0 Assigned ID: 695 ----- Attempting Submission 1 (Fri Apr 07 17:58:09 GMT 2017) ----- ORBITAL VISIBILITY OVERRUN ORBITAL VISIBILITY OVERRUN ORBITAL VISIBILITY OVERRUN ORBITAL VISIBILITY OVERRUN ORBITAL VISIBILITY OVERRUN Visit 1 failed because STAR-A is within the acquisiton field and is brighter than the target. Aquisition has been revised to start with STAR-A-OFFSET which is about 2 arcsec from the target. The peak up is then done on the target coordinates. Exposures had to be shortened to fit in the new orbit windows. 2114758684 ----- Attempting Submission 1 (Thu Jul 20 08:35:31 GMT 2017) ----- HST Phase II Proposal 15273 (nher_phase2.apt) successfully submitted. Receipt: # 15273-1 ----- Attempting Submission 2 (Thu Jul 20 17:29:45 GMT 2017) ----- ----- Attempting Submission 3 (Wed Jul 10 20:43:56 GMT 2019) ----- Warnings are for Visit 1 which has completed. V838 Her was one of the fastest fading novae ever observed. Its nebular spectrum revealed unusual abundance ratios including a high sulfur content. These observations strongly imply that the white dwarf in the system is very close to the Chandrasekhar limit and may be the most massive known. However, no direct radial velocity measurements have confirmed this assertion. Our attempt to directly measure the mass was foiled by the light of very nearby stars contaminating the nova spectra and suppressing the estimated orbital velocity of the donor star. We propose STIS high-angular resolution spectroscopy to eliminate any contamination and make a definitive, trustworthy mass measurement for the V838~Her white dwarf. We propose time-resolved spectroscopy of V838 Her with the STIS covering one binary orbit. Because the orbit is 7.1 hours long and the target visibility is 54 minutes, we will break the observations up into two visits. The first visit will be 5 HST orbits and cover an entire binary orbit. The second visit will be timed to fill in holes in phase created by the Earth occultations in the first visit. By coincidence, actually observing 9 consecutive orbits would naturally fill in the gaps, but such long periods of continuous observing are not commonly available. We have calculated that starting the second visit 63 HST orbits (4.2 days) after the beginning of the first visit will also fill all the missing phases. Longer delays (121, 130, 188 ... HST orbits) before starting the second visit will also work. V838 Her has a brightness of R=19.0 mag. This is too faint for the medium resolution gratings, but good signal-to-noise ratio (SNR) can be achieved with the low resolution grat- ing. Because the velocity amplitude is expected to be large, we will still achieve sufficient velocity resolution to measure the WD mass. We plan to use the 0.1 arcsec wide slit to improve the resolution while not significantly impacting the throughput. The narrow slit is critical for absorption line measurements because it maximizes spectral purity. To avoid the emission lines from the disk that dominate the blue wavelengths, we will use the G750L grating and cover 530-1000 nm. This will include the strong NaI line as well as hundreds of weaker absorption lines found in K-type stars. These weak lines are important for the cross-correlation velocity measurement method. To reduce fringing beyond 700 nm we will take contemporaneous fringe flats that add 2 minutes of overhead. With the G750L grating and 0.1-arcsec slit we will achieve a velocity resolution of 400 km/s. Using the cross-correlation technique, the velocity uncertainty per spectrum will be 35 km/s or an unbiased velocity amplitude good to 5% . The STIS ETC shows that we will reach a S/N= 13 per resolution element in a 900 sec exposure on the 19.0 mag star. Because of the multiplexing from cross-correlation this will be sufficient S/N to make an accurate velocity measurement. Stellar Physics 6 false false false false false false false SUPPORTED STAR CLASSICAL NOVA INTERACTING BINARY K V-IV NO The position was determined from the GSC2 catalog. A plate solution was determined on a VATT image taken in 2016 and applied to the nova. J2000 J2000 EXT-STAR K V-IV NO STAR-A J2000 STIS/CCD Spectroscopic No No G750L 7751 1562791365801 The scheduling data was generated by CASM 27.2. CASM was run in Phase II mode. /private/var/folders/j1/730l_tzs09jdnw98498x_l080000gr/T/OPVisit6939733318078585805.xml 1538373950000 85.59445 (Tic-Visit :proposal-id 15273 :visit-id "01" :proposal-version -1 :trans-version "20190514" :date "10-Jul-2019 16:42:44.0" :trans-errors '(:WARNINGS 5 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 5 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 626160 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15273 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15273 :visit-id "01" :orbit-number 1 :pcs-time 393 :si-vis-utilization 2876 :al-overhead-at-end 0 :internal-dur-at-end 276 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3149 :pcs-gap 0 ) (Tic-Orbit :proposal-id 15273 :visit-id "01" :orbit-number 2 :pcs-time 302 :si-vis-utilization 2984 :al-overhead-at-end 0 :internal-dur-at-end 276 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3149 :pcs-gap 0 ) (Tic-Orbit :proposal-id 15273 :visit-id "01" :orbit-number 3 :pcs-time 302 :si-vis-utilization 2986 :al-overhead-at-end 72 :internal-dur-at-end 276 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3149 :pcs-gap 0 ) (Tic-Orbit :proposal-id 15273 :visit-id "01" :orbit-number 4 :pcs-time 302 :si-vis-utilization 2984 :al-overhead-at-end 0 :internal-dur-at-end 276 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3149 :pcs-gap 0 ) (Tic-Orbit :proposal-id 15273 :visit-id "01" :orbit-number 5 :pcs-time 302 :si-vis-utilization 2984 :al-overhead-at-end 0 :internal-dur-at-end 715 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3149 :pcs-gap 0 ) true 5 5 Initial exposure for V=20 mag target, spectrum = K4V Exposure through 0.1 arcsec slit for V=20 mag target, spectrum = K4V 1562790648249 The scheduling data was generated by CASM 27.2. CASM was run in Phase II mode. /private/var/folders/j1/730l_tzs09jdnw98498x_l080000gr/T/OPVisit14766790461664183913.xml Have removed "after" restriction since Visit 01 completed (Tic-Visit :proposal-id 15273 :visit-id "02" :proposal-version -1 :trans-version "20190514" :date "10-Jul-2019 16:30:48.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 4 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 497344 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15273 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15273 :visit-id "02" :orbit-number 1 :pcs-time 393 :si-vis-utilization 2756 :al-overhead-at-end 0 :internal-dur-at-end 276 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3149 :pcs-gap 0 ) (Tic-Orbit :proposal-id 15273 :visit-id "02" :orbit-number 2 :pcs-time 302 :si-vis-utilization 2847 :al-overhead-at-end 0 :internal-dur-at-end 276 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3149 :pcs-gap 0 ) (Tic-Orbit :proposal-id 15273 :visit-id "02" :orbit-number 3 :pcs-time 302 :si-vis-utilization 2847 :al-overhead-at-end 0 :internal-dur-at-end 276 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3149 :pcs-gap 0 ) (Tic-Orbit :proposal-id 15273 :visit-id "02" :orbit-number 4 :pcs-time 302 :si-vis-utilization 2847 :al-overhead-at-end 72 :internal-dur-at-end 675 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3149 :pcs-gap 0 ) true 4 0 Initial exposure for V=20 mag target, spectrum = K4V Exposure through 0.1 arcsec slit for V=20 mag target, spectrum = K4V