Cosmic Microwave Background Anisotropy Measurements with the OVRO 5.5m Telescope
Session 118 -- Cosmic Micorwave Background
Oral presentation, Thursday, 12, 1995, 2:00pm - 3:30pm

## [118.04] Cosmic Microwave Background Anisotropy Measurements with the OVRO 5.5m Telescope

E.M. Leitch, S.T. Myers, A.C.S. Readhead (Caltech)

The results of an experiment to measure anisotropy in the cosmic microwave background on arcminute scales are presented. These observations were conducted at the Owens Valley Radio Observatory using the new 5.5m telescope (32GHz, $7.\mkern-4mu^\prime3$ beam, $22.\mkern-4mu^\prime16$ beamthrow) and have reached a noise level of $27\,\mu\mbox{K}$ in each of 36 interlocked fields. Fluctuations of up to $86\,\mu\mbox{K}$ over noise are detected in the RING5M experiment, much of which is most likely attributable to contamination by point sources (radio galaxies and quasars), and by synchrotron emission from the galaxy.

A new 13-16 GHz Ku-band system, matched to the 5.5m beam and beamthrow, has been installed on the OVRO 40m telescope to search the RING5M fields for foreground contamination of the microwave background data. First results from the Ku-band data are presented.

Contamination by discrete (extragalactic) sources was investigated using drift-scan surveys, conducted on the 40m telescope, of the RING5M fields at 18.5 GHz. The latest results from these drift-scans, as well as results from a VLA survey of the RING5M fields at X-band, are reported.