Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 1407c Report Date: 09-May-96:16:38 Version: ********** Check-in Date: ********** 1.Proposal Title: INITIAL DARK NOISE MEASUREMENTS HRS-I5 ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID SV/HRS Sub Category ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Dennis C. Ebbets BALL AEROSPACE SYS. GROUP USA 303-939-5964 ------------------------------------------------------------------------------------ 7. Abstract OV-SV Dark count observations to allow: 1. Spatial resolution of photocathodes 2. 1 second time resolution 3. Measure dark count as function of: a. orbital circumstances - clean orbit, SAA etc. b. temperatures c. other activity within HST 4. Calibrate anti-coincidence capabilities of data quality checks for radiation effects. Correlate GHRS dark counts with HSP radiation monitor counts ------------------------------------------------------------------------------------ 8. Scientific Key Words: HRS, CALIBRATION, SCIENCE VERIFICATION ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 9.70 par: 0 10. Num targs pri: 0 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: HSP HRS ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 1407c PI: Dennis C. Ebbets Proposal Title: INITIAL DARK NOISE MEASUREMENTS HRS-I5 ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ D. C. Ebbets BASG USA Ed Beaver UCSD USA B. D. Savage UNIV. OF WISCONSIN USA K. G. Carpenter NASA/GSFC USA J. C. Brandt LASP/UNIVERSITY OF COLORADO USA ------------------------------------------------------------------------------------ 3. Description of proposed observations. The basic observation is a scan of the photocathode scanning the entire 22mm width. There are 33 observations with 7 substep bins each. The Y deflection increment is 16 steps (400MUm = 1 diode height) between bins. The integration is 1 second at each step. The carrousel should be in its SAFE position, and all lamps should be off. The shutter should be closed. This observation should be run repeatedly for long periods of time (several orbits) to monitor dark count as a function of time, during various orbital environments. Separate tests should be run for each detector. All data quality checks which can censor data will be disabled. This will allow worst-case measurements of all dark count producing events. The observations will be based on the "default OST" ZSHRTSCNY. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. OV-SV Prerequisites 1. detector focus established - HV Turn-on sequence = proposal #1457 2. thresholds determined and loaded - PHA = proposal # 1459 If parallel operations are possible, it would be useful to correlate the GHRS dark counts with the HSP monitor OLT. SV Minimum Plan: lines 9, 10, 12, 13, 1.5 SV Delta Plan: lines 11, 14 Guiding Tolerance: none - internal test only These are internal tests and do not require any special pointing of the telescope. They do not demand that HRS be prime instrument, unless the frequent data readouts preclude operating in parallel. We request six observing runs of one full orbit duration each. It is not necessary that they be contiguous. The GROUP WITHIN 1 WEEK requirement will ensure similar detector focus & thresholds. We do request that the observations on lines 9 and 12 be clean orbits, well outside the SAA. Lines 10 and 13 should be orbits with maximum SAA penetration. Lines 11 and 14 may be scheduled for any convenient time. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. These observations will result in a readout of 7 bins from the HRS several times per minute. The operations staff should consider whether HRS can be operated as a parallel SI and still readout so frequently. It is necessary that long time sequences of dark count data be obtained in order to investigate the effects of orbital environments and spacecraft activity on the background count rates. It is highly desirable that the HRS not be "idled" during these observations. We wish to have long baselines of continuous data. Page 3 ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. 1. Compare mean count rates for 500 science diodes, 4 corner diodes, 5 focus diodes and 2 radiation diodes. 2. Look for spatial effects (hot spots) on the photocathodes. 3. Correlate count rates with orbital circumstances. 4. Look for noise correlated with other activities in HST. 5. Compare statistics for all size diodes - are mean count rates the same or are there unusually noisy or quiet channels. 6. Correlate radiation diode counts to mean counts on science diodes - now many counts come from photocathode hits vs. diode array and pre-amp hits. There are no updates to project data bases required. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). Data analysis facilities Personnel Travel and publications support ------------------------------------------------------------------------------------ 12. There is no Target List with this proposal. Dark count observations should be run as frequently as possible for as long a duration as possible. ------------------------------------------------------------------------------------ 11. Address Information Name: ED BEAVER Category: CON Institution: UCSD Address: CASS City: LA JOLLA State: CA Zip Code: Country: USA Telephone: Telex (or e-mail): ------------------------------------------------------------------------------------ Name: KENNETH CARPENTER Category: CON Institution: NASA/GSFC Address: CODE 680 City: GREENBELT State: MD Zip Code: 20771 Country: USA Telephone: 301-286-3453 Telex (or e-mail): ------------------------------------------------------------------------------------ Name: BLAIR SAVAGE Category: CON Institution: DEPT. OF ASTRONOMY Address: UNIV. OF WISCONSIN City: MADISON State: WI Zip Code: 53706 Country: USA Telephone: 608-262-0309 Telex (or e-mail): ------------------------------------------------------------------------------------ Name: DENNIS C. EBBETS Category: PI Institution: BALL AEROSPACE SYS. GROUP Address: P.O. BOX 1062 FT-3 City: BOULDER State: CO Zip Code: 80306 Country: USA Telephone: 303-939-5964 Telex (or e-mail): ------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 1407c [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 DEFINE DARK HRS PHOTOSC NONE # TYPE=LONG-Y 12 231 S 1 DMAP AN SPACING=16 X=2048 Y=2048 Comments: LONG-Y CONTAINS 33 OBS. OF 7 BINS EACH, SPACING BETWEEN BINS = (DELTA)Y DEFLECTION STEPS. 1 SEC EXP FOR EACH BIN=231 SEC. REPEAT EXPOSURES 12 TIMES IN A ROW. DOPPLER IS ASSUMED TO BE OFF. ------------------------------------------------------------------------------------------------------------------------------------ 9 USE SAFE1 GROUP 9-10 WITHIN DMAP 7D CYCLE 0 / 9-14 Comments: DETECTOR D1. CLEAN ORBITS WITH NO SAA EXPOSURE. ------------------------------------------------------------------------------------------------------------------------------------ 10 USE SAFE1 DMAP Comments: DETECTOR D1. NOISY ORBITS WITH MAXIMUM SAA PENETRATION. ------------------------------------------------------------------------------------------------------------------------------------ 11 ^ ^ ^ COND IF SV DELTA PLAN Comments: DETECTOR D1. ANY AVAILABLE ORBITS. ------------------------------------------------------------------------------------------------------------------------------------ 12 USE SAFE2 GROUP 12-13 WITHIN DMAP 7D Comments: DETECTOR D2. CLEAN ORBITS WITH NO SAA EXPOSURE. ------------------------------------------------------------------------------------------------------------------------------------ 13 ^ ^ ^ Comments: DETECTOR D2. NOISY ORBITS WITH MAXIMUM SAA PENETRATION. ------------------------------------------------------------------------------------------------------------------------------------ 14 ^ ^ ^ COND IF SV DELTA PLAN Comments: DETECTOR D2. ANY AVAILABLE DATA. ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 1407c [ 5] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HRS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes PHOTOSCAN ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters TYPE=LONG-Y SPACING=16 X=2048 Y=2048 ------------------------------------------------------------------------------------------------------------------------------------ Proposal for SV/HRS ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 9.70 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GROUP 9-10 WITHIN 7D; CYCLE 0 / 9-14; COND IF SV DELTA PLAN GROUP 12-13 WITHIN 7D; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements # SAFE1 ^ SAFE2 ------------------------------------------------------------------------------------------------------------------------------------ Target Names ------------------------------------------------------------------------------------------------------------------------------------