A Sky Temperature Survey at 19.2 GHZ Using a Balloon Borne Dicke Radiometer for Anisotropy Tests of the Cosmic Microwave Background.
Abstract
This thesis describes a large area sky survey at a resolution of 3^circ carried out with a balloon borne Dicke radiometer using a liquid helium cooled ruby maser amplifier. The instrument and method of observation are described. The data from one flight of the instrument are analyzed to produce a map of sky temperature covering roughly declination -15^circ to +75^circ and right ascension 7^{rm h} to 23^{rm h} at a typical sensitivity of 1.5 mK per 3 ^circ times 3^circ resolution element. The calibration of this map in terms of antenna temperature is accurate to 3%. Analysis of the sky map indicates that the components of the dipole anisotropy of the cosmic microwave background (CMB) are (in thermodynamic temperature) {cal T}x = -3.46 +/- 0.09 mK, {cal T}y = 0.41 +/- 0.07 mK, { cal T}z = -0.50 +/- 0.08 mK, implying that the magnitude is |{cal T}| = 3.52 +/-.08 mK and has its bright pole at alpha = 11^{rm h} 33 ^{rm m} +/- 06^{rm m}, delta = -8.2^circ +/- 1.5^circ (statistical errors). These data place an upper bound of Delta T / T < 2 times 10^{ -4} (95% confidence level) on anisotropy of the CMB other than the dipole at all angular scales greater than 3^circ..
- Publication:
-
Ph.D. Thesis
- Pub Date:
- 1987
- Bibcode:
- 1987PhDT.........4C
- Keywords:
-
- Physics: Astronomy and Astrophysics;
- Anisotropy;
- Background Radiation;
- Mapping;
- Microwaves;
- Sky Surveys (Astronomy);
- Temperature Measurement;
- Balloon-Borne Instruments;
- Calibrating;
- Dicke Radiometers;
- Space Radiation