8195( 3) - 02/18/99 11:03 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8195 Version: 3 Check-in Date: 18-Feb-1999 11:03:05 1.Proposal Title: The Stellar Halo and the Metallicity Distribution Function in the Giant Elliptical NGC 5128 ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 8 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Gretchen Harris University of Waterloo CoI: Dr. William Harris McMaster University N ------------------------------------------------------------------------------------ 5. Abstract We propose to measure the metallicity distribution function (MDF) of the halo stars in the nearby (d ~ 3.9Mpc) giant elliptical galaxy NGC 5128 by direct (V, I) color- magnitude photometry of its old red-giant stars. Because NGC 5128 is 2 magnitudes closer than any other giant E galaxy, it gives us a unique opportunity to study the enrichment history at a level of detail that is impossible for any other such galaxy. In Cycle 8, we will measure a very remote field at 35 kpc, and a second one in the inner halo at 7 kpc. At the distance of NGC 5128, the photometric limits of the WFPC2 camera reach almost 3 magnitudes in I down the red giant branch, allowing the construction of an accurate MDF. Combined with our Cycle 5 20-kpc field, the three halo fields will allow us to study the MDF and metallicity gradient through the halo, and connect these to enrichment history models. ------------------------------------------------------------------------------------ Observations Description ------------------------ In each of the two target fields we will use 7 orbits in V (F606W) and 5 orbits in I (F814W). Dithered positions will be used to reconstruct final images with increased spatial resolution and improved cosmetics. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 8195( 3) - 02/18/99 11:03 - [ 2] Data Distribution Paper Products: NO Media: ELECTRONIC Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 8195( 3) - 02/18/99 11:03 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC5128- GALAXY, ELLIPTICAL, RA=13H 24M 53.27S +/- 2", DEC=- J2000 V=547 V = 26.0+/-0.1 INNERP1 HALO 43D 4' 35" +/- 2" V-I = 2.0+/-1.0 Comments: Flux and color correspond to brightest halo stars in NGC5128 2 NGC5128- GALAXY, ELLIPTICAL, XI-OFF=0.5"+/- 0.05", ETA- J2000 V=547 V = 26.0+/-0.1 INNERP2 HALO OFF=0.25"+/- 0.05", FROM 1 V-I = 2.0+/-1.0 Comments: Flux and color correspond to brightest halo stars in NGC5128 3 NGC5128- GALAXY, ELLIPTICAL, XI-OFF=0.75"+/- 0.05", ETA- J2000 V=547 V = 26.0+/-0.1 INNERP3 HALO OFF=0.75"+/- 0.05", FROM 1 V-I = 2.0+/-1.0 Comments: Flux and color correspond to brightest halo stars in NGC5128 4 NGC5128- GALAXY, ELLIPTICAL, XI-OFF=0.25"+/- 0.05", ETA- J2000 V=547 V = 26.0+/-0.1 INNERP4 HALO OFF=0.5"+/- 0.05", FROM 1 V-I = 2.0+/-1.0 Comments: Flux and color correspond to brightest halo stars in NGC5128 5 NGC5128- GALAXY, ELLIPTICAL, RA=13H 25M 18.00S +/- 2", DEC=- J2000 V=547 V = 26.0+/-0.1 OUTERP1 HALO 43D 28' 15" +/- 2" V-I = 2.0+/-1.0 Comments: Flux and color correspond to brightest halo stars in NGC5128 6 NGC5128- GALAXY, ELLIPTICAL, XI-OFF=0.5"+/- 0.05", ETA- J2000 V=547 V = 26.0+/-0.1 OUTERP2 HALO OFF=0.25"+/- 0.05", FROM 5 V-I = 2.0+/-1.0 Comments: Flux and color correspond to brightest halo stars in NGC5128 7 NGC5128- GALAXY, ELLIPTICAL, XI-OFF=0.75"+/- 0.05", ETA- J2000 V=547 V = 26.0+/-0.1 OUTERP3 HALO OFF=0.75"+/- 0.05", FROM 5 V-I = 2.0+/-1.0 Comments: Flux and color correspond to brightest halo stars in NGC5128 8 NGC5128- GALAXY, ELLIPTICAL, XI-OFF=0.25"+/- 0.05", ETA- J2000 V=547 V = 26.0+/-0.1 OUTERP4 HALO OFF=0.5"+/- 0.05", FROM 5 V-I = 2.0+/-1.0 Comments: Flux and color correspond to brightest halo stars in NGC5128 8195( 3) - 02/18/99 11:03 - [ 4] Visit: 01 Visit Priority: Visit Requirements: ORIENT 30D TO 100D On Hold Comments: Additional Comments: U3 orientation to avoid bright star SE of program field Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 11 NGC5128-INN WFPC2 IMAGE PC1 F814W CR-SPLIT=NO 2 1200 S ERP1 ------------------------------------------------------------------------------------------------------------------------------------ 12 NGC5128-INN WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 4 1200 S EXPAND ERP1 ------------------------------------------------------------------------------------------------------------------------------------ 8195( 3) - 02/18/99 11:03 - [ 5] Visit: 02 Visit Priority: Visit Requirements: SAME ORIENT AS 01 On Hold Comments: Additional Comments: U3 orientation to avoid bright star SE of the program field Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 21 NGC5128-INN WFPC2 IMAGE PC1 F814W CR-SPLIT=NO 2 1200 S ERP2 ------------------------------------------------------------------------------------------------------------------------------------ 22 NGC5128-INN WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 4 1200 S EXPAND ERP2 ------------------------------------------------------------------------------------------------------------------------------------ 8195( 3) - 02/18/99 11:03 - [ 6] Visit: 03 Visit Priority: Visit Requirements: SAME ORIENT AS 01 On Hold Comments: Additional Comments: U3 orientation to avoid bright star SE of the program field Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 31 NGC5128-INN WFPC2 IMAGE PC1 F814W CR-SPLIT=NO 2 1200 S ERP3 ------------------------------------------------------------------------------------------------------------------------------------ 32 NGC5128-INN WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 4 1200 S EXPAND ERP3 ------------------------------------------------------------------------------------------------------------------------------------ 8195( 3) - 02/18/99 11:03 - [ 7] Visit: 04 Visit Priority: Visit Requirements: SAME ORIENT AS 01 On Hold Comments: Additional Comments: U3 orientation to avoid bright star SE of the program field Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 41 NGC5128-INN WFPC2 IMAGE PC1 F814W CR-SPLIT=NO 4 1200 S ERP4 ------------------------------------------------------------------------------------------------------------------------------------ 43 NGC5128-INN WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 2 1200 S EXPAND ERP4 ------------------------------------------------------------------------------------------------------------------------------------ 8195( 3) - 02/18/99 11:03 - [ 8] Visit: 05 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Any ORIENTation for visit 5 is acceptable, but visits 6, 7 , 8 must keep the same orientation as visit 5 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 51 NGC5128-OUT WFPC2 IMAGE PC1 F814W CR-SPLIT=NO 2 1200 S ERP1 ------------------------------------------------------------------------------------------------------------------------------------ 52 NGC5128-OUT WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 4 1200 S EXPAND ERP1 ------------------------------------------------------------------------------------------------------------------------------------ 8195( 3) - 02/18/99 11:03 - [ 9] Visit: 06 Visit Priority: Visit Requirements: SAME ORIENT AS 05 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 ------------------------------------------------------------------------------------------------------------------------------------ 61 NGC5128-OUT WFPC2 IMAGE PC1 F814W CR-SPLIT=NO 2 1200 S ERP2 ------------------------------------------------------------------------------------------------------------------------------------ 62 NGC5128-OUT WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 4 1200 S EXPAND ERP2 ------------------------------------------------------------------------------------------------------------------------------------ 8195( 3) - 02/18/99 11:03 - [ 10] Visit: 07 Visit Priority: Visit Requirements: SAME ORIENT AS 05 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 ------------------------------------------------------------------------------------------------------------------------------------ 71 NGC5128-OUT WFPC2 IMAGE PC1 F814W CR-SPLIT=NO 2 1200 S ERP3 ------------------------------------------------------------------------------------------------------------------------------------ 72 NGC5128-OUT WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 4 1200 S EXPAND ERP3 ------------------------------------------------------------------------------------------------------------------------------------ 8195( 3) - 02/18/99 11:03 - [ 11] Visit: 08 Visit Priority: Visit Requirements: SAME ORIENT AS 05 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 ------------------------------------------------------------------------------------------------------------------------------------ 81 NGC5128-OUT WFPC2 IMAGE PC1 F814W CR-SPLIT=NO 4 1200 S EXPAND ERP4 ------------------------------------------------------------------------------------------------------------------------------------ 82 NGC5128-OUT WFPC2 IMAGE PC1 F606W CR-SPLIT=NO 2 1200 S EXPAND ERP4 ------------------------------------------------------------------------------------------------------------------------------------ 8195( 3) - 02/18/99 11:03 - [ 12] Summary Form for Proposal 8195 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures PC1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 30D TO 100D EXPAND SAME ORIENT AS 01 SAME ORIENT AS 05 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F814W F606W ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC5128-INNERP1 NGC5128-INNERP2 NGC5128-INNERP3 NGC5128-INNERP4 NGC5128-OUTERP1 NGC5128-OUTERP2 NGC5128-OUTERP3 NGC5128-OUTERP4 ------------------------------------------------------------------------------------------------------------------------------------