6632( 4) - 12/22/98 19:04 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6632 Version: 4 Check-in Date: 09-Jan-1997 16:14:37 1.Proposal Title: MORPHOLOGIES OF HIGH--REDSHIFT RADIO GALAXIES ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 6 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: George Miley Leiden Observatory CoI: Huub Rottgering Leiden Observatory N CoI: Rob van Ojik Leiden Observatory N CoI: Laura Pentericci Leiden Observatory N CoI: Duccio Macchetto Space Telescope Science Institute N CoI: Patrick McCarthy Observatories of the CIW N CoI: Wil van Breugel Lawrence Livermore National Lab N CoI: Hyron Spinrad University of California, Berkeley N ------------------------------------------------------------------------------------ 5. Abstract We propose to continue our study of the continuum and Ly Alpha morphologies of 20 high--redshift radio galaxies begun in Cycle 5. Our sample was chosen from 50 candidates to be bright in both continuum and Ly Alpha. The observations would elucidate sub-kiloparsec-scale structures in the target galaxies, allowing study of their alignment and relationships to the associated radio sources. Of particular interest is a comparison between the HST clumpiness and the recently discovered spatially-extended absorption systems in the Ly Alpha profiles., During Cycle 5 we were allocated time to begin the project, with 8 broad-band targets and 3 Ly Alpha LRF test images. The first of these observations show that (i) features of which are difficult to explain by a single simple scattering or starburst model, (ii) a variety of different morphologies, which provide compelling arguments that imaging a larger sample is essential for understanding the processes involved, (iii) our exposure times are well chosen to delineate the morphologies, both in the continuum and Ly Alpha. The images will also be used to provide the most interesting targets for a followup spectroscopic and kinematic study with STIS., The project is providing unique information relevant to the formation and evolution of radio galaxies, to relationships between galaxy and quasar activity and to physical conditions in the early Universe. ------------------------------------------------------------------------------------ 6632( 4) - 12/22/98 19:04 - [ 2] Observations Description ------------------------ noindent Need for Extension of Sample. At the end of Cycle 5 we will have imaged 8 objects in continuum and 3 in Ly Alpha. The diversity in morphologies coupled with the need to disentangle the many effects and various parameters discussed above provide compelling arguments for imaging a sizeable sample of distant radio galaxies with the HST, both in the continuum and in Ly Alpha. Imaging such a sample is also essential to make most efficient use of future HST time. Here we propose completing our sample of 20 objects in the continuum and 10 in Ly Alpha. Our proposed observations can be used to enable the most interesting targets to be selected for a followup spectroscopic and kinematic study with STIS and deep imaging with WFPC2, NIC and the AC. , , noindent Continuum Imaging. We shall carry out continuum imaging of 5 out of our sample of 20 radio galaxies known to have z > 2, R - magnitude < 23.5 and Ly Alpha fluxes > 10^ -15 erg s^ -1cm^-2 . Two of the 5 targets have already been observed in Cycle 5 but need deeper observations (5 and 6 orbits each respectively) and 3 of the targets are new and will be observed each for 2 orbits. Our choice of filter is dictated by three criteria. First bright lines (Ly Alpha) should be excluded from the pass band. Second, the filters should result in as large as possible detected light signal. Third, the rest- wavelengths should be as similar as possible over the redshift range. As a reasonable compromise between these criteria, we shall observe all z < 2.9 galaxies through F606W, the most efficient filter. For the z > 2.9 radio galaxies, Ly Alpha contamination will be avoided by observing through F702W. , * The PC is preferable as a detector than the WFC. Although the signal per pixel will be smaller for the PC, averaging the signal over 4.7 pixels should result in similar sampling to the WFC with very slightly degraded signal to noise. However, we regard the additional spatial resolution provided by the better sampling as a significant advantage. Our targets are all small compared with the field of the PC. , * We request an average of two orbits per target for the continuum imaging. First results of our Cycle 5 observations show that this exposure time for the broad-band imaging is sufficient to delineate the main features of the continuum morphologies. This choice was based on the following considerations. Our Cycle 1 (aberrated) exposures were each of length about 6 x 30m. Both 4C 41.17 and 4C 28.58 contained two or more 0.1" clumps, each of which produced more than 10\% of the total flux from these galaxies (less than 2.5 magnitudes fainter than the integrated galaxy magnitudes). Assume that all the targets have similar ratios of flux in clumpy structures and that we wish to observe galaxies down to integrated R-magnitudes < 23.5 (1.5 magnitudes fainter than 4C 41.17). For a 40m minute exposure through the F606W filter with PC1, a 26th mag clump will produce 564 electrons per 0.1" by 0.1" PSF (60\% of the energy is intercepted within this area). The resultant signal-to-noise per PSF after 2 orbits is about 25. Most of the targets are 0.5 to 1.5 mag brighter than R = 23.5., , Real Time Justification ----------------------- The project is part of a comprehensive study into the nature of distant galaxies, involving ground-based optical (incl. Keck), infrared and radio imaging and optical and IR spectroscopy. Our proposal builds on several years of preparatory ground-based programs. We have access to a huge body of relevant data including:, (i) optical images and spectra (Kitt Peak, La Silla, Tololo, Las Campanas, Lick, La Palma), (ii) Ly Alpha spectral profiles with a resolution of better than 100 km/s. , (iii) 2.2 micron images (UKIRT, Las Campanas), (iv) radio maps of the total intensity and polarisations at several frequencies and resolutions (VLA, MERLIN interferometric array at Jodrell Bank). (e.g. Carilli et al. 1995). These ground-based data (particularly comparable resolution radio maps) will be carefully compared with the HST data. Note that our HST images are comparable in resolution to the best VLA maps, For the first time they allow detailed comparisons between radio and optical morphologies to be made on the kiloparsec scale., (v) We have a large programme with ISO to search for dust in three of our proposed targets and we shall complement this with observations with the SCUBA sub-millimeter bolometer on the UK/NL JCMT., , Some of us have begun a programme to study the targets with the Keck Telescope and we intend to follow up the HST observations spectroscopically with Keck., , One of us (HR) is involved with WFPC2 observations of a complete sample of z~ 1 radio galaxies carried out during Cycle 4. (PI M. Longair). A "low-z" control sample will therefore be available to allow evolutionary effects to be studied., , Two of us are (WvB, GM) are involved with WFPC2 imaging of a similar sample of z > 2 quasars carried out during Cycles 4 and 5. (PI M. Lehnert). Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 6632( 4) - 12/22/98 19:04 - [ 3] Data Distribution Paper Products: Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 6632( 4) - 12/22/98 19:04 - [ 4] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 GAL-1140-26 GALAXY RA=11H 40M 48.4S +/- 1.0S, DEC=- J2000 Z=2.15 V = 21.4 26D 29' 08.0" +/- 1.0" B-V = 0 Comments: FLUXES ARE UNCERTAIN, BUT TARGETS ARE NOT MUCH BRIGHTER. 2 GAL-2106-24 GALAXY RA=21H 06M 58.1S +/- 1.0S, DEC=- J2000 Z=2.49 V = 22.5 24D 05' 11.0" +/- 1.0" B-V = 0 Comments: FLUXES ARE UNCERTAIN, BUT TARGETS ARE NOT MUCH BRIGHTER. 3 GAL-1348+24 GALAXY RA=13H 48M 14.9S +/- 1.0S, J2000 Z=2.91 V = 22.0 DEC=+24D 15' 50.0" +/- 1.0" B-V = 0 Comments: FLUXES ARE UNCERTAIN, BUT TARGETS ARE NOT MUCH BRIGHTER. 4 GAL-1908+72 GALAXY RA=19H 08M 23.7S +/- 1.0S, J2000 Z=3.54 V = 21.5 DEC=+72D 20' 12.0" +/- 1.0" B-V = 0 Comments: FLUXES ARE UNCERTAIN, BUT TARGETS ARE NOT MUCH BRIGHTER. 5 GAL-2144+19 GALAXY RA=21H 44M 07.4S +/- 1.0S, J2000 Z=3.59 V = 21.0 DEC=+19D 29' 15.0" +/- 1.0" B-V = 0 Comments: FLUXES ARE UNCERTAIN, BUT TARGETS ARE NOT MUCH BRIGHTER. 6632( 4) - 12/22/98 19:04 - [ 5] Visit: 01 Visit Priority: Visit Requirements: PCS MODE Fine On Hold Comments: Additional Comments: DO 2 EXPOSURES IN THIS VISIT, ONE IN EACH OF TWO CONSECUTIVE ORBITS. BOTH EXPOSURES SHOULD HAVE THE SAME EXPOSURE TIME UPON LENGTHENING OR SHORTENING, AND THE SECOND SHOULD BE DITHERED FROM THE FIRST BY 11 PC PIXELS. BOTH EXPOSURES SHOULD BE AT THE EXACT SAME ORIENT. BOTH EXPOSURES USE CR-SPLIT=NO IN ORDER TO MAXIMIZE S/N. PCS MODE FINE SHOULD BE USED FOR BOTH. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 GAL-1348+24 WFPC2 IMAGE PC1 F702W CR-SPLIT=NO 1 2400 S POS TARG 0.0, 0.0 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT DEFAULT BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 2 GAL-1348+24 WFPC2 IMAGE PC1 F702W CR-SPLIT=NO 1 2400 S POS TARG 0.506, 0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT POSITION 11 PC PIXELS OFF IN X AND Y FROM BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 6632( 4) - 12/22/98 19:04 - [ 6] Visit: 02 Visit Priority: Visit Requirements: PCS MODE Fine On Hold Comments: Additional Comments: DO 2 EXPOSURES IN THIS VISIT, ONE IN EACH OF TWO CONSECUTIVE ORBITS. BOTH EXPOSURES SHOULD HAVE THE SAME EXPOSURE TIME UPON LENGTHENING OR SHORTENING, AND THE SECOND SHOULD BE DITHERED FROM THE FIRST BY 11 PC PIXELS. BOTH EXPOSURES SHOULD BE AT THE EXACT SAME ORIENT. BOTH EXPOSURES USE CR-SPLIT=NO IN ORDER TO MAXIMIZE S/N. PCS MODE FINE SHOULD BE USED FOR BOTH. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 GAL-1908+72 WFPC2 IMAGE PC1 F702W CR-SPLIT=NO 1 2400 S POS TARG 0.0, 0.0 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT DEFAULT BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 2 GAL-1908+72 WFPC2 IMAGE PC1 F702W CR-SPLIT=NO 1 2400 S POS TARG 0.506, 0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT POSITION 11 PC PIXELS OFF IN X AND Y FROM BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 6632( 4) - 12/22/98 19:04 - [ 7] Visit: 03 Visit Priority: Visit Requirements: PCS MODE Fine On Hold Comments: Additional Comments: DO 2 EXPOSURES IN THIS VISIT, ONE IN EACH OF TWO CONSECUTIVE ORBITS. BOTH EXPOSURES SHOULD HAVE THE SAME EXPOSURE TIME UPON LENGTHENING OR SHORTENING, AND THE SECOND SHOULD BE DITHERED FROM THE FIRST BY 11 PC PIXELS. BOTH EXPOSURES SHOULD BE AT THE EXACT SAME ORIENT. BOTH EXPOSURES USE CR-SPLIT=NO IN ORDER TO MAXIMIZE S/N. PCS MODE FINE SHOULD BE USED FOR BOTH. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 GAL-2144+19 WFPC2 IMAGE PC1 F702W CR-SPLIT=NO 1 2400 S POS TARG 0.0, 0.0 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT DEFAULT BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 2 GAL-2144+19 WFPC2 IMAGE PC1 F702W CR-SPLIT=NO 1 2400 S POS TARG 0.506, 0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT POSITION 11 PC PIXELS OFF IN X AND Y FROM BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 6632( 4) - 12/22/98 19:04 - [ 8] Visit: 04 Visit Priority: Visit Requirements: PCS MODE Fine ORIENT 273.801292D TO 273.801292D On Hold Comments: Additional Comments: DO 5 EXPOSURES IN THIS VISIT, IN CONSECUTIVE ORBITS. EXPOSURES SHOULD HAVE THE SAME EXPOSURE TIME UPON LENGTHENING OR SHORTENING, AND THEY SHOULD BE DITHERED FROM EACH OTHER BY 11 PC PIXELS. THERE IS ALSO A ZERO-SHIFT IN POSITION COMPARED WITH CYCLE 5. EXPOSURES SHOULD BE AT THE EXACT SAME ORIENT AS CYCLE 5. EXPOSURES USE CR-SPLIT=NO IN ORDER TO MAXIMIZE S/N. PCS MODE FINE SHOULD BE USED. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 GAL-1140-26 WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 1 2400 S POS TARG 0.506, 0.0 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT DEFAULT BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 2 GAL-1140-26 WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 1 2400 S POS TARG 0.0, 0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT POSITION 11 PC PIXELS OFF IN X AND Y FROM BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 3 GAL-1140-26 WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 1 2400 S POS TARG -0.506,-0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT DEFAULT BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 4 GAL-1140-26 WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 1 2400 S POS TARG -0.506,+0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT POSITION 11 PC PIXELS OFF IN X AND Y FROM BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 5 GAL-1140-26 WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 1 2400 S POS TARG +0.506,-0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT POSITION 11 PC PIXELS OFF IN X AND Y FROM BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 6632( 4) - 12/22/98 19:04 - [ 9] Visit: 05 Visit Priority: Visit Requirements: PCS MODE Fine ORIENT 55.51840D TO 55.51840D On Hold Comments: Additional Comments: ORIENT IS CHOSEN TO AVOID DIFFRACTION SPIKES OF FOREGROUND STAR. HENCE ALLOWABLE ORIENTS ARE ALSO EVERY 90 DEG FROM THAT SPECIFIED. HENCE, ORIENT 55D TO 90D OR ORIENT 145D TO 180D OR ORIENT 235D TO 270D OR ORIENT 325D TO 360D DO 4 EXPOSURES IN THIS VISIT, IN CONSECUTIVE ORBITS. EXPOSURES SHOULD HAVE THE SAME EXPOSURE TIME UPON LENGTHENING OR SHORTENING, AND THEY SHOULD BE DITHERED FROM EACH OTHER BY 11 PC PIXELS. THERE IS ALSO A ZERO-SHIFT IN POSITION COMPARED TO CYCLE 5. EXPOSURES SHOULD BE AT THE EXACT SAME ORIENT. EXPOSURES USE CR-SPLIT=NO IN ORDER TO MAXIMIZE S/N. PCS MOD E FINE SHOULD BE USED. ORIENT IS CHOSEN TO AVOID DIFFRACTION SPIKES FROM FOREGROUND STAR. SPECIFIED ABSOLUTE ORIENT IS TO MATCH THAT OF OUR DATA FROM THE PREVIOUS CYCLE. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 GAL-2106-24 WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 1 2400 S POS TARG +0.506,-0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT DEFAULT BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 2 GAL-2106-24 WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 1 2400 S POS TARG 0.506, 0.0 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT POSITION 11 PC PIXELS OFF IN X AND Y FROM BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 3 GAL-2106-24 WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 1 2400 S POS TARG -0.506,+0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT DEFAULT BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 4 GAL-2106-24 WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 1 2400 S POS TARG -0.506,-0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT Comments: DO SINGLE NON-CR-SPLIT EXPOSURE AT POSITION 11 PC PIXELS OFF IN X AND Y FROM BEST CENTER OF PC1. ------------------------------------------------------------------------------------------------------------------------------------ 6632( 4) - 12/22/98 19:04 - [ 10] Summary Form for Proposal 6632 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures PC1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PCS MODE Fine POS TARG 0.0, 0.0 MAX DUR 3000S MIN DUR 1800S END ORBIT POS TARG 0.506, 0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT PCS MODE Fine ORIENT 273.801292D TO 273.801292D POS TARG 0.506, 0.0 MAX DUR 3000S MIN DUR 1800S END ORBIT POS TARG 0.0, 0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT POS TARG -0.506,-0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT POS TARG -0.506,+0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT POS TARG +0.506,-0.506 MAX DUR 3000S MIN DUR 1800S END ORBIT PCS MODE Fine ORIENT 55.51840D TO 55.51840D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F702W F606W ------------------------------------------------------------------------------------------------------------------------------------ Target Names GAL-1348+24 GAL-1908+72 GAL-2144+19 GAL-1140-26 GAL-2106-24 ------------------------------------------------------------------------------------------------------------------------------------