Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 5738 Report Date: 18-Jul-95:17:55 Version: ********** Check-in Date: ********** 1.Proposal Title: THE STELLAR CONTENT OF WOLF-RAYET GALAXIES(FOS SPECTRA) ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID STELLAR POPULATIONS GO/CAR 4122 Sub Category YOUNG FIELD STARS ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Dr. Peter S. Conti JILA USA (303) 492-8497 ASTRONOMER ------------------------------------------------------------------------------------ 7. Abstract We propose to observe a comprehensive sample of Wolf-Rayet (W-R) galaxies --- starburst galaxies in which broad 4686 He II emission of stellar origin has been detected. These galaxies generally contain far more W-R stars than the Milky Way, M31, and other normal galaxies. The ultraviolet FOC images and FOS spectra will be combined with optical and infrared data as part of a large effort to perform a broad, systematic analysis of the properties of W-R galaxies. The UV data obtained with HST will provide crucial constraints on the hot star (O and W-R) populations, and will lead to a better understanding of the physical conditions, initial mass functions, and starburst parameters of these galaxies. The overall continuum will be analyzed within the framework of evolutionary and spectral synthesis models that we are developing. Quantitative spectroscopy of UV resonance lines will allow us to study the hot star populations in detail, and to directly measure the number of OB stars within these galaxies. Our main goal is to determine which physical properties of W-R galaxies (e.g., IMF slope, chemical composition, age, strength and duration of the starburst) have led to the production of large numbers of W-R stars. The results of this study will have important implications for our understanding of W-R galaxies,and also of starburst and emission-line galaxies in general. ------------------------------------------------------------------------------------ 8. Scientific Key Words: LBV'S, WOLF-RAYET STARS, STARBURSTS ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 12.4 par: 0 10. Num targs pri: 18 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: FOS ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 5738 PI: Dr. Peter S. Conti Proposal Title: THE STELLAR CONTENT OF WOLF-RAYET GALAXIES(FOS SPECTRA) ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Pi Peter S. Conti UNIVERSITY OF COLORADO USA Alexei V. Filippenko UNIVERSITY OF CALIFORNIA, USA BERKELEY Claus Leitherer SPACE TELESCOPE SCIENCE USA X INSTITUTE Carmelle Robert SPACE TELESCOPE SCIENCE USA INSTITUTE Wallace L. Sargent CALIFORNIA INSTITUTE OF USA TECHNOLOGY William D. Vacca UNIVERSITY OF CALIFORNIA, USA BERKELEY ------------------------------------------------------------------------------------ 3. Description of proposed observations. We would like to obtain FOS spectra of the brightest knots of some W-R galaxies. The objects were selected on the basis of the FOC data from another proposal; There may be more than one knot per galaxy. The scientific goal can be best achieved with the FOS and gratings G130H and G190H. We intend to use the blue- side detector for both gratings. A peak-up technique is used for the TA. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. It is the combination of the superior resolution (IUE: 6A; FOS: 3A for a knot of 2-3") and vastly better S/N (IUE: typically 10; FOS: 35 for our proposed observations) of HST data which provide a dramatic improvement. STRONG lines (like C IV) can be modeled quantitatively with HST, and WEAKER lines (like N IV 1718, which is an important signature of hot EVOLVED stars) can only be detected with HST, in contrast to IUE. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. No special calibrations are requested. According to the FOC instrument scientist, PSF's will be provided by STScI. ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. The general management of the observations (including the ground observations) and the data reduction and interpretation will be coordinated by Peter Conti. FOS deconvolution will be carried out by Claus Leitherer. P. Conti is also in charge of the pre-analysis of the HST observations (line identification, interstellar extinction...). Other observations from the ground are to be acquired, reduced and analysed by Alex Filippenko, Wal Sargent and Bill Vacca. The population synthesis models will be done at STScI by Carmelle Robert and Claus Leitherer. All co-Is will be intimately involved with data analysis and interpretation. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. The HST observations are supported by ground-based observations. There is no need for simultaneous observations. ------------------------------------------------------------------------------------ 11. Address Information Page 3 Name: PETER S CONTI Category: PI Institution: JILA/UNIV. OF COLORADO Address: CAMPUS BOX 440 City: BOULDER State: CO Zip Code: 80309 Country: USA Telephone: (303) 492-8497 Telex (or e-mail): 755842 JILA ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 5738 [ 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| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 10 NGC1741- E,318,928 RA=5H 01M 37.73S +/- 0.05S, 2000 EXT OFFSET DEC=-4D 15' 28.73" +/-0.5" ------------------------------------------------------------------------------------------------------------------------------------ 20 NGC1741B E,318,928 RA=5H 01M 37.70S +/- 0.05S, 2000 EXT DEC=-4D 15' 32.55" +/-0.5" ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 5738 [ 5] ------------------------------------------------------------------------------------------------------------------------------------ 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 ------------------------------------------------------------------------------------------------------------------------------------ 100 NGC1741- HRS ACQ 2.0 MIRROR-N2 SEARCH-SIZE=5 1 250S 1 CYCLE 4 OFFSET BRIGHT=RETURN ONBOARD ACQ FOR 101 SEQ 100-204 NO GAP Comments: STEP-TIME=10S ------------------------------------------------------------------------------------------------------------------------------------ 101 WAVE HRS ACCUM SC2 G140L 1320 1 60S 1 CYCLE 4 CALIB FOR 102 ------------------------------------------------------------------------------------------------------------------------------------ 102 NGC1741- HRS ACCUM 2.0 G140L 1320 1 6100S 1 CYCLE 4 OFFSET ------------------------------------------------------------------------------------------------------------------------------------ 103 WAVE HRS ACCUM SC2 G140L 1600 1 60S 1 CYCLE 4 CALIB FOR 104 ------------------------------------------------------------------------------------------------------------------------------------ 104 NGC1741- HRS ACCUM 2.0 G140L 1600 1 12200S 1 CYCLE 4 OFFSET ------------------------------------------------------------------------------------------------------------------------------------ 201 WAVE HRS ACCUM SC2 G140L 1320 1 60S 1 CYCLE 4 CALIB FOR 202 Comments: BLIND OFFSET FROM NGC1741- OFFSET; ------------------------------------------------------------------------------------------------------------------------------------ 202 NGC1741B HRS ACCUM 2.0 G140L 1320 1 6100S 1 CYCLE 4 Comments: BLIND OFFSET FROM NGC1741- OFFSET; ------------------------------------------------------------------------------------------------------------------------------------ 203 WAVE HRS ACCUM SC2 G140L 1600 1 60S 1 CYCLE 4 CALIB FOR 204 Comments: BLIND OFFSET FROM NGC1741- OFFSET; ------------------------------------------------------------------------------------------------------------------------------------ 204 NGC1741B HRS ACCUM 2.0 G140L 1600 1 12200S 1 CYCLE 4 Comments: BLIND OFFSET FROM NGC1741- OFFSET; ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 5738 [ 6] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HRS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SEARCH-SIZE=5 BRIGHT=RETURN ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO/CAR ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 12.4 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category STELLAR POPULATIONS ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category YOUNG FIELD STARS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements CYCLE 4; ONBOARD ACQ FOR 101; SEQ 100-204 NO GAP CALIB FOR 102; CALIB FOR 104; CALIB FOR 202; CALIB FOR 204; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR-N2 G140L ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC1741-OFFSET NGC1741B ------------------------------------------------------------------------------------------------------------------------------------