Document Number:   WFC-CAS-WPS-00000-00030 
Document Title:   End of Month Report Aug 05 
Document Authors:  Mike Irwin, Simon Hodgkin 
Document Issue:  1 
Document Date:  5/9/2005 
 
This document presents work package progress by CASU during August
2005.  For further details of group activities over the past month and
quarter see http://www.ast.cam.ac.uk/vdfs/diary.html. For the minutes
of all group meetings see http://www.ast.cam.ac.uk/vdfs/docs/minutes
 
Science Verification and interaction with UKIDSS 
 
CASU attended the UKIDSS SciVer meeting held at ROE this month. Talks
were presented by MJI (pipeline processing), MR (flatfields, CASU WWW
pages), STH (photometric calibration) and EGS (internal SciVer:
stacking, completeness). See
http://www.ast.cam.ac.uk/~wfcam/docs/reports/sv/ and
http://apm15.ast.cam.ac.uk/casudoc/wfcam/science-verification for
details. All presentations have been placed on our www pages for
internal/external access.
 
There was good interaction and feedback from the UKIDSS Testers
community. The following suggestions have been taken on board:

1. The discussion of catalogue parameters has been extended (with
emphasis on classification and fluxes), see
http://www.ast.cam.ac.uk/vdfs/docs/newparams4.pdf

2. The summary/status pages now include inline images as well as
postscript files

3. A page of known bugs and features with the data has been started
(not yet complete/available)
 
The next SciVer meeting will be held at the IoA on September 21st. STH
and Paul Hewett are also hosting a WFCAM calibration workshop on
September 20th. STH will circulate a document discussing his findings
with the calibration of WFCAM data in good time for this meeting.
 
WFCAM processing status 
 
The new photometric calibration has now been applied to all data up to
and including 19th April (SV1). These new catalogues also include a
revised parameter set: 
	1. new magnitudes (Petrosian, Kron, Hall)
	2. errors on the measured quantities 
	3. the larger apertures have been rescaled to be smaller (the
	largest has been shrunk from 64 to 24 arcsecs). 
 
Reprocessing has been carried out on all data affected by the pipeline
software stacking bug.  Also all the SV data up to and including 19th
April (SV1) has been reprocessed with the new catalogue generator in
order to calculate the new parameters, errors etc..  We were all asked
to examine this new data for problems prior to releasing it and prior
to finishing off the rest of the 05A data catalogue (re)generation.
 
A prototype crosstalk-removing algorithm has been written by MJI, and
is in the middle of testing.  At this stage it is unclear if it is
worth reprocessing all the 05A data again to incorporate this.  MJI,
after discussions with NCH, recommended using it in anger on 05B data
and then re-assessing the situation re: 05A data further downstream.
The main reason is to limit the long-term number of available
reprocessed versions of the same data.
 
Two new disc servers (8 TBytes each) have been ordered. A new rack
will also be ordered shortly to locate some of the disk server kit
more appropriately.
 
JAC Telecons 
 
The main item discussed was how far the requirements of the summit
pipeline have been met, particularly with respect to its speed.
 
WFCAM is currently on the telescope and working. An automated guide
star acquisition system is now in place. Fine-tuning of the optics has
been carried out to sort out tilt etc. Images were found to be 0.65"
on all chips (Gemini reported 0.5" images in V on the same night) on
the 1st night of on-sky tests. The field lens has been cleaned so that
the worst of the scattered light/thermal emission problems (the
"crud") has been eliminated.
 
Some redesigning of the UKIDSS WFCAM survey MSBs has been done to help
improve the observing efficiency whilst maintaining the science
return.  The primary result from this should be a significant
reduction in the nightly raw data rate.
 
Status of VDFS 
 
The latest version of the ETC including the revised C code has been
circulated to JPE, MJS and MJI for comment. The other docs have been
signed locally and are ready to distribute for signatures.