Spanning the Reionization History of IGM Helium: a Highly Efficient Spectral Survey of the Far-UV-Brightest Quasars

Spanning the Reionization History of IGM Helium: a Highly Efficient Spectral Survey of the Far-UV-Brightest Quasars The reionization of IGM helium likely occurred at redshifts of z=3 to 4. Detailed studies of HeII Ly-alpha absorption toward a handful of quasars at 2.7<z<3.3 confirm the potential of such IGM probes, but the small sample and redshift range limited confidence in cosmological inferences. The requisite unobscured sightlines to high redshift are extremely rare; but we've cross-correlated 10,000 z>2.8 SDSS DR7 (and other) quasars with GALEX GR4/5, to identify 630 candidates potentially useful for HST HeII studies. Our cycle 15-16 HST trials confirm our approach, verifying twenty new HeII quasars at unprecedented 40% efficiency. We propose to complete the first efficient (80% with refinements) survey for HeII quasars, via reconnaissance (~1 orbit) COS spectra of a highly select subset of 17 SDSS/GALEX quasars at 2.7<z<3.8. Along with past work, this program will yield 3-4 of the brightest far-UV HeII sightlines within each of 10-12 redshift bins spanning 2.7<z<3.8, enabling a community sample suitable for detailed spectral follow-up with HST. Herein, we will also directly obtain quality UV spectral stacks within each redshift bin to trace the reionization history of IGM helium; such spectral stacks average over cosmic variance and individual object pathology. Our high-yield HeII sightline sample and spectral stacks will enable confident conclusions about the IGM baryon density, the spectrum and evolution of the ionizing background, the evolution of HeII opacity, and the epoch of helium reionization.

We will obtain COS G140L FUV spectra of 17 z>2.8 quasars, filling 20 orbits in a high-efficiency search for new He II Gunn-Peterson trough sightlines. Our targets come from cross-matching known quasars with the GALEX UV catalogs, and our prior experience indicates ~80% of our targets will be clean He II sightlines. Target acquisition times and bright object safety concerns are directly addressed with the GALEX fluxes. Most targets will take one-orbit observations, with three targets using two orbits. All our targets, even those that lack SDSS spectra, have very precise positions from SDSS imaging. Following COS ISR 2010-14, we therefore do not use ACQ/SEARCH for any targets, and use only ACQ/IMAGE for all targets. (We use S/N=40 in all cases except one quasar that is NUV-faint, in which case we use S/N=35. This quasar does not need a second orbit because it is FUV-bright.) In nearly all cases we use the 1105 center wavelength of G140L, to maximize coverage of each quasar's emission, proximity zone, and Gunn-Peterson trough. In one case we use the 1280 wave center for one orbit, to access the Lyman-beta trough of this uniquely bright and high-redshift object (we are limited at short wavelength only by instrument sensitivity). In this case we use FP-POS 1 and 4 to minimize the gap between segments. For all 1105 observations we use at least FP-POS 3 and 4; we will be obtaining moderate S/N spectra, and so two FP-POS values will be sufficient. We use the defaults for SEGMENT and FLASH on all observations. QUASAR ABSORPTION LINES AND IGM 12 false 0.0 0.0 false false false false SUPPORTED GALAXY HIGH REDSHIFT GALAXY QSO J2000 00 54 1.4815 +00 28 47.79 J2000 GALEX: NUV=4.4e-17, FUV=6.2e-17; SDSS: u=24.21, g=20.53, r=19.91, i=19.89, z=19.76 GALAXY HIGH REDSHIFT GALAXY QSO J2000 08 55 3.8112 +29 32 48.94 J2000 GALEX: NUV=6.2e-17, FUV=8.5e-17; SDSS: u=22.50, g=19.53, r=19.09, i=18.99, z=18.89 GALAXY HIGH REDSHIFT GALAXY QSO J2000 00 00 0.0000 +00 00 0.00 J2000 GALEX: NUV=10.17e-17, FUV=8.83e-17; SDSS: u=20.63, g=18.98, r=18.69, i=18.60, z=18.53 GALAXY HIGH REDSHIFT GALAXY QSO J2000 09 15 10.0104 +47 56 58.83 J2000 GALEX: NUV=16.1e-17, FUV=28.4e-17; SDSS: u=19.56, g=18.16, r=17.85, i=17.81, z=17.73 GALAXY HIGH REDSHIFT GALAXY QSO J2000 09 47 34.2024 +14 21 16.99 J2000 GALEX: NUV=28.1e-17, FUV=24.7e-17; SDSS: u=18.69, g=17.42, r=17.23, i=17.02, z=16.92 GALAXY HIGH REDSHIFT GALAXY QSO J2000 09 55 46.3560 +43 22 44.80 J2000 GALEX: NUV=3.8e-17, FUV=16.5e-17; SDSS: u=21.29, g=19.69, r=19.48, i=19.43, z=19.42 GALAXY HIGH REDSHIFT GALAXY QSO J2000 10 25 9.6456 +04 52 46.70 J2000 GALEX: NUV=4.4e-17, FUV=14.1e-17; SDSS: u=21.75, g=18.27, r=18.01, i=17.91, z=17.83 GALAXY HIGH REDSHIFT GALAXY QSO J2000 10 27 34.1328 +18 34 27.59 J2000 GALEX: NUV=23.8e-17, FUV=47.4e-17; SDSS: u=18.90, g=18.00, r=17.83, i=17.70, z=17.70 GALAXY HIGH REDSHIFT GALAXY QSO J2000 12 18 15.5928 +11 45 51.89 J2000 GALEX: NUV=22.9e-17, FUV=24.9e-17; SDSS: u=18.69, g=18.01, r=17.91, i=17.88, z=17.91 GALAXY HIGH REDSHIFT GALAXY QSO J2000 00 00 0.0000 +00 00 0.00 J2000 GALEX: NUV=19.5e-17, FUV=22.0e-17; SDSS: u=19.18, g=18.26, r=18.14, i=18.05, z=17.98 GALAXY HIGH REDSHIFT GALAXY QSO J2000 00 00 0.0000 +00 00 0.00 J2000 GALEX: NUV=5.95e-17, FUV=17.0e-17; SDSS: u=20.20, g=18.77, r=18.63, i=18.68, z=18.63 GALAXY HIGH REDSHIFT GALAXY QSO J2000 14 43 11.5896 +35 46 46.37 J2000 GALEX: NUV=8.9e-17, FUV=19.0e-17; SDSS: u=19.88, g=18.84, r=18.79, i=18.74, z=18.75 GALAXY HIGH REDSHIFT GALAXY QSO J2000 15 08 28.7808 +16 54 33.13 J2000 GALEX: NUV=2.1e-17, FUV=15.5e-17; SDSS: u=21.20, g=18.70, r=18.36, i=18.18, z=18.18 GALAXY HIGH REDSHIFT GALAXY QSO J2000 16 03 55.7952 +57 30 54.00 J2000 GALEX: NUV=55.5e-17, FUV=48.4e-17; SDSS: u=18.24, g=17.42, r=17.34, i=17.26, z=17.15 GALAXY HIGH REDSHIFT GALAXY QSO J2000 16 04 41.4744 +16 45 38.34 J2000 GALEX: NUV=30.4e-17, FUV=18.2e-17; SDSS: u=18.16, g=16.90, r=16.69, i=16.50, z=16.43 GALAXY HIGH REDSHIFT GALAXY QSO J2000 22 57 59.6712 +00 16 45.71 J2000 GALEX: NUV=1.1e-17, FUV=2.9e-17; SDSS: u=24.85, g=20.02, r=18.80, i=18.77, z=18.88 GALAXY HIGH REDSHIFT GALAXY QSO J2000 23 45 22.1952 +15 12 17.34 J2000 GALEX: NUV=1.4e-17, FUV=1.8e-17; SDSS: u=22.80, g=20.04, r=19.26, i=19.14, z=19.22 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 COS/FUV Spectroscopic No No G140L 1105 The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. 1288795472000 59.52579906203849 (Tic-Visit :proposal-id 12178 :visit-id "01" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:55:04.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 191440 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2890 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) true 1 0 Multiple NUV observations available; the faintest was used for target acquisition times, the brightest for bright object protection. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. 1290985568000 264.0 (Tic-Visit :proposal-id 12178 :visit-id "02" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:55:11.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 191440 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2914 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3257 :pcs-gap 0 ) true 1 0 Only one epoch of UV observations available; 0.5x flux was used for target acquisition time, 2.5x flux was used for bright object protection. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. 1286500744000 283.7187909437778 (Tic-Visit :proposal-id 12178 :visit-id "03" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:55:21.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 182752 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2892 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3245 :pcs-gap 0 ) true 1 0 Multiple NUV observations available; the faintest was used for target acquisition times, the brightest for bright object protection. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. 1286401703000 302.0700302392635 (Tic-Visit :proposal-id 12178 :visit-id "04" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:55:33.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 356736 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "04" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3048 :al-overhead-at-end 0 :internal-dur-at-end 426 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3391 :pcs-gap 0 ) (Tic-Orbit :proposal-id 12178 :visit-id "04" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3169 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3391 :pcs-gap 0 ) true 2 0 Multiple NUV observations available; the faintest was used for target acquisition times, the brightest for bright object protection. Exposure time can be adjusted as needed to fill orbit. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. 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CASM was run in Phase II mode. 1286424751000 309.3936395988424 (Tic-Visit :proposal-id 12178 :visit-id "06" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:55:56.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 191440 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "06" :obset-id "06" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "06" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2998 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3341 :pcs-gap 0 ) true 1 0 Multiple NUV observations available; the faintest was used for target acquisition times, the brightest for bright object protection. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. 1301243168000 82.25336814232918 (Tic-Visit :proposal-id 12178 :visit-id "07" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:56:05.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 191440 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "07" :obset-id "07" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "07" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2890 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) true 1 0 Multiple NUV observations available; the faintest was used for target acquisition times, the brightest for bright object protection. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. 1300090777000 144.94479334843072 (Tic-Visit :proposal-id 12178 :visit-id "08" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:56:14.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 182752 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "08" :obset-id "08" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "08" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2896 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3249 :pcs-gap 0 ) true 1 0 Only one epoch of UV observations available; 0.5x flux was used for target acquisition time, 2.5x flux was used for bright object protection. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. 1295479545000 288.2246938667458 (Tic-Visit :proposal-id 12178 :visit-id "09" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:56:23.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 182752 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "09" :obset-id "09" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "09" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2892 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3245 :pcs-gap 0 ) true 1 0 Only one epoch of UV observations available; 0.5x flux was used for target acquisition time, 2.5x flux was used for bright object protection. 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CASM was run in Phase II mode. (Tic-Visit :proposal-id 12178 :visit-id "10" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:56:32.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 182752 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "10" :obset-id "10" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "10" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2896 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3249 :pcs-gap 0 ) true 1 0 Only one epoch of UV observations available; 0.5x flux was used for target acquisition time, 2.5x flux was used for bright object protection. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12178 :visit-id "11" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:56:41.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 191440 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "11" :obset-id "11" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "11" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3172 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3516 :pcs-gap 0 ) true 1 0 Only one epoch of UV observations available; 0.5x flux was used for target acquisition time, 2.5x flux was used for bright object protection. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12178 :visit-id "12" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:56:51.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 191440 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "12" :obset-id "12" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "12" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2958 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3301 :pcs-gap 0 ) true 1 0 Multiple NUV observations available; the faintest was used for target acquisition times, the brightest for bright object protection. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12178 :visit-id "13" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:57:00.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 200128 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "13" :obset-id "13" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "13" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2905 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3249 :pcs-gap 0 ) true 1 0 Only one epoch of UV observations available; 0.5x flux was used for target acquisition time, 2.5x flux was used for bright object protection. Acquisition time estimate is for S/N=35 since this object is NUV-faint, although relatively FUV-bright. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. 1299214363000 245.0 (Tic-Visit :proposal-id 12178 :visit-id "14" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:57:09.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 182752 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "14" :obset-id "14" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "14" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3168 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3511 :pcs-gap 0 ) true 1 0 Multiple NUV observations available; the faintest was used for target acquisition times, the brightest for bright object protection. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. (Tic-Visit :proposal-id 12178 :visit-id "15" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:57:19.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 182752 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "15" :obset-id "15" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "15" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2896 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3249 :pcs-gap 0 ) true 1 0 Only one epoch of UV observations available; 0.5x flux was used for target acquisition time, 2.5x flux was used for bright object protection. Exposure time can be adjusted as need to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. 1287223566000 75.60712923811889 (Tic-Visit :proposal-id 12178 :visit-id "16" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:57:28.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 261024 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "16" :obset-id "16" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "16" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2891 :al-overhead-at-end 0 :internal-dur-at-end 116 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) (Tic-Orbit :proposal-id 12178 :visit-id "16" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3003 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3234 :pcs-gap 0 ) true 2 0 Multiple NUV observations available; the faintest was used for target acquisition times, the brightest for bright object protection. Exposure time can be adjusted as needed to fill orbit. Exposure time can be adjusted as needed to fill orbit. The scheduling data was generated by CASM 18.3.1. CASM was run in Phase II mode. 1286965017000 108.55180837617633 (Tic-Visit :proposal-id 12178 :visit-id "17" :proposal-version -1 :trans-version "20100505" :date "06-Jul-2010 14:57:39.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "31" :si-bright-earth-limb-angle 20.0 :data-volume 261024 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 12178 :visit-id "17" :obset-id "17" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 12178 :visit-id "17" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2906 :al-overhead-at-end 0 :internal-dur-at-end 116 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3249 :pcs-gap 0 ) (Tic-Orbit :proposal-id 12178 :visit-id "17" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3023 :al-overhead-at-end 0 :internal-dur-at-end 428 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3249 :pcs-gap 0 ) true 2 0 Multiple NUV observations available; the faintest was used for target acquisition times, the brightest for bright object protection. Exposure time can be adjusted as needed to fill orbit. Exposure time can be adjusted as needed to fill orbit.