5963( 12) - 11/22/95 13:32 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 5963 Version: 12 Check-in Date: ********** 1.Proposal Title: Search for Externally Illuminated Proto- Planetary Systems in S106 and NGC281 ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle Interstellar Medium GO 5 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: John Bally Center for Astrophysics and Space Astronomy, University of Colorado CoI: Ralph Sutherland Joint Institute for Laboratory N Astrophysics, University of Colorado CoI: John Rayner Institute for Astronomy, University of N Hawaii CoI: Hans Zinnecker Astronomy Institute, Wuerzburg University N CoI: David Devine Center for Astrophysics and Space Y Astronomy, University of Colorado ------------------------------------------------------------------------------------ 6. Abstract Our primary goal is to search for externally illuminated protostellar and protoplanetary environments (``proplyds'') embedded in the H II region S106 using WFPC2. Our search will attempt to constrain the photo-evaporation time-scale for proplyds by determining the frequency of occurrence as a function of the photoionization age of the host HII region which for S106 is about 10^4 years and for M42 (the only HII region in which proplyds have been found so far) is about 10^5 years. Our observations will constrain the frequency of occurrence of proto- planetary environments amongst young stellar objects born in transient (gravitationally unbound) cluster environments where most field stars are believed to be born. S106 is so young that its structure may provide information about the bipolar outflow phase that preceded the birth of the HII region. HST will help distinguish stars from nebulosity and resulting photometry and colors will be combined with near -IR data to fit stars on the HR diagram. ------------------------------------------------------------------------------------ 5963( 12) - 11/22/95 13:32 - [ 2] Observations Description ------------------------ We will search for proplyds in the 6563 Angstrom\ Halpha filter (F656N). Using ground based data for the mean flux from the nebula, we estimate that exposure times totaling 700 to 2100 seconds will be required to obtain sufficient S/N. We will attempt to use use partial pixel substepping and the Lucy-Hook coaddition code (ST-ECF Newsletter, Feb 1995, #22, 16.) to improve the spatial resolution of the WFPCII images. Therefore, we will obatin two high S/N images at each of three pointings needed to cover S106. We estimate that each pointing will use one full orbit when the substepped exposures are included. We will also obtain continuum images in the F547M filter that can be used to distinguish refelcted light from nebula emission. We have obtained extensive ground based supporting data for this program. Near-IR S106 images were obtained by John Rayner with the CFHT (hi-res) and the UH 88-inch (low-res, wide-field). John Rayner has obtained thermal images with the IRTF in October. The K - L infrared color index is an indication of circumstellar matter, possibly in the form of a disk. Plans are underway to use these instruments for hi-res follow-up IR imaging when tip-tilt adaptive optics become available at the IRTF. J. Bally and D. Devine have obtained extensive narrow band visual images from the ground of S106. J. Bally has obtained aperture synthesis radio maps of S106 with the VLA. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_address Ship Via: UPS Email: , ------------------------------------------------------------------------------------ 5963( 12) - 11/22/95 13:32 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 S106N ISM, HII Region RA=20H 25M 34.30S +/-.1S, 1950 SURF-LINE(6563)=5.0 E-13 DEC=37D 13' 04.0" +/-1" 2 S106S ISM, HII Region RA=20H 25M 33.30S +/-.1S, 1950 SURF-LINE(6563)=5.0 E-13 DEC=37D 12' 36.0" +/-1" 3 S106N2 ISM, HII Region RA=20H 25M 35.30S +/-.1S, 1950 SURF-LINE(6563)=5.0 E-13 DEC=37D 13' 32.0" +/-1" 5963( 12) - 11/22/95 13:32 - [ 4] Visit: 01 Visit Requirements: ORIENT 20D TO 30D 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 S106N WFPC2 IMAGE PC1 F656N 2 300S Comments: H-ALPHA LINE ------------------------------------------------------------------------------------------------------------------------------------ 2 S106N WFPC2 IMAGE PC1 F656N 2 300S POS TARG +1.05, +1.05 ------------------------------------------------------------------------------------------------------------------------------------ 3 S106N WFPC2 IMAGE PC1 F547M 1 100S Comments: CONTINUUM ------------------------------------------------------------------------------------------------------------------------------------ 5963( 12) - 11/22/95 13:32 - [ 5] Visit: 02 Visit Requirements: ORIENT 200D TO 210D 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 ------------------------------------------------------------------------------------------------------------------------------------ 4 S106S WFPC2 IMAGE PC1 F656N 2 300S ------------------------------------------------------------------------------------------------------------------------------------ 5 S106S WFPC2 IMAGE PC1 F656N 2 300S POS TARG +1.05, +1.05 ------------------------------------------------------------------------------------------------------------------------------------ 6 S106S WFPC2 IMAGE PC1 F547M 1 100S ------------------------------------------------------------------------------------------------------------------------------------ 5963( 12) - 11/22/95 13:32 - [ 6] Visit: 03 Visit Requirements: ORIENT 20D TO 30D 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 ------------------------------------------------------------------------------------------------------------------------------------ 7 S106N2 WFPC2 IMAGE PC1 F656N 2 300S ------------------------------------------------------------------------------------------------------------------------------------ 8 S106N2 WFPC2 IMAGE PC1 F656N 2 300S POS TARG +1.05, +1.05 ------------------------------------------------------------------------------------------------------------------------------------ 9 S106N2 WFPC2 IMAGE PC1 F547M 1 100S ------------------------------------------------------------------------------------------------------------------------------------ 5963( 12) - 11/22/95 13:32 - [ 7] Summary Form for Proposal 5963 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category Interstellar Medium ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 20D TO 30D POS TARG +1.05, +1.05 ORIENT 200D TO 210D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F656N F547M ------------------------------------------------------------------------------------------------------------------------------------ Target Names S106N S106S S106N2 ------------------------------------------------------------------------------------------------------------------------------------