Check for timing shifts A check for timing shifts of PACS photometer data vs. pointing product

Dieter Lutz
2012 unpublished
A large sample of ∼600 scan maps is used to search for timing offsets between PACS data and pointing information. This is done by comparing the positions measured in separate maps created from the 'odd' scanlegs for which the telescope is moving in one direction and the 'even' scanlegs where it is moving in the opposite direction. While these positions clearly differ by ∼1 arcsec RMS, likely due to pointing uncertainties, there is no clear systematic offset in scan direction, as would have been
more » ... expected in case of a systematic timing difference. The results are consistent, however, with the presence of small known random synchronisation offsets within PACS.