Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 5306 Report Date: 18-Jul-95:17:07 Version: ********** Check-in Date: ********** 1.Proposal Title: MEASUREMENTS OF PROTON BEAMS IN STELLAR FLARES : CYCLE4 MEDIUM ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID COOL STARS GO Sub Category ACTIVE STARS ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Bruce E Woodgate NASA GODDARD/LASP USA (301) 286-5401 ------------------------------------------------------------------------------------ 7. Abstract We propose to observe the H Lyman Alpha profile of the flare star YZ CMI using the GHRS in the rapid readout mode to search for evidence of proton beams in stellar flares. Following our successful detection of a proton beam on the flare star AU Mic during cycle 1 we now wish to determine how often this phenomenon occurs, whether proton beams are seen on cooler stars, what is the time history and emission profile of the beam and whether the proton beam is energetically dominant during the impulsive phase. ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 9.49 par: 0 10. Num targs pri: 1 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: HRS ------------------------------------------------------------------------------------ 12. Special sched req: Time Critical obs. ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 5306 PI: Bruce E Woodgate Proposal Title: MEASUREMENTS OF PROTON BEAMS IN STELLAR FLARES : CYCLE4 MEDIUM ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Bruce Woodgate 2866 USA Kenneth Carpenter 2866 USA Richard Robinson 1780 USA Jeffrey Brosius 3480 USA Gordon Holman 2866 USA Jeffrey Linsky 1764 USA Anthony Danks 3480 USA Mukul Kundu 2620 USA ------------------------------------------------------------------------------------ 3. Description of proposed observations. We will use the GHRS with the G160M grating and the rapid readout mode to observe the Lyman alpha wavelength region of the active flare star YZ CMi with a time resolution of 0.4 seconds. The time interval was chosen as the smallest time consistent with continuous data storage on the science tape recorder. The observations will cover the wavelength range from 1203 to 1240 A and have a spectral resolution of approximately 10,000. If the low resolution G140L mode becomes available after the servicing mission, then we plan to request a change to observe with this grating and the SSA. The lower resolution data will allow a spectra coverage from 1150 to 1435 Angstroms, which covers a wide range of strong diagnostic lines such as C III, C II, Si IV, N V, O V, Fe XII, Fe XXI, CI and OI. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. Theory predicts that downstreaming non-thermal protons accelerated during the stellar flare will charge exchange with ambient hydrogen and become excited, downstreaming hydrogen atoms. These then emit red-shifted radiation into the wings of the various hydrogen lines. While a signature of proton beams should appear in the lines of the Balmer series, it will be MUCH more detectable in the wing of the Lyman alpha line because (a) the majority of the photons are emitted at Lyman alpha and (b) the quiescent stellar background is more than 8 orders of magnitude larger at the Balmer line wavelengths than at Lyman alpha, so a faint signal is more easily detected. Furthermore, as shown by our earlier successful detection of proton beams, the events may last for only a matter of seconds, requiring rapid time sequences. The GHRS aboard the HST is the only instrument currently available which allows high time resolution at the Lyman alpha wavelengths. Page 3 ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. We request scheduling of the HST obsrvations to coordinate with observations of the star at other wavelengths. Many of the goals of this project require only the HST observations. However, one major objective of the program is to determine whether the proton beams are the energetically dominant transport mechanism. To answer this question it is necessary to determine the total energy within the flare by observing at several wavelength regions, particularly in the optical, EUV and X-rays. For this reason we will be applying for coordinated observing time from ROSAT and EUVE and a variety of groundbased optical and radio observatories. In particular, we hope to obtain moderate resolution spectroscopy of the flares at high time resolution by using the new GSFC MAMA photon counting detector in a time tagged mode, where the position and time of each photon is stored on Exabyte tape for later analysis. Mounted on a large telescope such as the 3.9m Anglo-Australian Telescope or the McDonald 2.6m, the MAMA will allow us to obtain spectra with a time resolution which is limited only by the counting statistics. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. NONE ------------------------------------------------------------------------------------ 8. Additional comments or special requests. NONE ------------------------------------------------------------------------------------ 9. Description of previous HST work. Flare related GO and GTO observations: GO 2321 - Search for proton acceleration in flare stars - AU Mic 4214 - Rerun of part of 2321 (cycle 2) GTO 1158 - Coronal Flares Carpenter, Maran and Linsky have HST GTO programs which are not devoted to stellar flares. Limited space prevents us from listing these. High time resolution observations of the Lyman alpha line on the flare star AU Mic (GO 2321/4214) showed evidence for a significant increase in the red wing of the line during the peak of a flare event. There was no corresponding increase in the blue wing. This effect was first predicted by Orrall and Zirker in 1976 and results from the presence of a proton beam accelerated during the impulsive phase of the flare and streaming down through the atmosphere. The protons charge exchange with the ambient hydrogen atoms and then emit red-shifted Lyman alpha photons up to 10 A from line center. Preliminary calculations have shown that the detected beam may be responsible for transporting a significant amount of the flare energy. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). Software developed by the GHRS IDT and the proposers will be used in the reduction and analysis of these observations. A VAX cluster is available for data reduction and analysis at GSFC. ------------------------------------------------------------------------------------ 11. Address Information Name: BRUCE E WOODGATE Category: PI Institution: 2866 Address: CODE 681 GODDARD SPACE FLIGHT CENTER City: GREENBELT State: MD Zip Code: 20771 Country: USA Telephone: (301) 286-5401 Telex (or e-mail): CHAMP::WOODGATE ------------------------------------------------------------------------------------ Page 4 Name: RICHARD D ROBINSON Category: CON Institution: 1780 Address: CODE 681/CSC GODDARD SPACE FLIGHT CENTER City: GREENBELT State: MD Zip Code: 20771 Country: USA Telephone: (301) 286-4530 Telex (or e-mail): HRS::HRSROBINSON ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 5306 [ 5] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial |Acqui|FLX| Flux data No | Name | Description | Position |Eqnx | Vel. |Prblm|REF| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 1 YZ-CMI A, RA=07H 44M 40.11S +/- 1", 2000 V=18 1 V=11.2+/-1, TYPE=DM4.5E, 141,146, DEC=+03D 33' 08.25" +/- 1" Comments: FLARE STAR Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) J 2000.00 -0.0260 +/- 0.0000 -0.4700 +/- 0.0000 0.1650 +/- 0.0080 ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 5306 [ 6] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 YZ-CMI HRS ACQ 2.0 MIRROR-N2 LOCATE=YES 1 25.0S 1 1 CYCLE 4 / 1.0-13.0 BRIGHT=RETURN AT 21-DEC- SEARCH-SIZE=5 94:14:00:00 +/- 11H ONBOARD ACQ FOR 3.0 SEQ 1-13 Comments: STEP-TIME=1.0S , EXPECT 500 COUNTS IN STEP TIME ------------------------------------------------------------------------------------------------------------------------------------ 3 YZ-CMI HRS RAPID 2.0 G140L 1295 SAMPLE-TIME=0.4 1 41M 1 Comments: ONE TIME SEQUENCE PER ORBIT ------------------------------------------------------------------------------------------------------------------------------------ 4 YZ-CMI HRS RAPID 2.0 G140L 1295 SAMPLE-TIME=0.4 1 41M 1 ------------------------------------------------------------------------------------------------------------------------------------ 5 YZ-CMI HRS RAPID 2.0 G140L 1295 SAMPLE-TIME=0.4 1 41M 1 ------------------------------------------------------------------------------------------------------------------------------------ 6 YZ-CMI HRS RAPID 2.0 G140L 1295 SAMPLE-TIME=0.4 1 41M 1 ------------------------------------------------------------------------------------------------------------------------------------ 7 YZ-CMI HRS RAPID 2.0 G140L 1295 SAMPLE-TIME=0.4 1 41M 1 ------------------------------------------------------------------------------------------------------------------------------------ 8 YZ-CMI HRS RAPID 2.0 G140L 1295 SAMPLE-TIME=0.4 1 41M 1 ------------------------------------------------------------------------------------------------------------------------------------ 9 YZ-CMI HRS RAPID 2.0 G140L 1295 SAMPLE-TIME=0.4 1 41M 1 ------------------------------------------------------------------------------------------------------------------------------------ 10 YZ-CMI HRS RAPID 2.0 G140L 1295 SAMPLE-TIME=0.4 1 41M 1 ------------------------------------------------------------------------------------------------------------------------------------ 11 YZ-CMI HRS RAPID 2.0 G140L 1295 SAMPLE-TIME=0.4 1 40M 1 ------------------------------------------------------------------------------------------------------------------------------------ 12 YZ-CMI HRS RAPID 2.0 G140L 1295 SAMPLE-TIME=0.4 1 35M 1 ------------------------------------------------------------------------------------------------------------------------------------ 13 YZ-CMI HRS RAPID 2.0 G140L 1295 SAMPLE-TIME=0.4 1 29M 1 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 5306 [ 7] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HRS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ RAPID ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters LOCATE=YES BRIGHT=RETURN SEARCH-SIZE=5 SAMPLE-TIME=0.4 ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 9.49 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category COOL STARS ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category ACTIVE STARS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements CYCLE 4 / 1.0-13.0 ; AT 21-DEC-94 14 00 00 +/- 11H ; ONBOARD ACQ FOR 3.0 ; SEQ 1-13 ; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR-N2 G140L ------------------------------------------------------------------------------------------------------------------------------------ Target Names YZ-CMI ------------------------------------------------------------------------------------------------------------------------------------