Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 1052c Report Date: 09-May-96:16:05 Version: ********** Check-in Date: ********** 1.Proposal Title: GLOBULAR CLUSTER CORE STRUCTURE AND DYNAMICS (FOS 36) -- CYCLE 0 ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID STELLAR POPULATIONS GTO/FOS Sub Category ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Ralph Bohlin SPACE TELESCOPE SCIENCE INST USA (301) 338-4804 ------------------------------------------------------------------------------------ 7. Abstract Obtain data on the stellar populations in the central cores of globular clusters. Clusters with and without central unresolved cusps, and with and without central X- ray sources will be observed. Spectra will be obtained at the center of the UV brightness, and at a distance within about one core radius. We might expect these spectra to differ; massive objects formed in collisions may produce unexpected spectral features, as well as relatively intense UV radiation in the central core. ------------------------------------------------------------------------------------ 8. Scientific Key Words: GLOBULAR CLUSTER ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 6.58 par: 0 10. Num targs pri: 24 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: FOS WF/PC ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 1052c PI: Ralph Bohlin Proposal Title: GLOBULAR CLUSTER CORE STRUCTURE AND DYNAMICS (FOS 36) -- CYCLE 0 ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Edward Beaver UC, SAN DIEGO USA E. Margaret Burbidge UC, SAN DIEGO USA Bruce Margon WASHINGTON, UNIVERSITY OF USA Lyman Spitzer Jr. PRINCETON UNIVERSITY USA J. Roger P. Angel ARIZONA, UNIVERSITY OF USA Frank Bartko APPLIED RESEARCH CORPORATION USA Arthur F. Davidsen JOHNS HOPKINS UNIVERSITY USA Richard J. Harms APPLIED RESEARCH CORPORATION USA Ralph Bohlin SPACE TELESCOPE SCIENCE USA INSTITUTE Holland C. Ford SPACE TELESCOPE SCIENCE USA INSTITUTE ------------------------------------------------------------------------------------ 3. Description of proposed observations. Since the globular clusters are faint, use the low dispersion G160L and the Prism on the Blueside. Use the lower 0.3" aperture. 20s DARK exposures are especially useful for these faint targets; take DARKS before and after each exposure. The PC images are essential for target acquisition for the spectra. Offset the PC pointing to place the center of the G.C. (quoted coordinates) 10" off the pyramid along the centerline of the best CCD chip. We require two months between delivery of the PC images and the final specification of the FOS pointings. FOS target acquisition in mode III assumes that the PC is calibrated for astrometry to 0.03". PC filters are F230W, F336W, and F547M. Cycle 0 Exp: 10, 16 Cycle 1 Exp: 10.9-12 Cycle 2 Exp: 13-15, 16.9-28 ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. The SV prerequisite programs for all FOS observations in this program are: Prop ID 2195 FOS Target Acquisition Tests - All observations Prop ID 1317 Int./Ext. Wavelength Offsets - 1st target Prop ID 1318 Spectral Flat Fields - 1st target Prop ID 1320 Absolute Spectrophotometry - 1st visit of bright targets All WF/PC imaging with a center wavelength blueward of 5000 Angstroms requires UV flood ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. DARK may or may not be necessary, but if incidents ever occur that raise the dark level, we will have no ex-post facto way of validating any continuum spectrum without a DARK measure at the time of each observation. ------------------------------------------------------------------------------------ 12. This program does not become a viable scientific investigation until 5 of the 6 globular clusters have been observed by both the WFPC and FOS. No data should be made public sooner than 1 year after that time. ------------------------------------------------------------------------------------ 13. Use FOS spectra to investigate the structure and dynamics of the cores of globular clusters. Spectra on and just off the core will be obtained for clusters with and without cusps and with and without central x-ray sources. ------------------------------------------------------------------------------------ 11. Address Information Page 3 Name: RALPH BOHLIN Category: PI Institution: SPACE TELESCOPE SCIENCE INSTITUTE Address: HOMEWOOD CAMPUS City: BALTIMORE State: MD Zip Code: 21218 Country: USA Telephone: (301) 338-4804 Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 1052c [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 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 NGC1851 GLOBULAR CLUSTER WITH RA=5H 12M 28.03S +/- 0.7", 1950 1 F(1500)=2.5 E-15 CORE RADIUS=5.9" DEC=-40D 06' 11.4" +/- 0.7" 2 SURF(V)=14.7 ------------------------------------------------------------------------------------------------------------------------------------ 5 NGC6205 M13 G.C. WITH CORE=46" RA=16H 39M 53.28S +/- 1", 1950 1 SURF(V)=16.7 DEC=+36D 33' 11.5" +/- 1" ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 1052c [ 5] ------------------------------------------------------------------------------------------------------------------------------------ 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 DEFINE # PC IMAGE ALL F230W CR-SPLIT=0.1 1 250S # PC1 PRE-FLASH=YES ------------------------------------------------------------------------------------------------------------------------------------ 2 DEFINE # PC IMAGE ALL F336W CR-SPLIT=0.1 1 130S # GROUP 2-3 WITHIN PC2 PRE-FLASH=YES 15D ------------------------------------------------------------------------------------------------------------------------------------ 3 ^ # ^ ^ ^ F547M ^ ^ 100S # Comments: THE PC ACQUISITION ASSUMES AN ASTROMETRIC CALIBRATION OF THE PC WITH 0".03 ACCURACY. ------------------------------------------------------------------------------------------------------------------------------------ 10 USE PC2 NGC1851 1 GUID TOL 0.020" CYCLE 0 ------------------------------------------------------------------------------------------------------------------------------------ 16 USE PC2 NGC6205 2 GUID TOL 0.020" CYCLE 0 ------------------------------------------------------------------------------------------------------------------------------------ 17 USE PC1 NGC1851 1 GUID TOL 0.020" CYCLE 0 ------------------------------------------------------------------------------------------------------------------------------------ 18 USE PC1 NGC6205 2 GUID TOL 0.020" CYCLE 0 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 1052c [ 6] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations PC ^ ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ^ ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=0.1 PRE-FLASH=YES ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GTO/FOS ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 6.58 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category STELLAR POPULATIONS ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GROUP 2-3 WITHIN 15D; GUID TOL 0.020"; CYCLE 0 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F230W F336W F547M ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC1851 NGC6205 M13 ------------------------------------------------------------------------------------------------------------------------------------