16449( 3) - 07-Apr-2021 20:13:02 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 16449 Version: 3 Check-in Time: 07-Apr-2021 20:13:02 STScI Edit Number: 1 Title Testing the Lyman Alpha reconstructions vital for stellar and exoplanet astronomy ------------------------------------------------------------------------------------ Type Cycle GO 28 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. David John Wilson University of Texas at Austin Y CoI: Dr. Cynthia Suzanne Froning University of Texas at Austin N CoI: Dr. Allison Youngblood University of Colorado at Boulder N CoI: Dr. Brian Erland Wood Naval Research Laboratory N CoI: Dr. Jeremy J. Drake Smithsonian Institution Astrophysical N Observatory CoI: Prof. Kevin France University of Colorado at Boulder N CoI: Dr. Odette Fabiola Toloza The University of Warwick N Castillo CoI: Dr. Seth Redfield Wesleyan University N ------------------------------------------------------------------------------------ Abstract The HI Lyman alpha line dominates the ultraviolet emission of late type-stars. Observing Lyman alpha is vital for projects that wish to understand the chromospheric structure and behaviour of stars, as well as modeling the chemistry and characteristics of exoplanetary atmospheres. However, observing the Lyman alpha line is extremely difficult due to obscuration from the Interstellar Medium and telluric airglow. The numerous HST programs observing Lyman alpha lines rely on reconstruction models, which take what parts of the line can be observed and, via various recipes, infer the integrated flux and profile of the rest of the line. Testing the accuracy of such reconstruction techniques is difficult, requiring a system where the line can be observed in an obscured state and compared with the unobscured line. We have identified a system where this is possible: A close white dwarf-M dwarf binary where the high radial velocity change over the binary orbit moves the M dwarf Lyman alpha line in and out of obscuration. We propose to obtain phase-resolved STIS spectroscopy of the system to observe the Lyman alpha line at different levels of obscuration, which will then be tested against the maximum velocity, unobscured line. We describe our detailed planning of the experimental set up to calculate the small investment of HST time required and account for complexities such as flaring and coronal heating. This experiment will provide an unprecedented test of the Lyman alpha reconstructions that are at the heart of multiple past, present and (most likely) future HST programs. ------------------------------------------------------------------------------------ Observations Description ------------------------ The target is EG Uma, a post common envelope binary consisting of a white dwaf and an M dwarf. The four observations will obtain phase-resolved spectroscopy of the M dwarf Lyman alpha line emission line. The period is given by https://ui.adsabs.harvard.edu/abs/2000MNRAS.312...70B/abstract as HJD = 16449( 3) - 07-Apr-2021 20:13:02 - [ 2] 2449800:79131(58)+66765930(57), where the ephermeris is the blue-to-red crossing time of the radial velocity curve of the M dwarf. The four observations will observe the Lyman alpha line at four phases, measureing the line at different velocities. The ~16hr orbital period means that the velocity does not change by much during an HST orbit, increasing the scheduling flexability: Visit 01 should be obtained between phase 0.95 and 0.05. We expect to detect the wings of the Lyman alpha ine with S/N 10-20. Visit 02 should be obtained between phase 0.2 and 0.3. We expect to detect most of the Lyman alpha ine with S/N ~30. Visit 03 should be obtailed between phase 0.45 and 0.55. We expect to detect the wings of the Lyman alpha ine with S/N 10-20. Vist 04 should be obtained between 0.7 and 0.8, at maxmium radial veloctiy, This is the key observation of the proposal, when the Lyman alpha line will be clear of airglow and ISM absorption. We expect to detect the peak of the Lyman alpha ine with S/N 30-40. Note that Figure 2 of the proposal is out by phase = 0.5, the numbers here are correct. The order in which the observations are taken is unimportant. To increase flexability, Visits 01 and 03 may be obtained at the same phase (either 0.95-0.05 or 0.45-0.55) if scheduling them at different phases is impossible. Visit 02 can also be moved to phase 0.7-0.8 for a minor loss in scientific return. ------------------------------------------------------------------------------------ 16449( 3) - 07-Apr-2021 20:13:02 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 V-EG-UMA EXT-STAR, DA, M V-IV RA=12H15M43.9444S +/- 0.0205", J2000 V = 13.23 DEC=+52D30'59.24" +/- 0.0206" 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) 2015.5 -0.009911587420233209 -0.13201300000673655 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 16449( 3) - 07-Apr-2021 20:13:02 - [ 4] Visit: 01 Visit Requirements: SCHED 100%; BETWEEN 09-FEB-2021:00:00:00 AND 03-MAY-2021:00:00:00; BETWEEN 09-AUG-2021:00:00:00 AND 11-NOV-2021:00:00:00; Period 0.66765930 D AND ZERO-PHASE HJD2449800.79131 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 V-EG-UMA STIS/CCD ACQ F28X50LP MIRROR 1 1 S (1 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 V-EG-UMA STIS/CCD ACQ/PEA 52X0.1 MIRROR 1 1 S (1 S) K ------------------------------------------------------------------------------------------------------------------------------------ 3 V-EG-UMA STIS/FUV TIME-TA 52X0.1 G140M 1222 BUFFER-TIME=7930 1 1000 S PHASE 0.95 TO 0.05 -MAMA G see below (1358 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 | ------------------------------------------------------------------------------------------------------------------------------------ V-EG-UMA 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A V-EG-UMA 2 STIS/CCD ACQ/PEA 52X0.1 MIRROR none none none none 1 N/A K V-EG-UMA 3 STIS/FUV TIME-TA 52X0.1 G140M 1222 none none none none 1 1358.0 S -MAMA G 16449( 3) - 07-Apr-2021 20:13:02 - [ 5] Visit: 02 Visit Requirements: SCHED 100%; BETWEEN 09-FEB-2021:00:00:00 AND 03-MAY-2021:00:00:00; BETWEEN 09-AUG-2021:00:00:00 AND 11-NOV-2021:00:00:00; Period 0.66765930 D AND ZERO-PHASE HJD2449800.79131 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 V-EG-UMA STIS/CCD ACQ F28X50LP MIRROR 1 1 S (1 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 V-EG-UMA STIS/CCD ACQ/PEA 52X0.1 MIRROR 1 1 S (1 S) K ------------------------------------------------------------------------------------------------------------------------------------ 3 V-EG-UMA STIS/FUV TIME-TA 52X0.1 G140M 1222 BUFFER-TIME=7930 1 1400 S PHASE 0.2 TO 0.3 -MAMA G see below (1358 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 | ------------------------------------------------------------------------------------------------------------------------------------ V-EG-UMA 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A V-EG-UMA 2 STIS/CCD ACQ/PEA 52X0.1 MIRROR none none none none 1 N/A K V-EG-UMA 3 STIS/FUV TIME-TA 52X0.1 G140M 1222 none none none none 1 1358.0 S -MAMA G 16449( 3) - 07-Apr-2021 20:13:02 - [ 6] Visit: 03 Visit Requirements: SCHED 100%; BETWEEN 09-FEB-2021:00:00:00 AND 03-MAY-2021:00:00:00; BETWEEN 09-AUG-2021:00:00:00 AND 11-NOV-2021:00:00:00; Period 0.66765930 D AND ZERO-PHASE HJD2449800.79131 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 V-EG-UMA STIS/CCD ACQ F28X50LP MIRROR 1 1 S (1 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 V-EG-UMA STIS/CCD ACQ/PEA 52X0.1 MIRROR 1 1 S (1 S) K ------------------------------------------------------------------------------------------------------------------------------------ 3 V-EG-UMA STIS/FUV TIME-TA 52X0.1 G140M 1222 BUFFER-TIME=7930 1 1400 S PHASE 0.45 TO 0.55 -MAMA G see below (1358 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 | ------------------------------------------------------------------------------------------------------------------------------------ V-EG-UMA 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A V-EG-UMA 2 STIS/CCD ACQ/PEA 52X0.1 MIRROR none none none none 1 N/A K V-EG-UMA 3 STIS/FUV TIME-TA 52X0.1 G140M 1222 none none none none 1 1358.0 S -MAMA G 16449( 3) - 07-Apr-2021 20:13:02 - [ 7] Visit: 04 Visit Requirements: SCHED 100%; BETWEEN 09-FEB-2021:00:00:00 AND 03-MAY-2021:00:00:00; BETWEEN 09-AUG-2021:00:00:00 AND 11-NOV-2021:00:00:00; Period 0.66765930 D AND ZERO-PHASE HJD2449800.79131 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 V-EG-UMA STIS/CCD ACQ F28X50LP MIRROR 1 1 S (1 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 V-EG-UMA STIS/CCD ACQ/PEA 52X0.1 MIRROR 1 1 S (1 S) K ------------------------------------------------------------------------------------------------------------------------------------ 3 V-EG-UMA STIS/FUV TIME-TA 52X0.1 G140M 1222 BUFFER-TIME=7930 1 1400 S PHASE 0.7 TO 0.8 -MAMA G see below (1358 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 | ------------------------------------------------------------------------------------------------------------------------------------ V-EG-UMA 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A V-EG-UMA 2 STIS/CCD ACQ/PEA 52X0.1 MIRROR none none none none 1 N/A K V-EG-UMA 3 STIS/FUV TIME-TA 52X0.1 G140M 1222 none none none none 1 1358.0 S -MAMA G 16449( 3) - 07-Apr-2021 20:13:02 - [ 8] Visit: 53 Visit Requirements: SCHED 100%; BETWEEN 09-FEB-2021:00:00:00 AND 03-MAY-2021:00:00:00; BETWEEN 09-AUG-2021:00:00:00 AND 11-NOV-2021:00:00:00; Period 0.66765930 D AND ZERO-PHASE HJD2449800.79131 On Hold Comments: Additional Comments: Repeat of Visit 03 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 V-EG-UMA STIS/CCD ACQ F28X50LP MIRROR 1 1 S (1 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 V-EG-UMA STIS/CCD ACQ/PEA 52X0.1 MIRROR 1 1 S (1 S) K ------------------------------------------------------------------------------------------------------------------------------------ 3 V-EG-UMA STIS/FUV TIME-TA 52X0.1 G140M 1222 BUFFER-TIME=7930 1 1400 S PHASE 0.45 TO 0.55 -MAMA G see below (1358 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 | ------------------------------------------------------------------------------------------------------------------------------------ V-EG-UMA 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A V-EG-UMA 2 STIS/CCD ACQ/PEA 52X0.1 MIRROR none none none none 1 N/A K V-EG-UMA 3 STIS/FUV TIME-TA 52X0.1 G140M 1222 none none none none 1 1358.0 S -MAMA G 16449( 3) - 07-Apr-2021 20:13:02 - [ 9] Summary Form for Proposal 16449 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 52X0.1, F28X50LP ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD, STIS/FUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ, ACQ/PEAK, TIME-TAG ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BUFFER-TIME=7930 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BETWEEN 09-AUG-2021:00:00:00 AND 11-NOV-2021:00:00:00, BETWEEN 09-FEB-2021:00:00:00 AND 03-MAY-2021:00:00:00, PHASE 0.2 TO 0.3, PHASE 0.45 TO 0.55, PHASE 0.7 TO 0.8, PHASE 0.95 TO 0.05, Period 0.66765930 D AND ZERO-PHASE HJD2449800.79131, SCHED 100% ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements G140M, MIRROR ------------------------------------------------------------------------------------------------------------------------------------ Target Names V-EG-UMA ------------------------------------------------------------------------------------------------------------------------------------