17092( 5) - 02-Aug-2023 15:08:28 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 17092 Version: 5 Check-in Time: 02-Aug-2023 15:08:28 STScI Edit Number: 0 Title Calibrating STIS Coronagraphic Spectroscopy for High Contrast Observations ------------------------------------------------------------------------------------ Type Cycle GO 30 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Kimberly Ward-Duong Smith College Y CoI: Dr. John Henry Debes Space Telescope Science Institute - ESA - N JWST CoI: Dr. Jonathan Aguilar Space Telescope Science Institute N CoI: William Balmer The Johns Hopkins University N CoI: Dr. Katherine Brutlag Follette Amherst College N CoI: Jingyi Zhang Smith College N ------------------------------------------------------------------------------------ Abstract The Space Telescope Imaging Spectrograph (STIS) is currently the world's only available visible-light coronagraphic spectroscopy facility. The unique capabilities of R~500 optical spectroscopy at close angular separation (0.05-0.3") from a bright central object has been relatively unexplored with this mode and to-date are not yet fully calibrated. The goal of this program is to assess the achievable contrast, inner working angle, and fidelity of extracted spectra using the occulting fiducial F1 bar in the STIS 52x0.2 spectroscopic aperture. Targets will be two well-measured single A0V standard stars, in addition to a binary white dwarf companion system and PSF reference, wherein the faint companion has published images and low-resolution spectra against which STIS observations will be compared. Use of target offsets from the nominal bar acquisition positions, pushing the star as close as possible to the edge of the occulter, will allow us to determine the limits of coronagraphic performance achievable with this mode. The driving science benefit to the community is to provide well-calibrated contrast curves, an understanding of the noise properties and quality of extracted spectra in this mode. These measurements would have immediate utility for programs involving spectroscopy of imaged exoplanets, brown dwarfs, and close binary companions; circumstellar disks; jet-launching regions in young protostars; and AGN jets and host environments (i.e., any scientific case where optical spectra at very small angular separations are of interest). The proposed program will explore and calibrate the full capabilities of this unique mode made possible only with HST/STIS. ------------------------------------------------------------------------------------ Observations Description ------------------------ ----------------------------- Overview ----------------------------- This calibration program involves six orbits to measure and calibrate the performance of the coronagraphic spectroscopy mode of STIS, via two main experiments: 17092( 5) - 02-Aug-2023 15:08:28 - [ 2] 1) Contrast Test: This experiment serves to determine the achievable contrast of the coronagraphic spectroscopy mode, involving observations of two early-type (A2V) stars, TYC 1262-187-1 and HD283593. These stars will each be acquired in imaging mode, then placed within the fiducial 52x0.2F1 aperture behind the F1 coronagraphic occulting bar. Then, each star will be offset toward the edge of bar by 100 mas or 200 mas using POS-TARGs, and deep observations will be taken in order to determine the sensitivity of the extracted spectra at close angular separation from the star. The stars will need to be observed in a standard coronagraphic sequence, i.e., in adjacent orbits. This is required to minimize the effects of breathing due to thermal fluctuations across the telescope structure, which has significant effects on PSF quality. The two observations will be used as calibration observations (PSF references) for each other in order to subtract the starlight in each exposure and allow deep observations of the circumstellar surroundings, and thus they may be observed in any order. 2) Spectral Extraction Test: This experiment is designed to assess the fidelity of the extracted spectra at close angular separation (0.45") from the star. The target is a binary system consisting of a G-type star (HD114174) and its well-characterized white dwarf companion. The primary G-type star will be placed at the fiducial 52x0.2F1 position behind the bar with a designated ORIENT angle to place the white dwarf companion within the spectroscopic slit. Along with the binary, a PSF reference target of similar spectral type (HD115692) will be observed to subtract the PSF and recover the spectrum of the white dwarf by removing contributed starlight from the primary G-star behind the coronagraphic bar. ----------------------------- 2) Visit Structure ----------------------------- For the Contrast Test, we will obtain deep observations of each star at two separate POS-TARG offset positions. Given that the targets are isolated stars, no specific ORIENT angles are required. The observations are designed to be executed in subsequent orbits. For the Spectral Test, the binary system must be observed in subsequent orbits with the PSF reference. ----------------------------- ORIENT Constraints ----------------------------- This visit involves placing a close faint white dwarf companion to the primary star within the slit. The companion is predicted to be at a position angle of 178.5 deg and separation of ~0.45 arcsec (as of August 2023 based upon RV and astrometric orbital analysis, including an imaging epoch as recent as July 2022 with JWST), and the companion is moving closer to the primary star. Given the 45 deg relative angle of the STIS detector to the +U3 axis and the additional 1.3 deg offset to the 52x0.2F1 slit, we therefore request the ORIENT constraint 17092( 5) - 02-Aug-2023 15:08:28 - [ 3] to be within one of two sets of possible 20 degree ranges to place the companion either directly above or below the occulting bar within the slit (~225 +/- 10 deg. or ~45 +/- 10 deg., respectively). ----------------------------- Guide Stars ----------------------------- For stability with the PSF reference subtraction in both experiments, we require pointing and roll control with 2-FGS guiding. Single-FGS guiding is not sufficiently stable to perform PSF subtraction for coronagraphic spectroscopy. ------------------------------------------------------------------------------------ 17092( 5) - 02-Aug-2023 15:08:28 - [ 4] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 TYC-1262-187 STAR, F0-F2 RA=04H00M35.1678S, J2000 V = 10.13 -1 DEC=+21D51'49.70" Reference Frame: ICRS Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 -2.853946194111909E-4 -0.003800000058618025 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 2 HD-283593 STAR, A0-A3 V-IV RA=04H19M3.6931S, J2000 V = 9.81 DEC=+25D57'11.03" Reference Frame: ICRS Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000.0 3.5959768250150615E-5 -0.004554999986794428 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 3 HD-114174 STAR, DC, G V-IV RA=13H08M51.0230S, J2000 V = 6.81 DEC=+05D12'26.07" Reference Frame: ICRS Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000.0 0.0057258041935138075 -0.680324000040855 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 4 HD-115692 STAR, G V-IV RA=13H18M41.7563S, J2000 V = 8.466 DEC=+07D11'11.57" Reference Frame: ICRS Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000.0 -0.01113588792738884 0.052937 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 17092( 5) - 02-Aug-2023 15:08:28 - [ 5] Visit: 01 (Contrast Test) Visit Requirements: GROUP 01, 02 WITHIN 4 Orbits On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 TYC-1262-18 STIS/CCD ACQ F25ND3 MIRROR 1 1 S (1 S) 7-1 ------------------------------------------------------------------------------------------------------------------------------------ 2 TYC-1262-18 STIS/CCD ACCUM 52X0.2E1 G750L 7751 1 40 S (40 7-1 S) Comments: Using the E1 pseudo-aperture to avoid CTE effects. ------------------------------------------------------------------------------------------------------------------------------------ 3 TYC-1262-18 STIS/CCD ACCUM 52X0.2F1 G750L 7751 CR-SPLIT=4, GAIN=4 1 1916 S POS TARG null, 0.100 7-1 (1916 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 TYC-1262-18 STIS/CCD ACCUM 52X0.2F1 G750L 7751 CR-SPLIT=4, GAIN=4 1 2504 S POS TARG null, 0.200 7-1 (2504 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 CCDFLAT STIS/CCD ACCUM 52X0.2F1 G750L 7751 2 DEF (0 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ TYC-1262-187-1 1 STIS/CCD ACQ F25ND3 MIRROR none none none none 1 N/A TYC-1262-187-1 2 STIS/CCD ACCUM 52X0.2E1 G750L 7751 none none none 1 1 N/A TYC-1262-187-1 2 STIS/CCD ACCUM 52X0.2E1 G750L 7751 none none none 2 1 N/A TYC-1262-187-1 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 1 1 N/A TYC-1262-187-1 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 2 1 N/A TYC-1262-187-1 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 3 1 N/A TYC-1262-187-1 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 4 1 N/A TYC-1262-187-1 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 1 2 N/A TYC-1262-187-1 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 2 2 N/A TYC-1262-187-1 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 3 2 N/A TYC-1262-187-1 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 4 2 N/A CCDFLAT 5 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none 1 none 2 N/A CCDFLAT 5 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none 2 none 2 N/A 17092( 5) - 02-Aug-2023 15:08:28 - [ 6] Visit: 02 (Contrast Test) Visit Requirements: GROUP 02, 01 WITHIN 4 Orbits On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 HD-283593 STIS/CCD ACQ 50CCD MIRROR 1 1 S (1 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 HD-283593 STIS/CCD ACCUM 52X0.2E1 G750L 7751 1 30 S (30 S) Comments: Using the E1 pseudo-aperture to avoid CTE effects. ------------------------------------------------------------------------------------------------------------------------------------ 3 HD-283593 STIS/CCD ACCUM 52X0.2F1 G750L 7751 CR-SPLIT=5, GAIN=4 1 1934 S POS TARG null, 0.100 (1934 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 HD-283593 STIS/CCD ACCUM 52X0.2F1 G750L 7751 CR-SPLIT=5, GAIN=4 1 2464 S POS TARG null, 0.200 (2464 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 CCDFLAT STIS/CCD ACCUM 52X0.2F1 G750L 7751 2 DEF (0 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ HD-283593 1 STIS/CCD ACQ 50CCD MIRROR none none none none 1 N/A HD-283593 2 STIS/CCD ACCUM 52X0.2E1 G750L 7751 none none none 1 1 N/A HD-283593 2 STIS/CCD ACCUM 52X0.2E1 G750L 7751 none none none 2 1 N/A HD-283593 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 1 1 N/A HD-283593 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 2 1 N/A HD-283593 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 3 1 N/A HD-283593 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 4 1 N/A HD-283593 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 5 1 N/A HD-283593 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 1 2 N/A HD-283593 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 2 2 N/A HD-283593 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 3 2 N/A HD-283593 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 4 2 N/A HD-283593 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 5 2 N/A CCDFLAT 5 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none 1 none 2 N/A CCDFLAT 5 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none 2 none 2 N/A 17092( 5) - 02-Aug-2023 15:08:28 - [ 7] Visit: 03 (Spectral Test) Visit Requirements: ORIENT 215D TO 235 D; ORIENT 35D TO 55 D; GROUP 03, 04 WITHIN 2 Orbits On Hold Comments: Additional Comments: This visit involves placing a close faint white dwarf companion to the primary star within the slit. The companion is predicted to be at a position angle of 178.5 deg and separation of ~0.45 arcsec (as of August 2023), and is moving closer to the primary star. Given the 45 deg relative angle of the STIS detector to the +U3 axis and the additional 1.3 deg offset to the 52x0.2F1 slit, we therefore request the ORIENT constraint to be within one of two sets of possible 20 degree ranges to place the companion either directly above or below the occulting bar within the slit (~225 deg. or ~45 deg., respectively). Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 HD-114174 STIS/CCD ACQ F25ND5 MIRROR 1 10 S (10 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 HD-114174 STIS/CCD ACCUM 52X0.2E1 G750L 7751 1 1.5 S (1.5 S) Comments: Using the E1 pseudo-aperture to avoid CTE effects. ------------------------------------------------------------------------------------------------------------------------------------ 3 HD-114174 STIS/CCD ACCUM 52X0.2F1 G750L 7751 CR-SPLIT=8, GAIN=4 1 1637 S (1637 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 CCDFLAT STIS/CCD ACCUM 52X0.2F1 G750L 7751 2 DEF (0 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ HD-114174 1 STIS/CCD ACQ F25ND5 MIRROR none none none none 1 N/A HD-114174 2 STIS/CCD ACCUM 52X0.2E1 G750L 7751 none none none 1 1 N/A HD-114174 2 STIS/CCD ACCUM 52X0.2E1 G750L 7751 none none none 2 1 N/A HD-114174 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 1 1 N/A HD-114174 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 2 1 N/A HD-114174 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 3 1 N/A HD-114174 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 4 1 N/A HD-114174 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 5 1 N/A HD-114174 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 6 1 N/A HD-114174 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 7 1 N/A HD-114174 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 8 1 N/A CCDFLAT 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none 1 none 1 N/A CCDFLAT 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none 2 none 1 N/A 17092( 5) - 02-Aug-2023 15:08:28 - [ 8] Visit: 04 (Spectral Test) Visit Requirements: GROUP 04, 03 WITHIN 2 Orbits On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 HD-115692 STIS/CCD ACQ F25ND3 MIRROR 1 1 S (1 S) Comments: Revised 2023-07-27 to use F25ND3 aperture based upon corrected ETC calculations ------------------------------------------------------------------------------------------------------------------------------------ 2 HD-115692 STIS/CCD ACCUM 52X0.2E1 G750L 7751 1 2 S (2 S) Comments: Using the E1 pseudo-aperture to avoid CTE effects. ------------------------------------------------------------------------------------------------------------------------------------ 3 HD-115692 STIS/CCD ACCUM 52X0.2F1 G750L 7751 CR-SPLIT=2, GAIN=4 1 1940 S (1940 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 CCDFLAT STIS/CCD ACCUM 52X0.2F1 G750L 7751 2 DEF (0 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ HD-115692 1 STIS/CCD ACQ F25ND3 MIRROR none none none none 1 N/A HD-115692 2 STIS/CCD ACCUM 52X0.2E1 G750L 7751 none none none 1 1 N/A HD-115692 2 STIS/CCD ACCUM 52X0.2E1 G750L 7751 none none none 2 1 N/A HD-115692 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 1 1 N/A HD-115692 3 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none none 2 1 N/A CCDFLAT 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none 1 none 1 N/A CCDFLAT 4 STIS/CCD ACCUM 52X0.2F1 G750L 7751 none none 2 none 1 N/A 17092( 5) - 02-Aug-2023 15:08:28 - [ 9] Summary Form for Proposal 17092 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 50CCD, 52X0.2E1, 52X0.2F1, F25ND3, F25ND5 ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, ACQ ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=2, CR-SPLIT=4, CR-SPLIT=5, CR-SPLIT=8, GAIN=4 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GROUP 01, 02 WITHIN 4 Orbits, GROUP 02, 01 WITHIN 4 Orbits, GROUP 03, 04 WITHIN 2 Orbits, GROUP 04, 03 WITHIN 2 Orbits, ORIENT 215D TO 235 D, ORIENT 35D TO 55 D, POS TARG null, 0.100, POS TARG null, 0.200 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements G750L, MIRROR ------------------------------------------------------------------------------------------------------------------------------------ Target Names CCDFLAT, HD-114174, HD-115692, HD-283593, TYC-1262-187-1 ------------------------------------------------------------------------------------------------------------------------------------