5990( 7) - 01/15/96 08:57 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 5990 Version: 7 Check-in Date: 15-Jan-1996 08:51:12 1.Proposal Title: Globular Clusters in Fornax Galaxies ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle Galaxies & Clusters GO 5 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Carl Grillmair University of California Observatories/Lick Observatory CoI: Duncan Forbes University of California N Observatories/Lick Observatory CoI: Jean Brodie University of California N Observatories/Lick Observatory CoI: Kenneth Freeman Mount Stromlo and Siding Springs N Observatories CoI: Rebecca Elson University of Cambridge N ------------------------------------------------------------------------------------ 6. Abstract Outside the Local Group, the nearest concentration of large globular cluster systems is in the Fornax cluster. Based on differences in host galaxy morphologies, we expect that these globular cluster systems should show differences which would bear on our understanding of the role of mergers, tidal encounters, cooling flows, and initial collapse in the formation and evolution of globular clusters and cluster galaxies. We propose to obtain WFPC2 images of the cores of the cD galaxy NGC 1399, the merger candidate NGC 1316, and two more normal ellipticals. The superior resolution of WFPC2 will permit detection and photometry of globular clusters in the bright and crowded centers of our sample galaxies as well as enable improved discrimination between globular clusters and background galaxies. We will measure colors, surface densities, and structural parameters of these globulars and, by comparing with control fields and ground-based imaging, measure system core radii, look for radial color gradients, and search for young, blue clusters of the type discovered in NGC 1275. We will also determine globular cluster luminosity functions to about 3 magnitudes past the expected luminosity peak, enabling us to i) test the ``universality'' of globular cluster luminosity functions, ii) look for environmental influences, and iii) improve estimates for the distance to the Fornax cluster. Followup spectroscopy of young or otherwise interesting objects will be carried out using the Keck telescope. ------------------------------------------------------------------------------------ 5990( 7) - 01/15/96 08:57 - [ 2] Observations Description ------------------------ We propose to obtain WFPC2 images in two colors of the central regions of 4 elliptical galaxies in the Fornax cluster with known globular cluster systems. We will also observe 2 control fields in an identical manner for comparison and calibration purposes. We would require integration times sufficient to give us reasonable photometry (+/- .1 mag) down to I ~ 26. Based on work in progress on WFPC2 images of globular clusters in M31 (Grillmair et al. 1995, in preparation), we would require 30 minutes of integration time in F814W to reach this level. Using the filter/telescope efficiencies given in the WFPC2 Handbook and assuming a G0 spectrum for globular clusters, we calulate that we can achieve a similar S/N using F450W in ~ 90 minutes. For NGC 1399 we propose 3*10 minute exposures in F814W during the first orbit, and 4*22 minute exposures in F450W during the subsequent two orbits. The two background fields will be observed in exactly the same manner. Examination of deconvolved WFPC1 images of NGC 1316 reveal that the core of the galaxy would be saturated in F814W at the exposure levels used above. We would consequently split our F814W observations of this galaxy into one 4 minute exposure followed by 2*13 minute exposures to permit recovery of information in the central few pixels. As the central surface brightnesses of NGC 1379 and NGC 1404 are poorly known, we will observe these galaxies using the same strategy used for NGC 1316. This yields a total of 45 exposures over 18 primary orbits. Real Time Justification ----------------------- None. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: , ------------------------------------------------------------------------------------ 5990( 7) - 01/15/96 08:57 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC1316 GALAXY, Radio Galaxy, RA = 3H 22M 41.8S +/- 0.2S, DEC 2000 V = SURF(V) = 13.4+/-0.2 Interacting Galaxy = -37D 12' 29.8" +/- 2.0" +1793 B-V = 0.93 U-B = 0.47 Comments: Colors from RC3, surface brightness from WFPC1. 2 NGC1399 GALAXY, Elliptical RA = 3H 38M 29.0S +/- 0.2S, DEC 2000 V = SURF(V) = 15.9+/-0.2 = -35D 27' 0.5" +/- 2.0" +1447 B-V = 0.98 U-B = 0.56 Comments: Surface brightness from WFPC1. 3 NGC1379 GALAXY, Elliptical RA = 3H 36M 3.89S +/- 0.2S, DEC 2000 V = SURF(V) = 13+/-1.0 = -35D 26' 26" +/- 2.0" +1376 B-V = 0.91 U-B = 0.41 Comments: Surface brightness extrapolated from Schombert's profile. 4 NGC1404 GALAXY, Elliptical RA = 3H 38M 51.7S +/- 0.2S, DEC 2000 V = SURF(V) = 11.0+/-1.0 = -35D 35' 36" +/- 2.0" +1929 B-V = 0.99 U-B = 0.57 Comments: Surface brightness extrapolated from Schombert's profile. 5 FIELD-0338- CLUSTER OF GALAXIES, RA = 3H 37M 57.08S +/- 0.01S, 2000 3523 Blank Sky DEC = -35D 21' 54.5" +/- 0.01" 6 FIELD-0336- CLUSTER OF GALAXIES, RA = 3H 36M 2.75S +/- 0.01S, DEC 2000 3645 Blank Sky = -36D 45' 54.0" +/- 0.01" 5990( 7) - 01/15/96 08:57 - [ 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC1316 WFPC2 IMAGE PC1-FIX F814W 1 260S POS TARG +0.5005,+0.5005 ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC1316 WFPC2 IMAGE PC1-FIX F814W 1 1600S ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC1316 WFPC2 IMAGE PC1-FIX F450W 1 2600S ------------------------------------------------------------------------------------------------------------------------------------ 4 NGC1316 WFPC2 IMAGE PC1-FIX F450W CR- 1 1100S POS TARG +0.5005,+0.5005 SPLIT=.5454545 ------------------------------------------------------------------------------------------------------------------------------------ 5 NGC1316 WFPC2 IMAGE PC1-FIX F450W CR-SPLIT=NO 1 1400S POS TARG +0.5005,+0.5005 ------------------------------------------------------------------------------------------------------------------------------------ 5990( 7) - 01/15/96 08:57 - [ 5] Visit: 02 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC1399 WFPC2 IMAGE PC1-FIX F814W 1 1200S ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC1399 WFPC2 IMAGE PC1-FIX F814W CR-SPLIT=NO 1 600S POS TARG +0.5005,+0.5005 ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC1399 WFPC2 IMAGE PC1-FIX F450W 1 2600S POS TARG +0.5005,+0.5005 ------------------------------------------------------------------------------------------------------------------------------------ 4 NGC1399 WFPC2 IMAGE PC1-FIX F450W 1 2600S ------------------------------------------------------------------------------------------------------------------------------------ 5990( 7) - 01/15/96 08:57 - [ 6] Visit: 03 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC1379 WFPC2 IMAGE PC1-FIX F814W 1 260S POS TARG +0.5005,+0.5005 ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC1379 WFPC2 IMAGE PC1-FIX F814W 1 1600S ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC1379 WFPC2 IMAGE PC1-FIX F450W 1 2600S ------------------------------------------------------------------------------------------------------------------------------------ 4 NGC1379 WFPC2 IMAGE PC1-FIX F450W CR- 1 1100S POS TARG +0.5005,+0.5005 SPLIT=.5454545 ------------------------------------------------------------------------------------------------------------------------------------ 5 NGC1379 WFPC2 IMAGE PC1-FIX F450W CR-SPLIT=NO 1 1400S POS TARG +0.5005,+0.5005 ------------------------------------------------------------------------------------------------------------------------------------ 5990( 7) - 01/15/96 08:57 - [ 7] Visit: 04 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC1404 WFPC2 IMAGE PC1-FIX F814W 1 260S POS TARG +0.5005,+0.5005 ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC1404 WFPC2 IMAGE PC1-FIX F814W 1 1600S ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC1404 WFPC2 IMAGE PC1-FIX F450W 1 2600S ------------------------------------------------------------------------------------------------------------------------------------ 4 NGC1404 WFPC2 IMAGE PC1-FIX F450W CR- 1 1100S POS TARG +0.5005,+0.5005 SPLIT=.5454545 ------------------------------------------------------------------------------------------------------------------------------------ 5 NGC1404 WFPC2 IMAGE PC1-FIX F450W CR-SPLIT=NO 1 1400S POS TARG +0.5005,+0.5005 ------------------------------------------------------------------------------------------------------------------------------------ 5990( 7) - 01/15/96 08:57 - [ 8] Visit: 05 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 FIELD-0338- WFPC2 IMAGE PC1-FIX F814W 1 1200S 3523 ------------------------------------------------------------------------------------------------------------------------------------ 2 FIELD-0338- WFPC2 IMAGE PC1-FIX F814W CR-SPLIT=NO 1 600S POS TARG +0.5005,+0.5005 3523 ------------------------------------------------------------------------------------------------------------------------------------ 3 FIELD-0338- WFPC2 IMAGE PC1-FIX F450W 1 2600S POS TARG +0.5005,+0.5005 3523 ------------------------------------------------------------------------------------------------------------------------------------ 4 FIELD-0338- WFPC2 IMAGE PC1-FIX F450W 1 2600S 3523 ------------------------------------------------------------------------------------------------------------------------------------ 5990( 7) - 01/15/96 08:57 - [ 9] Visit: 06 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 FIELD-0336- WFPC2 IMAGE PC1-FIX F814W 1 1200S 3645 ------------------------------------------------------------------------------------------------------------------------------------ 2 FIELD-0336- WFPC2 IMAGE PC1-FIX F814W CR-SPLIT=NO 1 600S POS TARG +0.5005,+0.5005 3645 ------------------------------------------------------------------------------------------------------------------------------------ 3 FIELD-0336- WFPC2 IMAGE PC1-FIX F450W 1 2600S POS TARG +0.5005,+0.5005 3645 ------------------------------------------------------------------------------------------------------------------------------------ 4 FIELD-0336- WFPC2 IMAGE PC1-FIX F450W 1 2600S 3645 ------------------------------------------------------------------------------------------------------------------------------------ 5990( 7) - 01/15/96 08:57 - [ 10] Summary Form for Proposal 5990 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=.5454545 CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category Galaxies & Clusters ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements POS TARG +0.5005,+0.5005 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F814W F450W ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC1316 NGC1399 NGC1379 NGC1404 FIELD-0338-3523 FIELD-0336-3645 ------------------------------------------------------------------------------------------------------------------------------------