5908( 0) - 07/18/95 18:34 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 5908 Version: ********** Check-in Date: ********** 1.Proposal Title: HST observations of new CLASS gravitational lenses ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle Quasars GO 5 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Neal Jackson NRAL Jodrell Bank CoI: Chris Fassnacht Caltech N CoI: George Miley Leiden Observatory N CoI: Ger de Bruyn Dwingeloo N CoI: Ian Browne NRAL Jodrell Bank N CoI: Richard Schilizzi Dwingeloo N CoI: Peter Wilkinson NRAL Jodrell Bank N CoI: Malcolm Bremer Leiden Observatory N CoI: Sunita Nair NRAL Jodrell Bank N CoI: Steve Myers Caltech N CoI: Tony Readhead Caltech N CoI: Tim Pearson Caltech N CoI: Roger Blandford Caltech N ------------------------------------------------------------------------------------ 6. Abstract We propose to examine a few of the very best lens candidates from a new gravitational lens survey, the Cosmic Lens All-Sky Survey (CLASS) made with the VLA. We are virtually certain that we have one new lens system (1600+434) and another (1609+655) has a radio configuration which almost invariably indicates gravitational lensing. The other cases are systems which have a high probability of being lenses (statistically we would expect at least 5 of the 10 objects should be lensed, since we have imaged >3000 radio sources and experience shows that 1 in 500 are lensed). All have separations which make them difficult to study from the ground and therefore uniquely suited to the capabilities of the HST. In this investigation we will study 1600+434 and 1609+655 and attempt to image the lensing galaxy. We will image the remainder in an attempt to confirm their lens status (which requires 0.1" resolution imaging typically) and search for lensing galaxies and/or clusters in those found to be lensed systems. ------------------------------------------------------------------------------------ 5908( 0) - 07/18/95 18:34 - [ 2] Observations Description ------------------------ The observations are aimed at detecting point objects of magnitude 20 together with extended galaxies of integrated magnitudes down to about 20 to 21. In the 555 filter the point object will produce about 55 electrons per second. An extended galaxy of similar brightness will produce about 2 electrons per second in the central pixel assuming a redshift of about 0.6 and using the curve of figure 6.1. in the WFPC2 handbook. The figures for the 814 filter are roughly similar. We propose to take two exposures in each filter: one short (so as not to saturate on the point sources) and one long in order to search for any lensing galaxy. The available observing time per orbit is between 43 and 47 minutes, taking into account occultation and guide star acquisition. Allowing 16 minutes for exposure overheads (one CR-SPLIT and one NO-CR -SPLIT in each filter) this gives between 27 and 31 minutes for science exposures. In the deeper exposure in each filter we will therefore obtain about 12-15 minutes' integration. This will be enough to collect 1400 electrons in the central pixel of any lensing galaxy. The point sources will be easily detected in the short (~1 min) exposures (note that objects listed as magnitude >20 will almost certainly be <21.5 as they are flat spectrum radio sources). Real Time Justification ----------------------- We are conducting imaging and spectroscopic observations with the Keck telescope for optical ground based followup of the lens candidates, and the wide--separation lens in figure 1 which was confirmed using the William Herschel Telescope on La Palma. These ground based telescopes are not adequate for the investigation suggested here for the reasons presented above. MERLIN and VLBA will be used for radio followup of suspected lenses. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: , ------------------------------------------------------------------------------------ 5908( 0) - 07/18/95 18:34 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 QSO- GALAXY RA=16H 1M 40.46S +/- 0.01S, 2000 Z=1.6 V=20.0 +/- 0.5 160140+43164 DEC=43D 16' 47.5" +/- 0.1" 7 2 QSO- GALAXY RA=16H 9M 13.96S +/- 0.01S, 2000 V=18.9 +/- 0.5 160913+65322 DEC=65D 32' 28.9" +/- 0.1" 8 3 QSO- GALAXY RA=19H 34M 30.90S +/- 0.01S, 2000 V=21.0 +/- 1.0 193430+50252 DEC=50D 25' 23.2" +/- 0.1" 3 4 QSO- GALAXY RA=07H 16M 3.53S +/- 0.01S, 2000 V=20.0 +/- 0.5 071603+47085 DEC=47D 08' 50.1" +/- 0.1" 0 5908( 0) - 07/18/95 18:34 - [ 4] Visit: 01 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 ------------------------------------------------------------------------------------------------------------------------------------ 11 QSO- WFPC2 IMAGE PC1 F555W 1 2S 160140+4316 47 ------------------------------------------------------------------------------------------------------------------------------------ 12 QSO- WFPC2 IMAGE PC1 F555W 1 900S 160140+4316 47 ------------------------------------------------------------------------------------------------------------------------------------ 13 QSO- WFPC2 IMAGE PC1 F814W 1 1000S 160140+4316 47 ------------------------------------------------------------------------------------------------------------------------------------ 5908( 0) - 07/18/95 18:34 - [ 5] Visit: 02 Visit Requirements: CVZ 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 ------------------------------------------------------------------------------------------------------------------------------------ 21 QSO- WFPC2 IMAGE PC1 F555W 1 2S 160913+6532 28 ------------------------------------------------------------------------------------------------------------------------------------ 22 QSO- WFPC2 IMAGE PC1 F555W CR-SPLIT=NO 3 500S 160913+6532 28 ------------------------------------------------------------------------------------------------------------------------------------ 23 QSO- WFPC2 IMAGE PC1 F814W CR-SPLIT=NO 3 800S 160913+6532 28 ------------------------------------------------------------------------------------------------------------------------------------ 5908( 0) - 07/18/95 18:34 - [ 6] Visit: 03 Visit Requirements: On Hold Comments: On hold awaiting Merlin data Additional Comments: On hold awaiting Merlin data Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 31 QSO- WFPC2 IMAGE PC1 F555W 1 2S 193430+5025 23 ------------------------------------------------------------------------------------------------------------------------------------ 32 QSO- WFPC2 IMAGE PC1 F555W 1 900S 193430+5025 23 ------------------------------------------------------------------------------------------------------------------------------------ 33 QSO- WFPC2 IMAGE PC1 F814W 1 1100S 193430+5025 23 ------------------------------------------------------------------------------------------------------------------------------------ 5908( 0) - 07/18/95 18:34 - [ 7] Visit: 04 Visit Requirements: On Hold Comments: On hold awaiting Merlin data Additional Comments: On hold awaiting Merlin data Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 41 QSO- WFPC2 IMAGE PC1 F555W 1 2S 071603+4708 50 ------------------------------------------------------------------------------------------------------------------------------------ 42 QSO- WFPC2 IMAGE PC1 F555W 1 900S 071603+4708 50 ------------------------------------------------------------------------------------------------------------------------------------ 43 QSO- WFPC2 IMAGE PC1 F814W 1 1000S 071603+4708 50 ------------------------------------------------------------------------------------------------------------------------------------ 5908( 0) - 07/18/95 18:34 - [ 8] Summary Form for Proposal 5908 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category Quasars ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements CVZ ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F555W F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names QSO-160140+431647 QSO-160913+653228 QSO-193430+502523 QSO-071603+470850 ------------------------------------------------------------------------------------------------------------------------------------