! Proposal 6750, submission 1 ! PI: Ronald Polidan ! Received Wed Feb 21 18:02:15 EST 1996 ! From: aberman@stsci.edu ! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template ! ! Refer to the HST Phase II Proposal Instructions to fill this out ! ! Anything after a "!" is ignored, and may be deleted ! ! All keywords with multiple entries are comma delimited except the ! Visit_Requirements and Special_Requirements keywords which can be ! delimited with carriage returns or semi-colons, but not commas ! ! For help call your Program Coordinator: Alice Berman ! Phone: 410-338-4462 , E-mail: aberman@stsci.edu ! ! This partially completed template was generated from a Phase I proposal. Proposal_Information ! Section 4 Title: Spectropolarimetry of Ultraviolet Continuum and Line Emissions in Binary Stars Proposal_Category: GO Scientific_Category: BINARIES AND STAR FORMATION Cycle: 6 Investigators PI_name: Ronald Polidan PI_Institution: NASA/Goddard Space Flight Center CoI_Name: Charles Keyes CoI_Institution: Space Telescope Science Institute Contact: ! Y or N (designate at most one contact) CoI_Name: David Lynch CoI_Institution: Global Science and Technology Contact: ! Y or N (designate at most one contact) CoI_Name: Kenneth Nordsieck CoI_Institution: University of Wisconsin Contact: ! Y or N (designate at most one contact) CoI_Name: Geraldine Peters CoI_Institution: University of Southern California Contact: ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) We propose to obtain FOS spectropolarimetric observations of two interacting binary systems, V356 Sgr and TT Hya, in primary eclipse and outside of eclipse to establish the degree to which the UV emission lines and the excess continuum flux seen in these binary systems is polarized. In addition, the FOS ultraviolet spectra will be analyzed, independent of their polarization information, since they will represent the highest S/N spectra ever obtained of these two stars in eclipse (for TT Hya they will also be the highest resolution UV spectra obtained in eclipse). Earlier (1993) outside of eclipse FOS spectropolarimetry of V356 Sgr clearly shows intrinsic polarization, suggestive of a bipolar flow. No previous UV spectropolarimetric observations of TT Hya exist. Analysis of the UV spectrum and its polarization properties will yield information on the location of the continuum and emission line formation region(s), the role of electron scattering in the observed broad line widths, and insight into the origin, geometry, and physical characteristics of the circumstellar matter. Thus, the origin of the excess UV continuum and the strong high ionization emission lines, and possibly bipolar flows, in interacting binary systems can be better understood. Questions ! Free format text (please update) Observing_Description: We propose to make spectropolarimetric observations of both TT Hya and V356 Sgr at primary eclipse and at two additional out-of-eclipse phases with the FOS/BL + POL-B and the G190H spectral element. For V356 Sgr one of the outside of eclipse exposures should be between phase 0.1 and 0.2 for comparison with previous FOS and WUPPE observations and the second visit approximately half an orbital phase later. For TT Hya the two outside of eclipse observations should simply be widely separated in phase. We will achieve S/N that will allow measurement of the linear polarization with uncertainties of less than 1\% (required for line studies). We prefer, but do not require, all observations to be within the same orbital cycle for each system. Observations at primary eclipse will consist of one acquisition orbit and two science orbits for a total of 66 minutes of exposure time. Each of the two out-of- eclipse visits will require one acquisition orbit and one (33 min) science orbit. Three visits and 7 orbits will be required for each object, so that a total of 14 orbits are requested for this program. The orbital visibility period and the observing sequence for each object will be identical. One orbit will be required for a standard three-stage ACQ/PEAK (using sequence A+B1+D1 from Table 2-1 of the Cycle 6 FOS Instrument Handbook) to yield a pointing accuracy of 0.12 arcsec. All subsequent 53-minute ``science orbits'' consist of a guide star re-acquisition followed by 33 minutes of 1.0 aperture, POLSCAN=8 observations plus associated overheads. ACQUISITION ORBIT: noindent GS ACQ (8^m); ACQ/PEAK (pattern A) (7^m); ACQ/PEAK (B1) (11^m); ACQ/PEAK (D1) (17^m) SCIENCE ORBIT: noindent GS re-ACQ (6^m); ACCUM O/H (6^m); POLSCAN O/H (8^m); G190H+POL-B (33^m) For TT Hya (the fainter of the two target stars) a representative continuum flux at primary minimum in the G190H spectral region is 1.4times10^-13 \. erg/sec/cm^2/Angstrom; so a typical calculation shows that for this flux level at 2000Angstrom, we will obtain 1.4 counts per diode per sec in each pass direction. Therefore, in 3960 sec (66 min), we expect about 5500 counts or a S/N of about 75 per diode in each pass direction. Three-diode (approximately 5Angstrom) binning yields formal linear polarization accuracies of better than 1 percent. For V356 Sgr, the flux in the G190H region is ~8 times higher (1.1times10^-12\. erg/sec/cm^2/Angstrom) than TT Hya in primary eclipse, but accounting for the ``contamination'' of the unpolarized A-type secondary star (80\% of the total flux in the G190H spectral region) reduces the ``effective'' visibility of the scattered light continuum to a level slightly greater than that of TT Hya. Thus the resulting S/N in the polarization data will be slightly better than that of TT Hya. Lastly, we note that simulations with STScI FOS scattered light modeling software indicate that FOS internal scattered light will not be significant for these observations. Also, no special calibrations are needed for our observations. Real_Time_Justification: As the 2 targets are eclipsing binaries which must be observed during their total eclipse phase, we will require time-critical scheduling. Note that our requested eclipse observations take 2.0 HST (nominal) orbits V356 Sgr has an 8.89 day period with an 10.7 hour (6.7 HST orbits) total phase. This yields 3 or 4 eclipses per month and should not present any substantial difficulty in scheduling. TT Hya has a shorter period and total eclipse phase, , 6.95 days and 5.0 hours (3.1 HST orbits), respectively. This yields more eclipse opportunities, 4 or 5 per month, but a tighter eclipse window. The outside of primary eclipse observations are much less time critical and need to be scheduled at the desired phase plus or minus 1 day for both stars. It is preferred that the observations be executed at primary eclipse and the two additional different orbital phases within the same orbital cycle for each system. Since both binaries appear not to be highly variable either spectroscopically or photometrically, the observations may be scattered over several different orbital cycles. G. J. Peters will apply for time at KPNO on the Coude Feed Telescope to obtain CCD images at HAlpha during the HST observations. This will provide information on the state and location of the cool plasma. Although extensive HAlpha data exist for both systems, long-term monitoring has shown that the amount of material contained in the cool plasma is variable (Peters 1989); therefore contemporaneous optical spectroscopy is warranted. V356 Sgr is currently being spectrophotometrically observed from the ground by Nordsieck, it is expected that these observations will continue and that TT Hya will be added to the program. Calibration_Justification: ! Move appropriate text from Real_Time_Justification Additional_Comments: Fixed_Targets ! Section 5.1 Target_Number: 1 Target_Name: V356-SGR Alternate_Names: Description: STAR, B3-B5 V-IV, A0-A3 III-I, INTERACTING BINARY, ALGOL SYSTEM Position: RA=18H 47M 52.33S +/- 0.5",DEC=-20D 16' 28.0" +/- 0.5", PLATE-ID = 06AL Equinox: J2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: Annual_Parallax: 0.0 Flux: V = 6.85 B-V = 0.16 F(2000)=1.1+/-0.2e-12 Comments: Flux at 2000 specified for primary eclipse. Coordinates determined from gasp images. V and B-V specified are maximum. Minimum values are V=7.68 and B-V=0.24 Coordinates are from Hipparcos catalog with no proper motion included. Target_Number: 2 Target_Name: TT-HYA Alternate_Names: Description: STAR, B6-B9.5 V-IV, K III-I, INTERACTING BINARY, ALGOL SYSTEM Position: RA=11H 13M 12.50S +/- 0.5",DEC=-26D 27' 54.1" +/- 0.5", PLATE-ID = 04NQ Equinox: J2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: Annual_Parallax: 0.0 Flux: V = 7.27 B-V = 0.14 F(2000)=1.4+/-0.2e-13 Comments: Flux at 2000 specified for primary eclipse. Coordinates determined from gasp images. V and B-V specified are maximum. Minimum values are V=9.07 and B-V=0.99 Coordinates are from Hipparcos catalog with no proper motion included. Solar_System_Targets ! Section 5.2 Generic_Targets ! Section 5.3 Scan_Data ! Appendix B ! This is a template for a single visit containing a single exposure ! Repeat exposure and visit blocks as needed Visits Visit_Number: 01 !Visit_Requirements: PERIOD 8.89610D AND ZERO-PHASE JD2441800.542 ! SEQ 1-2 WITHIN 9.0D Visit_Requirements: PERIOD 8.89610D AND ZERO-PHASE JD2441804.99005 SEQ 1-2 WITHIN 9.0D ORIENT 265D TO 265D On_Hold_Comments: Visit_Comments: Exposure_Number: 1 Target_Name: V356-SGR Config: FOS/BL Opmode: ACQ/PEAK Aperture: 4.3 Sp_Element: G190H Wavelength: Optional_Parameters: SEARCH-SIZE-X=1 SEARCH-SIZE-Y=3 SCAN-STEP-Y=1.23 Number_of_Iterations: 1 Time_Per_Exposure: 1S Special_Requirements: ONBOARD ACQ FOR 2 Comments: Exposure_Number: 2 Target_Name: V356-SGR Config: FOS/BL Opmode: ACQ/PEAK Aperture: 1.0 Sp_Element: G190H Wavelength: Optional_Parameters: SEARCH-SIZE-X=6 SEARCH-SIZE-Y=2 SCAN-STEP-X=0.602 SCAN-STEP-Y=0.602 Number_of_Iterations: 1 Time_Per_Exposure: 1S Special_Requirements: ONBOARD ACQ FOR 3 Comments: Exposure_Number: 3 Target_Name: V356-SGR Config: FOS/BL Opmode: ACQ/PEAK Aperture: 0.5 Sp_Element: G190H Wavelength: Optional_Parameters: SEARCH-SIZE-X=3 SEARCH-SIZE-Y=3 SCAN-STEP-X=0.29 SCAN-STEP-Y=0.29 Number_of_Iterations: 1 Time_Per_Exposure: 1S Special_Requirements: ONBOARD ACQ FOR 4 Comments: Exposure_Number: 4 Target_Name: V356-SGR Config: FOS/BL Opmode: ACQ/PEAK Aperture: 0.3 Sp_Element: G190H Wavelength: Optional_Parameters: SEARCH-SIZE-X=3 SEARCH-SIZE-Y=3 SCAN-STEP-X=0.172 SCAN-STEP-Y=0.172 Number_of_Iterations: 1 Time_Per_Exposure: 3S Special_Requirements: ONBOARD ACQ FOR 20-30 SAVE OFFSET FROSTY Comments: Exposure_Number: 20 Target_Name: V356-SGR Config: FOS/BL Opmode: ACCUM Aperture: 1.0 Sp_Element: G190H Wavelength: Optional_Parameters: POLSCAN=8B Number_of_Iterations: 1 Time_Per_Exposure: 1840S !Special_Requirements: PHASE 0.9865 TO 0.0045 Special_Requirements: PHASE 0.4865 TO 0.5045 MIN DUR MAX DUR Comments: IDEAL IF STARTS AT PHASE 0.0025 (0.5025) Exposure_Number: 30 Target_Name: V356-SGR Config: FOS/BL Opmode: ACCUM Aperture: 1.0 Sp_Element: G190H Wavelength: Optional_Parameters: POLSCAN=8B Number_of_Iterations: 1 Time_Per_Exposure: 1880S Special_Requirements: MIN DUR MAX DUR Comments: Visit_Number: 02 Visit_Requirements: PERIOD 8.89610D AND ZERO-PHASE JD2441800.542 ORIENT 265D TO 265D On_Hold_Comments: Visit_Comments: Observe at approx phase=0.4, if not possible then use on-hold Visit 03 which observes at approx phase=0.6 Exposure_Number: 4 Target_Name: V356-SGR Config: FOS/BL Opmode: ACQ/PEAK Aperture: 0.3 Sp_Element: G190H Wavelength: Optional_Parameters: SEARCH-SIZE-X=3 SEARCH-SIZE-Y=3 SCAN-STEP-X=0.172 SCAN-STEP-Y=0.172 Number_of_Iterations: 1 Time_Per_Exposure: 3S Special_Requirements: ONBOARD ACQ FOR 20 USE OFFSET FROSTY Comments: Exposure_Number: 20 Target_Name: V356-SGR Config: FOS/BL Opmode: ACCUM Aperture: 1.0 Sp_Element: G190H Wavelength: Optional_Parameters: POLSCAN=8B Number_of_Iterations: 1 Time_Per_Exposure: 700S Special_Requirements: USE OFFSET FROSTY PHASE 0.30 TO 0.40 Comments: Visit_Number: 03 Visit_Requirements: PERIOD 8.89610D AND ZERO-PHASE JD2441800.542 SEQ 1,3 WITHIN 9.0D ORIENT 265D TO 265D On_Hold_Comments: Visit_Comments: Observe at approx phase=0.6, ONLY if Visit 02 cannot be scheduled. Exposure_Number: 4 Target_Name: V356-SGR Config: FOS/BL Opmode: ACQ/PEAK Aperture: 0.3 Sp_Element: G190H Wavelength: Optional_Parameters: SEARCH-SIZE-X=3 SEARCH-SIZE-Y=3 SCAN-STEP-X=0.172 SCAN-STEP-Y=0.172 Number_of_Iterations: 1 Time_Per_Exposure: 3S Special_Requirements: ONBOARD ACQ FOR 20 USE OFFSET FROSTY Comments: Exposure_Number: 20 Target_Name: V356-SGR Config: FOS/BL Opmode: ACCUM Aperture: 1.0 Sp_Element: G190H Wavelength: Optional_Parameters: POLSCAN=8B Number_of_Iterations: 1 Time_Per_Exposure: 700S Special_Requirements: USE OFFSET FROSTY PHASE 0.55 TO 0.65 Comments: Visit_Number: 04 Visit_Requirements: PERIOD 6.95342913D AND ZERO-PHASE JD2445475.6870 On_Hold_Comments: Visit_Comments: Exposure_Number: 1 Target_Name: TT-HYA Config: FOS/BL Opmode: ACQ/PEAK Aperture: 4.3 Sp_Element: G190H Wavelength: Optional_Parameters: SEARCH-SIZE-X=1 SEARCH-SIZE-Y=3 SCAN-STEP-Y=1.23 Number_of_Iterations: 1 Time_Per_Exposure: 1S Special_Requirements: ONBOARD ACQ FOR 2 Comments: Exposure_Number: 2 Target_Name: TT-HYA Config: FOS/BL Opmode: ACQ/PEAK Aperture: 1.0 Sp_Element: G190H Wavelength: Optional_Parameters: SEARCH-SIZE-X=6 SEARCH-SIZE-Y=2 SCAN-STEP-X=0.602 SCAN-STEP-Y=0.602 Number_of_Iterations: 1 Time_Per_Exposure: 1S Special_Requirements: ONBOARD ACQ FOR 3 Comments: Exposure_Number: 3 Target_Name: TT-HYA Config: FOS/BL Opmode: ACQ/PEAK Aperture: 0.5 Sp_Element: G190H Wavelength: Optional_Parameters: SEARCH-SIZE-X=3 SEARCH-SIZE-Y=3 SCAN-STEP-X=0.29 SCAN-STEP-Y=0.29 Number_of_Iterations: 1 Time_Per_Exposure: 1S Special_Requirements: ONBOARD ACQ FOR 4 Comments: Exposure_Number: 4 Target_Name: TT-HYA Config: FOS/BL Opmode: ACQ/PEAK Aperture: 0.3 Sp_Element: G190H Wavelength: Optional_Parameters: SEARCH-SIZE-X=3 SEARCH-SIZE-Y=3 SCAN-STEP-X=0.172 SCAN-STEP-Y=0.172 Number_of_Iterations: 1 Time_Per_Exposure: 3S Special_Requirements: ONBOARD ACQ FOR 20-30 Comments: Exposure_Number: 20 Target_Name: TT-HYA Config: FOS/BL Opmode: ACCUM Aperture: 1.0 Sp_Element: G190H Wavelength: Optional_Parameters: POLSCAN=8B Number_of_Iterations: 1 ! Time_Per_Exposure: 2090S Time_Per_Exposure: 1900S Special_Requirements: PHASE 0.984 TO 0.994 MAX DUR 200% Comments: Exposure_Number: 30 Target_Name: TT-HYA Config: FOS/BL Opmode: ACCUM Aperture: 1.0 Sp_Element: G190H Wavelength: Optional_Parameters: POLSCAN=8B Number_of_Iterations: 1 Time_Per_Exposure: 2090S Special_Requirements: MAX DUR 200% Comments: ! Uncomment or copy visit level special requirements needed ! Most of these requirements (including ORIENT) will limit scheduling ! PCS MODE [Fine | Gyro] ! GUIDing TOLerance ! DROP TO GYRO IF NECESSARY [NO REACQuisition] ! ORIENTation TO ! ORIENTation TO FROM ! ORIENTation TO FROM NOMINAL ! SAME ORIENTation AS ! CVZ ! PARallel ! SCHEDulability ! AFTER [BY [TO ]] ! AFTER ! BEFORE ! BETWEEN AND ! GROUP WITHIN