13849( 3) - 09-Jul-2014 15:06:24 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 13849 Version: 3 Check-in Time: 09-Jul-2014 15:06:24 STScI Edit Number: 2 Title The parallax and mass of the binary classical Cepheid V1334 Cyg ------------------------------------------------------------------------------------ Type Cycle GO 22 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Pierre Kervella Observatoire de Paris Y CoI: Dr. Nancy R. Evans Smithsonian Institution Astrophysical Y Observatory CoI: Dr. Edmund Nelan Space Telescope Science Institute Y CoI: Dr. Charles R. Proffitt Computer Sciences Corporation Y CoI: Dr. Alexandre Gallenne Universidad de Concepcion N CoI: Dr. Antoine Merand European Southern Observatory - Chile N CoI: Prof. John D. Monnier University of Michigan N ------------------------------------------------------------------------------------ Abstract V1334 Cyg is a short-period classical Cepheid, and the primary star ("A") of a binary system. Using the CHARA interferometer, we spatially resolved its companion ("B") for the first time at an angular separation of 8 mas (Gallenne et al. 2013). Our two epochs clearly show the orbital displacement of B on its 5.3-year orbit, relative to the Cepheid, with an astrometric accuracy of 30 microas. This observation opens the exciting opportunity to determine the orbital parallax of this system. Based on the existing long-term radial velocimetry of A, and our interferometric data, we already derived the main orbital parameters of the system. However, we face a degeneracy between the mass ratio of the two stars and the distance. We miss the radial velocity of B (V1334 Cyg is still an SB1) or the orbital trajectory of the Cepheid around the center-of-mass. To waive this degeneracy, we request FGS astrometry and STIS high resolution spectroscopy. The FGS observations will trace the apparent orbital trajectory of A on the sky (to 0.1 mas accuracy), and the high-resolution STIS spectroscopy will give us the radial velocity of B (to < 1 km/s). The spectral disentangling of A and B is impossible in the visible due to the high contrast between A and B in this wavelength domain. In the UV, the companion flux dominates the Cepheid, thanks to its early spectral type (~B5V), and the disentangling is a lot easier. Combining STIS and FGS with CHARA interferometry, our goal is to obtain in 3 years the parallax and mass of the Cepheid with an unbiased accuracy of 1%. This will set a solid fiducial point for the calibration of fundamental Cepheid relations (period-luminosity, mass-period, ...). ------------------------------------------------------------------------------------ Observations Description ------------------------ The STIS observations aim at obtaining the spectrum and deriving the radial velocity of the hot companion V1334 Cyg B (hereafter "B") of the Cepheid. Contrary to the visible domain, the spectrum of B dominates the composite spectrum in the UV. The observations themselves do not present a particular technical difficulty. They will be repeated every year for 3 years, once per 13849( 3) - 09-Jul-2014 15:06:24 - [ 2] cycle, starting in September 2014. The minimum radial velocity will occur in 2014, and the maximum radial velocity will occur in 2016. The FGS observations are scheduled yearly in late July/early August starting in 2013 for 4 epochs. This relatively tight constraing in observing date is intended to obtain observations with always the same parallax factor. As the first observing epoch will occur shortly before the start of Cycle 21 observations, we submitted a change request (reference number 74730) that was approved. ------------------------------------------------------------------------------------ 13849( 3) - 09-Jul-2014 15:06:24 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 V1334-CYG STAR, B3-B5 V-IV, RA=21H19M22.1800S +/- 0.01", J2000 V = -2 V = 5.893 +/- 0.10 FLAM(1400)=1e-11; CEPHEID, COMPOSITE DEC=+38D14'14.91" +/- 0.01" FLAM(1565)=8.47e-11; SPECTRAL TYPE, F0-F2 FLAM(2365)=4.90e-12 Reference Frame: ICRS Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 -4.158962784400882E-5 -0.00229 0.00151 ------------------------------------------------------------------------------------------------------------------------------------ 2 V1334-REF2 CALIBRATION, RA=21H19M27.7420S +/- 1", J2000 V = 12.29 +/- 0.1 ASTROMETRIC DEC=+38D14'27.38" +/- 1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 3 V1334-REF3 CALIBRATION, RA=21H19M28.9660S +/- 1", J2000 V = 13.74 +/- 0.1 ASTROMETRIC DEC=+38D13'24.13" +/- 1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 4 V1334-REF4 CALIBRATION, RA=21H19M24.5597S +/- 1", J2000 V = 12.14 +/- 0.1 ASTROMETRIC DEC=+38D11'27.45" +/- 1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 5 V1334-REF5 CALIBRATION, RA=21H19M15.7270S +/- 1", J2000 V = 13.59 +/- 0.1 ASTROMETRIC DEC=+38D14'38.54" +/- 1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 6 V1334-REF6 CALIBRATION, RA=21H19M23.8340S +/- 1", J2000 V = 12.33 +/- 0.1 ASTROMETRIC DEC=+38D18'1.91" +/- 1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 7 V1334-REF7 CALIBRATION, RA=21H19M21.1202S +/- 1", J2000 V = 12.60 +/- 0.2 ASTROMETRIC DEC=+38D19'28.52" +/- 1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 8 V1334-REF8 CALIBRATION, RA=21H19M12.8604S +/- 1", J2000 V = 8.83 +/- 0.2 ASTROMETRIC DEC=+38D09'47.90" +/- 1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 9 V1334-REF9 CALIBRATION, RA=21H19M6.0329S +/- 1", J2000 V = 11.52 +/- 0.2 ASTROMETRIC DEC=+38D08'34.45" +/- 1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 10 V1334-REF10 CALIBRATION, RA=21H19M27.7400S +/- 1", J2000 V = 14.47 +/- 0.2 ASTROMETRIC DEC=+38D14'26.90" +/- 1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 11 V1334-REF11 CALIBRATION, RA=21H19M17.1151S +/- 1", J2000 V = 12.60 +/- 0.2 ASTROMETRIC DEC=+38D13'14.08" +/- 1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 13849( 3) - 09-Jul-2014 15:06:24 - [ 4] Visit: 01 Visit Requirements: ORIENT 187D TO 189 D; BETWEEN 06-AUG-2015 AND 09-AUG-2015 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 V1334-CYG FGS POS 1 F5ND 1 2 S (2 S) SEQ 1-34 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ 2 V1334-REF2 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 3 V1334-REF9 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 4 V1334-REF8 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 5 V1334-REF4 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 6 V1334-REF3 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 7 V1334-CYG FGS POS 1 F5ND 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 8 V1334-REF7 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 9 V1334-REF6 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 10 V1334-REF2 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 11 V1334-CYG FGS POS 1 F5ND 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 12 V1334-REF2 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 13 V1334-REF5 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 14 V1334-REF11 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 15 V1334-REF9 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 16 V1334-REF8 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 17 V1334-REF4 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 18 V1334-REF3 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 19 V1334-CYG FGS POS 1 F5ND 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 20 V1334-REF7 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 21 V1334-REF6 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 13849( 3) - 09-Jul-2014 15:06:24 - [ 5] Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 22 V1334-CYG FGS POS 1 F5ND 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 23 V1334-REF5 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 24 V1334-REF9 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 25 V1334-REF8 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 26 V1334-REF4 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 27 V1334-REF3 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 28 V1334-CYG FGS POS 1 F5ND 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 29 V1334-REF7 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 30 V1334-REF6 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 31 V1334-REF2 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 32 V1334-REF11 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 33 V1334-CYG FGS POS 1 F5ND 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 34 V1334-REF8 FGS POS 1 F583W 1 2 S (2 S) SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ V1334-CYG 1 FGS POS 1 F5ND none none none none 1 N/A V1334-REF2 2 FGS POS 1 F583W none none none none 1 N/A V1334-REF9 3 FGS POS 1 F583W none none none none 1 N/A V1334-REF8 4 FGS POS 1 F583W none none none none 1 N/A V1334-REF4 5 FGS POS 1 F583W none none none none 1 N/A V1334-REF3 6 FGS POS 1 F583W none none none none 1 N/A V1334-CYG 7 FGS POS 1 F5ND none none none none 1 N/A V1334-REF7 8 FGS POS 1 F583W none none none none 1 N/A V1334-REF6 9 FGS POS 1 F583W none none none none 1 N/A V1334-REF2 10 FGS POS 1 F583W none none none none 1 N/A V1334-CYG 11 FGS POS 1 F5ND none none none none 1 N/A V1334-REF2 12 FGS POS 1 F583W none none none none 1 N/A V1334-REF5 13 FGS POS 1 F583W none none none none 1 N/A V1334-REF11 14 FGS POS 1 F583W none none none none 1 N/A V1334-REF9 15 FGS POS 1 F583W none none none none 1 N/A 13849( 3) - 09-Jul-2014 15:06:24 - [ 6] 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 | ------------------------------------------------------------------------------------------------------------------------------------ V1334-REF8 16 FGS POS 1 F583W none none none none 1 N/A V1334-REF4 17 FGS POS 1 F583W none none none none 1 N/A V1334-REF3 18 FGS POS 1 F583W none none none none 1 N/A V1334-CYG 19 FGS POS 1 F5ND none none none none 1 N/A V1334-REF7 20 FGS POS 1 F583W none none none none 1 N/A V1334-REF6 21 FGS POS 1 F583W none none none none 1 N/A V1334-CYG 22 FGS POS 1 F5ND none none none none 1 N/A V1334-REF5 23 FGS POS 1 F583W none none none none 1 N/A V1334-REF9 24 FGS POS 1 F583W none none none none 1 N/A V1334-REF8 25 FGS POS 1 F583W none none none none 1 N/A V1334-REF4 26 FGS POS 1 F583W none none none none 1 N/A V1334-REF3 27 FGS POS 1 F583W none none none none 1 N/A V1334-CYG 28 FGS POS 1 F5ND none none none none 1 N/A V1334-REF7 29 FGS POS 1 F583W none none none none 1 N/A V1334-REF6 30 FGS POS 1 F583W none none none none 1 N/A V1334-REF2 31 FGS POS 1 F583W none none none none 1 N/A V1334-REF11 32 FGS POS 1 F583W none none none none 1 N/A V1334-CYG 33 FGS POS 1 F5ND none none none none 1 N/A V1334-REF8 34 FGS POS 1 F583W none none none none 1 N/A 13849( 3) - 09-Jul-2014 15:06:24 - [ 7] Visit: 02 Visit Requirements: BETWEEN 10-AUG-2015:00:00:00 AND 29-OCT-2015:00:00:00 On Hold Comments: Additional Comments: Our adopted UV spectral energy distribution is based on the IUE low dispersion, large aperture observations SWP41795 and LWP20452. In the FUV, the contribution of the Cepheid itself is negligible, and the spectrum is dominated by the late-B star companion, with a flux at 1400 angstroms of about 1e-11 ergs/cm2/s/A. There are also two other SWP low dispersion, large aperture spectra, SWP08319 and SWP19267, taken at different epochs, which show essentially the same flux, so any significant FUV flux variability can be ruled out. Inserting our adopted spectral energy distribution into the ETC for the E140H 1271 with the 0.2X0.09 aperture gives a predicted global count rate of about 12500 c/s (ETC ID STIS.sp.466167). 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 V1334-CYG STIS/CCD ACQ F25ND3 MIRROR 1 0.2 S (0.2 SEQ 1-5 NON-INT S) ------------------------------------------------------------------------------------------------------------------------------------ 2 V1334-CYG STIS/CCD ACQ/PEA 0.2X0.09 G230LB 2375 1 2.0 S (2 K S) ------------------------------------------------------------------------------------------------------------------------------------ 3 WAVE STIS/FUV ACCUM 0.2X0.09 E140H 1271 1 75 S (75 -MAMA S) ------------------------------------------------------------------------------------------------------------------------------------ 4 V1334-CYG STIS/FUV TIME-TA 0.2X0.09 E140H 1271 WAVECAL=NO, BUFFER-TIME=99 1 1800 S -MAMA G (1800 S) Comments: 1271 (STIS.sp.466167) predicts global rate of about 12, 500 ------------------------------------------------------------------------------------------------------------------------------------ 5 WAVE STIS/FUV ACCUM 0.2X0.09 E140H 1271 1 250 S (250 -MAMA 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 | ------------------------------------------------------------------------------------------------------------------------------------ V1334-CYG 1 STIS/CCD ACQ F25ND3 MIRROR none none none none 1 N/A V1334-CYG 2 STIS/CCD ACQ/PEA 0.2X0.09 G230LB 2375 none none none none 1 N/A K WAVE 3 STIS/FUV ACCUM 0.2X0.09 E140H 1271 none none none none 1 N/A -MAMA V1334-CYG 4 STIS/FUV TIME-TA 0.2X0.09 E140H 1271 none none none none 1 N/A -MAMA G WAVE 5 STIS/FUV ACCUM 0.2X0.09 E140H 1271 none none none none 1 N/A -MAMA 13849( 3) - 09-Jul-2014 15:06:24 - [ 8] Summary Form for Proposal 13849 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 0.2X0.09, 1, F25ND3 ------------------------------------------------------------------------------------------------------------------------------------ Configurations FGS, STIS/CCD, STIS/FUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, ACQ, ACQ/PEAK, POS, TIME-TAG ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BUFFER-TIME=99, WAVECAL=NO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BETWEEN 06-AUG-2015 AND 09-AUG-2015, BETWEEN 10-AUG-2015:00:00:00 AND 29-OCT-2015:00:00:00, ORIENT 187D TO 189 D, SAME POS AS 1, SEQ 1-34 NON-INT, SEQ 1-5 NON-INT ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements E140H, F583W, F5ND, G230LB, MIRROR ------------------------------------------------------------------------------------------------------------------------------------ Target Names V1334-CYG, V1334-REF11, V1334-REF2, V1334-REF3, V1334-REF4, V1334-REF5, V1334-REF6, V1334-REF7, V1334-REF8, V1334-REF9, WAVE ------------------------------------------------------------------------------------------------------------------------------------