Date: Tue, 9 May 2006 08:54:54 -0700 (PDT)
From: Spitzer Science Center Helpdesk <help@spitzer.caltech.edu>
Subject: New IRS LL fluxcon table


The last release of SPICE (v1.3 beta-1) provided those working
with IRS data the capability to apply an extended source calibration.
For extended source calibration of IRS low-resolution spectra, data are
extracted from 28-pixel apertures, after which both aperture and slit loss
corrections are applied.  We have recently found a minor error in the
b2_aploss_fluxcon.tbl file which causes the first order of Long-Low (LL1)
to be higher by 5--10% compared to the second order of Long-Low (LL2).
A new fluxcon table that fixes this problem is now available.  Those
wishing to apply the extended source calibration to LL1 data should
use the auto-update feature of SPICE to update the cal files after
Tuesday May 9, 2006.

The auto-update feature works by going into SPICE, selecting Update,
Select Refresh list, check on IRS Calibration Files S13.0, Click Update Now.
Wait for a couple of minutes.  The b2_aploss_fluxcon.tbl in the C13.0 and
C13.0PRE25 directories under spice/irs/cal should have the last line of the
comment field read "3.3 Apr 24/06".

Observers and archive users are strongly encouraged to enroll in the
moderated IRS interest group:

https://lists.ipac.caltech.edu/mailman/listinfo/irs-ig

Enrollment in this interest group will provide the most up-to-date
information on all aspects of IRS data.  It also provides a forum for
observers and archive users to exchange useful information amongst
themselves.

Spitzer Science User Support