! Hubble Space Telescope Cycle 5 (1995) Phase II Proposal Template ! $Id: 5971,v 4.1 1995/04/21 19:16:02 pepsa Exp $ ! ! Refer to the HST Phase II Proposal Instructions to fill this out ! ! Anything after a "!" is ignored, and may be deleted ! ! All keywords with multiple entries are comma delimited except the ! Visit_Requirements and Special_Requirements keywords which can be ! delimited with carriage returns or semi-colons, but not commas ! ! For help call your Program Coordinator: Doug Van Orsow ! Phone: 410 338-4568 , E-mail: vanorsow@stsci.edu ! ! This partially completed template was generated from a Phase I proposal. ! Name of Phase I Proposal: griffiths-915.prop ! Date generated: Sun Dec 18 09:52:02 EST 1994 ! Proposal_Information ! Section 4 Title: HST MEDIUM DEEP SURVEY Proposal_Category: GO Scientific_Category: Galaxies & Clusters Cycle: 5 Investigators PI_name: Richard Griffiths PI_Institution: Johns Hopkins University CoI_Name: Richard Ellis CoI_Institution: Institute of Astronomy, U. Cambridge Contact: ! Y or N (designate at most one contact) CoI_Name: Gerard Gilmore CoI_Institution: Institute of Astronomy, U. Cambridge Contact: ! Y or N (designate at most one contact) CoI_Name: Richard Green CoI_Institution: NOAO Contact: ! Y or N (designate at most one contact) CoI_Name: John Huchra CoI_Institution: Harvard-Smithsonian CfA Contact: ! Y or N (designate at most one contact) CoI_Name: Kavan Ratnatunga CoI_Institution: Johns Hopkins Univ. Contact: ! Y or N (designate at most one contact) CoI_Name: J. Anthony Tyson CoI_Institution: AT&T Bell Labs. Contact: ! Y or N (designate at most one contact) CoI_Name: Rogier Windhorst CoI_Institution: Arizona State Univ. Contact: ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) We have shown that randomly-positioned parallel WFPC exposures obtained via the Medium Deep Survey (MDS) provide unique high resolution imaging data which cannot be obtained in reasonable allocations of primary time. For statistical programs in extragalactic and Galactic astronomy, source counts parameterized by morphology, magnitude, color and scale-length constitute an invaluable database for long term programs in cosmology, galaxy evolution and Galactic structure. Although the original goals of the MDS were severely limited in Cycles 1-3, we have demonstrated dramatic progress in each of these areas in the 6 months during which Cycle 4 data has been available. Highlights include the realization that the bulk of the familiar Hubble sequence of galaxies was in place at z~eq0.5, the recognition of large numbers of faint irregular galaxies, and our ability to discover unusual objects by virtue of the large areas spanned by the MDS. Considering the accelerated progress now established, we are requesting continuation of the MDS into Cycle 5. Our new strategy takes full account of our projected achievements in Cycle 4 and is optimized to explore the unique parameter space of parallel data more effectively viz. (i) building up significant samples of rare objects (e.g. lensed objects, peculiar galaxies, faint stars), (ii) studying the sources which hold the key to resolving the faint blue galaxy problem. Our proven on-going access to large ground-based telescopes is a major strength of the team. Questions ! Free format text (please update) Observing_Description: MDS OBSERVING STRATEGY FOR CYCLE 5 In a stack of four half- orbit exposures totalling 7500s, the magnitude limits for reliable measurements of individual objects are 26.5 mag for point sources and 26 mag for typical galaxies in I (F814W), and about 0.5 mag fainter in V (F606W). At fainter levels, we observe sky fluctuations that can be resolved into individual galaxies, but measurements of their structural parameters are less reliable. For the same exposure, star-galaxy separation can be achieved to 25.5 mag in V, compared to a ground-based separation limit of V ~ 22 mag. Longer exposures would not gain substantially in limiting magnitudes, although they could improve star-galaxy separation and measurement of structural parameters, both of which are limited by photon counting noise. For B (F450W) we estimate the detection limits to be about 0.5 mag brighter, and the star-galaxy separation limit about 1 mag brighter than in V. With the experience from previous cycles, we propose to continue with the following strategy: (i) It is vital that as much parallel time as possible be used for WFPC2 exposures so as to maximize HST scientific productivity. Results from the MDS have vindicated the effort expended in the development of parallel operations, which increase the overall observing efficiency of HST by ~ 50\ We continue to emphasize the use of WFPC2 in parallel mode at every opportunity for exposure times greater than 500s. In particular, multi-orbit exposures in each band are needed for all aspects of the Medium Deep Survey: for search and study of galactic nuclei, rare galaxy morphology, for the detection of faint stars, etc. (ii) The scientific productivity of the Survey has been enhanced by biasing use of WFPC2 at high galactic latitudes as far as possible into the I-band. The I-band has the greatest space-advantage with respect to ground-based observations, by virtue of the elimination of the atmospheric hydroxyl bands and the resulting factor of ~ 10 reduction in sky background (~eq 22.3 mags arcsec^-2 at 8930Angstrom at the NEP). (iii) For pointings of 1 -- 3 orbits, we retain our plan of obtaining I-band exposures, with the addition of the V-band for parallel opportunities of 4 -- 7 orbits. A minimum of 3 exposures in each filter is required to make a stack free of cosmic rays. (iv) For pointings of 8 or more orbits, which we expect to continue to constitute the most interesting part of the Survey, the I- V-bands will still be used, but with B-band imaging added to get color information, and especially to isolate bluer structures. In Cycle 5, we propose to obtain extra color information in the near-UV (F255W) on a subset (at least two or three) of the deepest low b^II survey fields exceeding 6 orbits. (v) HST Calibration exposures on bright stars will provide the opportunity for repeated observations and will also provide an annular coverage that will be used for correlation studies of faint galaxies, as a function of galaxy type and structure or morphology. We expect a few calibration fields to be available eventually for this purpose. begintable def\mk#1 ^ #1 vbox 5pt plus 2pt centerline Table 1: Explanation of types of observations \medskip to hsize # && # noalign 1pt Depth & N. Orbits & \# expected & Filtersmka &Multispan3 Limiting magnitude & & per cycle & & Detection & Disk/bulge & Morphology noalign Shallow & 1--3 & 90 & I & 25 & 23 & 21 Medium & 4--7 & 20 & VI mkb & 26.5/26 & 25/24 & 23/22 Deep & 8 --12 & 5 & BVI mkc & 26/26.5/26 & 24/25/24 & 22/23/22 noalign 1pt -5pt begindescription 0pt vspace-0.27in itema) For WFPC2, I is F814W; V is F606W; B is F450W; U is F255W itemb) At low galactic latitudes, B will be used instead of V itemc) At low galactic latitudes, U will be added for the longest pointings vspace -7mm enddescription endtable WFPC2 will thus be used for parallel observations at every opportunity for exposure times greater than 500 s in random fields at $b > 10^ o , with an assumed average observing time of 2500 s per orbit; in these fields, exposure times less than 500 s are unlikely to be very valuable for faint galaxy work. However, at lower latitudes, and within nearby galaxies, shorter integrations are extremely useful. Single filter exposures/orbit will be split wherever possible for detection of particle radiation background (~2 - 3 events per CCD sec^-1, depositing typically 100-1000 electrons) The Observing Strategy summarized in Table 1 will provide a balanced overall parallel program while satisfying the requirements on the total number of fields and filter combinations for the science objectives of the MDS (Table 2). The final assignments and filter choices will depend on the distribution of orbits in the Cycle 5 GO primary pointings. We will continue to work with STScI personnel to optimize the program and filter usage. The scientific goals of the MDS and the expected number of exposures necessary to achieve them are summarized in Table 2. begintable def\mk#1 ^ #1 vbox centerline Table 2: MDS Projects and Observational Requirements for Cycles 4--6 \medskip tohsize # 4pt plus 2pt & # & #& #& #& #& #& # 0pt noalign 1pt Project & Type of objects & \# obj. & \# per & I_ lim & V_ lim & Fields & Statusmkc & and observationsmka & reqd.mkb & field & & & reqd. & noalign noalignnoindent Extragalactic: Number and structural parameters Number counts & V and I phot & 10000 & 200 & 24 & 26 & 50 M & C5 Number counts vs. type & Morphology & 3000 & 25 & 22 & -- & 120 S & C4 Color vs. mag and type & E/S class, V-I & 2000 & 200 & 24 & 26 & 10 M & A BVI colors vs. morphology & Morph, BVI & 500 & 25 & 22 & 24 & 20 D & LT Size distribution & All galaxies & 10000 & 500 & 26 & -- & 20 S & A Size vs. color & V-I & 10000 & 200 & 24 & 26 & 50 M & C5 noalign\medskip phantom Extragalactic: Merging, pairing and angular correlation function Parents/satellites (Delta m<4 ) & Morph, V-I & 500 & 6 & 20 & 22 & 80 M & C6 Color gradients of parents & BVI & 100 & 6 & 20 & 22 & 15 D & C6 Color of major mergers & BVI & 100 & 3 & 22 & 24 & 30 D & LT Galaxy pairs & Pairs ( d ~ 1'') & 500 & 5 & 23 & -- & 100 S & C4 Pairing vs. type, color & Pairs, color, E/S & 1000 & 5 & 23 & 25 & 200 M & LT CF vs. type - bright end & E/S class & 10000 & 25 & 22 & -- & 500 S & LT CF vs. type - faint end & E/S class & 20000 & 200 & 24 & -- & 100 S & C4 noalign\medskip phantom Extragalactic: Properties of rare objects AGN and nuclear starburst & Well -resolved galaxies & 200 & 2-3 & 21 & 23 & 80 M & C6 Colors of above & BVI of above & 50 & 2 & 20 & 22 & 25 D & LT Double nuclei & Morphology & 100 & 0.3 & 22 & - - & 300 S & C5 Super starforming knots & V-I , good depth & 100 & 0.2 & 23 & 25 & 500 M & LT Very low SB objects & V-I , good depth & 20 & 0.03 & 24 & 26 & 600 M & LT Compact objects & BVI photometry & 200 & 3 & 22 & 23 & 70 D & LT Diffuse starforming gal. & Morph, BVI & 100 & 3 & 22 & 23 & 30 D & LT Shreds (low SB fragments) & V-I , good depth & 100 & 1--2 & 24 & 26 & 50 M & C5 noalign\medskip noindent Galactic: Structure and stellar populations of the Galaxy Luminous mass density & Faint stars at b > 30^ o & 50 & 1 & 23 & 26 & 50 M & C5 LF of K-M dwarfs & Faint star counts vs. b & 2000 & 20 & 23 & 26 & 100 M & LT Spheroid turnoff & Faint stars at b > 30^ o & 200 & 1 & 22 & 26 & 200 M & LT Galactic length scales & Star counts at b < 20^ o & 10000 & 100 & 24 & 26 & 100 M & LT noalign 1pt begindescription =0pt vspace -0.27in itema) Morphology indicates detailed morphological classification and disk/bulge separation for spirals; E/S indicates automated classification into bulge- dominated and disk-dominated galaxies by model fits; B, V, I stand for F450W, F606W, F814W respectively. vspace-2mm itemb) Fields required are divided into S(hallow), M(edium), and D(eep) according to Table 1; because of our observing strategy, a field of greater depth can also be used. The number required is for optimal completion of project, but for some projects---esp. on rare objects---useful information can be gained with only a fraction of the stated requirements. vspace-2mm itemc) Status is A (achieved) if data are already in hand (Aug 1, 1994); C4/5/6 if we expect to acquire the data by the end of Cycle 4/5/6 resp. at current rate (see table below); LT (long term) if data are not expected by the end of Cycle 6. enddescription endtable \medskip DATA ANALYSIS 0.05in The MDS Team has established the MDS database and developed a detailed Working Group plan over the past several years. All Cycle 1--3 data have been recalibrated using the MDS super-sky flat fields and other improvements in calibrations which resulted in a gain of at least 0.3 mag in sensitivity (Ratnatunga et al 1994a, AJ in press - R94a), and all the data have been processed, searched and objects parameterized. The resulting calibration files for WF/PC and WFPC2 have been made publicly available on STEIS, together with the complete object catalog -- the HST MDS Catalog from WF/PC. In order to subdivide and coordinate the effort in individual programs, the MDS team has formed several Working Groups with well-defined goals, roughly following those outlined in sections II through IV above. The Working Groups are each led by the PI or a co-I, with well- defined short-range and long-range goals in terms of data analysis and publications. The Working Group Plan has had input from all co-Is and team associates, and is reviewed and updated as the need arises. The Working Groups are those of : (1) AGN and starburst nuclei; (2) Stars and stellar systems; (3) Galaxies, subdivided into (i) Bright galaxies, (ii) Statistical properties of full galaxy sample, (iii) Statistics via Eyeball Classification; (iv) Galaxy Mergers and interactions, (v) Galaxy morphology via Combined Ground- Based/HST Imaging; (4) Serendipity; (5) Ground-Based Follow- up; (6) Database and Calibration The establishment and experience of the working groups has meant that the suggested 6-month proprietary period will constitute sufficient lead- time for the extraction of our basic results and for the preparation of papers for publication. Real_Time_Justification: vspace-3mm None vspace-2mm GROUND-BASED OBSERVATIONS 0.05in To optimize the use of HST, we have undertaken an extensive program of ground-based follow-up work, recognizing that it is vital that complementary redshifts and spectral data be gathered for at least a complete subsample of the MDS data. Near infrared, radio, and additional broadband and narrow band optical imaging, etc., is also being supplied from the ground, especially for the small number of high galactic latitude areas that have or will receive multiple orbit observations. We plan to continue to invest at least two nights of 4m-class optical telescope time for each of a selected set of WFPC2 frames for multiaperture spectroscopy to V~ 23, using instruments such as the low dispersion multi-object spectrographs at the MMT, WHT and AAT. The mismatch between the WFPC2 field and that of the multi-object spectrographs is ameliorated to the maximum extent possible in our follow-up work, i.e. we can optimize the selection of HST objects for spectroscopy once the image has been processed. With the MMT, WHT, Mayall 4 meter, and AAT we have made multi-slit masks with 8--12 slits in each WFPC field with less than 10 days lead-time. We have repeated this with up to 5 masks per field, and on several occasions measured 35 spectra in a single WFPC2 field (D94), or ~8--10 objects per square arcmin. We also take advantage of the a priori knowledge of the accurate location of the HST galaxy core (and/or H-II regions) from astrometry on the WFPC2 images. The median scale-length of MDS galaxies is 0.3''--0.4'' (G94a), so that in good seeing, we can optimize the multi-slit spectrograph throughput by using 0.5''-0.75'' slits, thereby optimizing the number of measured redshifts per unit time ( e.g. 48 redshifts down to V~24 mag in only two short nights at MMT). We regard it as a much more efficient use of HST time to measure the redshifts this way i.e. a posteriori, rather than spending a large amount of HST time on wide fields with pre-existing redshift surveys. The latter always have the problem of low surface density (~1--2 redshifts per square arcmin), and are therefore prohibitively expensive in HST follow-up time. In an adjunct program for Cycle 5, we have arranged a limited collaboration with Carlberg, Pritchet, Yee and Morris, who will propose to use CFHT for a long-term program to carry out a major spectroscopic survey of redshifts and velocities. Although their survey is largely independent of the MDS, they will select areas which will overlap at least four of our deepest MDS fields. In addition, we will typically use half a night for additional multicolor photometry, and half a night for near infrared imaging for full ground-based optical support. These observing times have been exceeded on the WF/PC 3C273 and 13H+42^o fields at the MMT and WHT (spectroscopy), and the Steward 90-in, KPNO 4m, and CFHT (photometry). Such data give us the redshift-color- size, etc. correlations that allow us to understand our larger data set in terms of galaxy type vs. redshift. Altogether, at least 100 nights of optical telescope time over a 3 to 5 year follow-up period are realistic goals for our team, and thus we should be able to optimize the usefulness of a significant fraction of the MDS data base. We have long-term status on the MMT and Steward Observatory telescopes (9 nights per year on each); in 1994 we will have used a total of 12 nights (12n) at the MMT, 3n on the WHT, 7n at KPNO 4m, 5n at Las Campanas, 2n at Keck. Calibration_Justification: ! Move appropriate text from Real_Time_Justification Additional_Comments: Generic_Targets ! Section 5.3 Target_Number:1 Target_Name:PAR Description:CLUSTER OF GALAXIES Criteria:ABS_BII > 10D Flux: Comments: ! This is a template for a single visit containing a single exposure ! Repeat exposure and visit blocks as needed Visits ! Section 6 Visit_Number:1 Visit_Requirements: ! Section 7.1 ! Uncomment or copy visit level special requirements needed ! Most of these requirements (including ORIENT) will limit scheduling ! PCS MODE [Fine | Gyro] ! GUIDing TOLerance ! ORIENTation TO ! ORIENTation TO FROM ! ORIENTation TO FROM NOMINAL ! SAME ORIENTation AS ! CVZ PARallel ! AFTER [BY [TO ]] ! AFTER ! BEFORE ! BETWEEN AND ! GROUP WITHIN