8222( 4) - 08/23/01 07:58 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8222 Version: 4 Check-in Date: 11-Mar-1999 06:32:10 1.Proposal Title: An Emission Line Survey of the Crab Nebula ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 8 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Jeff Hester Arizona State University CoI: Dr. William Blair The Johns Hopkins University N CoI: Dr. Ravi Sankrit The Johns Hopkins University N CoI: Dr. Paul Scowen Arizona State University N ------------------------------------------------------------------------------------ 5. Abstract We propose to conduct a WFPC2 survey of the Crab Nebula in the light of emission from O I, S II, and O III, and in a single continuum band. WFPC2 observations have already dramatically reshaped our understanding of the Crab. They have shown that the filaments in the Crab are the result of Rayleigh-Taylor instabilities at the surface of the synchrotron nebula. These data also provide the first direct evidence of the existence of an extended remnant of freely expanding ejecta that surrounds the visible nebula and into which the synchrotron nebula is expanding. High spatial resolution observations of the range of conditions around the R-T unstable interface are needed if we are to develop this understanding further or apply it to questions of the overall structure and evolution of the remnant. We have also found that the subarcsecond structure of filaments strongly influences overall filament spectra. Detailed knowledge of the ionization structure of filaments at HST resolution is essential to interpret any spectroscopic observations of the Crab, and is needed in particular if we are to disentangle such structural effects from the spatial abundance distribution within the nebula. In addition to our specific scientific objectives, this survey will provide a data set that is essential to all future studies of the structure, dynamics, and evolution of the Crab. ------------------------------------------------------------------------------------ 8222( 4) - 08/23/01 07:58 - [ 2] Observations Description ------------------------ Using near-nominal roll angles of 265degrees\ and 85degrees (each of which is achievable during approximately half of the Crab's visibility) we find that we can image the entire Crab Nebula at WFC resolution in eight pointings (see Figure 3.) Each visit to the Crab will consist of 5 orbits of observation consisting of (a) three half-orbit exposures in O ILambda6300 (F631N), (b) two half-orbit exposures (i.e., a single orbit CR-SPLIT exposure) in S IILambdaLambda6717, 6731 (F673N), (c) two full orbits of exposure in O IIILambda5007, and a single half-orbit exposure in the relatively line-free F547M. The existing WFPC2 observations of the Crab show that O I and S II are good tracers of the low and intermediate ionization portions of filaments. The O III images are needed to map the high ionization envelopes around filaments, and to trace the postshock cooling region (the ``skin'') around the periphery of the remnant. Among them, these three filters capture the full range of ionization states of the gas in the Crab that is accessible using strong visible lines. The F547M exposure is needed to subtract the synchrotron emission from the line images. 12pt beginminipaget3.0in psfigfile=positions_0.epsi, width=3.0in endminipage beginminipaget3in -2.5in Figure 3. A ground based O III image of the Crab overlaid with 8 WFPC2 pointings at orientations of 265degrees\ and 85degrees. endminipage 12pt All exposure times are based on measurements of the previous sets of the HST observations of the Crab. S II is an especially strong line in the Crab, and will have the highest signal to noise of any of the observations, despite the shorter integration time. The integrated O I signal from a filament is typically down by about a factor of 5 from S II, which justifies a somewhat longer exposure on O I. However, since the O I is typically about a factor of 2 more concentrated than the more diffuse S II, the S II and O I images will have similar detection thresholds in terms of what small faint filaments can be seen in each line. O III is also a very strong line, but the WFPC2 response is lower at 5000Angstrom\ than around 6500Angstrom. The O III emission is also significantly more diffuse than the lower ionization lines. Estimates based on the existing data indicate that we should get a signal to noise of ~ 5 to 10 in a two-orbit O III image of the faint skin. The half-orbit F547M exposures will be used to subtract off the relatively smooth background of the synchrotron nebula, and so we can use an ``agressive'' cosmic ray identification algorithm to flag and remove cosmic rays in these single exposures. (In addition, the continuum map will allow us to trace the subarcsecond striations in the synchrotron nebula that delineate the magnetic topology of the remnant, allowing us to add some knowledge of the field geometry to our study of the interaction between the synchrotron nebula and the filaments. The continuum images will also allow us to complete a survey of absorption by dust on the near side of the Crab.) There are two issues worth mentioning with regard to these observations. The first is the velocity structure. Most of the proposed pointings are dominated by emission near the edge of the Crab, where filament velocity is nearly perpendicular to the line of sight. However, in the inner parts of the nebula (about 6 WFC fields of view, or the equivalent of 2 pointings) some of the emission will be Doppler shifted out of the passbands of the O I and O III filters. These pointings are still useful, however, because they allow us to look along the length of R- T fingers extending into the interior of the Crab. The heads of these R-T fingers are moving at slow enough velocities that they are seen in all filters. In addition, the broader S II filter gives almost complete coverage of the full spread of velocities in the nebula. (On the redshifted side of the nebula the Lambda6717 line remains within the filter passband, while on the blueshifted side of the nebula the Lambda6731 line is still visible.) It is worth noting here why we are not proposing to observe the Crab in HAlpha. The F656N filter is significantly narrower than the other narrow band filters to be used, and so HAlpha would fall outside the passband over a larger portion of the nebula. At the same time, Doppler shifts would move the lines of N II at 6548Angstrom\ and 6584Angstrom\ into the F656N passband around much of the remnant. The resulting complex and changing mix of lines in the image would be very difficult to interpret. The second issue involves the recently reported on-orbit deterioration in charge transfer efficiency of the WFPC2. While in principle a program like this may seem to be strongly impacted by the CTE problem, the background provided by the synchrotron nebula is adequate to alleviate this problem (which is seen primarily in observations of faint objects against zero background). Real Time Justification ----------------------- There are a number of supporting observations that have been or will be obtained. We have initiated a program of ground- based imaging and spectroscopy of the Crab in the light of Ne VLambda3426. This very high ionization line is seen predominantly behind the shock around the Crab, and is sensitive to shock velocities upwards of about 170 km/sec. These observations will provide independent constraints on shock velocity from location to location around the remnant. We have also begun a reanalysis of the Fabry-Perot observations of the Crab published by Lawrence et al. (1995). This reanalysis (which will form much of the PhD thesis of a student at ASU) is geared both toward following the structure of the O III skin (i.e., the shock) in phase space. It will also allow us to investigate the dynamical structure along the length of R-T fingers seen along our line of sight. Both of these will be of great utility in placing the results of our HST observations in a broader physical context. We should also note that these observations will be carried out during a period of intensive observation of the Crab synchrotron nebula. The observations of the Crab synchrotron nebula include a coordinated program using the HST (GO time approved during Cycle 6 but deferred due to the NICMOS problem) and the ACIS instrument on AXAF to monitor the temporal evolution of the inner part of the Crab. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 8222( 4) - 08/23/01 07:58 - [ 3] Data Distribution Paper Products: NO Media: ELECTRONIC Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 8222( 4) - 08/23/01 07:58 - [ 4] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 CRAB-FIELD-1 ISM, SNR RA= 05H 34M 22.640S +/- .010S, J2000 V = 17 DEC= +22D 00' 5.19" +/- 0.10" 2 CRAB-FIELD-2 ISM, SNR RA= 05H 34M 24.834S +/- .010S, J2000 V = 17 DEC= +22D 02' 33.29" +/- 0.10" 3 CRAB-FIELD-3 ISM, SNR RA= 05H 34M 29.593S +/- .010S, J2000 V = 17 DEC= +21D 59' 49.06" +/- 0.10" 4 CRAB-FIELD-4 ISM, SNR RA= 05H 34M 31.573S +/- .010S, J2000 V = 17 DEC= +22D 02' 12.32" +/- 0.10" 5 CRAB-FIELD-5 ISM, SNR RA= 05H 34M 39.707S +/- .010S, J2000 V = 17 DEC= +22D 01' 12.09" +/- 0.10" 6 CRAB-FIELD-6 ISM, SNR RA= 05H 34M 37.855S +/- .010S, J2000 V = 17 DEC= +21D 58' 53.67" +/- 0.10" 7 CRAB-FIELD-7 ISM, SNR RA= 05H 34M 43.367S +/- .010S, J2000 V = 17 DEC= +21D 59' 39.11" +/- 0.10" 8 CRAB-FIELD-8 ISM, SNR RA= 05H 34M 34.560S +/- .010S, J2000 V = 17 DEC= +22D 03' 49.07" +/- 0.10" 8222( 4) - 08/23/01 07:58 - [ 5] Visit: 01 Visit Priority: Visit Requirements: ORIENT 68.0D TO 68.0D On Hold Comments: Additional Comments: The purpose of this program is to construct a mosaic of the Crab Nebula with eight pointings of the WFPC2. Covering the Crab with eight pointings is difficult at best, and requires minimal overlap between pointings. This in turn drives very stringent pointing and orientation constraints. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 11 CRAB-FIELD- WFPC2 IMAGE WFALL-F F547M CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 900 S 1 IX ------------------------------------------------------------------------------------------------------------------------------------ 12 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 1300 S 1 IX ------------------------------------------------------------------------------------------------------------------------------------ 13 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 1 IX ------------------------------------------------------------------------------------------------------------------------------------ 14 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 1 IX ------------------------------------------------------------------------------------------------------------------------------------ 15 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 1 IX ------------------------------------------------------------------------------------------------------------------------------------ 16 CRAB-FIELD- WFPC2 IMAGE WFALL-F F673N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 1 IX ------------------------------------------------------------------------------------------------------------------------------------ 8222( 4) - 08/23/01 07:58 - [ 6] Visit: 02 Visit Priority: Visit Requirements: ORIENT 68.0D TO 68.0D 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 ------------------------------------------------------------------------------------------------------------------------------------ 21 CRAB-FIELD- WFPC2 IMAGE WFALL-F F547M CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 900 S 2 IX ------------------------------------------------------------------------------------------------------------------------------------ 22 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 1300 S 2 IX ------------------------------------------------------------------------------------------------------------------------------------ 23 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 2 IX ------------------------------------------------------------------------------------------------------------------------------------ 24 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 2 IX ------------------------------------------------------------------------------------------------------------------------------------ 25 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 2 IX ------------------------------------------------------------------------------------------------------------------------------------ 26 CRAB-FIELD- WFPC2 IMAGE WFALL-F F673N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 2 IX ------------------------------------------------------------------------------------------------------------------------------------ 8222( 4) - 08/23/01 07:58 - [ 7] Visit: 03 Visit Priority: Visit Requirements: ORIENT 248.0D TO 248.0D 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 ------------------------------------------------------------------------------------------------------------------------------------ 31 CRAB-FIELD- WFPC2 IMAGE WFALL-F F547M CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 900 S 3 IX ------------------------------------------------------------------------------------------------------------------------------------ 32 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 1300 S 3 IX ------------------------------------------------------------------------------------------------------------------------------------ 33 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 3 IX ------------------------------------------------------------------------------------------------------------------------------------ 34 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 3 IX ------------------------------------------------------------------------------------------------------------------------------------ 35 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 3 IX ------------------------------------------------------------------------------------------------------------------------------------ 36 CRAB-FIELD- WFPC2 IMAGE WFALL-F F673N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 3 IX ------------------------------------------------------------------------------------------------------------------------------------ 8222( 4) - 08/23/01 07:58 - [ 8] Visit: 04 Visit Priority: Visit Requirements: ORIENT 248.0D TO 248.0D 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 ------------------------------------------------------------------------------------------------------------------------------------ 41 CRAB-FIELD- WFPC2 IMAGE WFALL-F F547M CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 900 S 4 IX ------------------------------------------------------------------------------------------------------------------------------------ 42 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 1300 S 4 IX ------------------------------------------------------------------------------------------------------------------------------------ 43 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 4 IX ------------------------------------------------------------------------------------------------------------------------------------ 44 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 4 IX ------------------------------------------------------------------------------------------------------------------------------------ 45 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 4 IX ------------------------------------------------------------------------------------------------------------------------------------ 46 CRAB-FIELD- WFPC2 IMAGE WFALL-F F673N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 4 IX ------------------------------------------------------------------------------------------------------------------------------------ 8222( 4) - 08/23/01 07:58 - [ 9] Visit: 05 Visit Priority: Visit Requirements: ORIENT 68.0D TO 68.0D 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 ------------------------------------------------------------------------------------------------------------------------------------ 51 CRAB-FIELD- WFPC2 IMAGE WFALL-F F547M CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 900 S 5 IX ------------------------------------------------------------------------------------------------------------------------------------ 52 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 1300 S 5 IX ------------------------------------------------------------------------------------------------------------------------------------ 53 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 5 IX ------------------------------------------------------------------------------------------------------------------------------------ 54 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 5 IX ------------------------------------------------------------------------------------------------------------------------------------ 55 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 5 IX ------------------------------------------------------------------------------------------------------------------------------------ 56 CRAB-FIELD- WFPC2 IMAGE WFALL-F F673N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 5 IX ------------------------------------------------------------------------------------------------------------------------------------ 8222( 4) - 08/23/01 07:58 - [ 10] Visit: 06 Visit Priority: Visit Requirements: ORIENT 68.0D TO 68.0D 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 ------------------------------------------------------------------------------------------------------------------------------------ 61 CRAB-FIELD- WFPC2 IMAGE WFALL-F F547M CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 900 S 6 IX ------------------------------------------------------------------------------------------------------------------------------------ 62 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 1300 S 6 IX ------------------------------------------------------------------------------------------------------------------------------------ 63 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 6 IX ------------------------------------------------------------------------------------------------------------------------------------ 64 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 6 IX ------------------------------------------------------------------------------------------------------------------------------------ 65 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 6 IX ------------------------------------------------------------------------------------------------------------------------------------ 66 CRAB-FIELD- WFPC2 IMAGE WFALL-F F673N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 6 IX ------------------------------------------------------------------------------------------------------------------------------------ 8222( 4) - 08/23/01 07:58 - [ 11] Visit: 07 Visit Priority: Visit Requirements: ORIENT 282.0D TO 282.0D 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 ------------------------------------------------------------------------------------------------------------------------------------ 71 CRAB-FIELD- WFPC2 IMAGE WFALL-F F547M CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 900 S 7 IX ------------------------------------------------------------------------------------------------------------------------------------ 72 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 1300 S 7 IX ------------------------------------------------------------------------------------------------------------------------------------ 73 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 7 IX ------------------------------------------------------------------------------------------------------------------------------------ 74 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 7 IX ------------------------------------------------------------------------------------------------------------------------------------ 75 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 7 IX ------------------------------------------------------------------------------------------------------------------------------------ 76 CRAB-FIELD- WFPC2 IMAGE WFALL-F F673N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 7 IX ------------------------------------------------------------------------------------------------------------------------------------ 8222( 4) - 08/23/01 07:58 - [ 12] Visit: 08 Visit Priority: Visit Requirements: ORIENT 62.0D TO 62.0D 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 ------------------------------------------------------------------------------------------------------------------------------------ 81 CRAB-FIELD- WFPC2 IMAGE WFALL-F F547M CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 900 S 8 IX ------------------------------------------------------------------------------------------------------------------------------------ 82 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 1300 S 8 IX ------------------------------------------------------------------------------------------------------------------------------------ 83 CRAB-FIELD- WFPC2 IMAGE WFALL-F F631N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 8 IX ------------------------------------------------------------------------------------------------------------------------------------ 84 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 8 IX ------------------------------------------------------------------------------------------------------------------------------------ 85 CRAB-FIELD- WFPC2 IMAGE WFALL-F F502N CLOCKS=NO,CR-SPLIT=NO,ATD-GAIN=7 1 2600 S 8 IX ------------------------------------------------------------------------------------------------------------------------------------ 86 CRAB-FIELD- WFPC2 IMAGE WFALL-F F673N CLOCKS=NO,CR-SPLIT=0.5,ATD-GAIN=7 1 2600 S 8 IX ------------------------------------------------------------------------------------------------------------------------------------ 8222( 4) - 08/23/01 07:58 - [ 13] Summary Form for Proposal 8222 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures WFALL-FIX ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CLOCKS=NO CR-SPLIT=NO ATD-GAIN=7 CR-SPLIT=0.5 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 68.0D TO 68.0D ORIENT 248.0D TO 248.0D ORIENT 282.0D TO 282.0D ORIENT 62.0D TO 62.0D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F547M F631N F502N F673N ------------------------------------------------------------------------------------------------------------------------------------ Target Names CRAB-FIELD-1 CRAB-FIELD-2 CRAB-FIELD-3 CRAB-FIELD-4 CRAB-FIELD-5 CRAB-FIELD-6 CRAB-FIELD-7 CRAB-FIELD-8 ------------------------------------------------------------------------------------------------------------------------------------