Assigned ID: 1051 ----- Attempting Submission 1 (Sat Feb 27 02:41:47 GMT 2010) ----- HST Phase I Proposal 1051 (prop.apt) successfully submitted. ----- Attempting Submission 2 (Sat Feb 27 02:46:57 GMT 2010) ----- HST Phase I Proposal 1051 (prop.apt) successfully submitted. ----- Attempting Submission 3 (Sat Feb 27 03:09:15 GMT 2010) ----- ----- Attempting Submission 1 (Fri Jul 09 20:49:42 GMT 2010) ----- Cosmic Metallicity from ZnII-Selected QSO Absorption Line Systems Near Redshift z=1.2 We have searched nearly 15,000 strong intervening MgII systems in SDSS quasar spectra to measure spectral regions where weak, unsaturated metal lines are predicted to exist, with the aim of finding a representative sample of the strongest metal-line column density systems in the universe. These systems are clearly damped Lyman-alpha (DLA) systems, which track cosmologically intervening neutral gas regions that fall along the sightlines to background quasars. We propose STIS G230L spectroscopy of seven strong-ZnII-selected systems from this sample in order to measure their Lyman-alpha absorption profiles and derive their HI column densities. Since Zn is not depleted onto grains, measurement of N(HI) allows a direct measurement of the metal abundance in such systems. We expect the results to be representative of the upper envelope of the distribution of neutral-gas-phase metallicities near redshift z=1.2. If these systems are high-N(HI) DLAs (e.g., 6E21 atoms/cm^2) they will have metallicities typical of those normally found in DLAs (e.g., one-tenth solar). However, if they are low-N(HI) DLAs (e.g., 2E20 atoms/cm$^2$), they will have supersolar metallicities. Since these DLAs are selected on the basis of their extreme metal-line properties, analysis of their metallicities and dust-to-gas ratios will lead to strong constraints on the range of properties exhibited by DLA systems.
All eight of our targets are QSOs with intervening absorption systems at z~1.2, and all have large Zn+ absorption column densities. All of the targets have Sloan (u,g,r,i,z) fluxes measured to within several percent; four of the eight targets also have GALEX NUV magnitudes available. On an f(lambda) scale, all of the SDSS spectra are seen to rise into the UV. The z_em and z_abs of the targets were selected such that there is no possibility that Lyman limit absorption near z_em can block observation of Ly-alpha at z_abs. We propose to observe the corresponding Ly-alpha absorption line in each system to measure their neutral column densities and thereby derive their metal abundances. Based on the ZnII measurements, these are the best candidates for supersolar metallicity DLAs. Results on Cr, Fe, Mn, and Si are also available. All of the observations will be made with the STIS G230L grating. To extrapolate into the UV and calculate exposure times we used the exposure time calculator (ETC). Based on archival spectra, we estimate that S/N=8 per resolution element is adequate for our measurements. We used the QSOs' GALEX NUV magnitudes (or the SDSS g values when NUV magnitudes were unavailable) and the SDSS/FOS quasar templates of the ETC to predict the exposure time necessary to achieve S/N=8 per resolution element. The Ly-alpha lines are expected to be damped, and therefore they will have very large absorption equivalent widths, which can be very easily measured with this S/N at this resolution. Given this requirement, the ETC values imply that 1-2 orbits are required per object. For the four single-orbit observations the S/N ratios will be higher. All eight observations will be made in the 52 x 0.2 arc sec slit, and will be CR-SPLIT to eliminate cosmic rays. The resolution will be R~500 with 1.58 Ang/pix and S/N~8 per resolution element, which is sufficient for measuring the column densities of the broad damped Ly-alpha lines to within an accuracy of <30% based on Voigt profile fits. This is possible because the DLA lines are not only strong but also resolved at the resolution of the STIS G230L gration. The coordinates are from SDSS and are in the ICRS frame. T QUASAR ABSORPTION LINES AND IGM 12 false 0.0 0.0 false false false false false false SUPPORTED GALAXY QSO J2000 09 53 24.5637 +63 51 3.05 J2000 GALAXY QSO J2000 08 31 57.7939 +36 35 53.05 J2000 GALAXY QSO J2000 13 53 9.4696 +03 33 28.08 J2000 GALAXY QSO 0254-0734 J2000 00 00 0.0000 +00 00 0.00 J2000 GALAXY QSO 1355+0042 J2000 00 00 0.0000 +00 00 0.00 J2000 GALAXY QSO 1205+3144 J2000 00 00 0.0000 +00 00 0.00 J2000 GALAXY QSO 1453+3136 J2000 00 00 0.0000 +00 00 0.00 J2000 GALAXY QSO 1204+0338 J2000 00 00 0.0000 +00 00 0.00 J2000 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/NUV-MAMA Spectroscopic No No G230L 2376 STIS/NUV-MAMA Spectroscopic No No G230L 2376 /home/eric/PROPOSALS/HST/CYCLE18/ZNII/PHASE2/OP-cache/GO12308phase2-v01.xml The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12308 :visit-id "01" :proposal-version -1 :trans-version "20100505" :date "09-Jul-2010 16:35:09.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 104848 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12308 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12308 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3183 :al-overhead-at-end 200 :internal-dur-at-end 321 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3516 :pcs-gap 0 ) true 1 0 Onboard ACQ for 2 /home/eric/PROPOSALS/HST/CYCLE18/ZNII/PHASE2/OP-cache/GO12308phase2-v02.xml The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12308 :visit-id "02" :proposal-version -1 :trans-version "20100505" :date "09-Jul-2010 16:35:11.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 104848 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12308 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12308 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2968 :al-overhead-at-end 200 :internal-dur-at-end 321 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3301 :pcs-gap 0 ) true 1 0 Onboard ACQ for 2 /home/eric/PROPOSALS/HST/CYCLE18/ZNII/PHASE2/OP-cache/GO12308phase2-v03.xml The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12308 :visit-id "03" :proposal-version -1 :trans-version "20100505" :date "09-Jul-2010 16:35:14.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 191856 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12308 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12308 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2901 :al-overhead-at-end 200 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) (Tic-Orbit :proposal-id 12308 :visit-id "03" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3012 :al-overhead-at-end 200 :internal-dur-at-end 321 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) true 2 0 /home/eric/PROPOSALS/HST/CYCLE18/ZNII/PHASE2/OP-cache/GO12308phase2-v04.xml The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12308 :visit-id "04" :proposal-version -1 :trans-version "20100505" :date "09-Jul-2010 16:35:16.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 104848 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12308 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12308 :visit-id "04" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2909 :al-overhead-at-end 200 :internal-dur-at-end 321 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3242 :pcs-gap 0 ) true 1 0 /home/eric/PROPOSALS/HST/CYCLE18/ZNII/PHASE2/OP-cache/GO12308phase2-v05.xml The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12308 :visit-id "05" :proposal-version -1 :trans-version "20100505" :date "09-Jul-2010 16:35:19.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 191856 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12308 :visit-id "05" :obset-id "05" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12308 :visit-id "05" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2901 :al-overhead-at-end 200 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) (Tic-Orbit :proposal-id 12308 :visit-id "05" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3012 :al-overhead-at-end 200 :internal-dur-at-end 321 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) true 2 0 /home/eric/PROPOSALS/HST/CYCLE18/ZNII/PHASE2/OP-cache/GO12308phase2-v06.xml The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12308 :visit-id "06" :proposal-version -1 :trans-version "20100505" :date "09-Jul-2010 16:35:21.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 104848 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12308 :visit-id "06" :obset-id "06" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12308 :visit-id "06" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2942 :al-overhead-at-end 200 :internal-dur-at-end 321 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3275 :pcs-gap 0 ) true 1 0 /home/eric/PROPOSALS/HST/CYCLE18/ZNII/PHASE2/OP-cache/GO12308phase2-v07.xml The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12308 :visit-id "07" :proposal-version -1 :trans-version "20100505" :date "09-Jul-2010 16:35:24.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 191856 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12308 :visit-id "07" :obset-id "07" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12308 :visit-id "07" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2942 :al-overhead-at-end 200 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3275 :pcs-gap 0 ) (Tic-Orbit :proposal-id 12308 :visit-id "07" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3053 :al-overhead-at-end 200 :internal-dur-at-end 321 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3275 :pcs-gap 0 ) true 2 0 /home/eric/PROPOSALS/HST/CYCLE18/ZNII/PHASE2/OP-cache/GO12308phase2-v08.xml The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12308 :visit-id "08" :proposal-version -1 :trans-version "20100505" :date "09-Jul-2010 16:35:26.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 104848 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12308 :visit-id "08" :obset-id "08" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12308 :visit-id "08" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2901 :al-overhead-at-end 200 :internal-dur-at-end 321 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) true 1 0