8571( 2) - 08/30/00 10:41 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8571 Version: 2 Check-in Date: 01-Feb-2000 14:56:41 1.Proposal Title: Metallicity and D/H abundance in Low-z LyAlpha Absorbers towards PG 1211+143 ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 9 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: J. Shull University of Colorado at Boulder CoI: Dr. John Stocke University of Colorado, Boulder N CoI: Dr. Steven Penton University of Colorado, Boulder N CoI: Dr. Mark Giroux University of Colorado, Boulder N CoI: Dr. Brad Gibson University of Colorado, Boulder N ------------------------------------------------------------------------------------ 5. Abstract Our Cycle 7 STIS/G140M observations along the sightline toward PG 1211+143 reveal numerous LyAlpha absorption lines including 2 very strong LyAlpha absorbers (cz = 15, 300 and 19, 550 km s^- 1) with associated Si III absorption. These are the first definite detections of metals in a low-z LyAlpha forest cloud; simple photoionization models suggest metallicities in the range 1--10\ sim10^17 cm^-2 in each system, we should be able to detect deuterium LyAlpha at 10--20 mAngstrom\ equivalent width, thereby testing models of D/H astration as a function of IGM metallicity, an issue of cosmological significance. We propose to obtain a 25-orbit (S/N ~ 25) STIS/E140M spectrum (1150-1740 Angstrom) at 10 km s^-1 resolution to detect or limit D I (LyAlpha) and to measure metal absorption lines (C IV, Si IV, N V, C II, Si II) observable down to below 10^-2 solar abundance (4 mAngstrom\ EW limit). This sightline is one of two prime FUSE targets for long-duration exposures in the extragalactic D/H program. FUSE will detect higher Ly-series lines and the Lyman break (accurate H I column density) and measure key metal lines (C III Lambda977, O VI Lambda1032, 1038). Thus, the FUSE and STIS programs are highly interdependent. ------------------------------------------------------------------------------------ 8571( 2) - 08/30/00 10:41 - [ 2] Observations Description ------------------------ We propose to obtain a 25-orbit exposure (totaling 1060 minutes) of PG 1211+143 with the STIS/E140M echelle (1150- 1740 Angstrom) taken through the 0.2'' * 0.2'' slit. In the spectral region of interest for deuterium (1275-1295 Angstrom) this exposure should provide S/N ~ 25 per 0.0145 Angstrom\ resolution element, adequate to detect the weak D I features. We will also measure or limit metal-ion absorption from C IV, Si IV, Si II, and C II at 4Sigma significance down to 4 mAngstrom\ equivalent width. The S/N estimates are based on the STIS Exposure Time Calculator simulator, using the median flux level, F_Lambda = 4 * 10^-14 ergs cm^-2 s^-1 AA^-1 at 1280 Angstrom\ from the Penton & Shull (1999) IUE- AGN database. Our previous STIS observation, shown in Fig. 1, had a flux 20\ above the IUE long-term average. However, between 1980 and 1992, PG1211+143 ranged in flux from (3-5) * 10^-14, so our choice of F_Lambda = 4* 10^-14 was made conservatively in order to achieve the S/N needed for our science goals: the detection of weak lines of D I and key heavy elements. Real Time Justification ----------------------- None. We will conduct deep 21-cm VLA images at 15, 300 and 19, 550 km s^-1 to identify H I galaxies in the field. We have used the same technique toward several of our previous GHRS and STIS targets (van Gorkom et al.\ 1996; Shull et al.\ 1998). The digitized sky survey images show a rich field of galaxies within +/-12' of PG1211+143, including two bright galaxies at cz ~ 0.051 (near one of the strong LyAlpha absorbers) offset from the sightline by 102h^-1 and 295h^-1 kpc. The nearer of these galaxies was missing from the list given by Bowen et al. (1996). Our group (Stocke, McLin) has proposed to conduct a deep spectroscopic survey of this region with WIYN/HYDRA. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 8571( 2) - 08/30/00 10:41 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 PG1211+143 GALAXY, Quasar, Lyman RA=12H 14M 17.66S +/- 0.1S, J2000 Z=0.085 V = 14.63 Alpha Cloud DEC=14D 03' 12.02" +/- 1.0", B-V = 0.5 PLATE-ID=01TJ Coordinate Source: GSC_SURVEY_PLATE Comments: 25 orbits, PLATE-ID=01TJ 8571( 2) - 08/30/00 10:41 - [ 4] Visit: 01 Visit Priority: Visit Requirements: GROUP 1-8 WITHIN 90D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PG1211+143 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.3 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 1 2418.0 EXPAND UV-MAM A Comments: First orbit exposure short due to overheads ------------------------------------------------------------------------------------------------------------------------------------ 3 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 3 2899.0 EXPAND UV-MAM A Comments: Three orbit exposure ------------------------------------------------------------------------------------------------------------------------------------ 8571( 2) - 08/30/00 10:41 - [ 5] Visit: 02 Visit Priority: Visit Requirements: GROUP 1-8 WITHIN 90D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PG1211+143 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.3 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 1 2418.0 EXPAND UV-MAM A Comments: First orbit exposure short due to overheads ------------------------------------------------------------------------------------------------------------------------------------ 3 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 2 2899.0 EXPAND UV-MAM A Comments: Two orbit exposure ------------------------------------------------------------------------------------------------------------------------------------ 8571( 2) - 08/30/00 10:41 - [ 6] Visit: 03 Visit Priority: Visit Requirements: GROUP 1-8 WITHIN 90D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PG1211+143 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.3 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 1 2418.0 EXPAND UV-MAM A Comments: First orbit exposure short due to overheads ------------------------------------------------------------------------------------------------------------------------------------ 3 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 2 2899.0 EXPAND UV-MAM A Comments: Two orbit exposure ------------------------------------------------------------------------------------------------------------------------------------ 8571( 2) - 08/30/00 10:41 - [ 7] Visit: 04 Visit Priority: Visit Requirements: GROUP 1-8 WITHIN 90D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PG1211+143 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.3 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 1 2418.0 EXPAND UV-MAM A Comments: First orbit exposure short due to overheads ------------------------------------------------------------------------------------------------------------------------------------ 3 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 2 2899.0 EXPAND UV-MAM A Comments: Two orbit exposure ------------------------------------------------------------------------------------------------------------------------------------ 8571( 2) - 08/30/00 10:41 - [ 8] Visit: 05 Visit Priority: Visit Requirements: GROUP 1-8 WITHIN 90D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PG1211+143 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.3 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 1 2418.0 EXPAND UV-MAM A Comments: First orbit exposure short due to overheads ------------------------------------------------------------------------------------------------------------------------------------ 3 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 2 2899.0 EXPAND UV-MAM A Comments: Two orbit exposure ------------------------------------------------------------------------------------------------------------------------------------ 8571( 2) - 08/30/00 10:41 - [ 9] Visit: 06 Visit Priority: Visit Requirements: GROUP 1-8 WITHIN 90D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PG1211+143 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.3 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 1 2418.0 EXPAND UV-MAM A Comments: First orbit exposure short due to overheads ------------------------------------------------------------------------------------------------------------------------------------ 3 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 2 2899.0 EXPAND UV-MAM A Comments: Two orbit exposure ------------------------------------------------------------------------------------------------------------------------------------ 8571( 2) - 08/30/00 10:41 - [ 10] Visit: 07 Visit Priority: Visit Requirements: GROUP 1-8 WITHIN 90D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PG1211+143 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.3 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 1 2418.0 EXPAND UV-MAM A Comments: First orbit exposure short due to overheads ------------------------------------------------------------------------------------------------------------------------------------ 3 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 2 2899.0 EXPAND UV-MAM A Comments: Two orbit exposure ------------------------------------------------------------------------------------------------------------------------------------ 8571( 2) - 08/30/00 10:41 - [ 11] Visit: 08 Visit Priority: Visit Requirements: GROUP 1-8 WITHIN 90D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PG1211+143 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 0.3 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 1 2418.0 EXPAND UV-MAM A Comments: First orbit exposure short due to overheads ------------------------------------------------------------------------------------------------------------------------------------ 3 PG1211+143 STIS/F ACCUM 0.2X0.2 E140M 1425 2 2899.0 EXPAND UV-MAM A Comments: Two orbit exposure ------------------------------------------------------------------------------------------------------------------------------------ 8571( 2) - 08/30/00 10:41 - [ 12] Summary Form for Proposal 8571 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures F28X50LP 0.2X0.2 ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD STIS/FUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ACQTYPE=POINT ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GROUP 1-8 WITHIN 90D EXPAND ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR E140M ------------------------------------------------------------------------------------------------------------------------------------ Target Names PG1211+143 ------------------------------------------------------------------------------------------------------------------------------------ Wavelengths 1425 ------------------------------------------------------------------------------------------------------------------------------------