Proprietary Period changed to 3 months. -1345858797 Assigned ID: 676 ----- Attempting Submission 1 (Wed Jan 30 22:50:54 GMT 2019) ----- HST Phase I Proposal 676 (mc_26_3.apt) successfully submitted. Receipt: # 676-1 ----- Attempting Submission 2 (Thu Jan 31 01:32:06 GMT 2019) ----- FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser FLASH level may be too high for this exposure or a long subexposure. See extended explanation in the diagnostic browser Visits 4 is ready for scheduling. 1096908340 ----- Attempting Submission 1 (Mon Mar 25 21:23:19 GMT 2019) ----- ----- Attempting Submission 2 (Tue Mar 26 15:04:09 GMT 2019) ----- ----- Attempting Submission 3 (Wed Mar 27 18:39:53 GMT 2019) ----- ----- Attempting Submission 4 (Tue May 21 09:06:51 GMT 2019) ----- ----- Attempting Submission 5 (Wed May 22 14:22:20 GMT 2019) ----- ----- Attempting Submission 6 (Thu Jul 25 15:07:44 GMT 2019) ----- ----- Attempting Submission 7 (Mon Nov 18 17:06:49 GMT 2019) ----- ----- Attempting Submission 8 (Wed Mar 18 20:13:37 GMT 2020) ----- Visit 4 is ready. Exposures are identical to visit 4 exposures. Accurate Mass Determination of the Nearby Single White Dwarf L145-141 (LAWD 37) through Astrometric Microlensing White dwarf (WD) is the final stage for a vast majority of stars, and WDs are important in a variety of astrophysical and galactic contexts. However, there are surprisingly few WDs with direct mass measurements, all of them in binaries. It has been reported recently that the fifth-nearest WD, L145-141 (LAWD 37), will pass closely in front of a background star in late 2019, with an impact parameter of only 380 milliarcsec. As it passes in front, the WD will relativistically deflect the light from the background star, providing a unique opportunity for direct measurement of the WD's mass. The gravitational deflection angle depends only on the distances and relative positions of the stars, and on the mass of the WD. Since the distances and positions can be determined precisely before the event, the astrometric measurement offers a direct method to measure the mass of the WD to high accuracy (~2.5%). Precision HST astrometry was recently used to measure the astrometric deflection caused by the nearby white dwarf Stein 2051B, and thus measure its mass--the first application of this technique outside the solar system. We now propose to repeat this experiment for a second WD. Relativistic astrometric microlensing is the only available model-independent technique for determining the mass of a single WD. Our target is of special interest because it is the second-nearest single WD (after van Maanen's Star). Our measurement will be the first model-independent mass measurement of a single WD, and will add to the surprisingly small number of accurate model-independent mass determinations for WDs--a key element in testing the theoretical mass-radius relation. We have tweaked the observing strategy that was used in program GO-14448 to determine the mass of Stein 2051B, in order to improve the accuracy even further. At each epoch, we will obtain images in WFC3/UVIS F814W (I-band). The contrast between source and lens is best in this filter, and its PSF is well characterized. We will use a 2kx2k subarray to ensure that there are enough reference stars within the field, yet interruptions for buffer dumps will be unnecessary. At one epoch we will also obtain a few frames in F555W (V -band) in order to estimate the spectral types of the source and reference stars, and thus refine their distance estimates. Since the astrometric deflection measurements are differential, it is important to measure them at several epochs, including close to the baseline and the peak. In addition, there must be enough epochs to independently solve for the proper motions and parallaxes of the reference stars and source. These considerations dictate our proposal to observe at 8 epochs beginning in April 2019. Stellar Physics 3 false false false false false false false AVAILABLE STAR K III-I NO J2000 J2000 EXT-STAR DC NO J2000 WFC3/UVIS Imaging No No F814W WFC3/UVIS Imaging No No F555W The scheduling data was generated by CASM 27.2. CASM was run in Phase II mode. 51.6 /solaris/user1/dctaylor/proposals2/OP-cache/15961-v01.xml ORIENT constraints are used to avoid diffraction spikes and bleed columns from the bright lens star falling near the faint source star. 1573422071000 238.49693653677923 (Tic-Visit :proposal-id 15961 :visit-id "01" :proposal-version -1 :trans-version "20190514" :date "25-Jul-2019 11:38:43.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 703872 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15961 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15961 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2828 :al-overhead-at-end 173 :internal-dur-at-end 190 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3411 :pcs-gap 0 ) false 1 0 The scheduling data was generated by CASM 27.2. CASM was run in Phase II mode. 51.64 ORIENT constraints are used to avoid diffraction spikes and bleed columns from the bright lens star falling near the faint source star. 1575577359000 270.0 (Tic-Visit :proposal-id 15961 :visit-id "02" :proposal-version -1 :trans-version "20190514" :date "18-Nov-2019 11:55:47.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 320848 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15961 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15961 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2811 :al-overhead-at-end 85 :internal-dur-at-end 387 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3411 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 27.2. CASM was run in Phase II mode. 51.64 ORIENT constraints are used to avoid diffraction spikes and bleed columns from the bright lens star falling near the faint source star. 1578015364000 297.0 (Tic-Visit :proposal-id 15961 :visit-id "03" :proposal-version -1 :trans-version "20190514" :date "18-Nov-2019 12:02:47.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 320848 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15961 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15961 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2811 :al-overhead-at-end 85 :internal-dur-at-end 387 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3411 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 28.0. CASM was run in Phase II mode. 51.64 /private/var/folders/56/c_jk44c970v8fj73rtx427cm0006v6/T/OPVisit15734219236653374926.xml ORIENT constraints are used to avoid diffraction spikes and bleed columns from the bright lens star falling near the faint source star. (Tic-Visit :proposal-id 15961 :visit-id "04" :proposal-version -1 :trans-version "20191203" :date "18-Mar-2020 17:02:52.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 320848 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15961 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15961 :visit-id "04" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2811 :al-overhead-at-end 85 :internal-dur-at-end 387 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3411 :pcs-gap 0 ) true 1 0