! Proposal 6631, submission 1 ! PI: Paul Francis ! Received Tue Feb 20 05:48:23 EST 1996 ! From: pfrancis@isis.ph.unimelb.edu.au ! +====================+ ! | PED OUTPUT PRODUCT | ! +====================+ ! ! /home/pfrancis/hst_dir/phase2_dir/proposal/6631.prop ! Generated by PREPROCESSOR, version 6.0e ! Date: Tue Feb 20 21:20:11 EST 1996 Proposal_Information Title: Imaging a Cluster of Galaxies at Redshift 2.38 Proposal_Category: GO Scientific_Category: COSMOLOGY Cycle: 6 Investigators PI_Name: Paul Francis PI_Institution: University of Melbourne CoI_Name: Bruce Woodgate CoI_Institution: NASA Goddard Space-Flight Center Contact: Abstract: We have discovered ~ 8 galaxies at redshift 2.38, forming what we believe to be a rich galaxy cluster in the early stages of formation. A sub-set of ~ 4 galaxies within the cluster form a very compact (< 100 kpc) galaxy group and may be merging to form a giant elliptical galaxy. This proto- elliptical is embedded in an extended, Ly-Alpha emitting, lumpy cloud of gas and dust, which is probably responsible for a complex of Lyman-limit absorption systems in the spectrum of a background QSO. We propose to image the cluster both in broad-band colours and in Ly-Alpha. These images will allow us to search for compact starbursts, which we hypothesise are responsible for the presence of dust in the extended gaseous cloud surrounding the proto-elliptical. The detailed morphology of the Ly-Alpha emission will tell us about the distribution of dust and gas, and their interaction with the stellar population. The colours, sizes and morphologies of the galaxies will give us a picture of new-born cluster ellipticals. Questions Observing_Description: We propose to observe though the F410 filter for 24 orbits. This filter is 147 Angstrom wide and its peak transmission wavelength closely matches the wavelength of Ly-Alpha in this cluster (~ 4113 Angstrom). Orbital visibility at this declination is 55 minutes, which allowing for acquisition and overheads gives 44 or 46 minutes exposure on target per orbit. No CR-split will be required, as CR rejection can be done by using frames taken in different orbits. WFPC2's field of view is sufficient to observe all our galaxies simultaneously. Due to its lower read noise, the FOC would be marginally more sensitive through the F410 filter. However, its field of view is too small to observe all our galaxies simultaneously, and we believe the advantage of observing ten galaxies simultaneously to outweigh the slight sensitivity disadvantage. We plan to be sensitive to line fluxes of > 10^ -17 ergs cm^-2 s^-1 from unresolved sources. A source with this flux will yield 3.4 * 10^-3 counts per second. Sky counts will be low (1.6 * 10^-3 counts per second per pixel). For an unresolved source, read-out noise and poisson noise will be comparable, and a 5 Sigma detection will require ~ 24 orbits. Our sensitivity will decrease for more extended sources, becoming comparable to the limiting narrow-band magnitudes obtainable with ground-based 4-m telescopes on scales of ~ 0.7". The depth of the off-band comparison image (F450) determines the equivalent width sensitivity limit on our Ly-Alpha search. Limits of below 50 Angstrom are not sensible, as confusion with foreground O II emission dominates, and confirming spectroscopy will probably be impossible at these faint limits. An off-band limiting magnitude of ~ 29 for unresolved sources gives an equivalent- width limit of 50 Angstrom (given the relative transmission and width of F410 and F450), and will require ~ 8 orbits. The broad-band observations are sky limited, so the low-sky constraint is needed; this only reduced exposure times by ~ 5%, as most of the high-sky period is taken up by overheads. We choose F450 as our off-band because of its sensitivity. Its centroid lies somewhat to the red of F410's centroid, but our F702 observations should allow us to make the slight necessary colour correction. We also plan to obtain 6 orbits with the wide R filter, F702. This will allow us to measure continuum colours for our galaxies and for any star formation regions identified. With 6 orbits we will reach a limiting magnitude of R ~ 28 for compact objects. The F450 and F702 exposures are chosen to match the sensitivity of the Ly-Alpha search for compact star formation regions. Using the models of Charlot & Fall (1993, in `First Light in the Universe', ed Rocca Volmerange et al. p 341), Bruzual & Charlot (1993, ApJ 405, 538) and Arimoto et al. (1987, A& A 173, 23 and 1992, A& A 253, 21), a compact dust-free starbursting region of stellar mass 10^8 M_SUN will emit roughly our limiting Ly- Alpha flux, and have B ~ 29 and R ~ 28, our limiting F450 and F702 magnitudes for compact objects. This would correspond to a star formation rate of ~ 0.3 M_sun yr^-1. This choice of a limiting sensitivity was guided by the experience of Windhorst et al. (1995, private communication), and is about a factor of five deeper than the limiting magnitude of ground -based 4-m class telescopes (this field is too far south for Keck). Given the surface brightnesses measured from the ground for the centre of B1 and for B2, these integration times should give us enough photons per resolution element to generate maps with significant information on scales matching HST's resolution. In Oct 95 at the AAT we obtained Ly-alpha imaging of a larger field surrounding the group, identifying several more probable Ly-alpha galaxies. By judicious choice of orientation and pointing, it is possible to include two of these new galaxy candidates in the WFPC-2 field of view. Real_Time_Justification: Our Ly-Alpha galaxies were first detected in two nights of narrow-band imaging on the CTIO 4-m telescope. We have been awarded three nights on the AAT and one night on the CTIO 4-m in October 1995 for further narrow band imaging, in which we will extend our field to view to cover the whole absorption- line supercluster and push our sensitivity to the theoretical limiting magnitude of 4-m telescopes, using a purpose built narrow-band filter at prime focus. We have broad-band optical colours obtained during two nights on the ESO 3.6-m telescope. We have been scheduled AAT and CTIO 4-m time to push our optical broad-band images to the limiting magnitudes of the telescopes. We have had four nights of spectroscopy on our galaxies, two with the ESO NTT, and one each with the AAT and CTIO 4-m, which has confirmed the Ly-Alpha detections and detected CIV in B1. We have another two nights of spectroscopy on the AAT scheduled in late September 1995. We have a high resolution spectrum of the background QSO obtained in 4 nights on the AAT. We have had five nights of near-IR imaging with the Siding Spring 2.3-m telescope, and two with the ESO 2.2-m telescope. Results include detecting our galaxies in the H and K bands, and a narrow-band H-Alpha detection of B1. We have mapped our field at 1344 and 2378 MHz with the compact array of the Australia Telescope, 20 hours integration in both. We also have a map at 847 MHz from Molonglo. Future plans include mm-wave observations in search of redshifted CO emission, and possibly Sunyaev-Zel'dovich measurements of the cluster gas. The lack of a strong radio sources in the field make it an ideal test-bed for sensitive radio observations. Calibration_Justification: Additional_Comments: Fixed_Targets Target_Number: 1 Target_Name: GAL-CLUS-2142-4420 Alternate_Names: Description: CLUSTER OF GALAXIES,HIGH REDSHIFT CLUSTER,GROUP,EMISSION LINE NEBULA, Position: RA=21H 39M 15.546S +/- 2",DEC=-44D 33' 56.14" +/- 2" Equinox: B1950 RV_or_Z: Z = 2.38 RA_PM: 0. Dec_PM: 0. Epoch: B1950 Annual_Parallax: 0. Flux: F-LINE(4112)=8+/-1e-16 B = 24.5+/-0.5 Comments: The position is roughly in the centre of a group of candidate galaxies, and is chosen to maximise the number lying within the WFPC-2 field of view, assuming a particular orientation angle, and to place the brightest galaxies centrally on WF3. Solar_System_Targets Generic_Targets Scan_Data Visits Visit_Number: 01 Visit_Requirements: ORIENT 348D TO 060D On_Hold_Comments: Visit_Comments: Angle and position chosen to maximise number of galaxy candidates within the field. Check that the primary galaxy does not fall on a bad part of the chip. One of three identical visits, all of which should use the same guide stars. Exposure_Number: 1 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.0,0.0 MAX DUR 150% EXPAND Comments: Exposure_Number: 2 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.0,0.0 MAX DUR 150% EXPAND Comments: Exposure_Number: 3 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.5,0.25 MAX DUR 150% EXPAND Comments: Exposure_Number: 4 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.5,0.25 MAX DUR 150% EXPAND Comments: Exposure_Number: 5 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.75,0.75 MAX DUR 150% EXPAND Comments: Exposure_Number: 6 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.75,0.75 MAX DUR 150% EXPAND Comments: Exposure_Number: 7 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.25,0.5 MAX DUR 150% EXPAND Comments: Exposure_Number: 8 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.25,0.5 MAX DUR 150% EXPAND Comments: Visit_Number: 02 Visit_Requirements: SAME ORIENT AS 01 On_Hold_Comments: Visit_Comments: Angle and position chosen to maximise number of galaxy candidates within the field. Check that the primary galaxy does not fall on a bad part of the chip. One of three identical visits, all of which should use the same guide stars. Exposure_Number: 1 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.0,0.0 MAX DUR 150% EXPAND Comments: Exposure_Number: 2 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.0,0.0 MAX DUR 150% EXPAND Comments: Exposure_Number: 3 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.5,0.25 MAX DUR 150% EXPAND Comments: Exposure_Number: 4 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.5,0.25 MAX DUR 150% EXPAND Comments: Exposure_Number: 5 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.75,0.75 MAX DUR 150% EXPAND Comments: Exposure_Number: 6 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.75,0.75 MAX DUR 150% EXPAND Comments: Exposure_Number: 7 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.25,0.5 MAX DUR 150% EXPAND Comments: Exposure_Number: 8 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.25,0.5 MAX DUR 150% EXPAND Comments: Visit_Number: 03 Visit_Requirements: SAME ORIENT AS 01 On_Hold_Comments: Visit_Comments: Angle and position chosen to maximise number of galaxy candidates within the field. Check that the primary galaxy does not fall on a bad part of the chip. One of three identical visits, all of which should use the same guide stars. Exposure_Number: 1 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.0,0.0 MAX DUR 150% EXPAND Comments: Exposure_Number: 2 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.0,0.0 MAX DUR 150% EXPAND Comments: Exposure_Number: 3 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.5,0.25 MAX DUR 150% EXPAND Comments: Exposure_Number: 4 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.5,0.25 MAX DUR 150% EXPAND Comments: Exposure_Number: 5 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.75,0.75 MAX DUR 150% EXPAND Comments: Exposure_Number: 6 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.75,0.75 MAX DUR 150% EXPAND Comments: Exposure_Number: 7 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.25,0.5 MAX DUR 150% EXPAND Comments: Exposure_Number: 8 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F410M Wavelength: Optional_Parameters: ATD-GAIN=7,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 40M Special_Requirements: POS TARG 0.25,0.5 MAX DUR 150% EXPAND Comments: Visit_Number: 04 Visit_Requirements: SAME ORIENT AS 01 On_Hold_Comments: Visit_Comments: Exposure_Number: 1 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F450W Wavelength: Optional_Parameters: ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 120S Special_Requirements: POS TARG 0.0,0.0 Comments: exposures 1 and 2 should be first in orbit, to avoid saturation Exposure_Number: 2 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F450W Wavelength: Optional_Parameters: ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 120S Special_Requirements: POS TARG 0.0,0.0 Comments: exposures 1 and 2 should be 1st in orbit, to avoid saturation Exposure_Number: 3 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F450W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 25M Special_Requirements: LOW-SKY POS TARG 0.0,0.0 MAX DUR 200% EXPAND Comments: Exposure_Number: 4 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F450W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.0,0.0 MAX DUR 150% EXPAND Comments: Exposure_Number: 5 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F450W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.0,0.0 MAX DUR 150% EXPAND Comments: Exposure_Number: 6 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F450W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.0,0.0 MAX DUR 150% EXPAND Comments: Exposure_Number: 7 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F450W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.5,-0.25 MAX DUR 150% EXPAND Comments: Exposure_Number: 8 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F450W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.5,-0.25 MAX DUR 150% EXPAND Comments: Exposure_Number: 9 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F450W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.5,-0.25 MAX DUR 150% EXPAND Comments: Exposure_Number: 10 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F450W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.5,-0.25 MAX DUR 150% EXPAND Comments: Visit_Number: 05 Visit_Requirements: SAME ORIENT AS 01 On_Hold_Comments: Visit_Comments: Exposure_Number: 1 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F702W Wavelength: Optional_Parameters: ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 60S Special_Requirements: POS TARG 0.0,0.0 Comments: exposures 1 and 2 should be first in visit, to avoid saturation Exposure_Number: 2 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F702W Wavelength: Optional_Parameters: ATD-GAIN=15,CR-SPLIT=NO Number_of_Iterations: 1 Time_Per_Exposure: 60S Special_Requirements: POS TARG 0.0,0.0 Comments: exposures 1 and 2 should be first in visit, to avoid saturation Exposure_Number: 3 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F702W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 25M Special_Requirements: LOW-SKY POS TARG 0.0,0.0 MAX DUR 200% EXPAND Comments: Exposure_Number: 4 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F702W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.0,0.0 MAX DUR 150% EXPAND Comments: Exposure_Number: 5 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F702W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.0,0.0 MAX DUR 150% EXPAND Comments: Exposure_Number: 6 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F702W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.5,-0.25 MAX DUR 150% EXPAND Comments: Exposure_Number: 7 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F702W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.5,-0.25 MAX DUR 150% EXPAND Comments: Exposure_Number: 8 Target_Name: GAL-CLUS-2142-4420 Config: WFPC2 Opmode: IMAGE Aperture: WF3-FIX Sp_Element: F702W Wavelength: Optional_Parameters: CR-SPLIT=NO,ATD-GAIN=7 Number_of_Iterations: 1 Time_Per_Exposure: 35M Special_Requirements: LOW-SKY POS TARG 0.5,-0.25 MAX DUR 150% EXPAND Comments: Data_Distribution ! Defaults indicated; change if desired Medium: 8MM Blocking_Factor: 10 Ship_To: PI_Address Ship_Via: UPS Recipient_Email: ! Let us know what you think of this template and software! ! Please send a list of your likes and dislikes to your Program Coordinator