7296( 7) - 03/12/98 00:13 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 7296 Version: 7 Check-in Date: 12-Mar-1998 00:11:26 1.Proposal Title: A STIS Probe of Unique ISM Lines-of-Sight Having Measured H and He Ionization Fractions ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 7 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: JAY B. HOLBERG UNIVERSITY OF ARIZONA CoI: M. A. Barstow University of Leicester N CoI: F. C. Bruhweiler Catholic University of America Y CoI: P.D. Dobbie University of Leicester N ------------------------------------------------------------------------------------ 5. Abstract We propose to use the STIS E140H grating to obtain high S/N (>15:1) far UV spectra of the lines-of-sight to five white dwarfs where the ISM H and He ionization fractions have now been measured with EUVE. We seek to determine: 1) The number of and column densities of ISM components along each line-of- sight; 2) the ionization state and abundances of, important elements such as C, N and Si for these lines-of- sight. Our EUVE analyses of these stars (Barstow et al. 1996) are consistent with the fundamental conclusion that the respective H and He ionization fractions are 0.27 +/- 0.04 and 0.35 +/- 0.1 in all five directions. These observations also demonstrate that much of the EUV absorption is due to ISM components beyond the local cloud containing the sun. STIS data are required to independently access the homogeneity of these lines-of-sight and to verify that they support the conclusion of uniform H and He ionization the Local ISM. ------------------------------------------------------------------------------------ 7296( 7) - 03/12/98 00:13 - [ 2] Observations Description ------------------------ Each of the five targets is to be observed once using the E140H grating at the 1271 Angstrom\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ secondary setting and the 0.2arcs x 0.2arcs slit. The two brightest targets (WD2309+105 and WD0050- 332) are to be observed at S/N (30:1), which will require two orbits each. PG 1123+189 will also be observed for two orbits at S/N (20:1). The remaining two fainter stars (RE1032+535 and RE2156-546) are of equal brightness and are both in the CVZ. We can achieve (S/N = 15) in 1 CVZ orbit for each. Real Time Justification ----------------------- Two targets, RE1032+535 and RE2156-546 are in the Continuous Viewing Zone (CVZ). Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: ELECTRONIC Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 7296( 7) - 03/12/98 00:13 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 WD0050-332 ISM,ABSORPTION LINE RA=00H 53M 17.34S +/- 0.5S,DEC=- J2000 V = 13.36+/-0.02 SYSTEM - 32D 59' 57.5" +/- 0.5",PLATE- B-V = -0.23+/-0.02 GALACTIC,STAR,DA ID=024K F-CONT(1270)=2.2+/-0.1e-12 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B1982.64 -0.00243 0.0116 0.016 2 WD2309+105 ISM,ABSORPTION LINE RA=23H 12M 21.50S +/- J2000 V = 13.09+/-0.01 SYSTEM - 0.5S,DEC=10D 47' 4.83" +/- B-V = -0.32+/-.01 GALACTIC,STAR,DA 0.5",PLATE-ID=00JE F-CONT(1270)=3.87+/-0.2e-12 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B1982.794 0.0016 -0.0112 0.0134 3 2REJ1032+532 ISM,ABSORPTION LINE RA=10H 32M 10.07S +/- J2000 V = 14.455+/-0.02 SYSTEM - 0.5S,DEC=53D 29' 35.58" +/- B-V = -0.276+/-0.02 GALACTIC,STAR,DA 0.5",PLATE-ID=01RP F-CONT(1270)=9.64+/-0.5e-13 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B1984.976 0.0 0.0 0.0 4 WD1123+183 ISM,ABSORPTION LINE RA=11H 26M 19.12S +/- J2000 V = 14.13+/-0.03 SYSTEM - 0.5S,DEC=18D 39' 16.88" +/- B-V = -0.28+/-0.02 GALACTIC,STAR,DA 0.5",PLATE-ID=01TO F-CONT(1270)=1.46+/-0.07e-12 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B1985.050 0.0 0.0 0.0 5 2REJ2156-543 ISM,ABSORPTION LINE RA=21H 56M 21.17S +/- 0.5S,DEC=- J2000 V = 14.44+/-0.02 SYSTEM - 54D 38' 23.2" +/- 0.5",PLATE- B-V = -0.23+/-0.02 GALACTIC,STAR,DA ID=02AB F-CONT(1270)=9.80+/-0.5e-13 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B1978.80 0.0 0.0 0.0 7296( 7) - 03/12/98 00:13 - [ 4] Visit: 01 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: 1. E140H total exposure = 4053 s anticipated S/N=23 at 1271A, ISM lines <1350 + NV Circumstellar Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WD0050-332 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.1 S ONBOARD ACQ FOR 2 CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 WD0050-332 STIS/C ACQ/PEA 0.2X0.0 MIRROR 1 1 S ONBOARD ACQ FOR 3 CD K 9 ------------------------------------------------------------------------------------------------------------------------------------ 3 WD0050-332 STIS/F ACCUM 0.2X0.0 E140H 1271 1 36 M SAA-CONTOUR 24 UV-MAM 9 A ------------------------------------------------------------------------------------------------------------------------------------ 4 WD0050-332 STIS/C ACQ/PEA 0.2X0.0 MIRROR 1 1 S ONBOARD ACQ FOR 5 CD K 9 ------------------------------------------------------------------------------------------------------------------------------------ 5 WD0050-332 STIS/F ACCUM 0.2X0.0 E140H 1271 1 36 M SAA-CONTOUR 24 UV-MAM 9 A ------------------------------------------------------------------------------------------------------------------------------------ 7296( 7) - 03/12/98 00:13 - [ 5] Visit: 02 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: 1. E140H total exposure = 2374s and anticipated S/N = 22.4 at 1271 A, ISM lines <1350A + NV Stellar lines. 2. E140M total exposure = 1666s and anticipated S/N = 26 at 1425 A, ISM lines <1700A + NV,SiIV & CIV Stellar lines. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WD2309+105 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.1 S ONBOARD ACQ FOR 2 CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 WD2309+105 STIS/C ACQ/PEA 0.2X0.0 MIRROR 1 1 S ONBOARD ACQ FOR 3 CD K 9 ------------------------------------------------------------------------------------------------------------------------------------ 3 WD2309+105 STIS/F ACCUM 0.2X0.0 E140M 1425 1 30 M SAA-CONTOUR 24 UV-MAM 9 A ------------------------------------------------------------------------------------------------------------------------------------ 4 WD2309+105 STIS/C ACQ/PEA 0.2X0.0 MIRROR 1 1 S ONBOARD ACQ FOR 5 CD K 9 ------------------------------------------------------------------------------------------------------------------------------------ 5 WD2309+105 STIS/F ACCUM 0.2X0.0 E140H 1271 1 38 M SAA-CONTOUR 24 UV-MAM 9 A ------------------------------------------------------------------------------------------------------------------------------------ 7296( 7) - 03/12/98 00:13 - [ 6] Visit: 03 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: E140M total exposure = 2138s anticipated S/N = 14.5 at 1425A, ISM lines <1700A. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 2REJ1032+53 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.2 S ONBOARD ACQ FOR 2 2 CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 2REJ1032+53 STIS/C ACQ/PEA 0.2X0.0 MIRROR 1 3 S ONBOARD ACQ FOR 3 2 CD K 9 ------------------------------------------------------------------------------------------------------------------------------------ 3 2REJ1032+53 STIS/F ACCUM 0.2X0.0 E140M 1425 1 33 M 2 UV-MAM 9 A ------------------------------------------------------------------------------------------------------------------------------------ 7296( 7) - 03/12/98 00:13 - [ 7] Visit: 04 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: E140H total exposurte time = 3957s anticipated S/N = 18 at 1271A, ISM lines <1350A. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 WD1123+183 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.1 S ONBOARD ACQ FOR 2 CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 WD1123+183 STIS/C ACQ/PEA 0.2X0.0 MIRROR 1 1 S ONBOARD ACQ FOR 3 CD K 9 ------------------------------------------------------------------------------------------------------------------------------------ 3 WD1123+183 STIS/F ACCUM 0.2X0.0 E140H 1271 1 35 M SAA-CONTOUR 24 UV-MAM 9 A ------------------------------------------------------------------------------------------------------------------------------------ 4 WD1123+183 STIS/C ACQ/PEA 0.2X0.0 MIRROR 1 1 S ONBOARD ACQ FOR 5 CD K 9 ------------------------------------------------------------------------------------------------------------------------------------ 5 WD1123+183 STIS/F ACCUM 0.2X0.0 E140H 1271 1 35 M SAA-CONTOUR 24 UV-MAM 9 A ------------------------------------------------------------------------------------------------------------------------------------ 7296( 7) - 03/12/98 00:13 - [ 8] Visit: 05 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: E140M total exposure time = 2138s anticipated S/N = 14.5 at 1425A, ISM lines <1700A. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 2REJ2156-54 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.2 S ONBOARD ACQ FOR 2 3 CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 2REJ2156-54 STIS/C ACQ/PEA 0.2X0.0 MIRROR 1 3 S ONBOARD ACQ FOR 3 3 CD K 9 ------------------------------------------------------------------------------------------------------------------------------------ 3 2REJ2156-54 STIS/F ACCUM 0.2X0.0 E140M 1425 1 33 M SAA-CONTOUR 24 3 UV-MAM 9 A ------------------------------------------------------------------------------------------------------------------------------------ 7296( 7) - 03/12/98 00:13 - [ 9] Summary Form for Proposal 7296 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD STIS/FUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACQ/PEAK ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ACQTYPE=POINT ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 2 ONBOARD ACQ FOR 3 SAA-CONTOUR 24 ONBOARD ACQ FOR 5 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR E140H E140M ------------------------------------------------------------------------------------------------------------------------------------ Target Names WD0050-332 WD2309+105 2REJ1032+532 WD1123+183 2REJ2156-543 ------------------------------------------------------------------------------------------------------------------------------------