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2.10 Caveats applicable to OLP versions prior to V6.1


Observers who received OLP V6.0 data should note that their data was reduced with versions of Cal-G 13 and 25_x derived with software inconsistent with OLP V6.0. This is discussed further in section 8.6.

Observers who received OLP V5 data should be aware of a concern relating to the flux calibration of AOT06 and AOT07 after some bugs were found in the AA pipeline stage. A bug exists in the module that handles reference scan   data, which then affects the flux calibration of AOT06 and AOT07 grating part data. The net result is that the fluxes in such AARs have been multiplied by an unknown factor. In long AOT06s several parts with reference scans are contained which can go wrong by a different factor. As the software currently interpolates between these reference scans, also the shape of the final spectrum can be wrong. In many cases these factors are of order 1. However, on occasion it can be of the order of thousands, or any value in-between. Because of this reference scanning has been disabled for OLP V6 onwards.

Because of bugs in two pipeline flux calibration modules FP fluxes are also wrong. As the effects of the two bugs can add up or cancel out, factors close to one but also factors 2-3 can occur.

These concerns affect the AAR product of OLP V5, not the SPD.

K. Leech with contributions from
the SWS Instrument Dedicated Team (SIDT)
and the SWS Instrument Support Team (SIST)