperative agreement AST 91-20005), the National Aeronautics and Space Administration under grants NAGW-1062 and FD-NAGW-2121, the University of California, and previously the California Space Institute. N. F. was partially supported by Conselho Nacional de Desenvolvimento Científico e Tecno-lógico, Brazil. We would like to thank O. Levy for his assistance with the flight preparation, the MSAM team for borrowed equipment and discussions, and M. White.
© 1996. The American Astronomical Society. All rights reserved.
- Cosmic microwave background
- cosmology: observations