8613( 3) - 01/24/00 14:33 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8613 Version: 3 Check-in Date: 24-Jan-2000 14:32:49 1.Proposal Title: Coordinated Observations of Stellar Flares on AD Leo ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 9 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Suzanne Hawley University of Washington CoI: Dr. William Abbett University of California N CoI: Dr. George Fisher University of California N CoI: Dr. Chris Johns-Krull University of California N ------------------------------------------------------------------------------------ 5. Abstract We will obtain high resolution HST/STIS spectra of the dMe star AD Leo during periods of quiescence and during flares to study the physics of atmospheric heating in flare stars. The HST observations will form an essential part of a large, coordinated observing campaign including FUSE, EUVE, and ground-based observations (both multicolor photometry and high resolution optical spectroscopy). The STIS spectra, in combination with data from the other satellites, will allow us to determine the structure (during quiescence) and evolution (during flares) of the temperature and density in the corona, transition region, and chromosphere. These data will provide strong empirical constraints on our current generation of flare evolution models. The uniquely high spectral resolution of the STIS data will also allow us to directly observe the dynamic effects of the chromospheric shocks that are predicted by the models. In addition, we will search for significant red-shifted emission in the hydrogen Lyman-Alpha line during the flare rise phase, which is a signature of an energetic proton beam. The existence and role of proton beams in both solar and stellar flares is currently a subject of considerable debate. ------------------------------------------------------------------------------------ 8613( 3) - 01/24/00 14:33 - [ 2] Observations Description ------------------------ We will observe AD Leo in Time-Tag mode with the STIS E140M grating coupled to the 0.2 X 0.2 arcsecond slit to provide the maximum throughput with high spectral resolution. Aside from standard telescope and instrument overheads, we will take a single Time-Tag exposure during each orbit on target. We extracted the GHRS spectrum obtained during a small flare on AD Leo (Bookbinder et al. (1992) - see Figure 1) and used the on-line STIS exposure time calculator to estimate the S/N in our proposed observations. During the peak of this flare, we expect a S/N of 10 in the C iv line for a 1 minute exposure. Large flares on AD Leo typically have line emission lasting an hour or more. This observing setup also provides velocity resolution of better than 20 km/s, more than a factor of 10 better than any previous UV observations of stellar flares spanning such a range of TR and chromospheric diagnostics. Due to HST/STIS limitations with regard to the SAA, we can only observe for 5-6 orbits contiguously. The FUSE and EUVE satellite data will be obtained over 3 days, so we are requesting 20 orbits (i.e. 4 visits of 5 contiguous orbits) which will provide coverage spread over the three day coordinated observing program. Real Time Justification ----------------------- This proposal is to coordinate HST/STIS observations with FUSE and EUVE. We originally submitted this proposal for Director's Discretionary Time because the FUSE and EUVE observations were awarded after the HST Cycle 8 deadline, and the observations will take place in the spring of 2000, before the nominal start of Cycle 9 observing (July 2000). The Director instructed us to apply through the regular Cycle 9 call for proposals with the note that a special exception will be made such that if this proposal is approved, STScI will make every effort to schedule the observations as part of the coordinated campaign. Our FUSE and EUVE time has been awarded during the period 10-13 March 2000 (UT), and we have now also been successful in obtaining ground-based observing time at McDonald Observatory and DAO during that period. We are requesting 20 orbits, which packed together in contiguous non-SAA passage orbits will provide approximately 3 days of coverage to overlap with the approved time on FUSE and EUVE. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 8613( 3) - 01/24/00 14:33 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 BD+20D2465 STAR, M V-IV, EMISSION RA=10H 19M 36.915S +/- 0.3", J2000 V = V = 9.43+/-0.1 LINE STAR, CORONA DEC=19D 52' 12.4" +/- 0.3", +10.8 B-V = 1.54+/-0.2 PLATE-ID=026A TYPE=M3V F-CONT(1600)=3.0+/-2.0e-15 F-LINE(1216)=4.5+/-1e-12 W-LINE(1216)=2.7+/-0.4 F-LINE(1549)=3.5+/-1.0e-13 W-LINE(1549)=1.0+/-0.2 Comments: All UV flux values for AD Leo come from IUE Final Archive low resolution spectra. To our knowledge, there are no high dispersion UV spectra of AD Leo with adequate signal-to-noise to estimate line widths. As a result, the Ly-alpha 1216 flux reported here contains some contribution from Geocoronal emission. To estimate line widths, we used IUE Final Archive high dispersion spectra of the active star HR 1099. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1982.96 -0.0355 -0.046 0.213 8613( 3) - 01/24/00 14:33 - [ 4] Visit: 01 Visit Priority: Visit Requirements: BETWEEN 10-Mar-2000:02:00:00.0 AND 10-Mar-2000:05:00:00.0 On Hold Comments: Additional Comments: We have requested the first visit during U.S. nighttime on 10 March 2000 (UT - in other words the night of 9/10 March 2000 civil time) using the BETWEEN requirement, and the remaining three visits during the next 3 days, using the SEQ WITHIN requirement. If possible we would like to have all four visits scheduled during U.S. nighttime, i.e. on the nights of 9/10, 10/11, 11/12 and 12/13 March. In UT this would be start times between 2-5h UT on 10, 11, 12 and 13 March. Thus, we have also used the BETWEEN requirement on visits 2, 3 and 4 to specify start times at the beginning of US nighttime. If this requirement is too restrictive for any of the visits, for example because of SAA passages affecting the MAMAs, then we are willing to drop it in order to have the visit be schedulable. The U.S. nighttime is preferable to obtain simultaneous observations with the other satellites and with ground based observatories, but U.S. daytime would still allow us to obt ain simultaneous observations with the other satellites and would be preferable to no observations at all. The scheduling of the FUSE and EUVE satellites is not yet complete, which might change the start requirements for the first and/or last visits. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 BD+20D2465 STIS/C ACQ F28X50O MIRROR ACQTYPE=POINT 1 2 S CD III ------------------------------------------------------------------------------------------------------------------------------------ 20 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2200 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 30 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 40 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 50 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 60 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 8613( 3) - 01/24/00 14:33 - [ 5] Visit: 02 Visit Priority: Visit Requirements: BETWEEN 11-Mar-2000:02:00:00.0 AND 11-Mar-2000:05:00:00.0 On Hold Comments: Additional Comments: See comment to visit 1 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 BD+20D2465 STIS/C ACQ F28X50O MIRROR ACQTYPE=POINT 1 2 S CD III ------------------------------------------------------------------------------------------------------------------------------------ 20 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2200 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 30 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 40 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 50 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 60 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 8613( 3) - 01/24/00 14:33 - [ 6] Visit: 03 Visit Priority: Visit Requirements: BETWEEN 12-Mar-2000:02:00:00.0 AND 12-Mar-2000:05:00:00.0 On Hold Comments: Additional Comments: See comment to visit 1 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 BD+20D2465 STIS/C ACQ F28X50O MIRROR ACQTYPE=POINT 1 2 S CD III ------------------------------------------------------------------------------------------------------------------------------------ 20 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2200 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 30 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 40 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 50 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 60 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 8613( 3) - 01/24/00 14:33 - [ 7] Visit: 04 Visit Priority: Visit Requirements: BETWEEN 13-Mar-2000:02:00:00.0 AND 13-Mar-2000:05:00:00.0 On Hold Comments: Additional Comments: See comment to visit 1 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 10 BD+20D2465 STIS/C ACQ F28X50O MIRROR ACQTYPE=POINT 1 2 S CD III ------------------------------------------------------------------------------------------------------------------------------------ 20 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2200 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 30 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 40 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 50 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 60 BD+20D2465 STIS/F TIME-TA 0.2X0.2 E140M 1425 BUFFER-TIME=550 1 2700 S UV-MAM G A ------------------------------------------------------------------------------------------------------------------------------------ 8613( 3) - 01/24/00 14:33 - [ 8] Summary Form for Proposal 8613 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures F28X50OIII 0.2X0.2 ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD STIS/FUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ TIME-TAG ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ACQTYPE=POINT BUFFER-TIME=550 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BETWEEN 10-Mar-2000 02 00 00.0 AND 10-Mar-2000 05 00 00.0 BETWEEN 11-Mar-2000 02 00 00.0 AND 11-Mar-2000 05 00 00.0 BETWEEN 12-Mar-2000 02 00 00.0 AND 12-Mar-2000 05 00 00.0 BETWEEN 13-Mar-2000 02 00 00.0 AND 13-Mar-2000 05 00 00.0 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR E140M ------------------------------------------------------------------------------------------------------------------------------------ Target Names BD+20D2465 ------------------------------------------------------------------------------------------------------------------------------------ Wavelengths 1425 ------------------------------------------------------------------------------------------------------------------------------------