Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 5745 Report Date: 18-Jul-95:17:55 Version: ********** Check-in Date: ********** 1.Proposal Title: GHRS PSF IMAGING TEST ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID CALIBRATION CAL/HRS Sub Category ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Stephen Hulbert STSCI USA 410-338-4911 ------------------------------------------------------------------------------------ 7. Abstract The purpose of this program is to determine the nature of the PSF that is presented to the GHRS by the COSTAR mirrors. We will measure the PSF using a DWELL SCAN and integrate so as to reduce the effects of spacecraft jitter. The target used for this test is in the CVZ. ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 2.99 par: 0 10. Num targs pri: 1 par: 0 ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 5745 PI: Stephen Hulbert Proposal Title: GHRS PSF IMAGING TEST ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Stephen Hulbert STSCI USA George Hartig STSCI USA David Soderblom STSCI USA ------------------------------------------------------------------------------------ 3. Description of proposed observations. The purpose of this program is to determine the nature of the PSF that is presented to the GHRS apertures. We will make use of a DWELL SCAN to scan the small science aperture across the PSF. We will sample the the PSF on a scale of 0.053 arc sec (equal to 2 deflections unit in the GHRS detector space). Exposure times will be 30 s at each dwell point to average over a few cycles of the dominant spacecraft jitter (0.1 Hz). The sequence of observations is: 1. 5x5 ONBOARD ACQ w/MIRROR-N1 2. 5x5 ACQ/PEAKUP in SSA w/MIRROR-N1 3 5x5 ACQ/PEAKUP in SSA w/MIRROR-N1 to ensure target is centered in SSA 3. 15x15 DWELL SCAN (spacing = 0.053 arc sec) in SSA w/MIRROR-N1 using RAPID mode The target used in this test is in the CVZ. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. The purpose of this program is to determine the nature of the PSF that is presented to the GHRS apertures by the COSTAR mirrors. The need for this test is driven by the apparent discrepancies among the currently observed SSA/LSA ratio, the ratio determined during the focusing of the COSTAR mirrors, and the predicted ratio. IMAGE data suggests that the PSF may in fact be asymmetric, thus allowing different apertures and spectral elements to "see" different amounts of light. To test this hypothesis we will measure the PSF; the PSF measurement will be done by moving the spacecraft and sampling the PSF with the SSA. Previously, we have seen evidence that there may be a small positional offset between where throughput is greatest for a grating and where it is maximized for a mirror (see GHRS ISR-044). The proposed program contains observations with both the G140L grating and MIRROR -N1 which will allow us to look for similar offsets. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. SPECIAL REQUIREMENTS: Target is in the CVZ. ------------------------------------------------------------------------------------ 11. Address Information Name: STEPHEN HULBERT Category: PI Institution: STSCI Address: City: State: Zip Code: Country: USA Telephone: 410-338-4911 Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 5745 [ 3] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial |Acqui|FLX| Flux data No | Name | Description | Position |Eqnx | Vel. |Prblm|REF| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 1 SK-65D21 WO- B,113; PLATE-ID = 06AF, 2000.0 V = +280 BKG 1 TYPE = B0 IA 39 EXT-STAR; HOST=LMC; RA = 05H 01M 22.326S +/- 1 V = 12.02 EARLY TYPE; 0.50", 1 E(B-V) = 0.10 TYPE = B0 IA; DEC = -65D 41' 48.14" +/- 2 B-V = -0.16, U-B = -1.06 0.50" 3 F-CONT(1275) = 1.88 +/- 0.00 E-12 4 F-CONT(1585) = 9.55 +/- 0.00 E-13 ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 5745 [ 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 SK-65D21 HRS ACQ 2.0 MIRROR-N1 SEARCH-SIZE=5 1 25S 1 ONBOARD ACQ FOR 15 BRIGHT=RETURN -20 CYCLE 4 / 10-40 Comments: STEPTIME=1.0S EXPECT APPROX. 2800 COUNTS/S TARGET IS IN CVZ ------------------------------------------------------------------------------------------------------------------------------------ 15 SK-65D21 HRS IMAGE 2.0 MIRROR-N1 NX=16 1 256S 1 NY=16 DELTA-X=4 DELTA-Y=4 Comments: STEPTIME=1.0S ------------------------------------------------------------------------------------------------------------------------------------ 20 SK-65D21 HRS ACQ/ 0.25 MIRROR-N1 SEARCH-SIZE=5 1 25S 1 ONBOARD ACQ FOR 25 PEAKUP Comments: STEPTIME=1.0S ------------------------------------------------------------------------------------------------------------------------------------ 25 SK-65D21 HRS ACQ/ 0.25 MIRROR-N1 SEARCH-SIZE=5 1 25S 1 ONBOARD ACQ FOR 40 PEAKUP Comments: STEPTIME=1.0S ------------------------------------------------------------------------------------------------------------------------------------ 40 SK-65D21 HRS RAPID 0.25 G140L 1400 SAMPLE-TIME=1.0 1 112.5M 1 SPATIAL SCAN SINGLE-EXP Comments: 15X15 GRID WITH 0.053 ARC SEC SPACING EXPTIME AT EACH DWELL POINT=30S ------------------------------------------------------------------------------------------------------------------------------------ Scan Paramters Form Proposal ID: 5745 [ 5] ------------------------------------------------------------------------------------------------------------------------------------ Data ID: 1 Exposure Logsheet lines: 40 FGS Scan: DWELL Dwell Only: dwell points/line: 15 Seconds per dwell: 30.00 Scan width (arc-secs): 0.7420 Scan length (arc-secs): 0.7420 Angle between sides (degrees) 270.00 Number of lines: 15 Scan rate (arc-sec/sec): 0.0000 PA of first scan line (degrees) 90.000 Scan frame (CEL or S/C): S/C Length Offset (arc-sec): 0.3710 Width Offset (arc-sec): 0.3710 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 5745 [ 6] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HRS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ IMAGE ACQ/PEAKUP RAPID ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SEARCH-SIZE=5 BRIGHT=RETURN NX=16 NY=16 DELTA-X=4 DELTA-Y=4 SAMPLE-TIME=1.0 ------------------------------------------------------------------------------------------------------------------------------------ Proposal for CAL/HRS ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 2.99 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category CALIBRATION ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 15-20; CYCLE 4 / 10-40 ONBOARD ACQ FOR 25 ONBOARD ACQ FOR 40 SPATIAL SCAN SINGLE-EXP ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR-N1 G140L ------------------------------------------------------------------------------------------------------------------------------------ Target Names SK-65D21 WO-39 ------------------------------------------------------------------------------------------------------------------------------------