Reference detector pixels out of range when slewing

[bwgref]

User issue.

Occasionally the beginning of an observation can include a slew period, which causes the reference sky pixels to be out of range.

This was found for 30 Dor C, which I think is in the CVZ. Usually NuSTAR arrives in earthshadow so it doesn't matter if the slew timing in the observation (which is inserted by hand) and actual timing of the slew is off by a little bit. However, since we arrived while the source was "on", it look like the reference image puts the field of view outside of the 1000x1000 (about 40x40 arcminutes) allowed sky image.

This is a pretty rare occurrence, but should be probably be caught anyways when the projected image is outside of the nominal 1000x1000 grid.

Work around is to remove the slew period at the start of the observation by hand using a usrgti file.

[bwgref]

Note to me: The SOC should probably routinely check to make sure that the source isn't slewing at the start of the observation.

[XiaonaS]

Hi Dr. Grefenstette,
I try to use the obsid "50002031004" which is used in your walkthrough, there's still the same problem:
% Compiled module: MRD_STRUCT.
% Attempt to subscript INSTRMAP with II is out of range.
% Execution halted at: NUSKYBGD_INSTRMAP 127
/home/sun/AnalysisTools/nuskybgd/pro/nuskybgd_instrmap.pro
% $MAIN$

Don't you have the same problem?

You said:
"Work around is to remove the slew period at the start of the observation by hand using a usrgti file"
I am not very clear the data form, and could you please tell me how to check the "slew period" and remove them in detail? in which file(s)?
Looking forward to you reply!
Thank you!