15487( 4) - 07-Dec-2018 20:32:29 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 15487 Version: 4 Check-in Time: 07-Dec-2018 20:32:29 STScI Edit Number: 1 Title Standard Stars for the JWST Mission and CALSPEC Legacy ------------------------------------------------------------------------------------ Type Cycle GO/DD 25 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Ralph C. Bohlin Space Telescope Science Institute Y CoI: Dr. Karl D. Gordon Space Telescope Science Institute N CoI: Dr. Susana E. Deustua Space Telescope Science Institute N CoI: Dr. George Rieke University of Arizona N CoI: Dr. Linda J. Smith Space Telescope Science Institute - ESA N CoI: Dr. Kevin Volk Space Telescope Science Institute N CoI: Greg Sloan Space Telescope Science Institute N CoI: Dr. Kathleen E. Kraemer Boston College N CoI: Dr. Martha L. Boyer Space Telescope Science Institute N CoI: Dr. Stacey N Bright Space Telescope Science Institute N CoI: Dr. Dean C. Hines Space Telescope Science Institute N ------------------------------------------------------------------------------------ Abstract Stellar standards are required for JWST, WFIRST, and LUVOIR flux calibrations and for the science programs of the general astronomical community. In particular, measuring the relative fluxes of redshifted supernovae Ia's is essential for determining the nature of the dark energy that is driving the observed accelerating cosmic expansion. The precision of determining the cosmological constants is tied directly to the precision of the relative flux calibration as a function of wavelength. The CALSPEC archive of HST/STIS spectral energy distributions (SEDs) has become the reference gold-standard database for the best fundamental flux standards that are currently available. This proposal will significantly improve the legacy value of CALSPEC by verifying the utility of the several WD standards that have been established by fitting WD models to WFC3 photometry and will extend the CALSPEC archive to standards fainter by about 3 mag. ------------------------------------------------------------------------------------ Observations Description ------------------------ The limit of STIS dynamic range is around V=16, while fainter standards are required for larger telescopes, eg. LSST and Pan-STARRS. This void is being filled by the A. Saha HST programs 12967, 13711, and 15113, which observes WD stars and models ground-based spectra of their Balmer lines to determine Teff and log g. Then, WD models fitted to WFC3 photometry determine absolute SEDs that include interstellar extinction effects (Narayan et al. 2016). The brightest of the Saha program WDs, SDSS J151421 at Sloan g=15.7, requires only 2 STIS orbits and will produce a new CALSPEC standard that provides an essential, minimal confirmation and an error estimate for the model fitting techniques of the Saha pro- gram. The STIS SED provides a more precise constraint on extinction from the interstellar Dust than is currently possible with the Saha program of WFC3 broadband photometry. This verification is 15487( 4) - 07-Dec-2018 20:32:29 - [ 2] essential for certifying the Saha WDs as precise flux standards that are worthy of inclusion in CALSPEC. ------------------------------------------------------------------------------------ 15487( 4) - 07-Dec-2018 20:32:29 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 19 SDSSJ151421. STAR, DA RA=15H14M21.2800S, J2000 V = 16.5 27+004752.8 DEC=+00D47'52.88" Reference Frame: ICRS Extended: NO 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 -2.0001940080769791E-4 -0.028 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 15487( 4) - 07-Dec-2018 20:32:29 - [ 4] Visit: 01 (SDSS151421) Visit Requirements: BEFORE 15-JUN-2019:00:00:00 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 SDSSJ151421 STIS/CCD ACQ F28X50LP MIRROR 1 3 S (3 S) .27+004752. 8 ------------------------------------------------------------------------------------------------------------------------------------ 2 NONE STIS MSMOFF SETOFFSET=ZERO, GRATING1=ALL 1 DEF (0 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 SDSSJ151421 STIS/FUV ACCUM 52X2 G140L 1425 WAVECAL=NO 1 950 S (950 .27+004752. -MAMA S) 8 ------------------------------------------------------------------------------------------------------------------------------------ 4 WAVE STIS/FUV ACCUM 52X0.05 G140L 1425 1 DEF (0 S) -MAMA ------------------------------------------------------------------------------------------------------------------------------------ 5 SDSSJ151421 STIS/NUV ACCUM 52X2 G230L 2376 WAVECAL=NO 1 964 S (964 .27+004752. -MAMA S) 8 ------------------------------------------------------------------------------------------------------------------------------------ 6 WAVE STIS/NUV ACCUM 31X0.05ND G230L 2376 1 DEF (0 S) -MAMA C ------------------------------------------------------------------------------------------------------------------------------------ 7 NONE STIS MSMOFF SETOFFSET=RESTORE, 1 DEF (0 S) GRATING1=ALL ------------------------------------------------------------------------------------------------------------------------------------ 8 WAVE STIS/CCD ACCUM 52X0.1 G430L 4300 1 DEF (0 S) SEQ 8-12 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 9 SDSSJ151421 STIS/CCD ACCUM 52X2E1 G430L 4300 CR-SPLIT=2, GAIN=1, WAVECAL=NO 1 500 S (500 .27+004752. S) 8 ------------------------------------------------------------------------------------------------------------------------------------ 10 SDSSJ151421 STIS/CCD ACCUM 52X2 G750L 7751 CR-SPLIT=4, GAIN=1, WAVECAL=NO 1 1856 S .27+004752. (1856 S) 8 Comments: Manual fringe flat used instead of default to get higher S/N. ------------------------------------------------------------------------------------------------------------------------------------ 11 WAVE STIS/CCD ACCUM 52X0.1 G750L 7751 1 DEF (0 S) ------------------------------------------------------------------------------------------------------------------------------------ 12 NONE STIS/CCD ACCUM 0.3X0.09 G750L 7751 LAMP=TUNGSTEN, GAIN=4 4 120 S (480 S) ------------------------------------------------------------------------------------------------------------------------------------ 15487( 4) - 07-Dec-2018 20:32:29 - [ 5] 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 | ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDSSJ151421.27+0047 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A 52.8 NONE 2 STIS MSMOFF none none none none 1 N/A SDSSJ151421.27+0047 3 STIS/FUV ACCUM 52X2 G140L 1425 none none none none 1 N/A 52.8 -MAMA WAVE 4 STIS/FUV ACCUM 52X0.05 G140L 1425 none none none none 1 N/A -MAMA SDSSJ151421.27+0047 5 STIS/NUV ACCUM 52X2 G230L 2376 none none none none 1 N/A 52.8 -MAMA WAVE 6 STIS/NUV ACCUM 31X0.05N G230L 2376 none none none none 1 N/A -MAMA DC NONE 7 STIS MSMOFF none none none none 1 N/A WAVE 8 STIS/CCD ACCUM 52X0.1 G430L 4300 none none none none 2 N/A SDSSJ151421.27+0047 9 STIS/CCD ACCUM 52X2E1 G430L 4300 none none none 1 2 N/A 52.8 SDSSJ151421.27+0047 9 STIS/CCD ACCUM 52X2E1 G430L 4300 none none none 2 2 N/A 52.8 SDSSJ151421.27+0047 10 STIS/CCD ACCUM 52X2 G750L 7751 none none none 1 2 N/A 52.8 SDSSJ151421.27+0047 10 STIS/CCD ACCUM 52X2 G750L 7751 none none none 2 2 N/A 52.8 SDSSJ151421.27+0047 10 STIS/CCD ACCUM 52X2 G750L 7751 none none none 3 2 N/A 52.8 SDSSJ151421.27+0047 10 STIS/CCD ACCUM 52X2 G750L 7751 none none none 4 2 N/A 52.8 WAVE 11 STIS/CCD ACCUM 52X0.1 G750L 7751 none none none none 2 N/A NONE 12 STIS/CCD ACCUM 0.3X0.09 G750L 7751 none none 1 none 2 N/A NONE 12 STIS/CCD ACCUM 0.3X0.09 G750L 7751 none none 2 none 2 N/A NONE 12 STIS/CCD ACCUM 0.3X0.09 G750L 7751 none none 3 none 2 N/A NONE 12 STIS/CCD ACCUM 0.3X0.09 G750L 7751 none none 4 none 2 N/A 15487( 4) - 07-Dec-2018 20:32:29 - [ 6] Summary Form for Proposal 15487 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 0.3X0.09, 31X0.05NDC, 52X0.05, 52X0.1, 52X2, 52X2E1, F28X50LP ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS, STIS/CCD, STIS/FUV-MAMA, STIS/NUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, ACQ, MSMOFF ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=2, CR-SPLIT=4, GAIN=1, GAIN=4, GRATING1=ALL, LAMP=TUNGSTEN, SETOFFSET=RESTORE, SETOFFSET=ZERO, WAVECAL=NO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BEFORE 15-JUN-2019:00:00:00, SEQ 8-12 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements G140L, G230L, G430L, G750L, MIRROR ------------------------------------------------------------------------------------------------------------------------------------ Target Names NONE, SDSSJ151421.27+004752.8, WAVE ------------------------------------------------------------------------------------------------------------------------------------