Subject: JEM-X Monday Meeting 2006-11-13

NB: New version: Corrected with regard to the flux
extraction results by JC.



Participants: NL, JC, CAO, NJW.

JEM-X status (JC): Anodes have no development since last
week. Gain of last revolution quite smooth.

OSA6 (NJW): j_ima_iros-1.7.0 has been delivered.
j_ima_shadowgram-2.1.0 has struck an obstacle regarding
the test data. Mark Gaber looks into it.
SPR 4594 demanding all images to be produced has been
fulfilled with this delivery. As an example the Crab
appears (faintly, but still) when 60 events are used for
imaging. j_ima_mosaic-6.0.4 has been delivered.
Only small changes. The change of units (to cts/dm2/s)
implemented for j_ima_mosaic but not for j_ima_iros.

The case of 036500810010 with nominal 700 s of data but
really there are only 46 s of data present. Where does
this come from and how is this situation flagged?

Flux extraction (JC): The three imaging flux extraction
methods (summing 7x7 pixels, mosaic_spec, or
SRCL-RES(from j_ima_iros)) give an increase of flux when
the off-axis angle increases when this is larger than
3 degrees.
For j_ima_mosaic the effect is less pronounced (since
'off-axis' is ill defined).
The use of mosaic_spec gives more consistent results but it
is very important to use the correct parameters (e.g. the
default PSF with is 7 arcmin for ISGRI). Instrument
related default parameters could be an asset for this
program.

We recommend the use of mosaic_spec as the baseline
spectral extraction.

Calibration data (CAO): If the HK parameter DFEE_STATUS is
not set to data-taking in a 4-minute interval then several
HK partitions containing the calibration data will be
ignored by ISDC Preprocessing. At the beginning and end of
revolutions this can lead to the loss of useable events
because they lack any gain history data. CAO is in contact
with Nicholas Morrisset from ISDC and he will change
Preprocessing so that it unpacks all the calibration
data in future, regardless of the value of DFEE_STATUS
recorded in the partitions.


/NJW