6122( 8) - 11/22/95 15:30 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6122 Version: 8 Check-in Date: ********** 1.Proposal Title: High-Resolution Imaging of Shocks in 30 Doradus ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle Interstellar Medium GO 5 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: You-Hua Chu University of Illinois CoI: Bart Wakker University of Illinois N CoI: Sean Points University of Illinois N CoI: Mordecai Mac Low University of Illinois N CoI: Robert Kennicutt University of Arizona N CoI: Chris Smith Cerro Tololo InterAmerican Obs N CoI: Dominik Bomans Sternwarte der Universitaet Bonn N ------------------------------------------------------------------------------------ 6. Abstract 30 Doradus in the Large Magellanic Cloud is the nearest giant H II region. It provides a unique opportunity to study the interactions between a large number of massive stars and the interstellar medium. It contains large shell structures that emit bright diffuse X-rays and show shocked material at DeltaV up to 300 kms. HST WFPC2 images only exist for the central 2min point5 of 30 Dor, where the interstellar and stellar conditions are vastly different from those in the supershells in outlying regions. Therefore, we request WFPC2 images of three of these shells in the H Alpha S II and O III emission lines. With the high spatial resolution we can for the first time image SNR shocks in superbubbles, study the cloudy medium of a giant H II region, map cloud-cloud collisions, model a supershell around a cluster, and search for circumstellar shells around massive stars. ------------------------------------------------------------------------------------ 6122( 8) - 11/22/95 15:30 - [ 2] Observations Description ------------------------ We were awarded three orbits for one target. We select Target 3 in our Phase I proposal. We will take WFPC2 images with 6 filters: three centered on nebular lines - F656N, F502N, and F673N, and three centered on stellar continumm - F336W, F555W, and F814W. The continuum images will be used to study stellar photometry and the line images will be used to study the physical structure of shocked gas and ioonization fronts. The exposure times are: F656N - 20 min with CR-SPLIT; F502N - 20 min with CR-SPLIT; F673N - 50 min with CR-SPLIT; F336W - 10 sec, 200 sec with CR-SPLIT; F555W - 4 sec, 40 sec, and 2x200 sec; F814W - 5 sec, 200 sec with CR-SPLIT. We want the PC centered on a small cluster and the WFC centered on a fast-expanding shell. Therefore, we want the PC to be at the north, and the chevron of the WFC to be pointing south. Exposure times were estimated using the description provided by Biretta (1994, personal communication) to obtain a desired S/N ratio of 3 per WFPC2 WF pixel. Exposure times of 20 minutes using filters F502N and F656N allow us to detect limiting emission measures of 1550 and 495 cm^-6 pc, respectively. This corresponds to fluxes of 2.9times10^-15 and 9.4times10^-16 erg cm^-2 sec^-1 arcsec^-2. An exposure time of 50 minutes with filter F673N allows us to detect down to an emission measure of 7000, 700, and 300 cm^-6 pc for assumed the S II to H Alpha\ ratio of 0.03, 0.3, and 0.7, respectively. Our analysis of flux-calibrated echelle data of 30 Dor (Chu and Kennicutt 1994) shows that the mean emission measures in this region are 19000 cm^-6 pc, and the shocked components have emission measures of a few 10^2 to a few 10^3. Thus, we will be able to observe the fainter structures in this region. 30 Dor can be observed in CVZ 2-3 times a year. If the observations are carried out in CVZ, we can make the observations more efficient. Real Time Justification ----------------------- None. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_address Ship Via: UPS Email: , ------------------------------------------------------------------------------------ 6122( 8) - 11/22/95 15:30 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC2070-NW- ISM, HII Region, SNR RA=5H 38M 17.0S +/- 0.37S, DEC=- J2000 V=12.5 B-V=-0.06 SHELL 69D 04' 02.0" +/- 5.0", PLATE- ID=06B0 6122( 8) - 11/22/95 15:30 - [ 4] Visit: 01 Visit Requirements: ORIENTation 0D TO 10D On Hold Comments: Additional Comments: PC at north and WFC at south; position angle 0D. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC2070-NW- WFPC2 IMAGE PC1-FIX F656N 6563 CR-SPLIT=0.5 , 1 1400S SHELL CR- TOLERANCE=0.0 ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC2070-NW- WFPC2 IMAGE PC1-FIX F555W 5407 ATD-GAIN=15 1 4S SHELL ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC2070-NW- WFPC2 IMAGE PC1-FIX F555W 5407 1 40S SHELL ------------------------------------------------------------------------------------------------------------------------------------ 4 NGC2070-NW- WFPC2 IMAGE PC1-FIX F555W 5407 CR-SPLIT=0.5 , 1 400S SHELL CR- TOLERANCE=0.0 ------------------------------------------------------------------------------------------------------------------------------------ 5 NGC2070-NW- WFPC2 IMAGE PC1-FIX F673N 6732 CR-SPLIT=NO 1 1400S SHELL ------------------------------------------------------------------------------------------------------------------------------------ 6 NGC2070-NW- WFPC2 IMAGE PC1-FIX F502N 5013 CR-SPLIT=NO 1 700S SHELL ------------------------------------------------------------------------------------------------------------------------------------ 7 NGC2070-NW- WFPC2 IMAGE PC1-FIX F336W 3344 ATD-GAIN=15 1 10S SHELL ------------------------------------------------------------------------------------------------------------------------------------ 8 NGC2070-NW- WFPC2 IMAGE PC1-FIX F336W 3344 CR-SPLIT=0.5 , 1 200S SHELL CR- TOLERANCE=0.0 ------------------------------------------------------------------------------------------------------------------------------------ 9 NGC2070-NW- WFPC2 IMAGE PC1-FIX F673N 6732 CR-SPLIT=NO 1 1400S SHELL ------------------------------------------------------------------------------------------------------------------------------------ 10 NGC2070-NW- WFPC2 IMAGE PC1-FIX F502N 5013 CR-SPLIT=NO 1 700S SHELL ------------------------------------------------------------------------------------------------------------------------------------ 11 NGC2070-NW- WFPC2 IMAGE PC1-FIX F814W 7940 ATD-GAIN=15 1 5S SHELL ------------------------------------------------------------------------------------------------------------------------------------ 12 NGC2070-NW- WFPC2 IMAGE PC1-FIX F814W 7940 CR-SPLIT=0.5 , 1 200S SHELL CR- TOLERANCE=0.0 ------------------------------------------------------------------------------------------------------------------------------------ 6122( 8) - 11/22/95 15:30 - [ 5] Summary Form for Proposal 6122 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=0.5 CR-TOLERANCE=0.0 ATD-GAIN=15 CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category Interstellar Medium ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENTation 0D TO 10D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F656N F555W F673N F502N F336W F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC2070-NW-SHELL ------------------------------------------------------------------------------------------------------------------------------------