10537( 2) - 05/13/05 06:46 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 10537 Version: 2 Check-in Date: 13-May-2005 10:45:46 1.Proposal Title: Caught in the Act with HST -- Active Jet Sculpting in the Young Preplanetary Nebulae IRAS 22036+5306 ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle 4. Parallel Pointing Tolerance GO 14 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Dr. Raghvendra Sahai Jet Propulsion Laboratory CoI: Dr. Mark Morris University of California - Los Angeles N CoI: Dr. Carmen Sanchez Contreras California Institute of Technology N CoI: Dr. Mark Claussen Associated Universities, Inc. N ------------------------------------------------------------------------------------ 6. Abstract We have discovered an extended, highly-structured and bipolar nebula surrounding the post-AGB object IRAS22036+5306 (I22036), in a Cycle 10 WFPC2 imaging survey of very young pre-planetary nebulae (PPNs). Young PPNs like I22036, objects in rapid transition between the AGB and Planetary Nebulae (PN) phases, retain direct signatures, in the spatial character of their outflows, of the physical mechanisms which transform slowly expanding, round circumstellar AGB envelopes into highly aspherical PNs with fast-expanding elongated lobes along one or more axes. I22036 shows intriguing evidence for the presence of jets in the HST images, and VLA A- array maps show OH maser emission in a linear structure along the nebular axis. Our ground-based echelle H-alpha spectra show high-velocity blue-shifted absorption in a very broad (~2000 km/s) line profile, and mm-wave CO J=1-0 interferometric data show a bipolar molecular outflow. There are very few young PPNs like I22036 which show clear morphological & kinematical evidence of the presence of jets and their working surfaces, making it unquestionably a key object for understanding how jets can sculpt out bipolar lobes in a progenitor AGB star wind. Using ground-based long-slit spectroscopy with the Keck/ESI, we have partially spatially resolved the H-alpha emission in this object. We now propose to image I22036 in F658N, F631N, F606W and F814W in order to identify accurately the location and structure of the shocked gas, and its relation to the jets and their working surfaces. An important goal is to determine whether we can characterise the forward and reverse shocks near the heads of the knotty jets. The proposed HST imaging will help us to understand the spatio- kinematic structure of the outflowing gas in the bipolar lobes, and allow us to study the relationships between the important dynamical components of this nebula. Supporting ground-based observations such as Zeeman measurements of polarised OH masers with the VLBA to search for magnetic fields in I22036 are being pursued for testing magnetic-collimation models for jets in PPNs. ------------------------------------------------------------------------------------ 10537( 2) - 05/13/05 06:46 - [ 2] Observations Description ------------------------ We will obtain deep 4-point dithered observations with the HRC on ACS through the broad-band F606W \& F814W, and the narrow-band F658N filter. Our goal is to make a significant improvement in sensitivity over the previous SNAPshot imaging observations, where we used relatively short exposure times (typically 8-10 minutes). So we will now use total integration times of about $\sim$2400 sec (1 orbit) each for F606W \& F814W, which will provide a significant improvement over the previous data. We will use F606W images to subtract the continuum from the emission line filter images. The longest exposure time (about 5000 sec) will be used for the F658N imaging, which will contain both scattered (continuum+H$\alpha$) photons, and local H$\alpha$ emission. This will provide a signal-to-noise ratio (S/N)$>$60 in the H$\alpha$ line wings (at $\pm$1000\kms) towards the nebular center and S/N$>$20 towards the lobes. These S/N ratios have been estimated from the intensity of the H$\alpha$ line in one pixel (0.3$''$) of our ESI long-slit spectrum (slit width=0.5$''$, Figure 2) towards the nebular center and towards the lobes and assuming that the H$\alpha$ brightness distribution is roughly uniform within a region with size $<$0.3$''$x0.3$''$. We would like to be able to separate the scattered H$\alpha$ emission from the local emission, either through appropriate differencing or ratioing. We recognize that this may not provide a precise quantitative measurement of the H$\alpha$ intensity because of imperfect removal of the scattered light due to variable circumstellar extinction, but that does not affect the main goal of the proposal, namely to delineate the regions of active shocks in these nebulae. We will also image the OI 6300A emission, which is most likely to be only local emission and not scattered, with WFPC2 through the F631N filter. The exposure time with such a filter will be about 2400\, s with the wide field (WFC) camera mode, which will provide S/N in the line wings (up to $\pm$500\kms) of S/N$>$20 towards the center and S/N$>$7 in the lobes. This S/N has been estimated by taking into account that the OI line is a factor of $\sim$4-5 weaker than H$\alpha$ (from our Keck+ESI spectrum). Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 10537( 2) - 05/13/05 06:46 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 IRAS22036+53 ISM, REFLECTION NEBULA, RA=22H05M30.2800S +/- 0.1", J2000 V = 16.4 06 BIPOLAR OUTFLOW, DEC=+53D21'32.70" +/- 0.1" PLANETARY NEBULA, JET Coordinate Source: HST_IMAGE 10537( 2) - 05/13/05 06:46 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type ACS-HRC-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.15 Line_Spacing 0.098 Coordinate_Frame POS-TARG Pattern_Orient 19.89 Angle_Between_Sides 63.5 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFPC2-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.3535 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 45.0 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 10537( 2) - 05/13/05 06:46 - [ 5] Visit: 01 Visit Priority: Visit Requirements: PCS MODE FINE; SCHED 30% On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 IRAS22036+5 ACS/HRC ACCUM HRC F606W 1 400 S PATTERN 1 1-4 306 ------------------------------------------------------------------------------------------------------------------------------------ 2 IRAS22036+5 ACS/HRC ACCUM HRC F814W 1 800 S 306 ------------------------------------------------------------------------------------------------------------------------------------ 3 IRAS22036+5 ACS/HRC ACCUM HRC F658N 1 638 S 306 ------------------------------------------------------------------------------------------------------------------------------------ 4 IRAS22036+5 ACS/HRC ACCUM HRC F658N 1 638 S 306 ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ IRAS22036+5306 1 ACS/HRC ACCUM HRC F606W 1 none none 1 1 N/A IRAS22036+5306 1 ACS/HRC ACCUM HRC F606W 1 none none 2 1 N/A IRAS22036+5306 1 ACS/HRC ACCUM HRC F606W 2 none none 1 2 N/A IRAS22036+5306 1 ACS/HRC ACCUM HRC F606W 2 none none 2 2 N/A IRAS22036+5306 1 ACS/HRC ACCUM HRC F606W 3 none none 1 3 N/A IRAS22036+5306 1 ACS/HRC ACCUM HRC F606W 3 none none 2 3 N/A IRAS22036+5306 1 ACS/HRC ACCUM HRC F606W 4 none none 1 4 N/A IRAS22036+5306 1 ACS/HRC ACCUM HRC F606W 4 none none 2 4 N/A IRAS22036+5306 2 ACS/HRC ACCUM HRC F814W 1 none none 1 1 N/A IRAS22036+5306 2 ACS/HRC ACCUM HRC F814W 1 none none 2 1 N/A IRAS22036+5306 2 ACS/HRC ACCUM HRC F814W 2 none none 1 2 N/A IRAS22036+5306 2 ACS/HRC ACCUM HRC F814W 2 none none 2 2 N/A IRAS22036+5306 2 ACS/HRC ACCUM HRC F814W 3 none none 1 3 N/A IRAS22036+5306 2 ACS/HRC ACCUM HRC F814W 3 none none 2 3 N/A IRAS22036+5306 2 ACS/HRC ACCUM HRC F814W 4 none none 1 4 N/A IRAS22036+5306 2 ACS/HRC ACCUM HRC F814W 4 none none 2 4 N/A IRAS22036+5306 3 ACS/HRC ACCUM HRC F658N 1 none none 1 1 N/A IRAS22036+5306 3 ACS/HRC ACCUM HRC F658N 1 none none 2 1 N/A IRAS22036+5306 3 ACS/HRC ACCUM HRC F658N 2 none none 1 2 N/A IRAS22036+5306 3 ACS/HRC ACCUM HRC F658N 2 none none 2 2 N/A IRAS22036+5306 3 ACS/HRC ACCUM HRC F658N 3 none none 1 3 N/A IRAS22036+5306 3 ACS/HRC ACCUM HRC F658N 3 none none 2 3 N/A IRAS22036+5306 3 ACS/HRC ACCUM HRC F658N 4 none none 1 4 N/A 10537( 2) - 05/13/05 06:46 - [ 6] Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ IRAS22036+5306 3 ACS/HRC ACCUM HRC F658N 4 none none 2 4 N/A IRAS22036+5306 4 ACS/HRC ACCUM HRC F658N 1 none none 1 1 N/A IRAS22036+5306 4 ACS/HRC ACCUM HRC F658N 1 none none 2 1 N/A IRAS22036+5306 4 ACS/HRC ACCUM HRC F658N 2 none none 1 2 N/A IRAS22036+5306 4 ACS/HRC ACCUM HRC F658N 2 none none 2 2 N/A IRAS22036+5306 4 ACS/HRC ACCUM HRC F658N 3 none none 1 3 N/A IRAS22036+5306 4 ACS/HRC ACCUM HRC F658N 3 none none 2 3 N/A IRAS22036+5306 4 ACS/HRC ACCUM HRC F658N 4 none none 1 4 N/A IRAS22036+5306 4 ACS/HRC ACCUM HRC F658N 4 none none 2 4 N/A 10537( 2) - 05/13/05 06:46 - [ 7] Visit: 02 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 IRAS22036+5 WFPC2 IMAGE PC1 F631N CR-SPLIT=0.5,CLOCKS=YES 1 500 S PATTERN 2 1 306 see below ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ IRAS22036+5306 1 WFPC2 IMAGE PC1 F631N 1 none none 1 1 500.0 S IRAS22036+5306 1 WFPC2 IMAGE PC1 F631N 1 none none 2 1 500.0 S IRAS22036+5306 1 WFPC2 IMAGE PC1 F631N 2 none none 1 1 500.0 S IRAS22036+5306 1 WFPC2 IMAGE PC1 F631N 2 none none 2 1 500.0 S 10537( 2) - 05/13/05 06:46 - [ 8] Summary Form for Proposal 10537 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures HRC PC1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/HRC WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=0.5 CLOCKS=YES ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PCS MODE FINE; SCHED 30% PATTERN 1 1-4 PATTERN 2 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F606W F814W F658N F631N ------------------------------------------------------------------------------------------------------------------------------------ Target Names IRAS22036+5306 ------------------------------------------------------------------------------------------------------------------------------------