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SOT Initial Operation in Commissioning Phase Y. Katsukawa (NAOJ) SOT team SOT17 @ NAOJ 1 Apr 17-22, 2006 SOT initial operation overview Y+ I Spacecraft verification and checkout phase 7-20 Before installation to the nominal orbit FPP on, initial status check CCD decontamination II SOT instrument checkout phase (1) Instrument verification 21-29 (TBD) Before OTA top door opening Basic function check Obtain dark images III SOT instrument checkout phase (2) First light phase 30-45 (TBD) After OTA top door opening Optical performance checkout Correlation tracker In-flight calibration IV Performance verification phase 46- 60 (TBD) V Initial Science Phase for SOT core team 60d – 6months Apr 17-22, 2006 SOT17 @ NAOJ Run all the kinds of observables with combination In-flight calibration (continued) Used for dedicated scientific purpose In-flight calibration (continued) 2 (I) Spacecraft verification and checkout phase Period: Launch Y+20 Orbit control maneuvers are carried out several times to install the S/C to the sun-synchronous orbit. No Event Perigee (km) Apogee (km) Inclination () Date 0 Launch 243.6 590.1 97.79 1 Test maneuver 253.3 590.1 97.79 Y+3 2 Perigee-up maneuver #1 441.7 590.1 97.79 Y+6 3 Perigee-up maneuver #2 630.0 590.1 97.79 Y+11 4 Perigee-up maneuver #3 630.0 630.0 97.79 Y+14 5 Out-of-plane maneuver #1 630.0 630.0 97.80 Y+17 6 Final orbit control Y+20 Check-out of S/C attitude control system is also performed during this period. Apr 17-22, 2006 SOT17 @ NAOJ 3 (I) Spacecraft verification and checkout phase Apr 17-22, 2006 SOT17 @ NAOJ 4 (I) Spacecraft verification and checkout phase After a#1 (Y+6), the altitude of S/C becomes high enough, and the attitude of S/C is controlled by MWs. During the period between Y+7 and Y+20, we plan to do initial status check (temperatures) and CCD heater operation. Primary objective is to decontaminate the CCDs. a#2 MDP and FPP ON CCD decontamination heater ON 3days 1.5 days CCD decontamination heater OFF FPP and MDP OFF a#3 Apr 17-22, 2006 SOT17 @ NAOJ 5 (II) SOT instrument checkout phase (1) Period: Y+21 Y+28 (TBD) (1 week) From the installation to the sun-synchronous polar orbit To opening the SOT top door The primary objectives are (1) decontamination of M1, M2, and HDM, and (2) initial functional checkout without sunlight into the telescope. The test items of this phases are the following – – – – – – Verify function of operational heaters for OTA and FPP Open the telescope side door Decontamination of M1, M2, and HDM Verify function of mechanisms (shutters, filter wheels etc.) FG, SP, and CT image acquisition Automatic observation by MDP table control Obtaining dark images is also important items especially for SP because there is no shutter in the SP optical path. Apr 17-22, 2006 SOT17 @ NAOJ 6 (II) SOT instrument checkout phase (1) Y+ OTA / CTM 20 CTM ON, check OTA heaters 21 OTA side-door opening Decontamination heaters ON FPP FPP ON / operational heaters ON 22 CCD heaters ON / Cameras ON 23 PMU ON / Mechanisms check 24 Tip-tilt mirror ON / PZT voltage test Checkout FG table observations 25 Checkout SP table observations 26 Dark images 27 Dark images / Camera noise 28 Dark images 29 Preparation for door operation 30 OTA top-door opening Decontami heaters OFF Operational heaters ON Apr 17-22, 2006 Verify obs. table for door operation SOT17 @ NAOJ 7 (II) SOT instrument checkout phase (1) Obtaining dark images – Obtain the images with some camera setting (gain, amplifier) – Orbital variation, temperature dependence – Effect of cosmic radiation on the images All the data taken during this period is to be down-linked at the Uchinoura station (USC). Some of them will be down-linked at the Svalvard station (SVA) in order to test data transfer system from SVA to Japan. Apr 17-22, 2006 SOT17 @ NAOJ 8 (III) SOT instrument checkout phase (2) Period: Y+30 Y+45 (TBD) (2 weeks) First light phase after the telescope door is opened The primary purpose of this period is verification of optical performance – – – – Alignment with respect to sun-sensor, XRT, and EIS Image quality and focus stability Correlation tracker performance Function of FG and SP observables, etc. In-flight calibration of the instruments – Darks and flat fields – Polarization – TF wavelength tuning etc. Apr 17-22, 2006 SOT17 @ NAOJ 9 (III) SOT instrument checkout phase (2) Y+ S/C major event FG SP CT 30 OTA top-door opening Initial optical check Coarse focus scan Initial optical check Coarse focus scan Initial optical check Coarse focus scan 31 XRT door opening (background obs) (background obs) (CT jitter data) 32 EIS clamshell opening (background obs) (background obs) (CT jitter data) 33 Update pointing offsets (background obs) (background obs) CT servo-on /off (background obs) (background obs) CT servo-on (ready for running) Fine focus scan (adjust focus) Fine focus scan (adjust focus) Fine focus scan 36 (Flat fields) Continuous obs (Flat fields) Continuous obs 37 TF wavelength scan (adjust tuning) (background obs) 38 TF wavelength scan (background obs) 39 NFI observables (background obs) 34 35 Tracking start (around DC) Apr 17-22, 2006 SOT17 @ NAOJ CT wedge check 10 (III) SOT instrument checkout phase (2) Y+ S/C major event FG SP CT 40 Pointing to limb Image quality stability Image quality stability CT wedge check 41 Limb optic check Limb optic check 42 TF wavelength scan (background obs) 43 NFI observables (background obs) Image quality stability Image quality stability NFI observables (background obs) 44 Go back to DC 45 Apr 17-22, 2006 SOT17 @ NAOJ 11 (1) Top-door opening / Initial optical check One of the most critical event in the initial operation Make the satellite pointing to the disk center Light level is continuously monitored by CT live images when the door opening operation. After the top-door is successfully opened, we plan to switch observation tables to carry out the initial optical checkout. – Light level check for FG (all the wavelengths), SP, and CT – SP 6301.5/6302.5 spectrum line positions and profiles – Alignment check to the sun-sensor (chromospheric features may provide pointing information even in QS) Quick focus scan and adjustment are planned to be done in realtime operation half a day after the door operation. Apr 17-22, 2006 SOT17 @ NAOJ 12 (2) Background observations during the operation of the other telescopes SOT commanding operation cannot be done during the door opening operation of the other telescopes. We plan to run some observation tables in background with low cadence in order to verify the following items. – – – – – – – Data transfer from Svalvard station Image compression efficiency Dark images, flat fielding (by averaging many images) Camera noise (light transfer measurement) Alignment with respect to XRT and EIS CT diagnostic data to get S/C jitter information SP full FOV scanning (to check vignetting and alignment) BFI observations (e.g. G-band) with shorter exposure can be possibly carried out without correlation tracker. Such observations with longer duration may provide information on orbital variation of image quality. Apr 17-22, 2006 SOT17 @ NAOJ 13 (3) Correlation tracker servo-on / Detailed verification of optical performance After CT servo is turned on, we can go to detailed verification and calibration of optical performance. Fine focus scan – Image quality evaluation – Co-focus among different channels – Adjust focus position if necessary Continuous observations for several hours with a few wavelengths – Orbital variation of image quality – Inter-channel alignment – Image quality degradation by disturbance from FPP, XRT and EIS Flat fielding – Flat fielding by intentionally move the tip-tilt mirror Tunable filter (TF) wavelength scan/ NFI observables – TF spectroscopic performance – Update tuning parameters if necessary – Verification of MDP Doppler velocity compensation Apr 17-22, 2006 SOT17 @ NAOJ 14 (4) Limb observation After optical performance verification is done near the disk center, we like to go to limb observation. The verification items in the limb observation are – – – – – S/C pointing check Image quality and focus change between DC obs and limb obs Scattered light TF wavelength tuning, MDP Doppler compensation Function of the correlation tracker in limb obs. Apr 17-22, 2006 SOT17 @ NAOJ 15 Pointing and target selection in the first light phase We have to know misalignment with respect to the sun sensor (ACS), XRT, and EIS as fast as possible for the secure operation. After the satellite pointing is established, we like to track a suitable active region near the disk center if we have for verification of the optical performance (as well as scientific interest). When the verification near the disk center is done, the limb observation is necessary to verify performance of SOT at the limb. We may go to the limb observation automatically by tracking an active region in the first light phase. After the limb observation, we can make SOT pointing to any region. Apr 17-22, 2006 SOT17 @ NAOJ 16 (IV) Performance verification (PV) phase Period: Y+46 Y+60 (TBD) (2 weeks) After the first light phase The primary purpose in this phase is verification of scientific performance of the SOT observables Background: – SOT has a capability to observe various scientific targets. – Wavelength coverage BFI 6 channels, NFI 6 channels, and SP 6302A – Many types of observables Single image, LOS magnetograms, Stokes IQUV, and Dopplergrams – Temporal and spatial sampling Knowledge obtained in this phase shall be used for following scientific operation. Apr 17-22, 2006 SOT17 @ NAOJ 17 (IV) Performance verification (PV) phase Phase-I – At first, we verify performance of high-priority observables with a typical wavelength to verify basic scientific performance of SOT – Only one observable or simple combination are used for long duration (several hours half a day). – SP observations can be carried out simultaneous with FG. Phase-II – After the verification of each observable is completed, we make combined observations with multiple wavelengths and observables. – SP observations can be carried out simultaneous with FG. Apr 17-22, 2006 SOT17 @ NAOJ 18