9173( 3) - 02/21/01 15:20 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 9173 Version: 3 Check-in Date: 21-Feb-2001 15:19:09 1.Proposal Title: The Pattern of Heavy Element Abundances in a Damped LyAlpha Galaxy ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 10 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Jill Bechtold University of Arizona CoI: Dr. Aneta Siemiginowska Harvard-Center for Astrophysics N CoI: Dr. Thomas Aldcroft Harvard-Center for Astrophysics N CoI: Dr. Martin Elvis Harvard-Center for Astrophysics N CoI: Dr. Adam Dobrzycki Harvard-Center for Astrophysics N ------------------------------------------------------------------------------------ 5. Abstract We propose to observe the quasar PKS 1127-143 (z=1.18) with the STIS E230M. We have detected X-ray absorption associated with an intervening 21-cm and damped LyAlpha$ absorber at z=0.312 in its spectrum with Chandra. The advantage of the X- ray measurement is that the derived metallicity is insensitive to ionization, inclusion of an atom in a molecule, or depletion onto grains. The X-ray absorption is mostly due to oxygen, and the abundance agrees with the oxygen abundance of 16-40\ lines in a galaxy at the redshift of the absorber. The STIS spectrum will allow us to measure Zn II, an undepleted iron peak element. Comparison of the oxygen group measured in the X-rays with the iron peak nuclei measured by STIS will reveal whether the absorber has a Pop II, halo-type abundance pattern or a Pop I, disk-like abundance pattern. We also request a deep WFPC image so that we can characterize the morphology of the absorbing galaxy. ------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 2] Observations Description ------------------------ underline STIS Spectroscopy. We propose to use the E230M cross-dispersed echelle to search for Zn II LambdaLambda 2025, 2062. We can estimate how strong the lines will be from our estimates for the metallicity of the absorber. If Zn II is on the linear part of the curve of growth, and the gas has 1/5 solar Pop I abundances, then the observed equivalent widths of the Zn II lines will be 0.093 and 0.183 Angstrom, respectively. If the oxygen group has Pop II abundances, then the Zn II lines will be 3 times weaker. In the existing FOS spectrum, the 3.5Sigma equivalent width limit for line detection is 0.46 Angstrom at the position of these lines, so it is not surprising that they are not detected. The G230L grating on STIS does not have good enough spectral resolution to detect these lines in a reasonable exposure time. Instead we propose to use the E230M. From our simulations, we estimate that S/N=10 will be required to detect Zn II and distinguish between the disk and halo abundance patterns. In addition, the spectrum will cover Lambda=2310-3110 Angstrom observed, or 1760-2370Angstrom in the rest frame of the absorber, and so we expect to see other lines of interest, including lines of depleted elements such as Si II, Mn II, Cr II, Fe II and Ni II. PKS 1127-145 has 52 minutes of visibility per orbit. With guide star acquisition and instrument overheads we estimate that we would obtain 12, 240 seconds per 5 orbit visit. In 20 orbits, we obtain 48, 960 seconds of exposure, which, using the ETC and observed FOS flux level at Zn II of 2times10^-15 ergs s^-1 cm^-2 Angstrom ^-1, will give us a signal-to-noise of 10.4. \medskip underline WFPC Imaging. We require a deep image to resolve the morphology of the galaxies at z=0.312. The 3 galaxies with spectroscopic redshifts have m_AB=22.6, 22.2 and 19.8 at R 25, 27. Fainter galaxies appear to be present in ground- based images. We estimate, scaling from the image described in 31 of galaxies at similar redshift, that 10 orbits with the F702W are required to give detailed morphological information about these faint galaxies. Real Time Justification ----------------------- None. None. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 PKS1127-145 Galaxy, QUASAR RA=11H 30M 07.05S +/- 0S, DEC=- J2000.0 V = 16.9 14D 49' 27.00" +/- 0", PLATE- B-V = -0.5 ID=02MF Coordinate Source: GSC_SURVEY_PLATE Comments: Variable quasar 9173( 3) - 02/21/01 15:20 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFPC2-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.559017 Coordinate_Frame POS-TARG Pattern_Orient 26.565051 Center_Pattern YES ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 5] 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PKS1127-145 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 1.0 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PKS1127-145 STIS/C ACQ/PEA 0.2X0.2 MIRROR 1 1.0 S CD K ------------------------------------------------------------------------------------------------------------------------------------ 3 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 1 32.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 4 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 2 42.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 6] Visit: 02 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PKS1127-145 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 1.0 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PKS1127-145 STIS/C ACQ/PEA 0.2X0.2 MIRROR 1 1.0 S CD K ------------------------------------------------------------------------------------------------------------------------------------ 3 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 1 32.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 4 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 2 42.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 7] Visit: 03 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PKS1127-145 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 1.0 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PKS1127-145 STIS/C ACQ/PEA 0.2X0.2 MIRROR 1 1.0 S CD K ------------------------------------------------------------------------------------------------------------------------------------ 3 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 1 32.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 4 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 2 42.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 8] Visit: 04 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PKS1127-145 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 1.0 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PKS1127-145 STIS/C ACQ/PEA 0.2X0.2 MIRROR 1 1.0 S CD K ------------------------------------------------------------------------------------------------------------------------------------ 3 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 1 32.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 4 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 2 42.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 9] Visit: 05 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PKS1127-145 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 1.0 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PKS1127-145 STIS/C ACQ/PEA 0.2X0.2 MIRROR 1 1.0 S CD K ------------------------------------------------------------------------------------------------------------------------------------ 3 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 1 32.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 4 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 2 42.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 10] Visit: 06 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PKS1127-145 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 1.0 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PKS1127-145 STIS/C ACQ/PEA 0.2X0.2 MIRROR 1 1.0 S CD K ------------------------------------------------------------------------------------------------------------------------------------ 3 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 1 32.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 4 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 2 42.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 11] Visit: 07 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 PKS1127-145 STIS/C ACQ F28X50L MIRROR ACQTYPE=POINT 1 1.0 S CD P ------------------------------------------------------------------------------------------------------------------------------------ 2 PKS1127-145 STIS/C ACQ/PEA 0.2X0.2 MIRROR 1 1.0 S CD K ------------------------------------------------------------------------------------------------------------------------------------ 3 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 1 32.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 4 PKS1127-145 STIS/N ACCUM 0.2X0.2 E230M 2707 1 42.0 M UV-MAM A ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 12] Visit: 08 Visit Priority: Visit Requirements: ORIENT 300.0D TO 330.0D 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 PKS1127-145 WFPC2 IMAGE WF3 F814W ATD-GAIN=7,CR-SPLIT=NO 1 1105.0 Pattern 1 Comments: Setting up 5 visits, Different Orient to control blooming direction, small offset to randomize dither pattern. ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 13] Visit: 09 Visit Priority: Visit Requirements: ORIENT 125.0D TO 150.0D 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 PKS1127-145 WFPC2 IMAGE WF3 F814W ATD-GAIN=7,CR-SPLIT=NO 1 1105.0 Pattern 1; POS TARG -3.5, 1.5 ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 14] Visit: 10 Visit Priority: Visit Requirements: ORIENT 90.0D TO 125.0D 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 PKS1127-145 WFPC2 IMAGE WF3 F814W ATD-GAIN=7,CR-SPLIT=NO 1 1105.0 Pattern 1; POS TARG 1.5, -4. ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 15] Visit: 11 Visit Priority: Visit Requirements: ORIENT 270.0D TO 300.0D 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 PKS1127-145 WFPC2 IMAGE WF3 F814W ATD-GAIN=7,CR-SPLIT=NO 1 1105.0 Pattern 1; POS TARG 0, -3.5 ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 16] Visit: 12 Visit Priority: Visit Requirements: ORIENT 270.0D TO 300.0D 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 PKS1127-145 WFPC2 IMAGE WF3 F814W ATD-GAIN=7,CR-SPLIT=NO 1 1105.0 Pattern 1; POS TARG 0, -1.5 ------------------------------------------------------------------------------------------------------------------------------------ 9173( 3) - 02/21/01 15:20 - [ 17] Summary Form for Proposal 9173 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures F28X50LP 0.2X0.2 WF3 ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD STIS/NUV-MAMA WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACQ/PEAK ACCUM IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ACQTYPE=POINT CR-SPLIT=NO ATD-GAIN=7 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 300.0D TO 330.0D Pattern 1 ORIENT 125.0D TO 150.0D Pattern 1; POS TARG -3.5, 1.5 ORIENT 90.0D TO 125.0D Pattern 1; POS TARG 1.5,-4. ORIENT 270.0D TO 300.0D Pattern 1; POS TARG 0,-3.5 Pattern 1; POS TARG 0,-1.5 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR E230M F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names PKS1127-145 ------------------------------------------------------------------------------------------------------------------------------------ Wavelengths 2707 ------------------------------------------------------------------------------------------------------------------------------------