7861( 8) - 03/05/98 16:27 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 7861 Version: 8 Check-in Date: 05-Mar-1998 16:24:52 1.Proposal Title: A Search for Extrasolar Giant Planets in the Nearby TW Hya Association ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 7 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: DAVID WEINTRAUB VANDERBILT UNIVERSITY CoI: Didier Saumon Vanderbilt University N CoI: Joel Kastner Massachusetts Institute of Technology N CoI: Thierry Forveille Observatoire de Grenoble N ------------------------------------------------------------------------------------ 5. Abstract One of the primary goals of NASA's mission is the identification of formed and nascent planetary systems. As the nature of giant planets is to cool off quickly as they age, the best stars around which to search for extrasolar giant planets (EGPs) are nearby pre-main sequence (PMS) stars. In this proposal, we identify a unique opportunity for pursuing these goals: we have identified a cluster of five T Tauri stars (TTS) only 39-60 pc from Earth. These stars are at least three times closer than any previously identified TTS. We request time to carry out a three-filter (F164N, F190N, F215N) observing program designed to detect EGPs and brown dwarfs (BDs) around four of these stars by comparison of the observations with model predictions of H_2 absorption in the atmospheres of cool, gaseous objects. Because these stars are only ~20 MY old, any associated EGPs and BDs intrinsically will be 3^m-6^m brighter than similar objects of ages 0.1-1.0 Gyr (e.g., those in the Pleiades or Hyades clusters); and by virtue of the proximity of these stars, such objects will be brighter by ~3^m in comparision to young EGPs and BDs in the next closest clusters of PMS stars. In addition, by virtue of their proximity, we have the unprecedented opportunity to image substellar objects within 20 AU of these TTS. This is the region of space not accessible to the GTO programs of coronagraphic imaging of three of these stars yet it is an accessible region for these stars and is a region of fundamental importance for planetary formation. ------------------------------------------------------------------------------------ 7861( 8) - 03/05/98 16:27 - [ 2] Observations Description ------------------------ Our proposed observing program for each target star using NIC1 and NIC2 is very straightforward. After target acquisition using NIC1, we obtain two long exposures, one each with the F164N and F190N filters. We then switch to NIC2 and obtain a F215N observation. NICMOS instrument performance indicates that the thermal background is extremely low in the F164N and F190N bands; thus, we should not need thermal background images for calibration except in the 2.15 Mum window. To remove the thermal background from the F215N images, we will use the ONE-CHOP observing pattern with a chop size smaller than the field of view (keeping the target on-chip at both positions). NIC1 has a pixel size of ptsec043 and a field of view of 11ptsec0 * 11ptsec0. NIC2 has larger pixels (0ptsec075) and a larger field of view (19ptsec2 * 19ptsec2). More than 90 source is expected to fall within a 0ptsec3 (7 px) radius, more than 50 of the light within a 0ptsec1 (2 px) radius. Thus with NIC1, for the TW Hya Association stars, after subtracting the point spread function (PSF) of the primary, we will be able to image secondary objects as close as ~5 AU from the primaries. As seen in the data in Table 2, BD companions could be only 2-3 magnitudes fainter than the primary and thus could be easy to pick out, even in the region from 0 ptsec05 -- 0ptsec4 of the primary, where they are most likely to exist. For fainter EGP and BD companions, we will need to subtract the PSF of the primary in order to complete our analysis of these images. We have selected HD 106965 as a point source comparison star to image through each filter in order to obtain a PSF well matched in time, and therefore in any systemic effects, to our target stars. HD 106965 is an A2 star used as an ``A+'' quality infrared photometric standard for many years (Elias et al. 1982). It is also possible that the IDT will have an appropriate set of PSF observations that can be made available to us without assigning this orbit to our program. We have chosen the filters for the following reasons. Model BD spectra (Marley, Saumon et al. 1996) show strong absorption due to H_2O in a band centered at ~1.9 Mum. The drop in this absorption band can be as much as two orders of magnitude below the continuum level. Indeed, in the observed spectrum of Gl 229B (Oppenheimer et al. 1995; Geballe et al. 1996), a drop is seen that is fully one order of magnitude across this band. In contrast, in the spectral region from 1.55 - 1.75 and 2.0 - 2.2 Mum, the fluxes from a cool (T < 1500 K) source would be at relative maxima. In comparison, stellar objects with photospheric temperatures above 3500 K will have no H_2O in their atmospheres and will show more nearly featureless continua. Stellar objects with temperatures from 2000 to 3500 K also can show some H_2O absorption at 1.9 Mum, for example, LHS 2924, a dM9 star with T = 2100-2200 K shows an absorption drop of about 20 the TW Hya Association stars which are ~20 MY old, it is important to recognize that young, low mass stars will be significantly warmer than old, low mass stars. According to the models of Burrows et al(1997), objects with masses above 0.08 M_odot will retain temperatures above 3000 K until they are more than 100 MY old; in fact, BDs with masses above 0.02 M_odot will be only marginally cooler than the lowest mass young stars because of the effect of deuterium burning. This means that any absorption due to H_2O in the atmosphere of a young stellar object or BD in the mass range of 0.02 - 0.08 M_odot will be very small due to the elevated photospheric temperatures of young objects vs. old objects, whereas the 1.9 Mum absorption feature toward cool EGPs and the lowest mass BDs will be quite large. We will clearly be able to identify objects in the mass range below 0.02 M_odot as substellar. Objects that show a small amount of H_2O absorption will be identifiable immediately only as ``cool,'' not as ``low mass.'' However, given the small field of view of NICMOS, and the high galactic latitudes of our target stars, giant stars would need to be at extragalactic distances to cause confusion; thus, the probability of finding unrelated cool objects within 0ptsec4 of these stars will be quite small. Where appropriate, follow-up observations using proper motion, absolute luminosity, and lithium absorption line measurements could be employed to determine definitively whether such objects were distant red giants, nearby low mass stars or BDs. Because the TW Hya Association stars are bright X-ray sources, and because the X-ray luminosities of these stars may generate fluorescence in the ro-vibrational band 2.12 Mum of molecular hydrogen in circumstellar gas (Tine et al. 1997), we must use a narrow band filter that avoids contamination from possible molecular hydrogen emission at 2.12 mum. Thus, the F164N, F190N and F215N are nearly optimally designed as ``on,'' ``off,'' and ``on'' narrow band filters for this deep water band and thus should provide a very effective method for discriminating between sources with warm (T > 2500 K) and cool (T < 1500 K) atmospheres. Any objects detected that show steep drops in flux in the F190N filter followed by a rise back up in the F215N band and which have continuum level fluxes consistent with those expected for substellar mass companions are very likely EGPs or BDs. The expected magnitudes of our primary stars are 7.9-8.0 at H band. In comparison, the broad band H magnitudes of EGPs and BDs around these stars would range from 10.2 to 14.5, depending on the mass of the object: beginenumerate itemTW Hya has an observed K magnitude of 7.37 and a spectral type of K7V, for which we predict an H magnitude of ~7.9. itemCD- 29^degrees8887 has an observed V = 11.1 and a spectral type of M0V, for which we predict an K magnitude of ~7.5 and H magnitude of ~ 8.0. itemCD-33^degrees7795 has an observed V = 11.4 and a spectral type of M1V, for which we predict an K magnitude of ~7.4 and H magnitude of ~ 7.9. itemHen(3) 600 is a 1 ptsec5 visual binary (DeltaV~ 0.5^m) with a combined V = 12.04 and V-I = 2.93 and spectral types of M3 assigned to both (de la Reza et al. 1989). From these magnitudes and spectral types, we predict H ~eq 8.0 and K ~eq 7.4. endenumerate The H band magnitudes of the primaries (~8) correspond to expected flux densities ~1.5 Jy while the H band magnitudes of the EGPs and BDs (10.2 to 14.5) correspond to expected flux densities of 1.5 to 77 mJy. The K band magnitudes of the primaries (~7.4) correspond to expected flux densities of ~ 0.5 Jy while the K band magnitudes of the EGPs and BDs (11.0 to 14.2) correspond to expected flux densities of 1.5 to 29 mJy (NICMOS Units Conversion Tool). We have used the NICMOS Simulation software to estimate saturation times and expected signal-to-noise ratios (SNRs) for our program goals. In Table 3 we list the maximum integration times possible without saturation of the detector with each of the three filters as a function of the brightness of the primary stars. It is important that we not saturate the primary so that we can carefully subtract the PSF of the primary from our images. Therefore, during Phase II, we will work with the STScI support staff to determine maximum exposure times, in order to improve the sensitivity in the rest of the field, without saturating the primary. begincenter Table 3: Maximum Possible Integration Times, begintabularrr Filter & Time, F164N & 72 s, F190N & 100 s, F215N & 30 s, endtabular endcenter Next (Table 4), we estimate the SNRs we would obtain in these integration times for the range of apparent magnitudes predicted for 10-100 M_ J objects around our target stars. For the F190N filter, we assume a range of continuum levels from 1.5 to 50 mJy and we then assume we need to make a detection at a flux level that is 20 begincenter Table 4: Predicted Signal-to-Noise Ratios, begintabularrrrr Filter & SNR (if F = 77 mJy) & SNR (if F = 1.5 mJy) , F164N (72 s) & 152 & 13 , , & SNR (if F = 40 mJy) & SNR (if F = 1.2 mJy) , F190N (100 s) & 115 & 12 , , & SNR (if F = 29 mJy) & SNR (if F = 1.5 mJy) , F215N (30 s) & 100 & 14 , endtabular endcenter The exposures will be obtained using MULTIACCUM exposure time sequences. We estimate ~8 minutes for guide star acquisition at the beginning of each orbit. Only 12 s are needed for instrument set-up for each filter and switching from NIC1 to NIC2 while pointed at a single target involves minimal overheads. Thus, we estimate we will have of order 45 minutes (2700 s) for observing per orbit, of which one-third to one-half will be lost to system overheads, leaving ~1300 s of actual on-source integration time per orbit. Therefore we plan ~450 s on- source observing time in each of the three filters for each of the four target stars. We will repeat the longest non- saturating MULTIACCUM observations 5-20 times, depending on the target brightness, so as to obtain the greatest possible SNR on our faintest possible EGP candidates. For each source, we will acquire our target using NIC1, observe with F164N and F190N, and then switch to NIC2 and F215N. With NIC2, we will carry out a two position (ONE-CHOP) patterned observation program in order to obtain thermal background measurements to remove from the F215N target measurements. Our intent is to carry out in-field chopping (with the target on two different parts of the field). This somewhat reduces our field of view (which should not be a problem for this experiment) but permits us to spend all our observing time on source. Real Time Justification ----------------------- None. None. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 7861( 8) - 03/05/98 16:27 - [ 3] Data Distribution Media: ELECTRONIC Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 7861( 8) - 03/05/98 16:27 - [ 4] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 CD-298887 STAR,T TAURI STAR RA=11H 9M 13.93S +/- 0.4",DEC=- J2000 V = 12.09+/-0.16 30D 1' 38.5" +/- 0.4",PLATE- K = 7.5 ID=04JC H = 8.0 Comments: Coordinates from GSC 11 TWHYA STAR,T TAURI STAR RA=11H 1M 51.95S +/- 0.4",DEC=- J2000 V = 12.11+/-0.41 34D 42' 17.7" +/- 0.4",PLATE- K = 7.37 ID=0482 H = 7.9 Comments: Coordinates from GSC 21 HEN3-600 STAR,T TAURI STAR RA=11H 10M 27.98S +/- 0.4",DEC=- J2000 V = 12.93+/-0.43 37D 31' 52.5" +/- 0.4",PLATE- K = 7.4 ID=04HE H = 8.0 Comments: Coordinates from GSC 31 CD-337795 STAR,T TAURI STAR RA=11H 31M 55.42S +/- 0.4",DEC=- J2000 V = 12.55+/-0.35 34D 36' 27.4" +/- 0.4",PLATE- K = 7.4 ID=00JJ H = 7.9 Comments: Coordinates from GSC 41 USNO-21 STAR,M V-IV RA=11H 32M 41.44S +/- 0.1",DEC=- J2000 H = 7.74+/-0.05 26D 51' 55.81" +/- 0.1", PLATE- V = 11.7+/-0.2 ID=02ME TYPE=M3V Comments: Switched calibrator star from HD75223 to USNO-21 at PI's request. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1976.41 0.0 0.0 0.0 7861( 8) - 03/05/98 16:27 - [ 5] Visit: 01 Visit Priority: Visit Requirements: GROUP 01-05 WITHIN 60 DAYS 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 CD-298887 NIC1 MULTIAC NIC1 F164N PATTERN=SPIRAL-DITH,NUM-POS=4, 3 DEF POS TARG -1.3063,-1.3716 CUM OFFSET=SAM,DITH-SIZE=1.75, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=20 Comments: 4 positions of 34s (total=408s) 40.5 px dither size in X (0.0432025 "/pix), 40.67 px dither size in Y (0.0430282 "/pix) ------------------------------------------------------------------------------------------------------------------------------------ 20 CD-298887 NIC1 MULTIAC NIC1 F190N PATTERN=SPIRAL-DITH,NUM-POS=4, 3 DEF POS TARG -1.3063,-1.3716 CUM OFFSET=SAM,DITH-SIZE=1.75, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=25 Comments: 4 positions of 44s (total=528s) ------------------------------------------------------------------------------------------------------------------------------------ 30 CD-298887 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -1.5188,-1.5188 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 Comments: 4 positions of 16s (total=64s) 40.5 px dither size (0.075 "/pix) ------------------------------------------------------------------------------------------------------------------------------------ 31 CD-298887 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -0.8063,-0.08063 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 Comments: changing POS TARG for 215N exposures will permit better median filtering of images for sky subtraction ------------------------------------------------------------------------------------------------------------------------------------ 32 CD-298887 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -2.3063,-2.3063 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 ------------------------------------------------------------------------------------------------------------------------------------ 7861( 8) - 03/05/98 16:27 - [ 6] Visit: 02 Visit Priority: Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 TWHYA NIC1 MULTIAC NIC1 F164N PATTERN=SPIRAL-DITH,NUM-POS=4, 3 DEF POS TARG -1.3063,-1.3716 CUM OFFSET=SAM,DITH-SIZE=1.75, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=20 Comments: 4 positions of 34s (total=408s) 40.5 px dither size in X (0.0432025 "/pix), 40.67 px dither size in Y (0.0430282 "/pix) ------------------------------------------------------------------------------------------------------------------------------------ 20 TWHYA NIC1 MULTIAC NIC1 F190N PATTERN=SPIRAL-DITH,NUM-POS=4, 3 DEF POS TARG -1.3063,-1.3716 CUM OFFSET=SAM,DITH-SIZE=1.75, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=25 Comments: 4 positions of 44s (total=528s) ------------------------------------------------------------------------------------------------------------------------------------ 30 TWHYA NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -1.5188,-1.5188 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 Comments: 40.5 px dither size (0.075 "/pix) ------------------------------------------------------------------------------------------------------------------------------------ 31 TWHYA NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -0.8063,-0.08063 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 Comments: changing POS TARG for 215N exposures will permit better median filtering of images for sky subtraction ------------------------------------------------------------------------------------------------------------------------------------ 32 TWHYA NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -2.3063,-2.3063 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 ------------------------------------------------------------------------------------------------------------------------------------ 7861( 8) - 03/05/98 16:27 - [ 7] Visit: 03 Visit Priority: Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 HEN3-600 NIC1 MULTIAC NIC1 F164N PATTERN=SPIRAL-DITH,NUM-POS=4, 3 DEF POS TARG -1.3063,-1.3716 CUM OFFSET=SAM,DITH-SIZE=2.2588, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=20 Comments: 4 positions of 34s (total=408s) DITH-SIZE is 52.5 px (and 1.5 times the separation of the Hen3-600 binary) ------------------------------------------------------------------------------------------------------------------------------------ 20 HEN3-600 NIC1 MULTIAC NIC1 F190N PATTERN=SPIRAL-DITH,NUM-POS=4, 3 DEF POS TARG -1.3063,-1.3716 CUM OFFSET=SAM,DITH-SIZE=2.2588, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=25 Comments: 4 positions of 44s (total=528s) ------------------------------------------------------------------------------------------------------------------------------------ 30 HEN3-600 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -1.5188,-1.5188 CUM OFFSET=SAM,DITH-SIZE=2.6625, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 Comments: 35.5 px dither size (0.075 "/pix) os as not to be exactly twice binary separation ------------------------------------------------------------------------------------------------------------------------------------ 31 HEN3-600 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -1.125,-1.125 NO CUM OFFSET=SAM,DITH-SIZE=3.0375, SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 Comments: changing POS TARG for 215N exposures will permit better median filtering of images for sky subtraction ------------------------------------------------------------------------------------------------------------------------------------ 32 HEN3-600 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -2.25,-2.25 NO CUM OFFSET=SAM,DITH-SIZE=3.0375, SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 ------------------------------------------------------------------------------------------------------------------------------------ 7861( 8) - 03/05/98 16:27 - [ 8] Visit: 04 Visit Priority: Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 CD-337795 NIC1 MULTIAC NIC1 F164N PATTERN=SPIRAL-DITH,NUM-POS=4, 3 DEF POS TARG -1.3063,-1.3716 CUM OFFSET=SAM,DITH-SIZE=1.75, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=20 Comments: 4 positions of 34s (total=408s) 40.5 px dither size in X (0.0432025 "/pix), 40.67 px dither size in Y (0.0430282 "/pix) ------------------------------------------------------------------------------------------------------------------------------------ 20 CD-337795 NIC1 MULTIAC NIC1 F190N PATTERN=SPIRAL-DITH,NUM-POS=4, 3 DEF POS TARG -1.3063,-1.3716 CUM OFFSET=SAM,DITH-SIZE=1.75, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=25 Comments: 4 positions of 44s (total=528s) ------------------------------------------------------------------------------------------------------------------------------------ 30 CD-337795 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -1.5188,-1.5188 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 Comments: 40.5 px dither size (0.075 "/pix) ------------------------------------------------------------------------------------------------------------------------------------ 31 CD-337795 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -0.8063,-0.08063 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 Comments: changing POS TARG for 215N exposures will permit better median filtering of images for sky subtraction ------------------------------------------------------------------------------------------------------------------------------------ 32 CD-337795 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -2.3063,-2.3063 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 ------------------------------------------------------------------------------------------------------------------------------------ 7861( 8) - 03/05/98 16:27 - [ 9] Visit: 05 Visit Priority: Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 USNO-21 NIC1 MULTIAC NIC1 F164N PATTERN=SPIRAL-DITH,NUM-POS=4, 3 DEF POS TARG -1.3063,-1.3716 CUM OFFSET=SAM,DITH-SIZE=1.75, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=20 Comments: 4 positions of 34s (total=408s) 40.5 px dither size in X (0.0432025 "/pix), 40.67 px dither size in Y (0.0430282 "/pix) ------------------------------------------------------------------------------------------------------------------------------------ 20 USNO-21 NIC1 MULTIAC NIC1 F190N PATTERN=SPIRAL-DITH,NUM-POS=4, 3 DEF POS TARG -1.3063,-1.3716 CUM OFFSET=SAM,DITH-SIZE=1.75, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=25 Comments: 4 positions of 44s (total=528s) ------------------------------------------------------------------------------------------------------------------------------------ 30 USNO-21 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -1.5188,-1.5188 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 Comments: 40.5 px dither size (0.075 "/pix) ------------------------------------------------------------------------------------------------------------------------------------ 31 USNO-21 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -0.8063,-0.08063 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 Comments: changing POS TARG for 215N exposures will permit better median filtering of images for sky subtraction ------------------------------------------------------------------------------------------------------------------------------------ 32 USNO-21 NIC2 MULTIAC NIC2 F215N PATTERN=SPIRAL-DITH,NUM-POS=4, 1 DEF POS TARG -2.3063,-2.3063 CUM OFFSET=SAM,DITH-SIZE=3.0375, NO SPLIT PATTERN-ORIENT=DETECTOR, SAMP-SEQ=STEP2,NSAMP=11 ------------------------------------------------------------------------------------------------------------------------------------ 7861( 8) - 03/05/98 16:27 - [ 10] Summary Form for Proposal 7861 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations NIC1 NIC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters PATTERN=SPIRAL-DITH NUM-POS=4 OFFSET=SAM DITH-SIZE=1.75 PATTERN-ORIENT=DETECTOR SAMP-SEQ=STEP2 NSAMP=20 NSAMP=25 NSAMP=11 DITH-SIZE=3.0375 DITH-SIZE=2.2588 DITH-SIZE=2.6625 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GROUP 01-05 WITHIN 60 DAYS POS TARG -1.3063,-1.3716 NO SPLIT POS TARG -1.5188,-1.5188 NO SPLIT POS TARG -0.8063,-0.08063 NO SPLIT POS TARG -2.3063,-2.3063 NO SPLIT POS TARG -1.125,-1.125 NO SPLIT POS TARG -2.25,-2.25 NO SPLIT ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F164N F190N F215N ------------------------------------------------------------------------------------------------------------------------------------ Target Names CD-298887 TWHYA HEN3-600 CD-337795 USNO-21 ------------------------------------------------------------------------------------------------------------------------------------