16 May 2003 Present : JRL, STH, MJI, PSB, DWE Agenda ------ 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 ------- 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