8546( 7) - 08/20/99 07:06 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8546 Version: 7 Check-in Date: 20-Aug-1999 07:06:16 1.Proposal Title: The First Comprehensive High Spectral Resolution Study of Stellar Coronae: The 1999 Chandra, HST, EUVE, SAX and VLA Capella Campaign ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO/DD 8 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Jeremy Drake Harvard-Smithsonian Center for Astrophysics CoI: Nancy S. Brickhouse Smithsonian Astrophysical Observatory N CoI: Vinay Kashyap Smithsonian Astrophysical Observatory N CoI: Gerald Kriss STScI N CoI: Andrea Dupree Smithsonian Astrophyiscal Observatory N ------------------------------------------------------------------------------------ 5. Abstract We are requesting Director's discretionary time for obtaining HST STIS UV observations of the brightest X-ray emitting stellar corona in the sky, that of Capella, simultaneously with a unique campaign of very deep Chandra X-ray Observatory spectroscopic observations. Simultaneous observations with EUVE and the VLA have already been granted; a simultaneous observation with SAX is pending final approval. If STIS observations are approved, this campaign should provide the first detailed temperature and density diagnostics for stellar coronal plasma over the full range of temperatures 2e4 K - 8e7 K. STIS observations are essential for deconvolving the contributions of the two Capella binary components to the observed emission, and for probing the physics of transition region plasma. ------------------------------------------------------------------------------------ 8546( 7) - 08/20/99 07:06 - [ 2] Observations Description ------------------------ We propose to use STIS E140M for the Capella observations. We base exposure times on scaling the GHRS observation such that we obtain sufficient S/N in Fe XXI 1354 A to resolve the two coronae. Higher fluxes in transition region lines required for temperature, density and velocity studies will assure sufficient S/N in these lines to achieve the science goals. Using the 0.2X0.06 aperture to eliminate scattering wings and achieve the best spectral purity requires a 5400 s exposure with STIS/FUV-MAMA and E140M to obtain a S/N of > 20 per resolution element in the continuum, comparable in quality to the archival GHRS data. Our observation can be achieved in 3 orbits as follows: first with STIS/CCD acquisition and then STIS/FUV-MAMA exposures lasting 2005, 3054, 3054 s. At a DEC of 45 deg, Capella has a visibility of 55 minutes near the beginning of September. Orbit 1: 6m for GS Acq, 5m for STIS/CCD Acq, 7m for ACQ/PEAK, 2005s FUV-MAMA E140M, 0.2X0.06, 1425 A Orbit 2: 5m for GS ReAcq, 3054s FUV-MAMA E140M, 0.2X0.06, 1425 A Orbit 3: 5m for GS ReAcq, 3054s FUV-MAMA E140M, 0.2X0.06, 1425 A Real Time Justification ----------------------- Observations need to be simultaneous, or very near simultaneous, with Chandra spectrograph observations. Chandra observations are currently scheduled between 25 August and 3 September. While the Chandra schedule is expected to stabilize shortly, dates are currently likely to change due to uncertainties of the initial calibration phase. Calibration Justification ------------------------- Additional Comments ------------------- NONE. ------------------------------------------------------------------------------------ Data Distribution Paper Products: YES Media: DAT Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 8546( 7) - 08/20/99 07:06 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 CAPELLA STAR, G III-I, STAR, RA=05H 16M 41.359S +/- 0.05S, J2000 V = 0.10+/-0.11 CORONA DEC=45D 59' 52.768" +/- 0.1" B-V = 0.795 F(1215)=3.3+/-0.5e-10 F(1393)=1.5+/-0.3e-11 F(1548)=2.7+/-0.5e-11 TYPE=G8III+G1III Comments: Positions & Proper Motions from Hipparcos Catalogue via SIMBAD and http://www- gsss.stsci.edu/support/phase2.html (NOTE: calculated to EPOCH 2000); UV fluxes from recent high-res GHRS spectra (Tom Ayres, private communication). Predicted count rate for the brightest line is approx 13 ct/s and the next brightest line is 5 times fainter. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) J2000 0.005 0.472 0.0773 8546( 7) - 08/20/99 07:06 - [ 4] Visit: 01 Visit Priority: Visit Requirements: SCHED 30% BETWEEN 12-Sep-1999:16:00:00.0 AND 13-Sep-1999:02:00:00.0 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 CAPELLA STIS/C ACQ F25ND5 MIRROR 1 0.1 S CD Comments: ETC output (ID 19517): assuming G5I model spectrum, S/N=157 with brightest pixel at 1.52e4 e-, and total counts of 2.53e4 e-. ------------------------------------------------------------------------------------------------------------------------------------ 2 CAPELLA STIS/C ACQ/PEA 0.2X0.0 G430M 3936 1 0.2 S CD K 6 Comments: ETC output (ID 19453): assuming G5I model spectrum, S/N = 154 at 3936 AA for 0.2 s. Brightest pixel has 2.79e+04 e- at 4032 AA, and total counts over detector is 3.77e7 ------------------------------------------------------------------------------------------------------------------------------------ 3 CAPELLA STIS/F ACCUM 0.2X0.0 E140M 1425 BINAXIS1=NO,BINAXIS2=NO 1 2005 S UV-MAM 6 A Comments: Peak count rate from HI Lyman alpha is about 13 ct/s and is below MAMA bright limit. C IV 1548 will be detected at S/N > 100 over the duration of the observation. ------------------------------------------------------------------------------------------------------------------------------------ 4 CAPELLA STIS/F ACCUM 0.2X0.0 E140M 1425 BINAXIS1=NO,BINAXIS2=NO 2 3054 S UV-MAM 6 A Comments: Peak count rate from HI Lyman alpha is about 13 ct/s and is below MAMA bright limit. C IV 1548 will be detected at S/N > 100 over the duration of the observation. ------------------------------------------------------------------------------------------------------------------------------------ 8546( 7) - 08/20/99 07:06 - [ 5] Summary Form for Proposal 8546 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures F25ND5 0.2X0.06 ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD STIS/FUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACQ/PEAK ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BINAXIS1=NO BINAXIS2=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO/DD ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements SCHED 30% BETWEEN 12-Sep-1999 16 00 00.0 AND 13-Sep-1999 02 00 00.0 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G430M E140M ------------------------------------------------------------------------------------------------------------------------------------ Target Names CAPELLA ------------------------------------------------------------------------------------------------------------------------------------ Wavelengths 3936 1425 ------------------------------------------------------------------------------------------------------------------------------------