EPIC BG working group: 8th meeting: 30/03/09 – Mallorca

1. EPIC BG working group: 8th meeting: 30/03/09 – Mallorca Location : Hotel Delfin Mar, Santa Ponsa, Mallorca Agenda ~15:00 - ~18:00 [Minutes - IdC] • Introduction and action items from last meeting [AR] • The status of the Blank Sky files and software [JC] • The EPIC-MOS background [KK] • Integrating ESAS into SAS [CG] • SOC view of the FWC data [IdC] • Discussion: Web Pages, BG Components, FWC data, new scripts/tools, long-term BG trends etc. [AR + all] • Summing-up - AOB - Plans for the next period - Next meeting

2. Apologies: MJF SS

3. Open Action Items from Minutes (1/2)‏ • AI_EPIC_BG_WG_01_12: on MF: Once any BG or Closed fits files had been obtained, the user can change their CCF_PATH etc. setup so that a new cifbuild would incorporate these extra files. This enables the BG/Closed events files (e.g. the ones used in SS's task) to be used in the SAS, without them having to be included in the CCF files. - ONGOING - Interface TBD (MF & RS)‏ • AI_EPIC_BG_WG_03_07: on ME: test soft proton screening s/w SAS tool .espfilt. v0.8.2 available in SAS 7.1: MOS & pn data looks OK, some plotting range adjustments needed . 4/5th CLOSED ? • AI_EPIC_BG_WG_03_08: on MF: UHB update section 3.2.4: outside FoV eff. area (up to 80 arcmin), Update of CCF (currently not supported, calview, 15 arcmin, TBC) OPEN . provide numbers from simulations by B. Aschenbach • AI_EPIC_BG_WG_03_10: on SM: provide BGWG with script on bkg treatment in spectral analysis (after publication of related paper) . OPEN • AI_EPIC_BG_WG_03_11: on AR: check HK parameters for anomalous MOS FWC data - ONGOING • AI_EPIC_BG_WG_04_02: on SS/K. Kuntz: try to extend MOS tools such that they also work for EPIC-pn by about June 2007 . ONGOING • AI_EPIC_BG_WG_04_08: on AR: trigger the generation of smaller sub-sets of EPIC-pn FWC data (with M. Freyberg) update of FWC web page needed . OPEN - ONGOING

4. Open Action Items from Minutes (2/2)‏ • AI_EPIC_BG_WG_06_01: On SS/KK: After reception of more 10 ksec FWC data, re-discuss observing strategy: is it useful to collect FWC at start/end of orbit or during slew observations? – OPEN - discuss • AI_EPIC_BG_WG_06_03: On SS/ME: release of a new ESAS (MOS only) version updated for SAS v7.1 - OPEN/ONGOING ? • AI_EPIC_BG_WG_06_05: On WP: ask M. Bauer about the possibility to convert the new BG handling method into a script/tool for general usage - OPEN (to be released as web page?) CLOSED – web page • AI_EPIC_BG_WG_06_06: On WP: ask M. Bauer to compare the new method with the principal method used by XMM-ESAS, i.e. not subtracting but modelling of the background; SS is interested to help when files are available from M. Bauer – OPEN - CLOSED – M. Bauer left astronomy • AI_EPIC_BG_WG_06_07: On SM: to provide new threshold numbers for the Fin/Fout tool to AR to allow him another update of that script (specifically to account for the MOS1 CCD6 loss) . OPEN

5. New Action Items from Minutes • AI_EPIC_BG_WG_07_01 On JC: to provide ME with a list on major performed updates on blank sky files (as input for next UG meeting report) CLOSED • AI_EPIC_BG_WG_07_02 On ME: to draft next UG presentation and distribute to AR/SS for check and comments CLOSED • AI_EPIC_BG_WG_07_03 On JC: to draft a section on the release of BGSelector for an XMM-Newton Newsletter CLOSED • AI_EPIC_BG_WG_07_04 On JC: to provide descriptions of limitations of refilled blank-sky event files on the blank sky web page (Watchout section) and continue investigation of possible solutions to ghosting problem CLOSED • AI_EPIC_BG_WG_07_05 On JC: to provide descriptions on the scaling of exposure maps and on the workaround for the skycast problem (both related to blank sky fields) on the blank sky web pageCLOSED • AI_EPIC_BG_WG_07_06 On JC & AR: to include descriptions mentioned under AI_WG_07_05 also in related scripts and tools CLOSED • AI_EPIC_BG_WG_07_07 On CG & IC: to check BGWG pages from a users point of view and to provide ideas for further improvement of the documentation-? • AI_EPIC_BG_WG_07_08 On CG & IC: to consider preparation of simple analysis threads and recipes for the analysis of extended sources (mentioning complexity & different approaches) -? • AI_EPIC_BG_WG_07_09 On CG: clarify (with R. Saxton) arfgen problem reported by S. Snowden which is related to the planned ESAS update -?

7. Changes to the Web Pages

9. Changes to the Web Pages

11. Changes to the Web Pages

13. Changes to the Web Pages

14. Changes to BGWG FWC Files • Users reported problems using BGWG FWC datasets in sky co-ordinates (`corrupted` X/Y co-ordinates)‏ • Sky X/Y co-ordinates are meaningless (events collected from different pointings, and are in FWC mode anyway) • Suggested (AR) fix to users: Skycast (i.e. attcalc) FWC file to fixed point in the sky • To prevent re-occurrences, all the pn and MOS BGWG FWC datasets have been skycast to RA=0, Dec=0, PA=0 (IdC)‏ • These files have been checked (AR, IdC) and now replace the older files on the BGWG web pages

15. EPIC FWC Closed Observations in the RCP • Needed to look at reducing FWC observation time • Current situation: 12x10 ks per year in FWC • 1st proposal: Reduce to 2x10 ks per year in FWC • pn OK - instrumental BG appears quite stable, but MOSs show some instrumental BG variability - every 6 months is too sparse • Current proposal: 2x10 ks per year in FWC, plus every 4th MOS slew in FWC (other 3 of 4 MOS slews in CAL CLOSED, [pn slews used for science])‏ • This is not a problem for OPS • Current proposal is acceptable by MOS and pn BG teams

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17. ME – Maria is asking about the long term planning for the filter wheel closed observations that we have introduced first as NRCO and now as routineEPIC calibration: There are several questions: - for how long will these dedicated observations be needed? • can they be done at the end/start of an orbit where there is a higher risk of radiation? I understand for this you first need to look into the recently collected data to see if there is a difference between observations done in different parts of the orbit - did you already find the time to look into these observations? • Question to pn:- is there a possibility to merge shorter extended full frame mode closed filter exposures to reach your calibration goals? The reason for asking is that currently the dedicated observations are rather long due to the very long instrument overhead time of this pn readout mode. If shorter & merged observations are fine for you as well, this could significantly reduce the time needed for these now routine cal observations.

18. MF – I had not attended the relevant meeting when the NRCO had been discussed and initiated. So I cannot answer this for EPIC-pn(I guess MOS had been the driver for this). For EPIC-pn the main goal is to monitor the high-energy particle background (intensity, spectrum, spatial) induced in the camera. Therefore representative measurements are desired, i.e. Conditions during the FILTER=CLOSED exposures similar to those in guest observe observations. EPIC-pn has always used parasitically other calibration observations for FILTER=CLOSED set-up (in various instrument modes)for this purpose, preferentially in the middle of an orbit. Soft proton flares do not affect the goal of these FILTER=CLOSED exposures, however, radiation at the start/end of an orbit may doso (e.g. change in intensity of camera background).At the very highest levels also the spectrum may change. One idea at the EPIC-Cal (actually BGWG) Meeting was to add a new extension to EPIC-pn event files with the discarded column counter lightcurve as a particle background monitor. This, however, had increased the memory needed in the SAS task "epframes" which already(sometimes) is causing trouble in the case of very long and/or very bright observations (and would also increae the size of the final event file). Therefore instead a seperate lightcurve file is being created if a user switches on this behaviour. This is currently tested(new task versions of "epframes" and "epchain"), but no output in terms of event files and background dependencies on orbital phases have been analyzed yet (sorry). Concerning merging eFF-Mode exposures: my proposal were to change the "long-exposure set-up" (AB Dor ?) from FF-Mode to eFF-Mode (always),and to do these shorter exposures always in FF-Mode instead, to minimize the total amount of overhead. One problem recently arose when RGS calibration observations that were previously used for CalClosed or Closed filter set-up, have now been split into 5 individual (but consecutive) observations, causing 5-times the PN overhead (e.g. forMkn 421). Addtionally, it had been requested to have one of these observations in an EPIC "scientific" filter position, however, for PN only Timing-Mode is meaningful for Mkn421 in any non-closed filter(I guess RGS want to have positional information as they are doing small shifts of 30 arcsec or so between the observations). So PN is losing a significant amount of possible and previously used calibration time now. Is it possible to have at least just one long PN exposure after the one "scientific" as requested by RGS ? (I assume that a formally new observation requires also a new offset map etc. if not scheduled otherwise - for FILTER=CLOSED, however, a small attitude shift does not harm at all for EPIC-pn).

19. ME – I am contacting you as the XMM-Newton User Group is preparing their next meeting (May 6-7) and asking again about a report of the Background WG. I understand from Andy that most members of the BGWG (except I guess Andy/Jenny/myself and two newcomers from ESAC - Carlos Gabriel, Ignacio de la Calle) will not be coming to Mallorca this time. So to kick start the discussion, I'd like to list some ideas/topics I could present in May on behalf of BGWG:- Adding more data: - FWC: we are performing now routine cal observations -> what is happening to the data; anybody using them? Any updates for pn & MOS files? Do we have to continue with this routine cal ? - Blank-sky files: what happened in between? Any new files/modes added? I remember the ghosting script issue... and the BGSelector • announced (at UG meeting) ?images? script was released • What about ESAS for pn? update for MOS after SAS release happened Long term goal: ESAS as a SAS task - is this still envisaged? espfilt (MOS only) made it into SAS; further plans? Even if there might not be much progress, I would appreciate if Steve could provide me with input on the status & plans- the residual Soft Proton flare contamination script was updated- ??? • Do you think that in time for the UG meeting we will have anything exciting to be added here?

20. SS – ESAS - AI_EPIC_BG_WG_04_02 It has been a very frustrating last few months on the XMM-ESAS front. Every time that I've been able to work on it some else has broken. I've made no progress on the pn as I'm still trying to get XMM-ESAS to work well with SAS 7.1.2. The 100 ks SWCX observation which I was able to process before now dies when I try and create an exposure map for the MOS1 data. It dies with: ** eexpmap: warning (NoOffset), Extension OFFSET not found DEALLOCATE failure: ALLOCATABLE array is not ALLOCATEd Program terminated by fatal error Abort This is a show-stopper for this observation and I have Brendan trying to find what is happening. I've processed another observation without the problem and eexpmap seems to work fine for the MOS2 data in the SWCX observation. Another area where there is potentially a real problem is with arfgen and the creation of the cross-arfs. I've been in touch with Richard about this. The problem is that the normalization of the arf changes with selected binning size for the detector map. Not a good thing. I've been holding off on a new release of ESAS until this gets resolved. SS – 270308 – Kip uses the closed filter data when he updates the data files for XMM-ESAS. I’ll have to do another update soon which should show the utility of the cal observations.

21. Fin_over_Fout [New – Available] Warnings put in regarding use of the MOS1 algorithm with post Rev-961 MOS1 CCD6 loss [have requested input from SM/AL]