0 Assigned ID: 594 ----- Attempting Submission 1 (Fri Apr 08 17:04:59 GMT 2016) ----- HST Phase I Proposal 594 (BetaPic_OH_apt.apt) successfully submitted. Receipt: # 594-1 ----- Attempting Submission 2 (Fri Apr 08 23:38:34 GMT 2016) ----- HST Phase I Proposal 594 (BetaPic_OH_apt.apt) successfully submitted. Receipt: # 594-2 ----- Attempting Submission 3 (Fri Apr 08 23:44:11 GMT 2016) ----- HST Phase I Proposal 594 (BetaPic_OH_apt.apt) successfully submitted. Receipt: # 594-3 ----- Attempting Submission 4 (Sat Apr 09 00:10:55 GMT 2016) ----- HST Phase I Proposal 594 (BetaPic_OH_apt.apt) successfully submitted. Receipt: # 594-4 ----- Attempting Submission 5 (Sat Apr 09 00:14:54 GMT 2016) ----- 0 0 ----- Attempting Submission 1 (Wed Jul 20 23:36:24 GMT 2016) ----- Observation of OH in Beta Pictoris exocomets The Beta Pictoris system is a young planetary system embedded in a debris disk that is continually replenished by the collision and evaporation of planetesimals and exocomets. As a result of the edge-on inclination of the debris disk, transiting exocomets can be observed in great detail using absorption spectroscopy. Our previous COS observations yielded the first detection of exocomets in the far-UV, with the discovery of several new exocometary species including HI, CII, NI, OI and several ionization states of Si. Interestingly, the C/O ratio in the exocomets seems to also distinguish the two dynamically different exocomet populations known to exist in the Beta Pictoris system. Here we propose to search for OH variable absorptions at 3085 Ang. to measure the abundance of water and to identify if water is the key volatile in the exocomets of Beta Pictoris. Positive detections of OH in the exocomets would be the first indirect discovery of water in the Beta Pictoris disk. Moreover, we will investigate the possibility that the two dynamically different exocomet populations have different compositions and origins. These objectives can be achieved by the acquisition of STIS Echelle spectra at different epochs. Measuring the abundance of OH and the OH/Mg ratio in the Beta Pic evaporating exocomets will enable us to trace the condensation and evaporation processes and their location in the late stages of planetary formation. This will provide valuable insights into the origins of the exocomets of the Beta Pictoris system. Observation strategy ===================== We wish to observe Beta Pictoris once at 3 different epochs separated by at least 2 weeks. The objective of this program is to put forward transient absorptions in the UV due to transit of exo-cometary clouds in front of Beta Pic. For this purpose it is essential that the system is observed at different well separated epochs. In order to unravel flux dimming due to exocomet transit, we need to compare spectral regions when they present absorption signatures to when they only present the quiet stellar continuum. Our observations of the numerous exo-cometary transits in the Ca II doublet lines of Beta Pic have shown that the rate of exocometary transit fluctuates aperiodically by as much as a factor of 2 during a year. Therefore, the largest possible time separation between our 3 different visits (15 to 90 days) would maximize our chance to get spectra at both low and high exocometary transit rates. It would guaranty the best scientific return for this program, allowing for an unbiased estimation of the abundance of the absorbing elements evaporated from the transiting comets. Since Beta Pic is very bright (V~3.86), we choose to use the 31x0.05NDA slit that guaranties a limited illumination of the STIS-MAMA. It was selected over the 0.1x0.03 aperture, based on simpler target acquisition overheads, while with similar optical properties. We will divide the unique orbit of each 3 visits into 2 exposures, and make use for both exposures of the E230H-STIS grating. -- The first ~475s exposure will be dedicated to observe the Mg II line at 2800 Ang. with the E230H/2812 order, aiming at S/N~40. -- The second ~1204s exposure will be dedicated to observe the OH line at 3085 Ang. with the E230H/2962 order. aiming at S/N>65. Our main objective is the observation of OH line at 3085 Ang., which was never observed for transiting exocomets, and could be as shallow as a few percent. So it is essential for us to maximize the S/N for the second exposure. The exocomet transit signatures in the Mg II line (2800 Ang.) on the other hand are usually deep and a minimum S/N (~40) will be enough for detection, and accurate abundance measurements. Extrasolar Planets and Planet Formation 6 false true false false false false AVAILABLE STAR A4-A9 V-IV CIRCUMSTELLAR MATTER DISK LOW MASS COMPANION NO This object was generated by the target selector and retrieved from the SIMBAD database. HD39060 HR2020 J2000 J2000 STIS/NUV-MAMA Spectroscopic No No E230H 2812 STIS/NUV-MAMA Spectroscopic No No E230H 2962 Timing link suitability includes constraints ([02 After 01 by 15.0 to 90.0 days]) The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. First observation of Beta Pic. 1 orbit separated in 2 exposures with E230H grating at -- 2812 Ang. (475s) -- 2962 Ang. (1204s) 1507590859000 288.5677111021582 (Tic-Visit :proposal-id 14735 :visit-id "01" :proposal-version -1 :trans-version "20160601" :date "19-Jul-2016 11:28:57.0" :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 174976 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14735 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14735 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3069 :al-overhead-at-end 132 :internal-dur-at-end 394 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3403 :pcs-gap 0 ) false 1 0 Timing link suitability includes constraints ([02 After 01 by 15.0 to 90.0 days] [03 After 02 by 15.0 to 90.0 days]) The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. Second observation of Beta Pic. Should be done at least 15 days after the first visit. 1 orbit separated in 2 exposures with E230H grating at -- 2812 Ang. (475s) -- 2962 Ang. (1204s) 1512276886000 343.2975060730539 (Tic-Visit :proposal-id 14735 :visit-id "02" :proposal-version -1 :trans-version "20160601" :date "19-Jul-2016 11:58:12.0" :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 174976 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14735 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14735 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3069 :al-overhead-at-end 132 :internal-dur-at-end 394 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3403 :pcs-gap 0 ) true 1 0 Timing link suitability includes constraints ([03 After 02 by 15.0 to 90.0 days]) The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. Third and last observation of Beta Pic. Should be done at least 15 days after the second visit. 1 orbit separated in 2 exposures with E230H grating at -- 2812 Ang. (475s) -- 2962 Ang. (1204s) 1515568204000 25.0 (Tic-Visit :proposal-id 14735 :visit-id "03" :proposal-version -1 :trans-version "20160601" :date "19-Jul-2016 11:58:16.0" :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 174976 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14735 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14735 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3069 :al-overhead-at-end 132 :internal-dur-at-end 394 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3403 :pcs-gap 0 ) true 1 0 Second observation of Beta Pic. Should be done at least 15 days after the first visit. 1 orbit separated in 2 exposures with E230H grating at -- 2812 Ang. (475s) -- 2962 Ang. (1204s) 1516924411000 39.54819928804011 (Tic-Visit :proposal-id 14735 :visit-id "02" :proposal-version -1 :trans-version "20160601" :date "19-Jul-2016 11:58:12.0" :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 174976 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14735 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14735 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3069 :al-overhead-at-end 132 :internal-dur-at-end 394 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3403 :pcs-gap 0 ) false 1 0 Second observation of Beta Pic. Should be done at least 15 days after the first visit. 1 orbit separated in 2 exposures with E230H grating at -- 2812 Ang. (475s) -- 2962 Ang. (1204s) (Tic-Visit :proposal-id 14735 :visit-id "02" :proposal-version -1 :trans-version "20160601" :date "19-Jul-2016 11:58:12.0" :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 174976 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14735 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14735 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3069 :al-overhead-at-end 132 :internal-dur-at-end 394 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3403 :pcs-gap 0 ) false 1 0