Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 2485c Report Date: 09-May-96:17:09 Version: ********** Check-in Date: ********** 1.Proposal Title: SLEUTHING THE DYNAMO: CYCLE 1 OBSERVATIONS ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID STELLAR ASTROPHYSICS GO 2 Long Term yrs Sub Category EARLY EVOLUTION ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Dr. Thomas R. Ayres COLORADO, UNIVERSITY OF USA 303-492-4051 RESEARCH PROFESSOR ------------------------------------------------------------------------------------ 7. Abstract Innovative technologies of the 1990s will open new windows to the interior of the Sun and its hidden dynamics: the GONG project for helioseismology; rare-earth detectors for solar neutrinos; and SOLAR PROBE for high-order moments of the mass distribution. At the same time, newly-commissioned space observatories will provide unprecedented views of the vacuum-UV and X-ray emissions of stars in our Galactic neighborhood. These seemingly unrelated developments are in fact deeply connected. A central issue of solar-stellar physics is the nature and origin of magnetic activity: the profound link between the interior dynamics of a late-type star and the violent state of its outermost million-degree coronal layers. As solar physicists are unlocking the secrets of the hydromagnetic dynamo deep inside the Sun, we will apply one of the powerful new astronomical tools of the decade -- the HST -- to document the early evolution of the dynamo and its associated external gas -dynamic activity. In particular, we will obtain high-S/N FUV spectra of solar-type stars in young galactic clusters ranging in age from 1/10-th to 1/100-th that of the Sun. ------------------------------------------------------------------------------------ 8. Scientific Key Words: OPEN CLUSTER, DWARF, MS STAR, CHROMOSPHERE, CORONA ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 6.00 par: 0 10. Num targs pri: 5 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: HRS ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 2485c PI: Dr. Thomas R. Ayres Proposal Title: SLEUTHING THE DYNAMO: CYCLE 1 OBSERVATIONS ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Dr. Thomas R. Ayres COLORADO, UNIVERSITY OF USA Prof. Gibor S. Basri CALIFORNIA, UNIVERSITY OF, USA BERKELEY Dr. Theodore Simon HAWAII, UNIVERSITY OF USA Dr. John R. Stauffer CFA USA Dr. Robert A. Stern LOCKHEED PALO ALTO RESEARCH LABS USA Dr. Spiro K. Antiochos US NAVAL RESEARCH LABORATORY USA Dr. Jay A. Bookbinder CFA USA Dr. Alexander Brown COLORADO, UNIVERSITY OF USA Dr. George A. Doschek US NAVAL RESEARCH LABORATORY USA Dr. Jeffrey L. Linsky COLORADO, UNIVERSITY OF USA Prof. Lawrence W. Ramsey PENN STATE UNIVERSITY USA Prof. Frederick M. Walter NEW YORK, STATE UNIVERSITY OF USA (STONY BROOK) ------------------------------------------------------------------------------------ 2. Scientific Justification. 2. Scientific Justification ==> Not required for Phase II <== ------------------------------------------------------------------------------------ 3. Description of proposed observations. 3. Short Description of Proposed Observations We intend to record diagnostic- quality far-UV spectra of solar-type stars in young galactic clusters including the Hyades, the Pleiades, and ALPHA Persei. We selected five stars from each cluster which meet a number of strict criteria for membership, very likely are single, and which have reddening-corrected colors corresponding to G0-G3. Recording the critical spectral emissions in the far-UV -- from C III 1175, O V] 1218, and N V 1240 to C IV 1550 and He II 1640 -- requires two separate grating settings with the FOS: G130H & G190H. An additional brief exposure with G270H will record the bright Mg II 2800 h & k emissions at sufficient resolution to measure the integrated fluxes. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. 4. Need for HST We will investigate the high-excitation outer atmospheres of solar-type stars -- energized by magnetic activity -- as they age along their MS evolutionary tracks. On the Sun, co-spatiality between magnetic flux and high- excitation emissions is emphasized in the 100,000 K vacuum-UV resonance lines like C IV 1548 and N V 1238; whereas traditional ``chromospheric'' diagnostics accessible from the ground -- like Ca II and H-ALPHA -- tend to be contaminated to an uncertain degree by heating unrelated to magnetic activity, or suffer from uncertain modes of formation. Three stars of our sample -- HD28344, HD28992, and HZ1514 -- have been observed previously with IUE LWP-LO exposures to record the Mg II 2800 emission. There are no SWP-LO spectra of our program stars, and previous attempts to expose deep SWP-LOs of other (X-ray-selected) Hyads have produced only poor-quality spectral material. Page 3 ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. 5. Justification of Exposure Times We calculated FOS/BL G130H exposure times to achieve S/N = 35 at C IV 1548 in 30M. That ensures adequate S/N at C III] 1175 & N V 1238. For the Hyades (CYCLE-1 targets), we estimated f_1548 by scaling R_1548 (f_1548/f_bol) from measured values of R_2800 (Mg II) according to the power-law R_1548 = const R_2800^1.5. We will observe the 5 Hyads with the complete sequence of 3 FOS/BL gratings, with the same exposure time for each target to ensure uniformity. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. 6. a. Justification of special scheduling requests ==> none <== 6. b. Special calibration requirements ==> none <== ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. 7. Data Reduction and Analysis Calibration of the FOS spectra will be undertaken at the STSci. Two team members are HRS/GTOs, and we expect to benefit from their experience. Initially, the spectral traces will be measured using standard fitting routines available at Colorado through the IUE RDAF. Subsequently, emission-measure modelling, density-sensitive line-ratio tests, and correlations with other diagnostics (like ground- based Ca K fluxes or ROSAT X-ray detections) will be conducted by specific team members. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. 8. Special Comments ==> none <== ------------------------------------------------------------------------------------ 9. Description of previous HST work. 9. Previous HST observing Time ==> none <== ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). 10. Resources to be Supplied by Institution(s) Several domestic institutions are involved in our consortium. The resources and facilities that will be devoted to the project are extensive and varied. ------------------------------------------------------------------------------------ 11. Address Information Name: THOMAS R. AYRES Category: PI Institution: UNIVERSITY OF COLORADO Address: CAMPUS BOX 391 (CASA) City: BOULDER State: CO Zip Code: 80309 Country: USA Telephone: 303-492-4051 Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 2485c [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 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 HD25825 STAR; TYPE=G0 V; OPEN RA=4H 6M 15.96S +/- 1", 2000 1 V = +7.85 +/- 0.02, TYPE = G0 V CLUSTER DEC=+15D 41' 52.91" +/- 1", 1 B-V = +0.59 +/- 0.02 PLATE-ID=000O 3 F-LINE(2795) = 1 +/- 0.5 E-12 3 W-LINE(2795) = 1 +/- 0.2 4 F-LINE(1892) = 2 +/- 1 E-14 4 W-LINE(1892) = 0.4 +/- 0.1 5 F-LINE(1548) = 2 +/- 1 E-13 5 W-LINE(1548) = 0.3 +/- 0.1 Comments: FAR-UV SPECTRA OF SOLAR-TYPE STARS IN YOUNG GALACTIC CLUSTERS HYADES G0 V STAR Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1983.00 0.0092 +/- 0.0005 -0.0180 +/- 0.0090 0.0230 +/- 0.0010 ------------------------------------------------------------------------------------------------------------------------------------ 2 HD26767 STAR; TYPE=G2 V; OPEN RA=4H 14M 27.14S +/- 1", 2000 1 V = +8.06 +/- 0.02, TYPE = G2 V CLUSTER DEC=+12D 26' 7.25" +/- 1", 1 B-V = +0.64 +/- 0.02 PLATE-ID=01X0 3 F-LINE(2795) = 1 +/- 0.5 E-12 3 W-LINE(2795) = 1 +/- 0.2 4 F-LINE(1892) = 2 +/- 1 E-14 4 W-LINE(1892) = 0.4 +/- 0.1 5 F-LINE(1548) = 2 +/- 1 E-13 5 W-LINE(1548) = 0.3 +/- 0.1 Comments: FAR-UV SPECTRA OF SOLAR-TYPE STARS IN YOUNG GALACTIC CLUSTERS HYADES G2 V STAR Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1983.00 0.0072 +/- 0.0080 0.0030 +/- 0.0090 0.0230 +/- 0.0010 ------------------------------------------------------------------------------------------------------------------------------------ 3 HD27835 STAR; TYPE=G0 V; OPEN RA=4H 24M 12.695S +/- 1", 2000 1 V = +8.24 +/- 0.02, TYPE = G0 V CLUSTER DEC=+16D 22' 44.45" +/- 1", 1 B-V = +0.59 +/- 0.02 PLATE-ID=000P 3 F-LINE(2795) = 1 +/- 0.5 E-12 3 W-LINE(2795) = 1 +/- 0.2 4 F-LINE(1892) = 2 +/- 1 E-14 4 W-LINE(1892) = 0.4 +/- 0.1 5 F-LINE(1548) = 2 +/- 1 E-13 5 W-LINE(1548) = 0.3 +/- 0.1 Comments: FAR-UV SPECTROPHOTOMETRY OF SOLAR-TYPE STARS IN YOUNG GALACTIC CLUSTERS HYADES G0 V STAR Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1983.00 0.0061 +/- 0.0005 -0.0170 +/- 0.0090 0.0230 +/- 0.0010 ------------------------------------------------------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 2485c [ 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| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 4 HD28344 STAR; TYPE=G2 V; OPEN RA=4H 28M 48.155S +/- 1", 2000 1 V = +7.85 +/- 0.02, TYPE = G2 V CLUSTER DEC=+17D 17' 7.88" +/- 1", 1 B-V = +0.61 +/- 0.02 PLATE-ID=000P 3 F-LINE(2795) = 1 +/- 0.5 E-12 3 W-LINE(2795) = 1 +/- 0.2 4 F-LINE(1892) = 2 +/- 1 E-14 4 W-LINE(1892) = 0.4 +/- 0.1 5 F-LINE(1548) = 2 +/- 1 E-13 5 W-LINE(1548) = 0.3 +/- 0.1 Comments: FAR-UV SPECTRA OF SOLAR-TYPE STARS IN YOUNG GALACTIC CLUSTERS HYADES G2 V STAR Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1983.00 0.0070 +/- 0.0005 -0.0430 +/- 0.0090 0.0230 +/- 0.0010 ------------------------------------------------------------------------------------------------------------------------------------ 5 HD28992 STAR; TYPE=G1 V; OPEN RA=4H 34M 35.177S +/- 1", 2000 1 V = +7.94 +/- 0.02, TYPE = G1 V CLUSTER DEC=+15D 30' 17.56" +/- 1", 1 B-V = +0.63 +/- 0.02 PLATE-ID=002J 3 F-LINE(2795) = 1 +/- 0.5 E-12 3 W-LINE(2795) = 1 +/- 0.2 4 F-LINE(1892) = 2 +/- 1 E-14 4 W-LINE(1892) = 0.4 +/- 0.1 5 F-LINE(1548) = 2 +/- 1 E-13 5 W-LINE(1548) = 0.3 +/- 0.1 Comments: FAR-UV SPECTRA OF SOLAR-TYPE STARS IN YOUNG GALACTIC CLUSTERS HYADES G1 V STAR Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1983.00 0.0072 +/- 0.0005 -0.0400 +/- 0.0090 0.0230 +/- 0.0010 ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 2485c [ 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 DEFINE # FOS/BL ACQ/ 4.3 G270H TYPE=UP 1 1S 10 1 1 SPATIAL SCAN POASH PEAK ONBOARD ACQ FOR 1.100 SEQ 1.000-1.100 NO GAP GROUP 1-4 NO GAP CYCLE 1 / 1-4 ------------------------------------------------------------------------------------------------------------------------------------ 1.1 DEFINE # FOS/BL ACQ/ 1.0 G270H TYPE=UP 1 1S 10 1 1 SPATIAL SCAN POASH PEAK ONBOARD ACQ FOR 2- 4 ------------------------------------------------------------------------------------------------------------------------------------ 2 DEFINE # FOS/BL ACCUM 4.3 G270H 2700 1 50S 100 3 3 POASH 60S ------------------------------------------------------------------------------------------------------------------------------------ 3 DEFINE # FOS/BL ACCUM 4.3 G190H 1900 1 930S 20 4 2 POASH 30M ------------------------------------------------------------------------------------------------------------------------------------ 4 DEFINE # FOS/BL ACCUM 4.3 G130H 1300 1 1650S 35 5 1 POASH 30M ------------------------------------------------------------------------------------------------------------------------------------ 10 USE HD28344 POASH ------------------------------------------------------------------------------------------------------------------------------------ 11 USE HD28992 POASH ------------------------------------------------------------------------------------------------------------------------------------ 12 USE HD25825 POASH ------------------------------------------------------------------------------------------------------------------------------------ 13 USE HD26767 POASH ------------------------------------------------------------------------------------------------------------------------------------ 14 USE HD27835 POASH ------------------------------------------------------------------------------------------------------------------------------------ Scan Paramters Form Proposal ID: 2485c [ 7] ------------------------------------------------------------------------------------------------------------------------------------ Data ID: 1 Exposure Logsheet lines: 1.0 FGS Scan: DWELL Dwell Only: dwell points/line: 7 Seconds per dwell: 1.00 Scan width (arc-secs): 0.0000 Scan length (arc-secs): 4.3000 Angle between sides (degrees) 90.00 Number of lines: 1 Scan rate (arc-sec/sec): 0.0000 PA of first scan line (degrees) 0.000 Scan frame (CEL or S/C): S/C Length Offset (arc-sec): 2.1000 Width Offset (arc-sec): 0.0 ------------------------------------------------------------------------------------------------------------------------------------ Data ID: 2 Exposure Logsheet lines: 1.1 FGS Scan: DWELL Dwell Only: dwell points/line: 6 Seconds per dwell: 1.00 Scan width (arc-secs): 0.0000 Scan length (arc-secs): 4.3000 Angle between sides (degrees) 90.00 Number of lines: 1 Scan rate (arc-sec/sec): 0.0000 PA of first scan line (degrees) 90.000 Scan frame (CEL or S/C): S/C Length Offset (arc-sec): 2.1000 Width Offset (arc-sec): 0.0 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 2485c [ 8] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOS/BL ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/PEAK ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters TYPE ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 6.00 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category STELLAR ASTROPHYSICS ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category EARLY EVOLUTION ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements SPATIAL SCAN; ONBOARD ACQ FOR 1.100; SEQ 1.000-1.100 NO GAP; GROUP 1-4 NO GAP; CYCLE 1 / 1-4 ONBOARD ACQ FOR 2-4; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements G270H G190H G130H ------------------------------------------------------------------------------------------------------------------------------------ Target Names HD25825 HD26767 HD27835 HD28344 HD28992 ------------------------------------------------------------------------------------------------------------------------------------