Atacama Pathfinder EXperiment APEX
SABOCA Calibration
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Array parameters July 2009 (03/07-07/07)

SABOCA was cold and in use between 3rd and 7th of July.

Because of the mounting of SABOCA in the Cassegrain cabin of APEX and the very exposed position of its mirrors, the optical path was seriously affected by some imperfections in the mirror mounting. This leads to a very elliptical beam shape, with a beam size much larger than expected.
A proper data handling would probably try to reduce the channels individually and smooth to a common beam before combining the individual channels, in order to obtain a proper flux calibration.
The mirror mounting problems were later identified and fixed before the September 2009 SABOCA observing run started.

Main parameter file: saboca-2009-07.rcp

Individual scans

Scan #Date Parameter fileArray plotIndividual channel maps
38436 2009-07-03T11:51 Mars_38436_Saboca.rcp array_38436.pdf beams_38436.pdf
38437 2009-07-03T11:59 Mars_38437_Saboca.rcp array_38437.pdf beams_38437.pdf
38785 2009-07-04T13:01 Mars_38785_Saboca.rcp array_38785.pdf beams_38785.pdf

Notes on individual channels

All 37 channels of SABOCA are working fine. Between March 2009 and March 2010, all backend signals are inverted, which has to be taken care of during data reduction:

# Handle inverted channels (all):
data.Data *= array(-1,'f')