Subject: JEM-X Monday Meeting 2006-02-28

Participants: SB, CBJ, NL, JC, NJW.

JEM-X status: New hotspot around (160,60) (raw coordinates) with
intensity up to 5 cts/s sometimes but generally much lower.
Other hotspots have only weak or no activity.

SB presented the gain development curve showing the high value
around the Earth observation and the lower level upon the
recent HV reduction.

The FRSS sources show the radioactive half-life, but there will
be enough counts until 2010 because the spectra can be integrated
over a longer timescale than the 4 minutes used currently.
The Fe55 sources last longer than the Cd sources.

The bug in the on-board time assignment that gives bad times when
a wrap around occurs about every 6 days. If there is data in the
buffer of the DPE i.e. in the presence of a strong source the times
given to the events can be wrong. This
resulted in what looked like a burst. The timestamps
can be repaired. In total there has been problems in about 30
cases (15 per instrument). About 200 packets could be lost
corresponding to 300 s of data taking. We must check what
happens with the ISDC processed data (JC will take action).

Earth observation (CBJ): The DXB spectrum derived from the
difference between looking directly on the Earth and when
the Earth is outside the FOV gives a factor 1.5 higher value
than the HEAO measurement. The method has been supported by
analysing the Crab spectrum in revol. 365 the same way.

There is still a question of scattered X rays from the
collimator.

ISDC consortium meeting (NJW): report.

SDAST meeting - no actions right now.

TEST format (SB): ISDC will FITS wrap the data in TEST
format. No decoding should take place because there are
cases where deconding is impossible. Contact person:
Nicolas Produit.

Where does other 'strange' data go such as 'On Request
Housekeeping' that belongs to science data?
The script that should treat this had not been activated
which means that some data might be missing or hard to
dig out for the period (beginning of 2003) where no
science data were transmitted to the JEM-X instrument station. 

Crab calibration (NL): ISDC has asked for certain off-axis
observations for NOMEX measurements and there are other
requests. Hence PK asked for reduced observation times
and we accept a reduction from 10 ks to 8 ks.

Moscow workshop (NL): We have to send abstracts by tomorrow.

Next INTEGRAL workshop 2008 in Copenhagen ? (NL): Chris Winkler
has sent out a request to us. How to react? We have to find a
place and the financing situation.

/NJW

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Niels J. Westergaard
Danish National Space Center
Juliane Maries Vej 30, DK 2100 Copenhagen O
Phone: +45 35325705; FAX:  +45 35362475