RHESSI LEVEL 0 DATA AND QUICKLOOK DATA PRODUCTS J MCTIERNAN UCB/SSL

1. RHESSI LEVEL 0 DATA AND QUICKLOOK DATA PRODUCTS J MCTIERNAN UCB/SSL

2. LINKS: (All in need of updates) • This Document: http://sprg.ssl.berkeley.edu/~jimm/hsi_20020418.ppt • Level 0 Data Handling: http://sprg.ssl.berkeley.edu/~jimm/hessi/hessi_data_handling.html • Quicklook Data Products: http://sprg.ssl.berkeley.edu/~jimm/hessi/hsi_obs_summ_soc.html • Flare List: http://sprg.ssl.berkeley.edu/~jimm/hessi/hsi_flare_list.html • File database: http://sprg.ssl.berkeley.edu/~jimm/hessi/hsi_filedb.html • Quicklook info and data structures: http://sprg.ssl.berkeley.edu/~jimm/hessi/qlook_structures.html

4. Data Products • LEVEL 0 DATA FILES: usually 1 per orbit, telemetry packets with appended catalog; FITS binary extensions. “hsi_yyyymmdd_hhmmss_nnn.fits “. Max. Size=100Mbytes. “Orbits” start and end in SC night. • Plot files (PNG format), images, spectra, and count rate plots. • Daily Catalog files, online: “hessi_catalog_yyyymmdd.fits”, hsi_instrument_log_yyyymmdd.fits, available with SSW. • Flare List,: “hessi_flare_list.fits”, also an ascii file: “hessi_flare_list.txt” • Database file, contains file names, time ranges: “hsi_filedb.fits”

5. Data Issues and Gaps: • 1.8 Gbytes per day of data (128 Gbytes total as of 15-Apr-2002) • Approximately 2/3 of files need reprocessing due to : • Ground Station - SOC (Science Ops Center) connection (rare) • SOC Unix scripts (rare) • IDL bugs and ‘features’ (common, but easier to fix) • Files for HEDC flares have been reprocessed and qlook data has been appended, should work as planned.

6. HSI_FILEDB • Each file is recorded as an entry in the filedb structure. This is written into a FITS file, which is opened and read and rewritten for every ground station contact. The database file for all level 0 data is distributed as part of the software. • Contents: • version = A version number • file_id = file name • orbit_start, orbit_end = Orbit number (GDS) at start and end of the file • start_time, end_time = data start and end times • status_flag = set to -1 if the file has been discarded, and the packets are contained in another file, set to 0 if the file is active • npackets = Number of packets • clock_drift_start, clock_drift_end = the value of the clock drift at file start and end

7. For Each Level 0 File: Observing Summary • Hsi_obs_summ_rate: Spin-averaged count rates in 9 energy bands, summed over detectors, 4 second (~one spin period) time resolution. (Excludes detectors 2, 7, 8) • hsi_mod_variance: Modulation variance, Front Segments 8 and 9. • Hsi_ephemeris: S/C position and velocity, 20 sec (~5 spin periods) resolution. • Hsi_qlook_roll_period, hsi_qlook_pointing: 10 arcsec resolution S/C pointing estimate and Roll period estimate, 20sec time resolution. (Not yet Implemented) • hsi_obs_summ_flag: Data Flags, including: ['SAA_FLAG', 'ECLIPSE_FLAG', 'FLARE ‘, ’NON_SOLAR_EVENT', 'FRONT_RATIO', 'DECIMATION WEIGHT', ‘DECIMATION ENERGY’, 'SSR_STATE', 'ATTENUATOR_STATE’]

9. InstrumentLog: • Hsi_qlook_monitor_rate: Quicklook Monitor Rates, 20 sec cadence • hsi_qlook_rate_per_det: Count Rates per detector, summed over all energies, 20 sec • hsi_qlook_packet_rate: Packet Rate, all app_ids, 5 minutes • To be included: SOH data, temperatures, On-board memory usage, etc…

10. Finding Flares: • Use 1 min running average in 12 to 25 keV range to determine threshold count rate. Intervals with count rates from 12 to 25 keV greater than the threshold are flagged. Threshold is 3 sigma. (All thresholds are expected to be changed after we see real data). All the files for a given orbit are used in the flare_list routines • Verify Solar events by checking: • 1) Modulation variance must be greater than 3 sigma above background level. (modvar=10*(variance per spin)/(counts per spin)). • 2) Front-Rear count ratio must be greater than 3 sigma above background level (front_ratio=front_counts(<300 keV)/(front_counts(<300 keV)+rear_counts(>300keV))). • For events determined to be solar, the above criteria are used to adjust the flare end time.

11. Flare Position: • Flare position is found using a back-projection image for the peak 4 second interval of the flare. (Not Currently Implemented) • 64 X 64 pixels - 35 arcsec resolution.

12. Flare List • Hsi_flare_list: Id number . • Start, peak and end times, in energy range [12.0, 25.0] keV • Peak count rate, counts/sec/segment and total counts, corrected for attenuator state • Background Count rate and Time Range. • Highest energy of observed photons . • Flare position, arcsec from Sun center. • Flags for flares that start/end in Eclipse or SAA, flares at file SOF, EOF. • Non-solar event flag. • Detector Id's (Fronts only are used for flares, both can be used for others). • File(s) which have the data .

13. Quicklook Spectra and Images • Hsi_qlook_spectrum: “Semi-Calibrated” (I.e., diagonal response matrix) photon spectrum at flare peak, 392 energy channels, dE = 1 to 100 keV, larger at higher energies, with 1 keV channels near 511 and 2200 keV. (Not Implemented) • hsi_qlook_image: Images at flare peak, 5 arcsecond spatial resolution, CLEAN algorithm, in the energy bands given by the Observing Summary, [3, 6, 12, 25, 50,100,300,1000,10000, 20000] keV (Not Implemented)

14. Data Access: Command Line Interface: • Define object: • IDL> o=hsi_obs_summary(class_name=‘hsi_obs_summ_rate’) • OR • IDL> o = obj_new(‘hsi_obs_summ_rate’) • IDL> data=o->getdata(obs_time_interval=‘20-feb-2002 ‘+[‘09:00’, ‘11:00’]) • Use of obs_time_interval reads data from the data in HSI_DATA_ARCHIVE, with filenames found from the file ‘hsi_filedb.fits’ in $SSW/hessi/dbase. • Other control parameters: filename, time_range, all are for use on files independent of the archive • Other Methods (from Kim): plot, list • IDL> o -> plot, /saa, /flare, /eclipse

15. HSI_QLOOK_SUMMARY_PAGE • Summarizes data for each orbit: • o=hsi_qlook_summary_page(obs_time_int = [whatever]) • o->list