Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 5442 Report Date: 18-Jul-95:17:24 Version: ********** Check-in Date: ********** 1.Proposal Title: SPECTROPHOTOMETRY AND IMAGING OF THE LENSED, CLOVER LEAF BROAD ABSORPTION LINE QSO 1413+117-PART II-CYC 4 HIGH-IMAGING ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID QUASARS & AGN GO Sub Category GRAVITATIONAL LENSES ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Dr. David A. Turnshek UNIVERSITY OF PITTSBURGH USA (412) 624-9015 PROFESSOR ------------------------------------------------------------------------------------ 7. Abstract Observations of the gravitationally lensed "Cloverleaf" Broad Absorption Line (BAL) QSO Q1413+117 are proposed as a follow-on to a Cycle 1 proposal. Red and UV WFPC2 images and FOS spectra will be taken to achieve the following aims: (1) The red WFPC2 PC images will be used as an EARLY ACQ and to search for other component images and the lensing galaxy, followed by FOS observations to determine the galaxy's redshift. The information will be used to delineate and model the geometry of this unique gravitationally lensed BAL QSO. (2) FOS data on the QSO image components will be used to check sight-line dependent differences in the BAL profiles. The results can be used to place constraints on BAL region cloud sizes and shapes. (3) The same FOS observations will be used to constrain the sizes and shapes of Ly-alpha forest clouds and two intervening narrow absorption-line metal systems. (4) The UV and red images will be compared to search for possible sight-line dependent differences in dust-extinction. Thus, results from this study will yield relevant information on a number of different important astrophysical problems. ------------------------------------------------------------------------------------ 8. Scientific Key Words: GRAVITATIONAL LENSING, BROAD ABSORPTION LINES, NARROW ABSORPTION LINES, IMAGING, SPECTROPHOTOMETRY ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 8.00 par: 0 10. Num targs pri: 6 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: FOS WF/PC ------------------------------------------------------------------------------------ 12. Special sched req: Real Time obs. ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 5442 PI: Dr. David A. Turnshek Proposal Title: SPECTROPHOTOMETRY AND IMAGING OF THE LENSED, CLOVER LEAF BROAD ABSORPTION LINE QSO 1413+117-PART II-CYC 4 HIGH-IMAGING ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Olivia L. Lupie COMPUTER SCIENCES CORPORATION USA P.I. David A. Turnshek UNIVERSITY OF PITTSBURGH USA ------------------------------------------------------------------------------------ 3. Description of proposed observations. The proposal consists of Early-Acquisition WFPC2 images and FOS Grating 400 spectra of the 4 QSO image components and the lensing Galaxy. The observing procedure is straightforward. We require an Interactive Acquisition of the target into the FOS 4.3 arcsec aperture. This specialized procedure is necessary because the proximity of the four components (within 1 arcsec) precludes other standard onboard techniques and the use of an offset star requires a high level of Science Instrument alignment accuracy. Also, the technique of the interactive acquisition has been tested in our Cycle 1 program and proved an excellent method to acquire the target. WFPC2 IMAGES: PC1 images will be used to discover the lensing galaxy, provide relative photometry on the QSO components, and serve as EARLY ACQUISITION images. From these early images we will extract relative coordinates of the 4 lensed components, coordinates of the (so far unseen) lensing galaxy and any additional image components. These coordinates will be used for the subsequent FOS observations. Note that the long red WFPC2 image is split into 3-900 second exposures to prevent blooming. Standard Mode III target acquisition is acceptable. FOS OBSERVATION STRATEGY: The FOS observations are several orbits long and therefore we require two guide star tracking to minimize roll drift. If two guide stars are not available or FGS2 is de-commissioned, peak-up exposures must be inserted every few orbits. Based on recent experience with the Cycle 1 program, it is most prudent to request a real-time acquisition into the 4.3 arcsec FOS aperture (see quest. 5). Prior to each QSO component observation, we will perform a peak-up into the 0.5" aperture. The small aperture is required to prevent impingement on the signal from the nearby (within 1 arcsec) QSO image components. Finally we will perform a SAM (based on the early acquisition) to the central lensing galaxy and acquire a spectra. PREVIOUS HST EXPERIENCE WITH TARGET AND GUIDING: There was a paucity of guide stars available for our Cycle 1 (executed in Summer 1993) program and therefore the window of opportunity was limited. Even though many restrictions will be eliminated as a result of the servicing mission fixes, the guide star options are still limited. In order to maximize scheduling flexibility for this high priority program, a full-year guide star request for this target is recommended to identify windows at the outset of scheduling. NOTE: THIS PART OF THE PROGRAM IS THE EARLY ACQ IMAGING PART ONLY. THE INT ACQ IMAGING AND FOLLOW-UP SPECTROSCOPY IS IN A DIFFERENT PROGRAM ID AS REQUIRED BY THE PLANNING AND SCHEDULING SYSTEM. THE SPECTROSCOPY, ALONG WITH NECESSARY CONTEMPORANEOUS IMAGING, IS IN THE CYCLE 4 PROGRAM GO 5621. Page 3 ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. High spatial resolution optical observations with HST are required because the lensing galaxy and the QSO component images are closely spaced on the sky, all lying within 0.7 arcsec of the center of the image. Other images not detectable from the ground may also be present and their identification would be important in understanding the lens geometry. The lensing galaxy is likely to lie within a few tenths of an arcsec from one of the bright images. Moreover, in order to check for spectral differences (which this program proposes to measure), each image of the QSO must be free of contaminating light from the other images. Therefore, HST is required for these observations. A UV image is also requested to check for the presence of possible dust-extinction irregularities. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. REAL-TIME ACQUISITION: We request a standard REAL-TIME target acquisition of component A into the 4.3 arcsec aperture. This will allow 0.2 arcsec accuracy. Due to the proximity of the images (within 1 arcsec) and possible variability of the components, binary search on the QSO is not possible. The option of doing a binary search on the nearby offset star may be feasible pending two conditions: (1) the star falls well within one of the CCDs in the early acquisition images so that its relative position can be measured, and (2) that the WFPC2 alignments are known with sufficient accuracy: WFPC2 CCD orientations <= 0.3 degrees and positional accuracy better than 0.5 arcsec. The offset star will fall in a different CCD than the target star. If these conditions are verified after the servicing mission, we will submit a change request to remove the interactive acquisition. OSS Requirements: The real-time acquisition procedure is standard. We request target centroid positions, comparison of total counts in each QSO component, and calculation of a slew maneuver. This was done with great success for Cycle 1 data. EARLY ACQUISITION: Because of variability concerns, SEQ NO GAP has been appended to the WFPC2 image set and GROUP NO GAP to the FOS spectral data. The WFPC2 data are used as EARLY ACQUISITION and so must be performed several months before the FOS observations. GUIDE STAR AVAILABILITY: Because of the paucity of guide stars, we request that a full-year guide star request for this target be performed at the outset of scheduling activities. This will help minimize major delays and scheduling inefficiencies. NOTE: THIS PART OF THE PROGRAM IS THE EARLY ACQ IMAGING PART ONLY. THE INT ACQ IMAGING AND FOLLOW-UP SPECTROSCOPY IS IN A DIFFERENT PROGRAM ID AS REQUIRED BY THE PLANNING AND SCHEDULING SYSTEM. THE SPECTROSCOPY, ALONG WITH NECESSARY CONTEMPORANEOUS IMAGING IS IN THE CYCLE 4 PROGRAM GO 5621. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. No special calibration exposures are required. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. Special Requests: Interactive Acquisition: We request support for our interactive FOS acquisition. The activities we require of OSS are standard procedure. Because of the paucity of guide stars for this target, we experienced many long delays in scheduling of our cycle 1. We were advised by the scheduling group that we request that STScI generate a year-long guide star availability report at outset of reviewing this proposal. Page 4 ------------------------------------------------------------------------------------ 9. Description of previous HST work. GTO No.1145: Imaging and Spectroscopy of the Low Redshift BAL QSO PG1700+518 (Weymann, PI) - partly related project in the sense that a BAL QSO is being studied. GTO No.1146: Spectroscopic Studies of Several High Redshift BAL QSOs (Weymann, PI) - also a partly related project; the ultraviolet spectrum of the brightest image of Q1413+11 will be measured with the FOS at low resolution (G160L and PRISM) in two short exposures totaling 15 minutes. GO No. 4213: SPECTROPHOTOMETRY AND IMAGING OF THE LENSED, CLOVER LEAF, BROAD ABSORPTION LINE QSO 1413+11, Part I ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). Institutional support includes: academic year salary for the PI and some administrative help. ------------------------------------------------------------------------------------ 11. Address Information Name: David A. Turnshek Category: PI Institution: 3170 Address: University of Pittsburgh Department of Physics and Astronomy Allen Hall City: Pittsburgh State: PA Zip Code: 15260 Country: USA Telephone: 412-624-9015/9000 Telex (or e-mail): email is turnshek@vm2.cis.pitt.edu ------------------------------------------------------------------------------------ Name: Olivia L. Lupie Category: CON Institution: 3470 Address: STScI 3700 San Martin Dr. City: Baltimore State: MD Zip Code: 21209 Country: USA Telephone: 410-338-4827 Telex (or e-mail): STSCIC::LUPIE or lupie@stsci.edu ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 5442 [ 5] ------------------------------------------------------------------------------------------------------------------------------------ 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 Q1413+117 E,313,323 RA= 14H 15M 46.3S +/- 0.1S, 2000 EXT 1 V=17 +/- 0.4 DEC= 11D 29' 43.6" +/- 1.5" Comments: QSO FIELD CENTER ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 5442 [ 6] ------------------------------------------------------------------------------------------------------------------------------------ 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 Q1413+117 WFPC2 IMAGE PC1 F255W ATD-GAIN=7 3 800S 28 1 1 SEQ 10-12 NO GAP CR-SPLIT=NO CYCLE 4 /10-12 Comments: EARLY ACQ IMAGES FOR LATER INT ACQ AND ALSO FOLLOW-UP SPECTROSCOPY, BOTH OF WHICH ARE IN CYCLE 4 GO 5621. ------------------------------------------------------------------------------------------------------------------------------------ 11 Q1413+117 WFPC2 IMAGE PC1 F702W ATD-GAIN=7 1 200S 20 1 1 CR-SPLIT=0.5 CR- TOLERANCE=0.0 Comments: RELATIVE PHOTOMETRY ON QSO COMPONENTS. ------------------------------------------------------------------------------------------------------------------------------------ 12 Q1413+117 WFPC2 IMAGE PC1 F702W ATD-GAIN=7 3 900S 20 1 1 CR-SPLIT=NO Comments: EARLY ACQ IMAGES FOR LATER INT ACQ AND FOLLOW-UP SPECTROSCOPY, BOTH IN A DIFFERENT PROGRAM, CYC4 GO 5621. QSO COMPONENTS WILL BE SATURATED. LENS GALAXY SHOULD EMERGE IN IMAGE. ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 5442 [ 7] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ATD-GAIN=7 CR-SPLIT=NO CR-SPLIT=0.5 CR-TOLERANCE=0.0 ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 8.00 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category QUASARS & AGN ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category GRAVITATIONAL LENSES ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements SEQ 10-12 NO GAP; CYCLE 4 /10-12; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F255W F702W ------------------------------------------------------------------------------------------------------------------------------------ Target Names Q1413+117 ------------------------------------------------------------------------------------------------------------------------------------