CARMA Memo #57

Blank Sky Analysis and Statistics
Kevin P. Rauch and Demerese M. Salter
Astronomy Dept, University of Maryland, College Park 

This memo gives an overview of the blank sky task, data analysis details,
and performance expectations. Details of the digital quantization schemes
implemented by the CARMA correlator, which determine the expected noise
levels, are also provided. We note that previous attempts to use noise
source spectra for real-time bandpass calibration may have been biased by
failure to correct for on-sky thresholding variations, which we find is
necessary to accurately reproduce predicted noise statistics. Including these
corrections, blank sky results generally agree with expectations to within ~1%.