Characterization of the MALT90 Survey and the Mopra Telescope at 90 GHz
  We characterize the Millimeter Astronomy Legacy Team 90 GHz (MALT90) Survey
and the Mopra telescope at 90 GHz. We combine repeated position-switched
observations of the source G300.968+01.145 with a map of the same source in
order to estimate the pointing reliability of the position-switched
observations and, by extension, the MALT90 survey; we estimate our pointing
uncertainty to be 8 arcseconds. We model the two strongest sources of
systematic gain variability as functions of elevation and time-of-day and
quantify the remaining absolute flux uncertainty. Corrections based on these
two variables reduce the scatter in repeated observations from 12-25% down to
10-17%. We find no evidence for intrinsic source variability in
G300.968+01.145. For certain applications, the corrections described herein
will be integral for improving the absolute flux calibration of MALT90 maps and
other observations using the Mopra telescope at 90 GHz.
