PACS Status Report Herschel ST#38ESAC, 30 Jun 2009 Herschel map making workshop 10 July 2009 B.Altieri/E. Sturm for the PACS Team / HSC Herschel map making workshop 10 July 2009 B.Altieri/E. Sturm for the PACS Team / HSC

2 PACS Status Report IAS map making workshopIAS, 10 July 2009 Overview Instrument Commissioning and Performance Verification Phase Calendar PACS Instrument Status to Date –Mechanisms –Detectors –Optics/PSF/Focus Photometer data processing status

3 PACS Status Report Herschel/PACS Commissioning DateODActivities So, Mai 24, 0911PACS switch on, SFT Mo, Mai 25, 0912 Di, Mai 26, 0913 Mi, Mai 27, 0914 Do, Mai 28, 0915 Fr, Mai 29, 0916Grating tuning - 1 Sa, Mai 30, 0917 So, Mai 31, 0918Grating tuning - 2 Mo, Jun 1, 0919Grating tuning - 3 Di, Jun 2, 0920Chopper stability - 1 Mi, Jun 3, 0921Grating tuning - 4 Do, Jun 4, 0922Chopper tuning -2 Fr, Jun 5, 0923 Sa, Jun 6, 0924 So, Jun 7, 0925 Mo, Jun 8, 0926FFT + dark measurement Di, Jun 9, 0927Chopper tuning (MTL) - 5, SPT SPEC, SPT PHOT, Bolo bias=0 Mi, Jun 10, 0928Ge:Ga bias - 1, part 1 Do, Jun 11, 0929Ge:Ga bias - 1, part 2 Fr, Jun 12, 0930 IAS map making workshopIAS, 10 July 2009

4 PACS Status Report Herschel/PACS Commissioning Sa, Jun 13, 0931end of OD: Cooler Recycling So, Jun 14, 0932Cryo cover open, Sneak Preview Mo, Jun 15, 0933Chopper tuning (MTL) - 6, Telescope background Di, Jun 16, 0934 Mi, Jun 17, 0935 Do, Jun 18, 0936Coarse Ge:Ga Bias, CS cooldown Fr, Jun 19, 0937Coarse Ge:Ga Bias (dark) Sa, Jun 20, 0938 Bolometer Biases for Pointing - 1 So, Jun 21, 0939 Mo, Jun 22, 0940 Di, Jun 23, 0941 Mi, Jun 24, 0942 Do, Jun 25, 0943Bolometer Biases for Pointing - 2, Coarse GeGa Bias Fr, Jun 26, 0944 Sa, Jun 27, 0945 So, Jun 28, 0946 Mo, Jun 29, 0947Coarse GeGa Bias (PACS CoP completed) Di, Jun 30, 0948SIAM Scan Search Mi, Jul 1, 0949 Do, Jul 2, 0950 Fr, Jul 3, 0951 Sa, Jul 4, 0952 So, Jul 5, 0953SIAM Updates & Check Mo, Jul 6, 0954 Di, Jul 7, 0955 Mi, Jul 8, 0956 Do, Jul 9, 0957 Fr, Jul 10, 0958 Sa, Jul 11, 0959 So, Jul 12, 0960 Mo, Jul 13, 0961 Di, Jul 14, 0962 Mi, Jul 15, 0963End of CoP IAS map making workshopIAS, 10 July 2009

5 PACS Status Report Herschel/PACS Performance Verification Do, Jul 16, 0964Start of PV Fr, Jul 17, 0965 Sa, Jul 18, 0966Cooler, Phot Setup, FPG So, Jul 19, 0967Spec Set Up, Spec flux Mo, Jul 20, 0968 Di, Jul 21, 0969 Mi, Jul 22, 0970 Do, Jul 23, 0971 Fr, Jul 24, 0972Cooler, Phot Setup, FPG Sa, Jul 25, 0973FPG, Spec Setup, Spec FPG So, Jul 26, 0974 Mo, Jul 27, 0975 Di, Jul 28, 0976 Mi, Jul 29, 0977 Do, Jul 30, 0978Cooler, Phot Setup, Bias (12xgreen) Fr, Jul 31, (8xgreen, 3xblue), PhotSpatial, SpecS Setup, FPG Sa, Aug 1, 0980 So, Aug 2, 0981 Mo, Aug 3, 0982 Di, Aug 4, 0983 Mi, Aug 5, 0984Cooler, Phot Setup, Bias (12xblue) Do, Aug 6, (5xblue), SpecS Setup, FPG, GeGa, IP, Flux Fr, Aug 7, 0986 Sa, Aug 8, 0987 So, Aug 9, 0988 Mo, Aug 10, 0989 Di, Aug 11, 0990Spec Setup, Flux, FPG, Wave Mi, Aug 12, 0991GeGa, IP, Wave, AOT, Spatial, FPG Do, Aug 13, 0992 Fr, Aug 14, 0993 Sa, Aug 15, 0994 So, Aug 16, 0995 Mo, Aug 17, 0996Flux, GeGa, IP, AOT Di, Aug 18, 0997Cooler, Bias, Flux Mi, Aug 19, 0998Bias, Spatial Do, Aug 20, 0999 Cooler, Bias, Flux, Spatial, Spec IP, Spec Flux, Spec AOT Fr, Aug 21, Sa, Aug 22, So, Aug 23, Mo, Aug 24, Di, Aug 25, 09104Cooler, Spatial, Bias, AOT, Flux Mi, Aug 26, 09105AOT, Flux Do, Aug 27, 09106Cooler, AOT, Flux Fr, Aug 28, 09107AOT, Flux, GeGa (1.2.3) Sa, Aug 29, So, Aug 30, Mo, Aug 31, 09110Flux, IP, Spatial, AOT Di, Sep 1, 09111Spatial, Flux, AOT Mi, Sep 2, 09112Cooler, AOT,Spatial, Flux Do, Sep 3, 09113Spatial, Flux, AOT Fr, Sep 4, Sa, Sep 5, So, Sep 6, Mo, Sep 7, Di, Sep 8, 09118Cooler, Spatial, AOT Mi, Sep 9, 09119Flux, Spatial, AOT Do, Sep 10, Fr, Sep 11, Sa, Sep 12, So, Sep 13, Mo, Sep 14, 09124Spatial, Flux, AOT Di, Sep 15, 09125AOT, Spatial, Flux Mi, Sep 16, Do, Sep 17, Fr, Sep 18, 09128Wave, AOT Sa, Sep 19, 09129AOT, Flux, Wave So, Sep 20, 09130Wave, Flux, AOT Mo, Sep 21, 09131Cooler, AOT, Flux Di, Sep 22, Mi, Sep 23, Do, Sep 24, 09134SPIRE/PACS parallel Fr, Sep 25, 09135SPIRE/PACS parallel Sa, Sep 26, So, Sep 27, Mo, Sep 28, 09138PACS TBD Di, Sep 29, 09139PACS TBD Mi, Sep 30, Do, Okt 1, Fr, Okt 2, 09142PACS TBD Sa, Okt 3, 09143PACS TBD So, Okt 4, 09144PACS TBD Mo, Okt 5, 09145PACS TBD Di, Okt 6, Mi, Okt 7, Do, Okt 8, 09148SPIRE/PACS parallel Fr, Okt 9, 09149SPIRE/PACS parallel Sa, Okt 10, So, Okt 11, Mo, Okt 12, 09152PACS TBD Di, Okt 13, 09153PACS TBD Mi, Okt 14, End of PV IAS map making workshopIAS, 10 July 2009

6 PACS Status Report WE Operation Except for DPU memory hiccup during first switch-on, no major flaws encountered Very complex S/W system (ground segment, spacecraft, instrument) has led to failed (or non-optimum) execution of intended tests, already On-board data compression seems to work, to first order; optimization necessary/possible after adjustment of detector biases etc. on actual telescope background No need to try out redundant branch! IAS map making workshopIAS, 10 July 2009

7 PACS Status Report Chopper Needed for rapid modulation on/off source on sky Also used to look at calibration sources Performance as on ground - final optimisation coming IAS map making workshopIAS, 10 July 2009

8 PACS Status Report Calibration Sources Dynamics and temperature stability is nominal Temperatures may have to be adjusted to match (lower) telescope background IAS map making workshopIAS, 10 July 2009

9 PACS Status Report Filter Wheels Needed to select “blue” (70µm) or “green” (100µm) photometer band Needed to select 2 nd vs. 3 rd grating order in “blue” spectrometer Nominal performance in orbit verified IAS map making workshopIAS, 10 July 2009

10 PACS Status Report Grating Drive Has to actuate grating angle - over 40 deg range - to arcsec absolute accuracy, with milliarcsec/√Hz noise Achieved in-orbit performance better than on ground 10 IAS map making workshopIAS, 10 July 2009

11 PACS Status Report 300mK 3 He Sorption Cooler for Bolometers Performance under zero-g not tested on ground Operation/performance in orbit better than on ground - lowest T ever reached outside of CEA lab K Pump temperature is now stable when the "steady-state" heater current is applied. Leaks through the thermal shunt are drastically reduced IAS map making workshopIAS, 10 July 2009

12 PACS Status Report 300mK 3 He Sorption Cooler Operation Cold side runs 1K colder than before. Better insulation in the thermal shunt. Evaporator driven below 2K by the cooling strap. More efficient cooling through the strap (temperature peak occurs before the end of pump strong heating) Estimated operating time ~60h t_hold = * t_oper IAS map making workshopIAS, 10 July 2009

13 PACS Status Report Bolometer Operation Bolometer array noise maps: black = no noise (blind), white = high noise (hot) Qualitatively no difference to before launch Glich rate 1/150 s -1 per pixel, glitch duration ~2 frames of 0.1s IAS map making workshopIAS, 10 July 2009

14 PACS Status Report Photometer “Sneak Preview” Requested by ESA directorate - “no” was not an option PS and PACS had serious doubts about feasibility, with no knowledge of background, untested bolometer settings,... Attempt was made, anyway, on 14 June, after lid opening First data arrived on the evening of 15 June  Map making movie IAS map making workshopIAS, 10 July 2009

15 PACS Status Report Photometer “Sneak Preview” Herschel/PACS Images of M51 (“Whirlpool Galaxy”) 70 µm 100 µm160 µm © ESA & The PACS Consortium MADmap PEP MeetingIAS map making workshopIAS, 10 July 2009

16 Spitzer/MIPS 160µm Herschel/PACS 160µm Herschel/PACS 70/100/160 µm

17 PACS Status Report First Point Source (Star) Chop/Nod Observation Blue PSFs have a narrow core (width ~as expected for ideal telescope) Stronger wing than for ideal telescope, triangular shape Overall (core+wing) gaussian FHWM in frame is observed to be ~5-6” vs. 4.5” in a model based on PICC-ME-TN029 PSFs Strehl estimated ~0.6 Same triangular pattern seen on 4 different stars, in point source reduction vs. single frames from scan… NOT a source property. Left: Observation Right: Model IAS map making workshopIAS, 10 July 2009

18 PACS Status Report First Point Source (Star) Chop/Nod Observation Central peak width is nominal “Triangular” wings qualitatively understood in terms of dominating WFE symmetry / calculated spot diagrams IAS map making workshopIAS, 10 July 2009

19 25 August 2006 Herschel Telescope T 3 Plots of the intensity distribution in the paraxial focal plane Thermo-elastic stress on M1 induces an increase in trefoil that is dependent upon the difference in CTE of invar and SiC. CTE Invar 1.64 and SiC 1.00 (at 70 K) CTE Invar 1.97 and SiC 1.00 (at 70K)

20 PACS Status Report As-Built Telescope WFE / Spot Diagram (Cold Test) From 2 different thermal cycles IAS map making workshopIAS, 10 July 2009

21 PACS Status Report Predicted PSF from WFE Effect explained (qualitatively) - telescope, not PACS Thermo-elastic stress on M1 Strehl ratio / main beam efficiency under evaluation IAS map making workshopIAS, 10 July 2009

22 PACS Status Report Pointing Information (4 Stars) Using 0032_0003.SIAM 4 point sources, several scan maps Point sources and CAP 3.1.1: –dy=4.59 stdev 1.35arcsec –dz=5.50 stdev 1.19arcsec –Note that these errors are based on two independent pointings (nod) each Consistent up to OD53 where new offset of ~14 arcsec, observed both in target footprint position and scan map astrometry –ACMS update ? –Thermo-elastic effect on STR, SAA dependent. IAS map making workshopIAS, 10 July 2009

23 PACS Status Report Deglitching Multi-median resolution transform (MMT), Starck et al IAS map making workshopIAS, 10 July 2009

24 PACS Status Report Flux-calibration Will start : –once the final detector biases are implemented (adjusted to the final telescope temperature) –and the high gain is used. IAS map making workshopIAS, 10 July 2009

28 PACS Status Report 1/f noise removal: simple high pass filter IAS map making workshopIAS, 10 July 2009

29 PACS Status Report Telescope Background Spectral scan on cryostat cover and telescope, single pixel. No chopping, no response drift correction; simple glitch removal Telescope background on the lower side of nominal Background measurement with bolometers not quite consistent 86 K 72 K, in orbit nominal telescope 108K, 95K, 85 K telescope background, OD 33 telescope background, OD 38 IAS map making workshopIAS, 10 July 2009

30 PACS Status Report Instrument Anomalies Drop-outs in temperature sensor data “NaN” symptom - no explanation, yet; running tests Could potentially affect T-control of calibration sources? No! IAS map making workshopIAS, 10 July 2009

31 PACS Status Report Instrument/Spacecraft Issues DECMEC performance (chopper control) degraded below 0° C - requested change in temperature limits / heater operation Timing offsets between science data and position information - under investigation; PACS contribution understood, ACMS part apparently, too Interference on bolometer signals? Seen sporadically with amplifier low-gain operation, not with high-gain - but little statistics, yet –without the harness re-routing,... Single-scan PhotProj map reconstruction IAS map making workshopIAS, 10 July 2009

32 PACS Status Report Ground Segment Issues Data seem to arrive at ESOC all complete, but propagation to ICC sometimes incomplete –Delays analysis, which is often time-critical for feed-back into following OD programmes IAS map making workshopIAS, 10 July 2009

33 Let’s keep fingers crossed... PACS Status Report Instrument Status We are about 90% through commissioning All elements of PACS have been successfully operated Optimisation of mechanism control completed First assessment of detector behaviour achieved Line of sight / SIAM established First assessment of PSF achieved Few instrument/satellite anomalies observed so far No major problems encountered, yet IAS map making workshopIAS, 10 July 2009

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