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Status of development and testing of the XRT Data Analysis Software. F. Tamburelli, M. Capalbi, B. Saija, M. Perri, S. Granata, ASDC Paolo Giommi, ASI/ASDC L. Angelini, HEASARC. Current Delivery Status. S even delivery builds are planned : Build 6 delivered on August 5th
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Status of development and testing of the XRT Data Analysis Software F. Tamburelli, M. Capalbi, B. Saija, M. Perri, S. Granata, ASDC Paolo Giommi, ASI/ASDC L. Angelini, HEASARC
Current Delivery Status Seven delivery builds are planned : • Build 6 delivered on August 5th • Next Build (7) due on October30th • New build delivery after the launch However discussion under way to revise the above schedule. Probably build 7 will be delayed two weeks and another build added before the launch (february 2004)
Tasks Delivered for Build 6 (August 5th) Modification & upgrade of existing tasks • xrtph2br – Computes single PHA value and assigns event grade for the PC mode. Added support for the XMM grades. User can request also to grade data accordingly with ASCA grades • xrtevtrec - Performs Event Recognition for Timing Modes. Added PD modes support and checks for guard pixels for WT mode • xrtimage –Processes IM mode data. Now subtracts the bias and cleans the image for bad pixels (using the CALDB pixel list) • xrtmkarf – Creates an Ancillary Response File (ARF). Added support for timing modes, but delivered only for PC mode New tasks xrtproducts - Generates Standard Products for the PC mode region extraction of lightcurve, spectrum at the burst/afterglow location, Image FOV
Tasks Planned for Build 7 (October30th) Modification and upgrade of existing tasks • xrtevtrec– To be modified if the 6 pixels Leicester patterns substitute what already implemented • xrttimetag - Assigns time to each event for PD & WT modes based on a source position. Upgrade to use the S/C attitude to recalculate a time dependent source position • xrtproducts –Upgrade togenerate standard products for timing modes • xrtimage – Upgrade to create an image in counts by summing all DN images. • xrtmkarf –Test and delivery for the timing modes support New tasks TAM correction- Creates routines that calculate the shift in detector and sky to apply to the S/C attitude Imaging processing script- To run in sequence coordinates transformation, bias corrections and bad pixel tasks and create a DN good sky image
Tasks Planned for Build 8 (Feb 2004 ?) and after launch Build 8 • xrthotpix - Performs hot pixel identification • xrtmkexpo - Generates the Exposure Map • xrtcentroid - Performs Source Centroid Computation • xrtbarycorr-Performs Times Barycentric corrections (TBC) • TAM correction (continue from Build 7 if not fully completed and/or tested) • UTCF correction (people at GODDARD are discussing it, the option suggested is to accumulate UTCF into a file and then a new ftool will update times as necessary) After launch • xrtpileup -(XRT Task) Performs pile up identification
Photon Counting Event Recognition • The Photon Counting telemetered a 3x3 matrix • The XMM patterns are defined using 5x5 matrix • Implemented by removing the external ring from the XMM patterns • Some ASCA Grades do not match XMM patterns. They are: • ASCA GRADE 5 ( L shapes including a corner pixel) for example: • ASCA GRADES 2/3/4/6 when a corner pixel is over threshold; • ASCA GRADE 7 ( all patterns not covered by 0,1,2,3,4,5,6 grades ) for example: Local maximum Over split threshold Below split threshold • Added Grade number 32 to store these pattern telemetred
Photon CountingGrades Statistic • Distribution of XMM and ASCA grades among PC events:
Photon CountingGrades Statistic Contribution of ASCA Grades to grade 32: Target G32 G2 G3 G4 G5 G6 G7 73438_03 1550 33 9 13 534 8 953 73334_02 427 16 6 7 209 1 188 73333_01 429 8 6 4 164 2 245
PC Grade distribution : 73438-03 Fe K - rate@CCD 1.2 TOTEVT TOT XMM XMM ASCA No cal 0-12 13-32 02346 117049 47408 47236 172 47241 ASCA 02346 and XMM 0-12 distributions are identical !
Grade 0 (single pixel events) Grade 1-4 (2 pixel events) Grade 5-12 (3 and 4 pixel events) Photon Counting: spectra extracted in PI 73125-03 Al (1.487 keV) Count Rate = 1.19 cts/s 73334-02 Ti (4.511 keV) Count Rate = 2.92 cts/s
Windowed Timing Event Recognition GRADE 0 Single pixel event GRADE 1 Two pixels event right shifted GRADE 2 Two pixels event left shifted Windowed Timing Event Reconstruction algorithm uses 3x1 pixels around a local maximum. Algorithm implemented: • Input Parameters: EVENT THRESHOLD SPLIT THRESHOLD OUTER THRESHOLD (optional) • 3x1 reconstruction: The reconstructed PHA is the sum of the event grade and the two or three pixels related to the event if over the split threshold. • Optional check on guard pixels added. Open Items: • Is this pattern OK ? • What default Outer Threshold value should be used ? • How reconstruct the event PHA GRADE 3 Three pixels event Local maximum Over split threshold Below split threshold CHECK ON GUARD PIXELS: Guard Pixels
Photon Counting and Windowed Timing PC 73438-03 Fe (6.404 keV) Rate@CCD 1.2 and WT 73438-01 Fe (6.404 keV) Rate@CCD 1.2 Spike at low energy: Bad pixel 318 284
Grade 0 (single pixel events) Grade 1-2 (two pixel events) Grade 3 (three pixel events) Windowed Timing: spectra extracted in PI 73130-01 Al (1.487 keV) Count Rate = 61 cts/s 73700-05 Ti (4.511 keV) Count Rate = 294 cts/s
Photodiode Event Recognition GRADE 0 GRADE 1 GRADE 2 Photodiode Reconstruction algorithm uses5x1 pixels around a local maximum. Algorithm implemented: • Input Parameters: EVENT THRESHOLD SPLIT THRESHOLD • 5x1 reconstruction: The reconstructed PHA is the sum of the local maximum DN and the DN of pixels related to the event if over the split threshold. Open Items : • Is this pattern ok ? • To be implemented the 7x1 to account for the guard pixels. What default outer threshold should be used ? • How to reconstruct the pha GRADE 3 GRADE 4 GRADE 5 GRADE 6 GRADE 7 GRADE 8 GRADE 9 GRADE 10 GRADE 11 All other patterns Local maximum Over split threshold Below split threshold
Photodiode and Windowed Timing Event Recognition For consistency with the 3x3 PC Mode, patterns for PD & WT are set to 5x1 & 3x1 PC WT PD Local maximum But to “better” define (ONLY) the local maximum a 5x1 and 7x1 pixel array could be considered to include the guard pixels for the WT and PD respectively Note the PC mode has disabled on board the check for the guard pixels • Leicester and e-mail discussion on pattern definition : • Reconstruction of the PHA values for the WT (and PD ?) should account for the larger array 5x1 & 7x1 (Abbey). Effectively this is redefining the patterns and change consistency with the PC mode • 6x1 pattern (Osborne) no clear rules to how : • how to select an event from the event list to start the pattern reconstruction • define the pha (how many pixels to use) • If guard pixels are included and if so how the threshold is defined. Is it different from the split threshold? • Open items : What will do with the latter two ?
Other Open issues : PD PhotoDiode (1) The pixels for the first frame are not quite the same as the rest of the pixels. • The first pixel contains garbage, next five are guard pixels with no sky signal events. Exposure time for these 6 pixels of the first frame is zero • Next 602 are from the framestore and have 0 exposure to sky but increasing exposure to background events • The exposure monotonically increases for both background and sky in the next 602-1807 pixels • It is planned to remove all the first 1807 pixels from the first frame (build 7) • Problem: how to work out what is the first frame assuming that there maybe will be damaged or gap in the telemetry. Should we use a standard time interval of TBD seconds to establish that the PD mode restarted? PhotoDiode (2) • Currently the software subtracts the bias from ground calibration stored in CALDB • The last 20 pixels in both PD modes for each frame can be used to evaluate the bias • Should the bias be calculated from these pixels ? • Currently the reformatting software calculates the average and standard deviation for LR mode • Should this value be used instead and/or the histogram approch suggested by Dave?
TAM corrections Two different corrections to be applied: • TAM primary image offset to correct detector coordinates (eq 4.1 & 4.2 XRT-PSU-037) • TAM star tracker image (secondary) offset to correct the attitude data The latter is sensitive to changes in both XRT boresight and the Star Tracker boresight. Therefore to correct the attitude the primary offset must be subtracted to the secondary offset However both corrections could be applied to the attitude. • To achive that, also the DETX/Y shifts are translated into corrections to the attitude • The TAM corrections will be applied with the following steps: • Task to calculate the shifts in DETX/Y and dalpha and ddelta from the packet header values • Task to calculate corrections to be applied to the attitude • Tasks that applies the corrections to the original attitude file The following input/clarifications are needed: • Integration time <1 second for TAM images however telemetry contains images every 5 minutes. Are these images an average of the ‘sub-second’ images or not? • The science packet contains the TAM offest values in the header. How these values were obtained considering that the integration time for each frame is different from the TAM images integration ? • Are TAM images sent to the ground regardless of the satellite status (pointing or slewing) ? • Plan to test if the TAM is applied correctly needed
CALDB delivered files : Current Content Delivery from LU (total files 22 ) • 11 arf for different modes and grades • 8 matrices: 3 for PC; 3 for PD; 2 for the WT • 1 Quantum Efficency • 1 Filter transmission • 1 TAM reference positions and related data Delivery from PSU (total files 10) • 2 Bad pixel information • 3 Gain coefficient • 2 Bias PD and IM • 1 Waveform setting • 1 Temperature CCD (unit should be Kelvin) • 1 HK conversion factors Delivery from OAB (total files 8) • 3 arf one for each mode • 1 PSF coefficient description • 1 PSF encircled energy function • 1 Vignetting coefficent • 1 Filter transmission • 1 Effective area Createad at ISAC/Rome (total file 3) • 1 Grade description file • 1 HK range to define data selection • 1 Telescope definition file
CALDB Current Open issues Format Problems • Missing keywords: many of the files were delivered with basic keywords described in the CALDB document missing. These were included at ISAC, future delivery should take into account those changes. • In the Response Matrices the first channel is set to a low negative value. Problem for XSPEC . Could this value be set to zero? Duplicated files • Arf delivered from OAB and LU. OAB responsible. The delivery from LU will be not included in the XRT CALDB. • Filter Transmission from OAB and LU. LU responsible. The delivery from OAB will not be included in the XRT CALDB. Files not yet delivered • Background events files (and spectra?) for each mode Changes in the file structure • Gain : it has been pointed out that a different file structure is needed for a better description of the gain spatial dependence. • PSF coefficent file : we suggest a different structure.