9721( 4) - 05/23/03 11:26 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 9721 Version: 4 Check-in Date: 23-May-2003 11:23:32 1.Proposal Title: The Kinematics and Dynamics of the Material Surrouding Eta Carinae ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 12 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Mr. Bryan N. Dorland United States Naval Observatory CoI: Dr. Douglas G. Currie University of Maryland N CoI: Dr. Arsen R. Hajian United States Naval Observatory N ------------------------------------------------------------------------------------ 5. Abstract We propose a series of observations using ACS/HRC that will perform astrometric measurements of the ejecta around eta Car. We will observe ejecta in three distinct regions: the inner (characterized by the close-in debris such as the Weigelt blobs), the intermediate (primarily the equatorial disk), and the outer (the homunculus and the North and South Jet structures). These observations will provide second and third epoch measurements vs. previous WFPC2 data. The resultant significantly increased temporal baseline (with corresponding decreases in proper motion, date of origin and 3D orientation errors) will allow for the detection of acceleration and non-radial motion in the ejecta, testing the canonical hypothesis of ballistic motion. A secondary goal of the observations will be to compare the HRC measurements with concurrent Cycle 12 WFPC2 measurements taken by other observers (who have indicated they will release their data immediately) is order to provide a calibration link between the WFPC2 and HRC astrometric frames. Our proposed HRC observations will require three HST orbits. ------------------------------------------------------------------------------------ 9721( 4) - 05/23/03 11:26 - [ 2] Observations Description ------------------------ The goal of the HRC observations is to perform high-precision relative astrometry of eta Carinae's central star, ejecta, and debris field features. We will compare these measurements with previous WFPC2 and HRC observations in order to establish relative proper motions and explore the possibility of non- ballistic (accelerated) motion in eta Car's debris field. We will also compare these HRC observations with same epoch (Cycle 12) WFPC2 observations being carried out as part of the eta Car Legacy project in order to determine the systematic errors that arise between the HRC and WFPC astrometric reference frames. We propose observing eta Car using HRC with a series of filter settings similar to the WFPC2 filter bands that were used in previous observations. This will allow us to use these HRC observations as second and third epoch measurements with a temporal baseline that extends back to 1995. We will concentrate on three primary bands: F660N (cf. WFPC2 F658N), F330W (cf. WFPC2 F336W) and FR914M, centered at 10201 angstroms (cf. WFPC2 F1042M). For each of these filter bands, we will take a complete set of exposures that spans the fluxes ranging from central star to outer debris. We will supplement these observations with a second set of exposures consisting of FR459M centered at 4070 (cf. WFPC2 F410M), F550M (cf. WFPC2 F569W), and FR656N centered at 6770 (for direct observation of the [S II] features at 6114 and 6731) that will be used to look only at the central star and innermost debris. The central star and debris field around eta Car span a very large range of flux, with the central star having a V-band magnitude of approximately 6.2 while the outer debris has a much lower surface brightness. Since we are interested in astrometry relative to the central star, we have chosen a sequence of exposure times that run 0.1, 1.0, 10.0 and 200-400 sec (band dependent) in the three primary bands of interest. This sequence will allow us to maintain S/N > 100 for all major debris features down to the faintest ones observed in our sequences. Using these sets of exposure times, we will be able to calculate relative separation between the central star and all observed objects. We have chosen an orientation angle range of ORIENT = 81.5D ? 87.5D. This was chosen so as to position the HRC +Y axis approximately East and the +X axis approximately South. In this orientation, the diffraction spikes will run along the X and Y axes and blooming will be along the Y axis. This orientation is necessary to avoid placing the diffraction spikes and blooming direction on top of either the "North Jet" (PA = 25 D) or Malin spikes 1 or 2 (PAs = 150D, 167D), both of which are dim features that will only be observed in the longest exposures. Since the purpose of the observations is to take high-precision astrometric measurements, we will employ sub-pixel dithering for all exposures in order to achieve maximum spatial resolution. We will use a standard ACS-HRC Dither Box pattern, with four sub-exposures at 150 mas offsets. Using this dithering scheme has the added benefit of allowing for cosmic ray and hot pixel rejection. Real Time Justification ----------------------- Calibration Justification ------------------------- 9721( 4) - 05/23/03 11:26 - [ 3] Additional Comments ------------------- ------------------------------------------------------------------------------------ 9721( 4) - 05/23/03 11:26 - [ 4] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 HD93308 STAR, LUMINOUS BLUE RA=10H45M3.54S +/- 0.25", DEC=- J2000 V = 6.2 VARIABLE, EJECTA, ETA 59D41'3.95" +/- 0.25" SURF-BKG(V) = 10.5 CARINAE STAR, SHELL, FILAMENT Coordinate Source: HIPPARCOS/TYCHO_CATALOGUE Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1991.25 -0.000470000 0.0045 0.0 9721( 4) - 05/23/03 11:26 - [ 5] 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 Coordinate_Frame POS-TARG Pattern_Orient 19.89 Center_Pattern YES ------------------------------------------------------------------------------------------------------------------------------------ 9721( 4) - 05/23/03 11:26 - [ 6] Visit: 01 Visit Priority: Visit Requirements: SCHED 30% ORIENT 84.5D TO 94.5 D ORIENT 264.5D TO 274.5 D On Hold Comments: Additional Comments: ORIENT angle chosen to place +Y axis between PA = 261.5 D and 267.5D. Resultant blooming will be approximately along Y axis and diffraction spikes will be along X and Y axes. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 HD93308 ACS/HR ACCUM HRC F660N CR-SPLIT=NO,GAIN=4 1 0.1 S PATTERN 1 1-5 C ------------------------------------------------------------------------------------------------------------------------------------ 2 HD93308 ACS/HR ACCUM HRC F660N CR-SPLIT=NO,GAIN=4 1 1 S C ------------------------------------------------------------------------------------------------------------------------------------ 3 HD93308 ACS/HR ACCUM HRC F660N CR-SPLIT=NO,GAIN=4 1 10 S C ------------------------------------------------------------------------------------------------------------------------------------ 4 HD93308 ACS/HR ACCUM HRC F660N CR-SPLIT=NO,GAIN=4 1 412 S C ------------------------------------------------------------------------------------------------------------------------------------ 5 HD93308 ACS/HR ACCUM HRC FR459M 4070 CR-SPLIT=NO,GAIN=4 1 1 S C ------------------------------------------------------------------------------------------------------------------------------------ 9721( 4) - 05/23/03 11:26 - [ 7] Visit: 02 Visit Priority: Visit Requirements: SAME ORIENT AS 01 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 HD93308 ACS/HR ACCUM HRC F550M CR-SPLIT=NO,GAIN=4 1 0.1 S PATTERN 1 1-7 C ------------------------------------------------------------------------------------------------------------------------------------ 2 HD93308 ACS/HR ACCUM HRC F550M CR-SPLIT=NO,GAIN=4 1 1 S C ------------------------------------------------------------------------------------------------------------------------------------ 3 HD93308 ACS/HR ACCUM HRC F330W CR-SPLIT=NO,GAIN=4 1 0.1 S C ------------------------------------------------------------------------------------------------------------------------------------ 4 HD93308 ACS/HR ACCUM HRC F330W CR-SPLIT=NO,GAIN=4 1 1 S C ------------------------------------------------------------------------------------------------------------------------------------ 5 HD93308 ACS/HR ACCUM HRC F330W CR-SPLIT=NO,GAIN=4 1 10 S C ------------------------------------------------------------------------------------------------------------------------------------ 6 HD93308 ACS/HR ACCUM HRC F330W CR-SPLIT=NO,GAIN=4 1 238 S C ------------------------------------------------------------------------------------------------------------------------------------ 7 HD93308 ACS/HR ACCUM HRC FR459M 4070 CR-SPLIT=NO,GAIN=4 1 0.1 S C ------------------------------------------------------------------------------------------------------------------------------------ 9721( 4) - 05/23/03 11:26 - [ 8] Visit: 03 Visit Priority: Visit Requirements: SAME ORIENT AS 01 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 HD93308 ACS/HR ACCUM HRC FR505N 4870 CR-SPLIT=NO,GAIN=4 1 0.1 S PATTERN 1 1-7 C ------------------------------------------------------------------------------------------------------------------------------------ 2 HD93308 ACS/HR ACCUM HRC FR505N 4870 CR-SPLIT=NO,GAIN=4 1 1 S C ------------------------------------------------------------------------------------------------------------------------------------ 3 HD93308 ACS/HR ACCUM HRC FR656N 6770 CR-SPLIT=NO,GAIN=4 1 0.1 S C ------------------------------------------------------------------------------------------------------------------------------------ 4 HD93308 ACS/HR ACCUM HRC FR656N 6770 CR-SPLIT=NO,GAIN=4 1 1 S C ------------------------------------------------------------------------------------------------------------------------------------ 5 HD93308 ACS/HR ACCUM HRC FR914M 10201 CR-SPLIT=NO,GAIN=4 1 1 S C ------------------------------------------------------------------------------------------------------------------------------------ 6 HD93308 ACS/HR ACCUM HRC FR914M 10201 CR-SPLIT=NO,GAIN=4 1 10 S C ------------------------------------------------------------------------------------------------------------------------------------ 7 HD93308 ACS/HR ACCUM HRC FR914M 10201 CR-SPLIT=NO,GAIN=4 1 265 S C ------------------------------------------------------------------------------------------------------------------------------------ 9721( 4) - 05/23/03 11:26 - [ 9] Summary Form for Proposal 9721 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures HRC ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/HRC ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO GAIN=4 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements SCHED 30% ORIENT 84.5D TO 94.5 D ORIENT 264.5D TO 274.5 D PATTERN 1 1-5 SAME ORIENT AS 01 PATTERN 1 1-7 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F660N FR459M F550M F330W FR505N FR656N FR914M ------------------------------------------------------------------------------------------------------------------------------------ Target Names HD93308 ------------------------------------------------------------------------------------------------------------------------------------ Wavelengths 4070 4870 6770 10201 ------------------------------------------------------------------------------------------------------------------------------------