XMM-Newton Science Analysis System


oal (oal-3.126.1) [xmmsas_20160201_1833-15.0.0]

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SAS_OBT_MET_LINEAR

Setting this variable to a comma separated list of two numbers $slope,frac$ with $0<=frac<=1$ overrides any values given to SAS_OBT_MET_FIT. It enforces a linear relationship between OBT and MET with a slope of $slope$. For this only one data point from the Time Correlation File is needed. The point taken is $N\times frac$ with $N$ being the total number of points available, e.g. $frac=0$ selects the first, $frac=1$ the last point.

Caution: Please alter the above parameters via SAS_OBT_MET_LINEAR only when you exactly know what you are doing. Out-of-range conditions are caught but improper values can lead to inaccurate event arrival times.