7366( 3) - 04/20/98 09:08 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 7366 Version: 3 Check-in Date: 20-Apr-1998 09:06:47 1.Proposal Title: Intense Galactic X-ray Sources in Crowded Fields ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 7 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Dr. Bruce Margon University of Washington CoI: Stefanie Wachter University of Washington N CoI: Scott Anderson University of Washington Y ------------------------------------------------------------------------------------ 5. Abstract We discuss two intense, well-studied galactic X-ray binary stars with low-mass companions: GX17+2 and Circinus X-1. Both sources lie in severely optically crowded fields, and there is strong evidence that past work has been deceived by spurious superpositions of unrelated objects. HST NICMOS imaging and spectra will be used to elucidate the nature of the sources, each of which is an important member of its class, yet poorly understood. This proposal is a follow-on to a similar, set of observations we executed in GO Cycle 5, where a previously unsuspected, and important, superposition was indeed discovered. ------------------------------------------------------------------------------------ 7366( 3) - 04/20/98 09:08 - [ 2] Observations Description ------------------------ For NP-SER=GX17+2, we are using NICMOS to search for a very close superposition of sources, and require the high resolution of Camera 1. In addition, we are trying to detect a faint companion next to a bright (H=14.5) star and will take advantage of the increased dynamic range offered by the MULTIACCUM readout. F110W and F16W images are taken to achieve, S/N>20 at H=20. MULTIACCUM exposures will achieve the needed depth, while still permitting phomomtery of the bright star in the shorter accumulated exposures. Multiple dithers are taken to limit bad pixels, flatfield uncertainties, etc. For BR Cir = Cir X-1 our aim is NICMOS spectroscopy with all three grisms. The object is variable, but usually has J>13.7, H>12.5, K>12.0. As recommended, we will obtain images of the field in the appropriate filter corresponding to each grism, with an exposure time of 1s sufficient in each filter (F110W, F150W, F175W). Combined exposure times should attain S/N>50 for each grism. With G206, exposure times are limited to about 10s each to avoid saturating the detector due to the thermal background. Multiple dithers are used to account for bad pixels, cosmic rays and flat fielding. Real Time Justification ----------------------- None Calibration Justification ------------------------- None Additional Comments ------------------- None ------------------------------------------------------------------------------------ Data Distribution Media: ELECTRONIC Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 7366( 3) - 04/20/98 09:08 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 NP-SER STAR,LMXB RA=18H 16M 01.44S +/- 0.1S, DEC= 2000 V = 17.5+/-1.0 -14D 02' 12.5" +/- 1.0", PLATE- ID=064B 2 BR-CIR STAR,MXB RA=15H 20M 40.86S +/- 0.1S, DEC= 2000 V = 21.4+/-1.0 -57D 09' 59.8" +/- 1.0", PLATE- ID=00H6 Comments: Coordinates from earlier HST proposal 5697 7366( 3) - 04/20/98 09:08 - [ 4] Visit: 01 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 101 NP-SER NIC1 MULTIAC NIC1 F110W SAMP-SEQ=STEP16,NSAMP=12, 1 DEF CUM PATTERN=SPIRAL-DITH,NUM-POS=5, DITH-SIZE=1.29 ------------------------------------------------------------------------------------------------------------------------------------ 102 NP-SER NIC1 MULTIAC NIC1 F160W SAMP-SEQ=STEP16,NSAMP=25, 1 DEF CUM PATTERN=SPIRAL-DITH,NUM-POS=5, DITH-SIZE=1.29 ------------------------------------------------------------------------------------------------------------------------------------ 7366( 3) - 04/20/98 09:08 - [ 5] Visit: 02 Visit Priority: Visit Requirements: ORIENT 35D TO 55D On Hold Comments: Additional Comments: Need grism dispersion aligned nearly East-West, to avoid overlaps. PC/Instr scientist: please verify that requested ORIENT is appropriate for East-West. ORIENT could also be 180 degrees different than that specified above (ORIENT 215D TO 235D OK too). Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 201 BR-CIR NIC3 ACCUM NIC3 F110W NREAD=1,PATTERN=SPIRAL-DITH, 1 1.035 S PAR 202-203 WITH 201 NUM-POS=5,DITH-SIZE=10.0 ------------------------------------------------------------------------------------------------------------------------------------ 202 ANY NIC1 ACCUM NIC1 F110W NREAD=1 1 1.035 S ------------------------------------------------------------------------------------------------------------------------------------ 203 ANY NIC2 ACCUM NIC2 F237M NREAD=1 1 1.035 S ------------------------------------------------------------------------------------------------------------------------------------ 204 BR-CIR NIC3 ACCUM NIC3 G096 NREAD=9,PATTERN=SPIRAL-DITH, 1 57.534 PAR 205-206 WITH 204 NUM-POS=5,DITH-SIZE=10.0 ------------------------------------------------------------------------------------------------------------------------------------ 205 ANY NIC1 ACCUM NIC1 F110W NREAD=9 1 57.534 ------------------------------------------------------------------------------------------------------------------------------------ 206 ANY NIC2 ACCUM NIC2 F237M NREAD=9 1 57.534 ------------------------------------------------------------------------------------------------------------------------------------ 207 BR-CIR NIC3 ACCUM NIC3 F150W NREAD=1,PATTERN=SPIRAL-DITH, 1 1.035 S PAR 208-209 WITH 207 NUM-POS=5,DITH-SIZE=10.0 ------------------------------------------------------------------------------------------------------------------------------------ 208 ANY NIC1 ACCUM NIC1 F160W NREAD=1 1 1.035 S ------------------------------------------------------------------------------------------------------------------------------------ 209 ANY NIC2 ACCUM NIC2 F237M NREAD=1 1 1.035 S ------------------------------------------------------------------------------------------------------------------------------------ 210 BR-CIR NIC3 ACCUM NIC3 G141 NREAD=9,PATTERN=SPIRAL-DITH, 1 35.356 PAR 211-212 WITH 210 NUM-POS=5,DITH-SIZE=10.0 ------------------------------------------------------------------------------------------------------------------------------------ 211 ANY NIC1 ACCUM NIC1 F160W NREAD=9 1 35.356 ------------------------------------------------------------------------------------------------------------------------------------ 212 ANY NIC2 ACCUM NIC2 F237M NREAD=9 1 35.356 ------------------------------------------------------------------------------------------------------------------------------------ 213 BR-CIR NIC3 ACCUM NIC3 F175W NREAD=1,PATTERN=SPIRAL-DITH, 1 1.035 S PAR 214-215 WITH 213 NUM-POS=5,DITH-SIZE=10.0 ------------------------------------------------------------------------------------------------------------------------------------ 214 ANY NIC1 ACCUM NIC1 F160W NREAD=1 1 1.035 S ------------------------------------------------------------------------------------------------------------------------------------ 215 ANY NIC2 ACCUM NIC2 F237M NREAD=1 1 1.035 S ------------------------------------------------------------------------------------------------------------------------------------ 216 BR-CIR NIC3 ACCUM NIC3 G206 NREAD=1,PATTERN=SPIRAL-DITH, 5 10.597 PAR 217-218 WITH 216 NUM-POS=5,DITH-SIZE=10.0 ------------------------------------------------------------------------------------------------------------------------------------ 217 ANY NIC1 ACCUM NIC1 F160W NREAD=1 5 10.597 ------------------------------------------------------------------------------------------------------------------------------------ 218 ANY NIC2 ACCUM NIC2 F237M NREAD=1 5 10.597 ------------------------------------------------------------------------------------------------------------------------------------ 7366( 3) - 04/20/98 09:08 - [ 6] Summary Form for Proposal 7366 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations NIC1 NIC3 NIC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SAMP-SEQ=STEP16 NSAMP=12 PATTERN=SPIRAL-DITH NUM-POS=5 DITH-SIZE=1.29 NSAMP=25 DITH-SIZE=10.0 NREAD=1 NREAD=9 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 35D TO 55D PAR 202-203 WITH 201 PAR 205-206 WITH 204 PAR 208-209 WITH 207 PAR 211-212 WITH 210 PAR 214-215 WITH 213 PAR 217-218 WITH 216 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F110W F160W F237M G096 F150W G141 F175W G206 ------------------------------------------------------------------------------------------------------------------------------------ Target Names NP-SER BR-CIR ANY ------------------------------------------------------------------------------------------------------------------------------------