Changed visit 03 Between to 28-march-2010 tp 05-apr-2010, to gain access to parallax factor that had been unavailable under two-gyro mode. ----- Attempting Submission 1 (Tue Aug 05 00:43:20 GMT 2008) ----- Phase II Proposal 11786 (11786.apt) successfully submitted. ----- Attempting Submission 2 (Tue Aug 05 17:32:20 GMT 2008) ----- ----- Attempting Submission 3 (Sat Jul 04 19:17:30 GMT 2009) ----- ----- Attempting Submission 4 (Mon Jul 27 19:34:56 GMT 2009) ----- HST Observations of Astrophysically Important Visual Binaries This is a continuation of a project begun in Cycle 7 and continued up through Cycle 14. The program consists of annual FGS or WFPC2 observations of three visual binary stars that will yield fundamental astrophysical results, once their orbits and masses are determined. In Cycle 17 we are changing WFPC2 to WFC3. Our targets are the following: (1) Procyon (P = 40.9 yr), for which our first WFPC2 images yielded an extremely accurate angular separation of the bright F star and its much fainter white-dwarf companion. Combined with ground-based astrometry of the bright star, our observation significantly revised downward the derived masses, and brought Procyon A into much better agreement with theoretical evolutionary masses for the first time. With the continued monitoring proposed here, we will obtain masses to an accuracy of better than 1%, providing a testbed for theories of both Sun-like stars and white dwarfs. (2) G 107-70, a close double white dwarf (P = 18.5 yr) that promises to add two accurate masses to the tiny handful of white-dwarf masses that are directly known from dynamical measurements. (3) Mu Cas (P = 20.8 yr), a famous nearby metal-deficient G dwarf for which accurate masses will lead to the stars' helium contents, with cosmological implications. For all three stars, we will also be setting increasingly stringent limits on the presence of planetary-mass bodies in the systems.
This is the Cycle 17 continuation of a 3-cycle program in which we are determining the orbits of three visual binaries. The targets are Procyon, mu Cas, and G 107-70. We have been observing G 107-70 with FGS, and this part of the program will continue as before, with 1 orbit of POS mode observations of the target and reference stars. We had been observing Procyon and mu Cas with WFPC2. Following SM4, we are changing to WFC3/UVIS. For Procyon we will use the long-wavelength F953N filter to reduce its signal. Since even with this filter Procyon A will saturate in the minimum WFC3 exposure, we will let it saturate and use the diffraction spikes to centroid Procyon A. These exposures will be 12 sec. We will alternate these with 36-sec exposures, which will provide good unsaturated exposures for Procyon B at the same telescope pointing. For mu Cas, we will use 1-sec exposures in F225W, which the WFC3 ETC predicts will not saturate. These will be followed at each dither position with a 260-sec exposure, which will be well exposed for the cool dM companion. 12 false 0.0 0.0 false false false false false SUPPORTED STAR DA F3-F9 Coords are for center of gravity of binary. Accuracy confirmed by 2000 Nov 28 WFPC2 observations. 6/14/06: updated to ICRS system using galex website. B-V = 0.42 ALPHA-CMI HR2943 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR G V-IV Coordinate accuracy confirmed by 2000-01 WFPC2 observations. 6/14/06: updated to ICRS system using galex website. B-V = 0.70 HR321 HD6582 J2000 00 00 0.0000 +00 00 0.00 J2000 STAR DC double degenerate binary system, separation ~0.6" J2000 00 00 0.0000 +00 00 0.00 J2000 STAR M V-IV CPM companion to G107-70, ~1 arcmin distant J2000 00 00 0.0000 +00 00 0.00 J2000 CALIBRATION ASTROMETRIC J2000 00 00 0.0000 +00 00 0.00 J2000 CALIBRATION ASTROMETRIC J2000 00 00 0.0000 +00 00 0.00 J2000 CALIBRATION ASTROMETRIC J2000 00 00 0.0000 +00 00 0.00 J2000 CALIBRATION ASTROMETRIC J2000 00 00 0.0000 +00 00 0.00 J2000 CALIBRATION ASTROMETRIC J2000 00 00 0.0000 +00 00 0.00 J2000 CALIBRATION ASTROMETRIC J2000 00 00 0.0000 +00 00 0.00 J2000 POS-TARG DITHER 0.173 LINE 0.112 false true 81.785 4 23.884 WFC3-UVIS-DITHER-BOX 1 false The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. ORIENT requirement is done so that companion star will not lie near diffraction spikes or charge bleeding from the very bright primary star. (Tic-Visit :proposal-id 11786 :visit-id "01" :proposal-version -1 :trans-version "20090130" :date "03-Jul-2009 20:04:04.0" :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 139792 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11786 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11786 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2574 :al-overhead-at-end 44 :internal-dur-at-end 191 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3242 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. ORIENT requirement is done so that companion star will not lie near diffraction spikes or charge bleeding of primary star. (Tic-Visit :proposal-id 11786 :visit-id "02" :proposal-version -1 :trans-version "20090130" :date "04-Jul-2009 14:27:45.0" :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 69904 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11786 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11786 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2936 :al-overhead-at-end 42 :internal-dur-at-end 115 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3300 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 17.2. CASM was run in Phase II mode. /private/tmp/OPVisit4228571921816477586.xml Maximum parallax factors April 10, October 11. This ORIENT can schedule up to April 6, and results in a favorable projection of the G107-70 components (PA ~ 189 degrees) in the FGS frame. (Tic-Visit :proposal-id 11786 :visit-id "03" :proposal-version -1 :trans-version "20090130" :date "27-Jul-2009 15:31:47.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "05" :si-bright-earth-limb-angle 15.5 :data-volume 0 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 11786 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 11786 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2995 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3398 :pcs-gap 0 ) true 1 0