Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 5365 Report Date: 18-Jul-95:17:14 Version: ********** Check-in Date: ********** 1.Proposal Title: PROBING EXCITATION MECHANISMS AND ABUNDANCES IN YOUNG MAGELLANIC CLOUD SNRS - CYCLE 4 MED:EARLY ACQ FOR 5607 ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID INTERSTELLAR MEDIUM GO Sub Category SN & SNR ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone William P. Blair 2380 USA 410-516-8447 ------------------------------------------------------------------------------------ 7. Abstract We will obtain WFPC2 images and FOS spectra of a young, oxygen- rich supernova remnant called N132D in the Magellanic Cloud. The images will be used to study fine- scale spatial and ionization structures within the knotty filaments, and also provide EARLY ACQ exposures for the spectroscopy. The FOS will be used to obtain UV/optical spectra of chemically and kinematically distinct knots in the object. Only HST has the resolution necessary to isolate individual knots for study. Having UV and optical data with the same apertures in the same positions will for the first time provide reliable relative intensities of UV and optical lines for comparison with theoretical models. This will provide a critical test of the emission mechanisms and allow us to derive reliable elemental abundances. The HST data will provide important tests of theories of nucleosynthesis in massive stars and will allow an improved understanding of the dynamics of SN explosions and mixing in the ejecta. ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 13.20 par: 0 10. Num targs pri: 6 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: FOS WF/PC ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 5365 PI: William P. Blair Proposal Title: PROBING EXCITATION MECHANISMS AND ABUNDANCES IN YOUNG MAGELLANIC CLOUD SNRS - CYCLE 4 MED:EARLY ACQ FOR 5607 ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ William P. Blair 2380 USA Knox S. Long 3470 USA P. Frank Winkler 2680 USA Robert P. Kirshner 2170 USA John C. Raymond 2166 USA Jon A. Morse 3470 USA Michael A. Dopita 4140 AUSTRALIA Ralph S. Sutherland 1764 USA ------------------------------------------------------------------------------------ 3. Description of proposed observations. We request WFPC2 F502N, F375N, F673N, and F547M exposures of N132D. These exposures will be used to study small scale structure in the ejecta that dominates the emission from this object. Knots in Cas A, for example, range from unresolved to several arcsec in dimension. Even though N132D is roughly 20x more distant than Cas A, HST will resolve considerable structure. The F502N exposure will be most important for this because [O III] 5007 is bright and the HST/WFPC2 throughput is relatively good. The F375N exposure will allow the ionization structure of the filaments to be assessed from the [O II]3727 emission. (Note: this will only be possible for filaments whose radial velocities are fully within the bandpasses of the filters.) The F673N exposure will show emission from [S II]6717,6731 for comparison. These data will also be used as "EARLY ACQ" images, permitting us to make appropriate choices of FOS aperture sizes and placements to isolate knots for study. F547M is needed as a "continuum" band to assess the difference between faint stars and stellar-appearing emission knots (important since N132D is in the bar of the LMC). Total exposure through each filter will be split in half for easier cosmic ray removal. We will place the 1" circular (or smaller if appropriate) FOS aperture on three chemically-distinct knots in N132D. The three positions in N132D are the minimum needed to sample (a) O-emitting and (b) S-emitting material in the inner ejecta, and (c) an out-lying filament showing emission in H-alpha, [S II], and [O III]. We assume exposures with FOS/BL G160L (6000s), and FOS/RD G270H (3400s), G400H (1000s), and G570H (1400s) at each of the three positions. G160L is considerably lower resolution than the other gratings, but covers the FUV range of interest with one grating. Combined UV/optical data are requested with the same apertures in the same positions to provide accurate relative line intensities for comparison with theoretical calculations. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. We have worked hard with IUE to obtain the existing UV data on N132D. These spectra are all lengthy double-shift IUE exposures, but IUE simply can't resolve individual knots. Hence, blending of material with differing abundances and physical conditions hampers an accurate comparison with models. It has also been difficult to accurately combine optical and UV data taken with different instruments and with differing aperture sizes and placements. HST will provide both the spatial resolution and the combined UV/optical coverage with the same slit in the same position to make a quantitative difference in the comparison against calculated models. Page 3 ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. None. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. None. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. Some of the filamentary structures in these objects are extended on the several arcsec scale and, with our existing ground-based imaging data, we could measure positions of offset stars and filaments directly. However, previous experience with EARLY ACQ WFPC exposures has demonstrated that ground-based data can sometimes be deceptive. Blair and Davidsen (1993) have shown how an FOS blind offset based on ground- based images would have "missed" the bulk of the emission in an M33 supernova remnant, for example. With the amount of time to be spent on the spectroscopy, we strongly prefer the method of obtaining EARLY ACQ images and basing the FOS blind offset acquisition on these data. And of course, the images are of intrinsic interest in their own right for the spatial and ionization structure they will show. ------------------------------------------------------------------------------------ 9. Description of previous HST work. Here is a listing of other programs involving the scientists on this proposal, as copied from Phase I submission. P2417: "CAS A: The Remnant of a Massive Supernova"; Kirshner, Blair, Long, Winkler, and Raymond P2563: "SINS--The Supernova INtensive Survey"; Kirshner et al. P3853: "SINS: The Supernova INtensive Study - 87A revisit" P4016: "SINS: The Supernova INtensive Study - cyc 1 opportunity" P4022: "SINS: The Supernova INtensive Study - 87A revisit" P4252: "SINS: Late Time Observations of SN1992A" P4528: "SINS: The Supernova INtensive Study - cyc 2 opportunity" P4445: "SINS: The Supernova INtensize Study - cyc 3" P2266: "Post Asymptotic Giant Branch Evolution in the Magellanic Clouds"; Dopita. P2243: "Shock Wave Structures of HH Objects"; Schwartz et al. (Raymond Co-I) P4674: "Molecular Emission in HH47"; Raymond et al. [No Obs. yet] P3683: "Accretion Disk Mapping in CVs"; Horne et al. (Long and Raymond Co-Is) P3836: "Spectroscopic Obs. od Exposed WDs in CVs"; Sion et al. (Long Co-I) Other SUPPLEMENTAL or PARALLEL programs not shown. Also, Blair is involved with some FOS GTO programs, although not as an "official" Co-I. Page 4 ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). Astrophysics at JHU has grown dramatically over the last decade. The JHU Center for Astrophysical Sciences provides an excellent research environment, with a fully qualified staff and a wide range of research expertise within its membership. JHU/CAS operates a computer center which is responsible for a wide range of services to its users, from maintenance of networks and machines to upgrades of software (including IRAF/STSDAS) to I/O devices and services. The PI has a SPARCstation 10 which has been purchased with monies from various NASA- related research grants he has received. This will provide state-of-the-art computer support for reduction and analysis of these data. No hardware is requested with this proposal, although some support of ongoing maintenance on this machine will be requested. STScI and the Harvard-Smithsonian Center for Astrophysics are, of course, first rate astronomical research institutions with state-of- the-art facilities, including computer hardware and software technicians, photo labs, and libraries, all of which will provide support as needed. At Middlebury College, the astronomical image-processing laboratory has a network of three Sparcstations running IRAF/STSDAS. These are now used for analysis of optical and X-ray data obtained by faculty and students at major ground- and space-based observatories, as well as images from a CCD camera mounted on a local 0.4-m telescope. Many Middlebury undergraduates develop substantial expertise in astronomical image processing. Not only would access to HST data be stimulating to them, but they will also be able to make a genuine contribution to the analysis. All resources required by Dopita will be provided by Mt Stromlo and Siding Spring Observatories. He has a SPARC II which will be used in the modelling. ------------------------------------------------------------------------------------ 11. Address Information Name: William P. Blair Category: PI Institution: 2380 Address: 237 BLOOMBERG CENTER DEPARTMENT OF PHYSICS AND ASTRONOMY JOHNS HOPKINS UNIVERSITY City: Baltimore State: MD Zip Code: 21218 Country: USA Telephone: 410-516-8447 Telex (or e-mail): 410-516-8260 ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 5365 [ 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 N132D H, RA = 05H 25M 26.0S +/- 3", 1950 1 SURF-LINE(5007) = 2.6 +/- 0.5 E-15 506 DEC = -69D 40' 48" +/- 3" Comments: CORRECTED CENTER OF EXTENDED SNR EMISSION; USE FOR WFPC2 IMAGES. CENTERS SW OF BRT. OPTICAL ARC. ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 5365 [ 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 N132D WFPC2 IMAGE WF3 F502N 5013 CR-SPLIT=NO 2 1800S 1 CYCLE 4 POS TARG -6.8,- 11.8 SAME POS FOR 2-4 AS 1 ORIENT 203D +/- Comments: EARLY ACQ FOR PROGRAM 5607 THE 10D FOS EXPOSURES HAVE BEEN SPLIT ------------------------------------------------------------------------------------------------------------------------------------ 2 N132D WFPC2 IMAGE WF3 F375N 3737 CR-SPLIT=NO 2 2000S 1 CYCLE 4 POS TARG -6.8,- 11.8 Comments: EARLY ACQ AND SCIENCE EXPOSURE. THE FOS EXPOSURES HAVE BEEN SPLIT FROM THIS PROGRAM ------------------------------------------------------------------------------------------------------------------------------------ 3 N132D WFPC2 IMAGE WF3 F673N 6732 CR-SPLIT=NO 2 1800S 2 CYCLE 4 POS TARG -6.8,- 11.8 Comments: EARLY ACQ AND SCIENCE EXPOSURE. THE FOS EXPOSURES HAVE BEEN SPLIT FROM THIS PROGRAM ------------------------------------------------------------------------------------------------------------------------------------ 4 N132D WFPC2 IMAGE WF3 F547M 5479 1 900S 1 CYCLE 4 POS TARG -6.8,- 11.8 Comments: EARLY ACQ AND SCIENCE EXPOSURE. USE TO DISCRIMINATE STARS. THE FOS EXPOSURES HAVE BEEN SPLIT FROM THIS PROGRAM ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 5365 [ 7] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 13.20 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category INTERSTELLAR MEDIUM ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category SN & SNR ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements CYCLE 4; POS TARG -6.8,-11.8; SAME POS FOR 2-4 AS 1; ORIENT 203D +/- 10D; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F502N F375N F673N F547M ------------------------------------------------------------------------------------------------------------------------------------ Target Names N132D ------------------------------------------------------------------------------------------------------------------------------------