6698( 10) - 01/21/97 11:03 - [ 0] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6698 Version: 10 Check-in Date: 21-Jan-1997 11:00:38 1.Proposal Title: High Resolution Imaging of Bubble and Superbubbles in HII Regions ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle INTERSTELLAR MEDIUM GO 6 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: YOU-HUA CHU UNIVERSITY OF ILLINOIS CoI: Sean Points University of Illinois N CoI: Margarita Rosado Instituto de Astronom'\\i a - UNAM N CoI: Kerstin Weis University of Illinois N CoI: Hui Yang University of Illinois N CoI: Dominik Bomans University of Illinois N CoI: G. Garc'\i a-Segura Instituto de Astronom'\\i a - UNAM N CoI: Annie Laval Observatoire de Marseille N ------------------------------------------------------------------------------------ 6. Abstract Massive stars dynamically interact with their ambient interstellar medium via fast stellar winds during their lifetime and via supernova blasts at their demise. The dynamical interaction causes the physical structure of an HII region to evolve along with its ionizing massive stars. Theoretically, it is expected that HII regions around single massive stars will evolve into wind-blown bubbles, and that HII regions around OB associations will evolve into superbubbles. However, observationally, we have found problems of missing bubbles, missing superbubbles, and missing supernova remnants. To investigate these problems, we request WFPC2 images of (1) two bright compact HII regions encompassing young OB associations to search for bubbles around individual massive stars, (2) a bright compact HII region that contains a supernova remnant but lacks a superbubble structure, and (3) three superbubbles with different levels X-ray emission to search for supernova remnant shocks. The results will help us understand better the roles played by stellar winds and supernova remnants in the structure and evolution of the interstellar medium. ------------------------------------------------------------------------------------ Observations Description ------------------------ We request WFPC2 images of three groups of HII regions: (1) two bright compact HII region, N11B and N180B, (2) a bright compact HII region with an embedded SNR, N63, (3) three superbubbles with different levels of X-ray emission, DEML106, N51D, and N44. For the first group of HII regions we will use the F656N filter for HAlpha images and F502N for O III images. The O III filter is selected because the O III/HAlpha ratio is often enhanced in a fast interstellar shock, hence is sometimes a better tracer for expanding bubbles. The O III/HAlpha ratio can also help us examine the morphology of a high- excitation region around a hot star against a low-excitation background. For the second and third groups of HII regions, we will use the F656N filter for HAlpha images and F673N for S II images. The S II images will show the SNR- shocked material. We request one orbit for each HII region. All target HII regions will need one pointing, and the exposure times are 20 minutes in each filter. The average emission measures of the selected fields in N11B, N180B, N63, DEML106, N51D, and N44 are 30000, 10000, 8000, 2200, 7600, 4500 cm^-6 pc, respectively. (Flux in units of erg cm^-2 sec^-1 arcsec^-2 is equal to the emission measure multipled by 1.9times10^-18.) For our target fields, the proposed exposures will produce S/N ratios (per pixle) of 18, 14, 12, 5.5, 12, and 9, respectively, in HAlpha. The O III/HAlpha ratio is ~1 in the features we are searching for, hence the S/N ratios would be similar to those in HAlpha. The S II/HAlpha ratio may reach 0.5--1 in the shocked region, hence the S/N ratios may be slightly lower but still adequate for our proposed search for SNR shocks. Real Time Justification ----------------------- None. Calibration Justification ------------------------- None Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: , ------------------------------------------------------------------------------------ 6698( 10) - 01/21/97 11:03 - [ 1] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 N11B EXT-MEDIUM, HII Region RA=4H 56M 54.4S +/- 0.1S, DEC=- 2000.0 V=300 SURF-LINE(6563)=5.7e-14 66D 24' 58.6" +/- 1" 2 N180B EXT-MEDIUM, HII Region RA=5H 48M 53.4S +/- 0.1S, DEC=- 2000.0 V=300 SURF-LINE(6563)=1.9e-14 70D 04' 45.6" +/- 1" 3 N63 EXT-MEDIUM, HII Region, RA=5H 35M 38.2S +/- 0.1S, DEC=- 2000.0 V=300 SURF-LINE(6563)=1.5e-14 SNR 66D 02' 37.5" +/- 1" 4 N44 EXT-MEDIUM, HII Region, RA=5H 22M 38.5S +/- 0.1S, DEC=- 2000.0 V=300 SURF-LINE(6563)=8.6e-15 Ring Nebula 67D 57' 46.7" +/- 1" Comments: New target pointing given by PI 12/4/96 to find guide stars. 5 N51D EXT-MEDIUM, HII Region, RA=5H 26M 15.20S +/- 0.1S, DEC=- 2000.0 V=300 SURF-LINE(6563)=1.4e-14 Ring Nebula 67D 29' 58.3" +/- 1" 6 DEM106 EXT-MEDIUM, HII Region, RA=5H 13M 51.1S +/- 0.1S, DEC=- 2000.0 V=300 SURF-LINE(6563)=4.2e-15 Ring Nebula 67D 27' 19.1" +/- 0.5" 6698( 10) - 01/21/97 11:03 - [ 2] Visit: 01 Visit Requirements: PCS MODE Fine ORIENTation 155D TO 165D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 N11B WFPC2 IMAGE PC1-FIX F656N CR-SPLIT=0.5 1 1000 S ------------------------------------------------------------------------------------------------------------------------------------ 2 N11B WFPC2 IMAGE PC1-FIX F502N CR-SPLIT=0.5,CR-TOLERANCE=0.0 1 1200 S SAME POSition AS 1 END ORBIT ------------------------------------------------------------------------------------------------------------------------------------ 6698( 10) - 01/21/97 11:03 - [ 3] Visit: 02 Visit Requirements: PCS MODE Fine ORIENTation 130D TO 140D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 N180B WFPC2 IMAGE PC1-FIX F656N CR-SPLIT=0.5,CR-TOLERANCE=0.0 1 1000 S ------------------------------------------------------------------------------------------------------------------------------------ 2 N180B WFPC2 IMAGE PC1-FIX F502N CR-SPLIT=0.5,CR-TOLERANCE=0.0 1 1200 S SAME POSition AS 1 END ORBIT ------------------------------------------------------------------------------------------------------------------------------------ 6698( 10) - 01/21/97 11:03 - [ 4] Visit: 03 Visit Requirements: PCS MODE Fine ORIENTation 265D TO 275D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 N63 WFPC2 IMAGE PC1-FIX F656N CR-SPLIT=0.5,CR-TOLERANCE=0.0 1 1000 S ------------------------------------------------------------------------------------------------------------------------------------ 2 N63 WFPC2 IMAGE PC1-FIX F673N CR-SPLIT=0.5,CR-TOLERANCE=0.0 1 1200 S SAME POSition AS 1 END ORBIT ------------------------------------------------------------------------------------------------------------------------------------ 6698( 10) - 01/21/97 11:03 - [ 5] Visit: 04 Visit Requirements: PCS MODE Fine OREINT 95D TO 105D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 N44 WFPC2 IMAGE PC1-FIX F656N CR-SPLIT=0.5,CR-TOLERANCE=0.0 1 1000 S ------------------------------------------------------------------------------------------------------------------------------------ 2 N44 WFPC2 IMAGE PC1-FIX F673N CR-SPLIT=0.5,CR-TOLERANCE=0.0 1 1200 S SAME POSition AS 1 END ORBIT ------------------------------------------------------------------------------------------------------------------------------------ 6698( 10) - 01/21/97 11:03 - [ 6] Visit: 05 Visit Requirements: PCS MODE Fine ORIENTation 355D TO 5D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 N51D WFPC2 IMAGE PC1-FIX F656N CR-SPLIT=0.5,CR-TOLERANCE=0.0 1 1000 S ------------------------------------------------------------------------------------------------------------------------------------ 2 N51D WFPC2 IMAGE PC1-FIX F673N CR-SPLIT=0.5,CR-TOLERANCE=0.0 1 1200 S SAME POSition AS 1 END ORBIT ------------------------------------------------------------------------------------------------------------------------------------ 6698( 10) - 01/21/97 11:03 - [ 7] Visit: 06 Visit Requirements: PCS MODE Fine ORIENTation 310D TO 320D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 DEM106 WFPC2 IMAGE WF2-FIX F656N CR-SPLIT=0.5,CR-TOLERANCE=0.0 1 1600 S ------------------------------------------------------------------------------------------------------------------------------------ 2 DEM106 WFPC2 IMAGE WF2-FIX F656N CR-SPLIT=NO 1 800 S ------------------------------------------------------------------------------------------------------------------------------------ 6698( 10) - 01/21/97 11:03 - [ 8] Summary Form for Proposal 6698 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=0.5 CR-TOLERANCE=0.0 CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category INTERSTELLAR MEDIUM ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PCS MODE Fine ORIENTation 155D TO 165D SAME POSition AS 1 END ORBIT PCS MODE Fine ORIENTation 130D TO 140D PCS MODE Fine ORIENTation 265D TO 275D PCS MODE Fine OREINT 95D TO 105D PCS MODE Fine ORIENTation 355D TO 5D PCS MODE Fine ORIENTation 310D TO 320D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F656N F502N F673N ------------------------------------------------------------------------------------------------------------------------------------ Target Names N11B N180B N63 N44 N51D DEM106 ------------------------------------------------------------------------------------------------------------------------------------