Subject: JEMX Monday Meeting 2005-10-24

2005-10-24
Present: SB, JC, NL, CAO, CBJ, NJW

Status for JEM-X instruments (NL): JMX2 was switched on 2005-10-21
            with a temperature rise as a consequence.
            Also the JMX1 temperature went up by about 8 degrees -
            larger than usual possibly because the
            pointing direction also changed by a large angle at the
            same time. The gain increases by 2%
            per degreeC. Hence the temperature dependence is stronger
            than in the beginning of the mission.
            The OMC flat field with JEMX HV exercises will happen
            tomorrow (2005-10-25) using TEST format
            (tested during Crab calibration in revol 365 and proved
            to work).

            Electronic calibration (CAO): An alert was recently
            issued but the deviation from linearity
            is not severe and the limits given in IMOD will be
            updated with the next delivery.
            This is about amplifiers #5 and #15 in both detectors but
            these are placed in an electronically
            'bad' position.

            Hot spot (CBJ): The activity is at a very low level.
            Ambient radiation is at a low level as well.
            (CAO): Hot spot analysis should be done per science
            window (in stead of per 100 000 events) in
            order to make it easier to assess the loss of area.

Results from Crab calibration (NJW): Download initiated; analysis
            will start soon. (CBJ): Looks OK.

Alignment studies (CBJ): One year of IPF data. 2000 sources detected.
            The RA scatter plot as a function
            of significance shows no improvement after a certain
            significance. This indicates that there
            is a systematic error. A neural network analysis has been
            tried but more tests are needed
            - could there be a temperature effect or solar aspect
            angle? Time since last eclipse?
            (NL): A search for the imprecise localisation has so far
            not given concrete results.

Other (NL): Light curve extraction works from rev_2 data reading PI
            values.

ISDC consortium meeting and ISWT meeting (NL): The pressure in JEM-X
            software is increasing.
            Core program for next AO will aim at filling out the
            under-exposed regions of the galaxy.
            Keyprojects will be defined for the longer timescale. An
            Earth observation will be tried
            to remove the CXB from the (or a large fraction) ISGRI
            FOV, hence completely from the
            JEM-X FOV.

OSA 5.1 status (NL, NJW): Release some time in the end of the week.

Science results (NL): GRS 1915 observed. XTE J1739 bursts (SB):
            Activity continues. (JC): GX 3+1
            interesting burst. (NJW) TO has made Cas A analysis with
            spectral lines.

AOB:        Discussion about the gain calibration reorganisation and
            a JEM-X consortium meeting.

/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