Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 5304 Report Date: 18-Jul-95:17:07 Version: ********** Check-in Date: ********** 1.Proposal Title: QSO ABSORPTION-SELECTED GALAXIES IN THE FIELD OF 3C336--CYCLE 4 HIGH ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID QUASARS & AGN GO Sub Category QUASAR ABSORPTION ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Charles C. Steidel 2630 USA 617-253-5084 ------------------------------------------------------------------------------------ 7. Abstract We propose to obtain high resolution WFPC2 images of the field of 3C 336, a quasar with z=0.927 in whose spectrum 3 foreground MgII absorption systems with z= 0.472, 0.656, and 0.892 are known, making it the richest field in a nearly completed survey for absorption--selected galaxies which we have been conducting using ground-based observations. Optical and infrared colors, magnitudes, positions, and redshifts have already been measured; based upon the unusually small impact parameters of two of these galaxies (z=0.656,0.892) with the line of sight to the quasar, and the very strong absorption lines observed in the optical spectra, we can predict with some certainty that they are galaxies which are producing damped Lyman alpha lines. Using FOS spectra of the QSO aimed at measuring HI column densities in these two systems (together with ground- based spectra aimed at detecting ZnII and CrII absorption lines) and the high resolution WFPC2 images, it will be possible to establish chemical abundances, dust content, and kpc-scale morphology for the same galaxies, providing an unprecedentedly complete picture of apparently normal galaxies at lookback times of one--half the age of Universe. The fact that there are three absorbing galaxies in a single field makes the imaging observation a particularly efficient one for HST. ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 7.62 par: 0 10. Num targs pri: 2 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: FOS WF/PC ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 5304 PI: Charles C. Steidel Proposal Title: QSO ABSORPTION-SELECTED GALAXIES IN THE FIELD OF 3C336--CYCLE 4 HIGH ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Charles C. Steidel 2630 USA Mark E. Dickinson 3470 USA David M. Meyer 3020 USA ------------------------------------------------------------------------------------ 3. Description of proposed observations. FOS spectra using FOS/RD and G190H and G270H wil be obtained of the quasar 3C336. The object will be observed through the 1.0 aperture acquiring using an ACQ/BINARY sequence. Exposures of length 3600s and 2700s, for G190H and G270H, respectively, will be obtained, in the ACCUM mode. WFPC-2 observations of the field of 3C336, centering on the WF2-FIX aperture. We have requested a special ORIENT of 100 degrees in order to avoid blooming of the bright quasar in the direction of one of the faint galaxies of interest, and to include as many galaxies of interest in the field of view. The objects of primary interest for the WFPC-2 images are faint high redshift (z=0.3-0.9) galaxies, with the most important objects being closest to the nominal position (i.e., the quasar) of the field. All of the WFPC2 exposure will be made with the F702W filter, each exposure being 1000s in duration, with no CR-SPLIT. The 24 exposure are broken into 3 groups of 8,8, and 8 exposures respectively, with the telescope being moved by a small amount (~2 arc sec) in between groupings.The same orientation angle has been requested for all of the WFPC-2 exposures. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. The program has been carried out to the fullest extent possible using ground-- based observations; HST is essential to perform the UV spectroscopy necessary to obtain values for the HI column densities of the z=0.656 and z=0.892 absorbing galaxies, as the Lyman alpha features are at 2014 Angstroms and 2300 Angstroms, respectively. The WFPC-2 observations are necessary to obtain kpc-- scale morphological information for both the absorbing galaxies and for the other moderate redshift galaxies in the same field for which spectroscopic redshifts have already been obtained. The HST images are also needed in order to fully resolve the faint absorbing galaxies from the relatively bright background QSO. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. ------------------------------------------------------------------------------------ 9. Description of previous HST work. None of the investigators has been PI of previous HST proposals. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). Extensive computing and image processing facilities will be available at each of the participating institutions, as well as the usual secretarial and administrative facilities. MIT will provide access to the MDM 1.3m and 2.4m telescopes on Kitt Peak, for any futher ground--based support of the program. It is anticipated that a graduate student at MIT will be invited to participate in the reduction and analysis of the data. Academic year salaries are provided for Steidel and Meyer by their respective institutions, and Dickinson will be supported year--round by STScI. Page 3 ------------------------------------------------------------------------------------ 11. Address Information Name: Charles C. Steidel Category: PI Institution: 2630 Address: MIT Physics Department, Room 6-201 77 Massachusetts Avenue City: Cambridge State: MA Zip Code: 02139 Country: USA Telephone: 617-253-5084 Telex (or e-mail): steidel@trystero.mit.edu ------------------------------------------------------------------------------------ Name: Category: CON Institution: Address: City: State: Zip Code: Country: Telephone: Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 5304 [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial |Acqui|FLX| Flux data No | Name | Description | Position |Eqnx | Vel. |Prblm|REF| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 1 3C336.0 E,314,325, PLATE-ID=02BA, J2000 Z=0.927 1 V=17.6 +/- 0.1 Q1622+2352 H,515,516 RA = 16H 24M 39.08S +/- 2 E(B-V)=0.03 +/- 0.03 1.0", 3 F-CONT(2000)=7.0 +/- 1.0 E-16 DEC = +23D 45' 12.6" +/- 4 F-CONT(2300)=6.0 +/- 1.0 E-16 1.0" Comments: FLUX NEAR 2000 A ASSUMES POWER LAW WITH ALPHA=0.7 EXTRAPOLATED FROM 3100 A, AND ASSUMES A(2000)=0.24 MAGS. FEATURES OF PRIMARY INTEREST ARE AT 2000 A AND AT 2300 A. ------------------------------------------------------------------------------------------------------------------------------------ 2 3C336.0- E,314,325, RA = 16H 24M 39.08S +/- J2000 Z=0.9 5 SURF(R)=25 FIELD H,515,516 1.0", Q1622+2352- DEC = +23D 45' 12.6" +/- FIELD 1.0", PLATE-ID=02BA Comments: OBJECTS OF INTEREST ARE FAINT (R=23) GALAXIES IN THE FIELD OF THE QSO. THE SURFACE BRIGHTNESS IS DIFFICULT TO ESTIMATE, AND DEPENDS UPON UNKNOWN MORPHOLOGY. DESIRE REACHING SURFACE BRIGHT - NESS LIMITS (5 SIGMA) PER *PIXEL* OF R=29.8. ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 5304 [ 5] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 3C336.0 FOS/RD ACQ/ 4.3 MIRROR 1 16.5S 1 1 CYCLE 4 BINARY ONBOARD ACQ FOR 1.1,1.2 GROUP 1.0,1.1,1.2, 5.0,6.0,7.0 WITHIN 2D ------------------------------------------------------------------------------------------------------------------------------------ 1.1 3C336.0 FOS/RD ACCUM 1.0 G270H 1 3400S 4 1 CYCLE 4 Comments: FEATURE OF INTEREST IS A BROAD ABSORPTION FEATURE CENTERED AT 2300 A. EXPOSURE IS DESIGNED TO OBTAIN S/N PER DIODE OF APPROX 25 AT THAT WAVELENGTH. ------------------------------------------------------------------------------------------------------------------------------------ 1.2 3C336.0 FOS/RD ACCUM 1.0 G190H 1 4400S 3 1 CYCLE 4 Comments: FEATURE OF INTEREST IS A BROAD ABSORPTION FEATURE CENTERED AT 2013 ANGSTROMS. EXPOSURE DESIGNED TO GET S/N APPROX. 20 PER DIODE IN THE CONTINUUM AT THAT WAVELENGTH. ------------------------------------------------------------------------------------------------------------------------------------ 5 3C336.0- WFPC2 IMAGE WF2-FIX F702W CR-SPLIT=NO 8 1000S 10 5 1 CYCLE 4 FIELD ORIENT 100D +/- 10D SAME ORIENT FOR 6- 7 AS 5 POS TARG 0,-5 Comments: FIRST OF 3 POSITIONS, SEPARATED BY SMALL SHIFTS. THE ORIENT IS TO PLACE U3 AXIS AT SKY PA=10 DEGREEES, TO INCLUDE OBJECTS OF INTEREST AND TO CONTROL DIRECTION OF QSO BLOOMING. ------------------------------------------------------------------------------------------------------------------------------------ 6 3C336.0- WFPC2 IMAGE WF2-FIX F702W CR-SPLIT=NO 8 1000S 10 5 1 CYCLE 4 FIELD POS TARG +1.5,-3.5 Comments: SECOND OF 3 POSITIONS, SEPARATED BY SMALL SHIFTS. THE ORIENT IS SPECIFIED IN ORDER TO PREVENT BLOOMING OF THE QSO IN THE DIRECTION OF ONE OF THE GALAXIES OF INTEREST. ------------------------------------------------------------------------------------------------------------------------------------ 7 3C336.0- WFPC2 IMAGE WF2-FIX F702W CR-SPLIT=NO 8 1000S 10 5 1 CYCLE 4 FIELD POS TARG +1.5,-6.5 Comments: THIRD OF 3 POSITIONS, SEPARATED BY SMALL SHIFTS. THE ORIENT IS SPECIFIED IN ORDER TO PREVENT BLOOMING OF THE QSO IN THE DIRECTION OF ONE OF THE GALAXIES OF INTEREST. ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 5304 [ 6] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOS/RD WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/BINARY ACCUM IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 7.62 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category QUASARS & AGN ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category QUASAR ABSORPTION ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements CYCLE 4; ONBOARD ACQ FOR 1.1,1.2; GROUP 1.0,1.1,1.2,5.0,6.0,7.0 WITHIN 2D ORIENT 100D +/- 10D; SAME ORIENT FOR 6-7 AS 5; POS TARG 0,-5 POS TARG +1.5,-3.5; POS TARG +1.5,-6.5; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G270H G190H F702W ------------------------------------------------------------------------------------------------------------------------------------ Target Names 3C336.0 Q1622+2352 3C336.0-FIELD Q1622+2352-FIELD ------------------------------------------------------------------------------------------------------------------------------------