!   $Id: 5342,v 12.1 1994/07/27 16:51:47 pepsa Exp $
!File 5342.prop

COVERPAGE:

  TITLE_1: UV Imaging of Intermediate-age Magellanic Cloud Clusters: 
  TITLE_2: Hot Stellar Populations in Composite Stellar Systems                                        
  SCI_CAT: Cool Stars
  SCI_SUBCAT: Old Clusters
  PROPOSAL_FOR: GO

  LONGTERM: 1
  LARGE_PROJ:
  KEY_PROJ:
  TARG_OF_OPP:

  PI_FNAME: Wendy
  PI_LNAME: Freedman

  PI_INST: Observatories of the CIW
  PI_COUNTRY: USA
  PI_PHONE: 818 304-0204

  HOURS_PRI: 3.95
  HOURS_PAR: 0.00

  SC_TIME: 6.91

  NUM_PRI: 6
  NUM_PAR: 0

  WF_PC: Y

ABSTRACT:

LINE_1: Hot stars were first recognized to be an important component of
LINE_2: galactic spheroids with early vacuum ultraviolet observations of
LINE_3: ellipticals and spiral bulges that were made with OAO.  Now, 20 years
LINE_4: later, we still do not have a full understanding of the VUV evolution
LINE_5: of intermediate and old age stellar populations.  Using the WFPC2, we
LINE_6: therefore propose to undertake an ultraviolet survey of a sample of
LINE_7: star clusters spanning a range in age in the Large Magellanic Cloud.
LINE_8: The objective of this investigation is to determine the nature of the
LINE_9: hot stellar components in rich, intermediate-to-old age LMC clusters.
LINE_10: Ground-based optical/IR studies suggest the presence of short-lived hot
LINE_11: horizontal branch and post-asymptotic giant branch stars in these
LINE_12: clusters but detailed characterizations of the stars require the
LINE_13: ultraviolet capability of HST.  In this effort we will be aided by the
LINE_14: absence of red leaks in the WFPC2 Woods filter and very high angular
LINE_15: resolution of the HST.  Although old star clusters in the Galaxy and
LINE_16: M31 are, and will be, the subjects of intense investigation by HST, OUR
LINE_17: SURVEY WILL BE THE FIRST OF ITS KIND FOR POPULATIONS OF INTERMEDIATE
LINE_18: AGE.  Such systems are critical for interpreting the spectra and colors
LINE_19: of high redshift galaxies, and will provide important support to these
LINE_20: studies.  

GENERAL_FORM_PROPOSERS:

  LNAME: Freedman
  FNAME: Wendy
  INST: Observatories of the CIW
  COUNTRY: USA
  ESA:

  LNAME: Gallagher
  FNAME: John
  MI: S
  INST: University of Wisconsin
  COUNTRY: USA
  ESA:

GENERAL_FORM_ADDRESS:

  LNAME: Freedman
  FNAME: Wendy
  CATEGORY: PI
  INST: Observatories of the CIW
  ADDR_1: Carnegie Observatories
  ADDR_2: 813 Santa Barbara St.
  CITY: Pasadena
  STATE: CA
  ZIP: 91101
  COUNTRY: USA
  PHONE: 818 304-0204

  LNAME: Gallagher
  FNAME: John
  MI: S
  INST: University of Wisconsin
  ADDR_1: Department of Astronomy
  ADDR_2: 475 North Charter St
  CITY: Madison
  STATE: WI
  ZIP: 53706
  COUNTRY: USA
  PHONE: 608 262-3071

GENERAL_FORM_TEXT:    

QUESTION: 3
SECTION: 1
LINE_1: We propose to use the new WFPC2 with the Woods F160W VUV filter
LINE_2: to obtain VUV and the F336W for NUV imaging of 6 rich LMC star clusters
LINE_3: with ages of 0.1-10 Gyr.  This filter pair provides a good UV color
LINE_4: baseline.  In an exposure of 1400 -1800s the Woods filter will reach
LINE_5: m(1600)=20 with a SNR=30; so we have sufficient sensitivity to explore
LINE_6: much of the LMC VUV luminosity function with an efficient series of
LINE_7: exposures.

FIXED_TARGETS:          

  TARGNUM: 1
  NAME_1: NGC1783
  DESCR_1: D,202
  POS_1: RA = 04h 59m 00s +/- 3",
  POS_2: Dec = -66d 03' 30" +/- 3" 
  EQUINOX: 1950

  TARGNUM: 2
  NAME_1: NGC1856
  DESCR_1: D,202
  POS_1: RA  =  05h 09m 47s +/- 3",
  POS_2: Dec = -69d 11' 18" +/- 3"
  EQUINOX: 1950

  TARGNUM: 3
  NAME_1: NGC1835
  DESCR_1: D,202
  POS_1: RA  =  05h 05m 25s +/- 3",
  POS_2: Dec = -69d 28' 12" +/- 3" 
  EQUINOX: 1950

  TARGNUM: 4
  NAME_1: NGC1978
  DESCR_1: D,202
  POS_1: RA  =  06h 11m 47s +/- 3",
  POS_2: Dec = -69d 07' 00" +/- 3",
  POS_3: PLATE-ID = 06B0
  EQUINOX: 1950
  COMMENT_1: THIS PLATE IS USED BY SPSS FOR
  COMMENT_2: GUIDE STAR ACQUISITION.

  TARGNUM: 5
  NAME_1: NGC1866
  DESCR_1: D,202
  POS_1: RA  =  05h 13m 29s +/- 3",
  POS_2: Dec = -65d 31' 18" +/- 3"
  EQUINOX: 1950

  TARGNUM: 6
  NAME_1: NGC2134
  DESCR_1: D,202
  POS_1: RA  =  05h 28m 22s +/- 3",
  POS_2: Dec = -66d 16' 00" +/- 3",
  POS_3: PLATE-ID = 06B0
  EQUINOX: 1950
  COMMENT_1: THIS PLATE IS USED BY SPSS FOR
  COMMENT_2: GUIDE STAR ACQUISITION.

EXPOSURE_LOGSHEET:	

  LINENUM:  1		
  SEQUENCE_1: DEFINE
  SEQUENCE_2: F160W
  TARGNAME: #
  CONFIG: WFPC2
  OPMODE: IMAGE
  APERTURE: #
  SP_ELEMENT: F160BW
  NUM_EXP: 1
  TIME_PER_EXP: 1400s
  PARAM_1: CR-SPLIT=0.5,
  PARAM_2: ATD-GAIN=7
  PRIORITY: 1

  LINENUM:  2
  SEQUENCE_1: DEFINE
  SEQUENCE_2: F160WL
  TARGNAME: #
  CONFIG: WFPC2
  OPMODE: IMAGE
  APERTURE: #
  SP_ELEMENT: F160BW
  NUM_EXP: 2
  TIME_PER_EXP: 1800s
  PARAM_1: CR-SPLIT=0.5,
  PARAM_2: ATD-GAIN=7
  PRIORITY: 1

  LINENUM:  3		
  SEQUENCE_1: DEFINE
  SEQUENCE_2: F336WL
  TARGNAME: #
  CONFIG: WFPC2
  OPMODE: IMAGE
  APERTURE: #
  SP_ELEMENT: F336W
  NUM_EXP: 1
  TIME_PER_EXP: 600s
  PARAM_1: CR-SPLIT=0.5,
  PARAM_2: ATD-GAIN=15
  PRIORITY: 1

  LINENUM:  4
  SEQUENCE_1: DEFINE
  SEQUENCE_2: F336W
  TARGNAME: #
  CONFIG: WFPC2
  OPMODE: IMAGE
  APERTURE: #
  SP_ELEMENT: F336W
  NUM_EXP: 1
  TIME_PER_EXP: 350s
  PARAM_1: CR-SPLIT=0.0,
  PARAM_2: ATD-GAIN=15
  PRIORITY: 1

  LINENUM: 5
  SEQUENCE_1: USE
  SEQUENCE_2: F160WL
  APERTURE: WFALL-FIX
  TARGNAME: NGC1783
  REQ_1: CYCLE 4 / 5-16;
  REQ_2: PCS MODE F / 5-16;
  REQ_3: GROUP 5-6 NO GAP 

  LINENUM: 6
  SEQUENCE_1: USE
  SEQUENCE_2: F336WL
  APERTURE: WFALL-FIX
  TARGNAME: NGC1783

  LINENUM: 7
  SEQUENCE_1: USE
  SEQUENCE_2: F160W
  APERTURE: PC1-FIX
  TARGNAME: NGC1856
  REQ_1: GROUP 7-8 NO GAP

  LINENUM: 8
  SEQUENCE_1: USE
  SEQUENCE_2: F336W
  APERTURE: PC1-FIX
  TARGNAME: NGC1856
 
  LINENUM: 9
  SEQUENCE_1: USE
  SEQUENCE_2: F160WL
  APERTURE: WFALL-FIX
  TARGNAME: NGC1835
  REQ_1: GROUP 9-10 NO GAP

  LINENUM: 10
  SEQUENCE_1: USE
  SEQUENCE_2: F336WL
  APERTURE: WFALL-FIX
  TARGNAME: NGC1835 
 
  LINENUM: 11
  SEQUENCE_1: USE
  SEQUENCE_2: F160W
  APERTURE: PC1-FIX
  TARGNAME: NGC1978
  REQ_1: GROUP 11-12 NO GAP

  LINENUM: 12
  SEQUENCE_1: USE
  SEQUENCE_2: F336W
  APERTURE: PC1-FIX
  TARGNAME: NGC1978 

  LINENUM: 13
  SEQUENCE_1: USE
  SEQUENCE_2: F160W
  APERTURE: PC1-FIX
  TIME_PER_EXP: x0.79
  TARGNAME: NGC1866
  REQ_1: GROUP 13-14 NO GAP  

  LINENUM: 14
  SEQUENCE_1: USE
  SEQUENCE_2: F336W
  APERTURE: PC1-FIX
  TIME_PER_EXP: x0.52
  TARGNAME: NGC1866 

  LINENUM: 15
  SEQUENCE_1: USE
  SEQUENCE_2: F160W
  APERTURE: PC1-FIX
  TIME_PER_EXP: x0.79
  TARGNAME: NGC2134
  REQ_8: GROUP 15-16 NO GAP

  LINENUM: 16
  SEQUENCE_1: USE
  SEQUENCE_2: F336W
  APERTURE: PC1-FIX
  TIME_PER_EXP: x0.89
  TARGNAME: NGC2134