16392( 2) - 17-Sep-2020 15:34:04 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 16392 Version: 2 Check-in Time: 17-Sep-2020 15:34:04 STScI Edit Number: 0 Title X-rays from a Unique Spun-up Post Mass Transfer Main Sequence Carbon Star ------------------------------------------------------------------------------------ Type Cycle GO 28 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Paul J. Green Smithsonian Institution Astrophysical Y Observatory CoI: Mr. Benjamin R Roulston Boston University Y CoI: Dr. Rodolfo Montez Jr. Smithsonian Institution Astrophysical N Observatory CoI: Dr. Adam Frank University of Rochester N CoI: Prof. Michael Eracleous The Pennsylvania State University N CoI: Dr. Jeremy J. Drake Smithsonian Institution Astrophysical N Observatory CoI: Prof. Scott F. Anderson University of Washington N ------------------------------------------------------------------------------------ Abstract Carbon stars (C>O) were long assumed to all be giants, because only AGB stars dredge up significant carbon into their atmospheres. We now know that dwarf carbon (dC) stars are actually far more common than C giants. The dCs have accreted C-rich envelope material from an AGB companion, eventually yielding a white dwarf and a dC that has gained both significant mass and angular momentum. We propose a Chandra study of the nearest known typical dC, J0435+3401, to investigate its extreme X-ray spectral properties and variability, while using HST to constrain the cooling age of its white dwarf companion. Since dCs are the likely progenitors of CH, BaII and CEMP stars, and probably also interacting binaries like CVs, novae, or SN Ia, our results will have wide-ranging implications. ------------------------------------------------------------------------------------ Observations Description ------------------------ We plan observations of an interesting dwarf carbon (dC) star, utilizing both the ACS-SBC and WFC3-UVIS detectors. This will allow us to obtain stronger UV constraints than allowed by the weak GALEX NUV detection. The dC must have (from an evolutionary perspective) a WD component. Since no WD features are evident in the optical spectrum the WD must be relatively cool, implying Gyr since its AGB phase. We seek to detect and constrain its age using these NUV and FUV HST observations. For all ETC calculations we assume a 7, 000K blackbody normalized to the GALEX NUV magnitude, with E(B-V) =0.606. For the FUV observations, we use both the [F140LP] and [F165LP] filters in order to account for the red leak of the SBC as recommneded. We fit both observations into 1 orbit and the ACS ETC estimates a S/N~7 for both filter obeservations. 16392( 2) - 17-Sep-2020 15:34:04 - [ 2] THe WFC3 ETC predcits S/N=100 in the NUV with UVIS+[F225W] in 2384s. For both the SBC and UVIS observations we utilize a BOX dither. For the UVIS observations we include a post-FLASH of 11e to aid with CTE issues as recommended. The SBC observation passes the BOT using the GALEX catalog with all SAFE objects. The UVIS observations pass saturation checks with the BOT and GSC2. ------------------------------------------------------------------------------------ 16392( 2) - 17-Sep-2020 15:34:04 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 J043526.14+3 STAR, CARBON STAR RA=04H35M26.3050S +/- J2000 V = V = 14.48 +/- 0.2 B=15.2, R=13.5, 40136.48 0.0000374", DEC=+34D01'35.58" 77.43 G=13.7165, NUV=22.08, E(B-V)=0.606, +/- 0.0000237" dC+DA? Reference Frame: ICRS Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2015.5 0.012072869891524684 -0.069262 0.0078080 ------------------------------------------------------------------------------------------------------------------------------------ 16392( 2) - 17-Sep-2020 15:34:04 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type ACS-SBC-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.179 Line_Spacing 0.116 Coordinate_Frame POS-TARG Pattern_Orient 20.02 Angle_Between_Sides 63.65 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.173 Line_Spacing 0.112 Coordinate_Frame POS-TARG Pattern_Orient 23.884 Angle_Between_Sides 81.785 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 16392( 2) - 17-Sep-2020 15:34:04 - [ 5] Visit: 01 Visit Requirements: 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 J043526.14+ WFC3/UVI ACCUM UVIS2 F225W FLASH=11.0 1 2396 S PATTERN 2 1 340136.48 S see below (2384 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J043526.14+ ACS/SBC ACCUM SBC F140LP 1 2593 S PATTERN 1 2-3 340136.48 see below (1084 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 J043526.14+ ACS/SBC ACCUM SBC F165LP 1 1215 S 340136.48 see below (1091 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 | ------------------------------------------------------------------------------------------------------------------------------------ J043526.14+340136.4 1 WFC3/UVI ACCUM UVIS2 F225W 1 none none none 1 619.0 S 8 S J043526.14+340136.4 1 WFC3/UVI ACCUM UVIS2 F225W 2 none none none 1 619.0 S 8 S J043526.14+340136.4 1 WFC3/UVI ACCUM UVIS2 F225W 3 none none none 1 619.0 S 8 S J043526.14+340136.4 1 WFC3/UVI ACCUM UVIS2 F225W 4 none none none 1 527.0 S 8 S J043526.14+340136.4 2 ACS/SBC ACCUM SBC F140LP 1 none none none 2 271.0 S 8 J043526.14+340136.4 2 ACS/SBC ACCUM SBC F140LP 2 none none none 2 271.0 S 8 J043526.14+340136.4 2 ACS/SBC ACCUM SBC F140LP 3 none none none 2 271.0 S 8 J043526.14+340136.4 2 ACS/SBC ACCUM SBC F140LP 4 none none none 2 271.0 S 8 J043526.14+340136.4 3 ACS/SBC ACCUM SBC F165LP 1 none none none 2 275.0 S 8 J043526.14+340136.4 3 ACS/SBC ACCUM SBC F165LP 2 none none none 2 273.0 S 8 J043526.14+340136.4 3 ACS/SBC ACCUM SBC F165LP 3 none none none 2 271.0 S 8 J043526.14+340136.4 3 ACS/SBC ACCUM SBC F165LP 4 none none none 2 272.0 S 8 16392( 2) - 17-Sep-2020 15:34:04 - [ 6] Summary Form for Proposal 16392 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures SBC, UVIS2 ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/SBC, WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters FLASH=11.0 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 2-3, PATTERN 2 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F140LP, F165LP, F225W ------------------------------------------------------------------------------------------------------------------------------------ Target Names J043526.14+340136.48 ------------------------------------------------------------------------------------------------------------------------------------