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16 May 2003 

Present  : JRL, STH, MJI, PSB, DWE

Agenda
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1.  Actions from last meeting
2.  Photometric calibration plans
3.  Model data for tests: catalogue and pipeline
4.  Report on AA, SJW and DWE meeting
5.  Discussion of what we need to prepare for June UKIDSS meeting
6.  Status of e-science II bid
7.  AOB

Minutes
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1.  Actions from last meeting

STH  is producing a document on photometric calibration plans (see item 2).
DWE  contacted Ian Bond regarding his difference imaging software. This
     has not arrived yet. Will pursue.                                     <<<<
MJI  found that the mosaicing requirements are for producing tiles,
     possibly with adjacent coverage (but definitely not half the sky).
JRL  has come up with a solution to naming uniquely the master 
     calibration files using a nightly rootname basis with appended 
     MSB-related naming if needed.
STH  has looked at the ESO naming conventions for issued documents and 
     summarised his understanding of it as:
     Project-DocumentType-Source-WorkPackageNo-NumberWithinWPN
     The first three are 3 letters and the last two are 4 digits.
     Project should be VDF, Source should be IOA rather than CAS,
     STH will be the Document Wrangler in charge of the numbering.
PSB  has proceeded with the VDFS PDR documentation using vista_ocdd10 and
     vista_srd_v20 for the science and user requirements.  These are 
     probably adequate for the PDR but both need urgently reviewing
     (particularly srd_v20) for the FDR.  MJI will remind JPE and WJS
     of the need to revisit these issues.                                  <<<<
JRL  have tested the effect of lossy Rice compression on parameter
MJI  estimation from real*4 data. There is negligible effect on 
     catalogue parameters.  Processing INT WFC data as real -v- integer
     through the pipeline gave bigger differences.  More tests on the 
     randomness of the noise are needed. PSB suggested testing stacked
     compressed data to look for subtle effects.                           <<<<
ALL  have sent comments re. Observing Strategy meeting to MJI who 
     contacted Mark Casali, who revised the schedule (also see item 5)
JRL  has carried out tests on J-band twilight sky flats. The 10K-30K counts
     needed can be obtained in a 2-2.5 minute window.  We still need
     H and K flats - AA has promised these - and to compare dark sky flats 
     with the twilight ones.                                               <<<<
PSB  contacted our usual local supplier re. Ultrium tape systems. 
     Progressing this issue is on hold until we see exactly what make
     of Ultrium drive JAC buy. 
MJI  contacted NCH to see if we can get a quote from their supplier
     and got the necessary contact details.
MJI  is still trying to acquire the 2MASS data.  Lack of DLT tapes at CDS 
     is the holdup excuse !                                                <<<<
DWE  placed the DR1/UKIDSS plots on web and sent them to SJW.
DWE  attended a meeting with SJW and AA to discuss survey planning (see item 4)
DWE  reorganized the internal directory structure
STH  are continually revising the WP spreadsheets
MJI 


2.  Photometric calibration plans

STH reported that a preliminary document has been written, taking over from
where NCH left off. On June 6th there will be a meeting between SJW, PCH
(chair of calibration WG) and STH where all calibration aspects will be 
discussed. JRL and/or MJI should also attend this meeting.

The next CASU meeting will be on Tuesday 3rd June so that some further 
discussion on this document can take place before the meeting on the 6th.
[MJI is away observing/confererence from 20th-31st]

The calibration WG have reached the following conclusions:
* UKIRT faint standards should be the primary calibrators
* secondary standard fields need to be set up using WFCAM
* no point in setting up secondary fields using UFTI or UIST 
* mesostepping will be used to assess the uniformity of the calibration
* 2MASS data will only be used for monitoring throughput (+/-10% level)

Although there was no requirement to observe standards with UFTI, STH still
wanted to use the service night that was on offer.                         <<<<

Secondary fields centres need selecting. They would be selected before 
the survey start using 2MASS as an aid in decision making, and would be 
built up during the survey.

STH should finish off the document by the next meeting so that we can
discuss this before the meeting on the 6th.                                <<<<


3.  Model data for tests: catalogue and pipeline

Simulated data is required for a number of tests of (mainly 2D processing
throughput and accuracy).  After some discussion it was decided to use 
2kx2k chunks x4 of INT WFC data degraded to WFCAM noise characteristics 
and with WFCAM-style FITS headers added.  This is a lot simpler than doing 
a full simulation. JRL will generate some pseudo MSBs of data.             <<<<

Further downstream we will need model simulations for more thorough tests
of the catalogue parameter generation software.  Several groups have done
this sort of task, so reusing their model generation sofware is the goal.


4.  Report on AA, SJW and DWE meeting

DWE reported on a meeting he had with SJW and AA. His notes on this meeting
are in the internal directory.

Considering the work that had already been done by SJW and AA it was felt
that it was not necessary for DWE to carry out simulations of his own on the
observing strategy and survey completion. AA said that due to the link
between the Query Tool and any simulations, the best place for any further
simulations would be at JAC. DWE agreed with this.

There is a new plan regarding the survey manager. This will now be 2 x 0.5
posts. One based at JAC and the other in the UK (presumed CASU or WFAU). 
This was news to MJI. He will contact AA about this.                       <<<<

There still seemed to be differing opinions (between JAC and CASU) as to 
what constituted an MSB. JRL said that photometric calibrations need not
be included in an MSB (but could be). The main point was that an MSB 
should contain enough data to remove the instrumental signature.

Concerns were expressed about the QT by STH and MJI. They wanted to know
a lot more detail about it. These will be raised with AA at the Edinburgh
meeting.

STH queried the comment regarding the high sky values for J (not H) at
sunset. Plots were shown (from the UKIRT web site) to show that this was 
the case.

One of the main points of the meeting was for SJW to form sensible questions 
to ask the survey heads so that the survey definitions could be finalized.


5.  Discussion of what we need to prepare for June UKIDSS meeting

Various reports were being prepared for the meeting.  We will discuss the
contents for our presentations at the next CASU meeting on 3rd June 
focussing on:

Standard fields (+ presumably calibration plans) STH
QA pipeline processing  MJI,JRL
Unreslved data processing issues   MJI,JRL

JRL will deal with booking a hotel.  DWE will investigate flight options.  <<<<


6.  Status of e-science II bid

An e-science bid is being put in for the end of the month (NAW is
organizing this). This will be for 2+ years after the current 2 years
of VDFS funding ie. to 2007 (~1 year after VISTA commissioning). This 
is supposed to be a joined-up roadmap bid aka VISTA-Eddington(WASP)-GAIA
in order to maximise synergies and minimize management overheads.


7.  AOB.

MJI commented on the VDFS management team meeting.  Prior to the 1st meeting
there was some confusion about exactly what was required for monthly reports 
for these meetings.  This has now been resolved.

PSB and JRL had a quick look at the Astrowise documents, but found
it difficult to get anything out of them. They are in PowerPoint which does
not show up the detail. STH will see if he can get better versions of these
documents (or the proceedings).                                            <<<<

=============================================================================

Continuing actions
------------------

DWE  obtain Ian Bond's difference imaging software 

MJI  acquire 2MASS data.

New actions
------------

MJI  remind JRE/WJS about need for updating science/user requirements 
     documents for VISTA

MJI  carry on with Rice compression tests: randomness of the noise 
JRL  and stacking tests

JRL  remind AA about need to aquire H and K twilight flats and compare
     dark sky flats with the twilight ones

MJI  progress acquiring 2MASS data

STH  contact AA about UKIRT service night for standards observations

STH  finish off the draft of the photometry document by the next meeting 
     so that it can be discussed before the meeting on the 6th.

JRL  produce simulated data (using WFC data and degrading it to WFCAM
     characteristics but with WFCAM-style FITS headers). 

MJI  contact AA regarding new plan for survey manager (2 x 0.5 posts).

JRL  look into booking a hotel for us for Edinburgh meeting

DWE  check up on our flight options for Edinburgh meeting

STH  get better version of Astrowise documents if possible