New STIS Target Acquisition Checking Procedure
As of May 9th, manual reviews of STIS target acquisitions
are no longer being performed on a daily basis. From now on,
STIS ACQ and ACQ/PEAK data will be reviewed once a month.
PIs of STIS GO programs (or their designated contact
persons) should receive a warning by email at that time, if
there appear to be problems with the acquisition.
Note, however, that the ultimate responsibility to check
STIS target acquisitions lies with the PIs, not with STScI.
The software which is used to evaluate the target
acquisition data, IRAF/STSDAS task "tastis" in the
stsdas.hst_calib.stis package, is available to observers.
This program reports the location of the peak flux in each
acquisition image, and the size of the telescope offset that
was needed to center the target. It issues a warning if the
fluxes of the apparent target measured at different stages
within the ACQ or ACQ/PEAK are inconsistent, or if an
unusually large telescope offset was needed in the final
centering stage of the ACQ. Anomalies in the flux
distribution encountered in the ACQ/PEAK sequence are also
reported. The program is described in more detail in the
help file of the "tastis" task.
The STIS target acquisition procedure is described in
Chapter 8 of the STIS Instrument Handbook. The acquisition
data products and the information that they contain are
presented in section 5.7 of the HST Data Handbook for STIS.
Both Handbooks are available through the STIS instrument
webpage at
http://www.stsci.edu/hst/stis.
Note that observers have 90 days after delivery of their HST
data to request any repeats for failed observations.
This is done by filing a Hubble Observation Problem Report
through the web at
http://www.stsci.edu/hst/Post-observation/reporting_problems.
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