! $Id: 5384,v 6.1 1994/07/27 17:21:58 pepsa Exp $ coverpage: title_1: RESOLVED AND COMPOSITE PROPERTIES OF THE GIANT HII REGIONS IN M33 title_2: CYCLE4MEDIUM sci_cat: HOT STARS sci_subcat: CLUSTERS proposal_for: GO pi_fname: WILLIAM pi_lname: WALLER pi_inst: HUGHES STX pi_country: USA pi_phone: (301)513-5475 keywords_1: GALAXY;M33 keywords_2: CLUSTERS;OB ASSOCIATIONS hours_pri: 2.23 num_pri: 6 wf_pc: Y funds_amount: 77416 funds_length: 12 funds_date: JUN-94 pi_position: SENIOR SCIENTIST off_fname: DAVID off_lname: SHERRY off_title: CONTRACTS DIRECTOR off_inst: 3480 off_addr_1: 4400 FORBES BLVD. off_city: LANHAM off_state: MD off_zip: 20706 off_country: USA off_phone: (301)-794-5306 ! end of coverpage abstract: line_1: We propose to evaluate the degree to which metal abundance affects line_2: stellar population at the high-mass end. We will target the galaxy line_3: M33, whose proximity and large sample of HII regions of differing line_4: metallicity make it ideally suited for such a study. Rather than line_5: relying on COMPOSITE spectral indices of stellar population, we will line_6: exploit the superior acuity of the HST to RESOLVE the individual stars line_7: that underly and power 6 of the brightest HII regions in M33. Through line_8: multi-band imaging with the WFPC2 camera and subsequent photometry, line_9: we will be able to differentiate among the upper main-sequence, giant, line_10: supergiant, and Wolf-Rayet stars. Once we resolve and line_11: decompose the ionizing clusters, we will then be able to provide a line_12: critical evaluation of the relationship between metallicity and stellar line_13: population. Moreover, by comparing the resolved stellar populations line_14: in M33's giant HII regions with their composite colors and line_15: emission-line properties, we will be able to provide an essential line_16: foundation for interpreting the composite spectral indices of starburst line_17: regions in more distant galaxies. ! ! end of abstract general_form_proposers: lname: WALLER fname: WILLIAM inst: 3480 country: USA ! lname: DRISSEN fname: LAURENT inst: 3470 country: USA ! lname: HEAP fname: SARA inst: 2866 country: USA ! lname: HODGE fname: PAUL inst: 3760 country: USA ! lname: MALUMUTH fname: ELIOT inst: 1780 country: USA ! lname: PARKER fname: JOEL inst: 2866 country: USA ! lname: TAYLOR fname: DAVID inst: 1780 country: USA ! lname: WILSON fname: CHRISTINE inst: 4642 country: CANADA ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: To resolve and characterize the brightest and hottest stars in M33's giant line_2: HII regions, we propose to use the WFPC2 to obtain PC images of 6 HII regions line_3: through filters that approximate the Johnson UBV passbands. The filters used line_4: will be the F336W (U), F439W (B), and F547M (V), the later of which avoids the line_5: strong [OIII] and H-beta emission lines. To maximize the prominence of the line_6: hottest stars in the crowded fields and to provide further constraints on the line_7: reddening and spectral types of the stars, we will also obtain frames through line_8: the F170W ultraviolet filter. The 6 targets are giant HII regions which span line_9: a wide range of metallicities and environments --- from the near-nuclear HII line_10: region CC 93 (O/H x 10e4 = 10.5) to the outer-disk HII region NGC 588 line_11: (O/H x 10e4 = 2.0). line_13: All exposure times are based on our desire to achieve photometric accuracies line_14: of 10 percent or better down to V=21.1 magnitude. This can be done, if we line_15: obtain a S/N ratio of about 30 in the central pixel of each resolved star. line_16: To obtain this S/N ratio will require exposures of 360S, 320S, 360S, and 200S line_17: respectively for the F170W, F336W, F439W, and F547M filters. Each exposure line_18: will be split into two equal exposures using the CR-SPLIT=0.5 optional line_19: parameter to facilitate the removal of cosmic-ray events. Since the HII line_20: regions are extended sources, they will be centered in the PC1 field of view line_21: by using the PC1-FIX aperture. These exposures will allow us to achieve line_22: a photometric accuracy of 0.10 mag or better for any main sequence star line_23: earlier than B0, and yet avoid saturation of the brighter O-type supergiants. ! question: 3 section: 2 line_1: In addition, a narrow-band image of NGC 588 will be obtained line_2: through filter F469N with the intention of identifying Wolf-Rayet stars through line_3: their HeII (4686A) line emission. A 600S CR-SPLIT=0.5 exposure line_4: will achieve a S/N similar to those obtained by Drissen et al. (1993) line_5: in their WF/PC-1 imaging of NGC 595 and NGC 604. The narrow-band imaging of line_6: NGC 588 is motivated by spectroscopic evidence for HeII emission line_7: from W-R stars in this HII regions (Conti and Massey 1981). NGC 588 is of line_8: special interest because of its exceptionally low metallicity. ! question: 4 section: 1 line_1: Ground-based resolution of ionizing clusters into individual stars has been line_2: achieved with limited success for some galaxies of the Local Group (cf. Massey line_3: et al. 1989). HST observations during Cycles 1-3 have provided much clearer line_4: views of such objects as 30 Doradus in the LMC, NGC 346 in the SMC, and NGC 604 line_5: in M33. At the distance of M33, the superior acuity of the HST enabled Drissen line_6: et al. (1993) to resolve a multitude of hot luminous stars -- even line_7: in the most crowded cores of the HII regions. To classify these stars and line_8: the stellar populations in M33's other giant HII regions, it is necessary to line_9: conduct U,B,V, abd UV imaging using the HST. The additional narrow band line_10: imaging at 4690 A will enable us to isolate the extremely hot WR-type stars. line_11: By targeting 6 HII regions of differing metallicity, we will be able to line_12: characterize their ionizing stellar populations and evaluate their sensitivity line_13: to metallicity -- all in the same galaxy. This cannot be done via ground-based line_14: imaging, nor can it be done with any of the prior or currently scheduled HST line_15: programs. ! question: 5 section: 1 line_1: For each of the 6 targets, all of the exposures of that target line_2: must be taken at the same pointing and roll-angle. This is achieved line_3: through the use of the SEQ NO GAP special requirement. ! question: 6 section: 1 line_1: Provided that flat field exposures are obtained through the F170W, F336W, line_2: F439W, F547M, and F469N filters as part of the regular calibration line_3: plan, no special calibration exposures are required for this program. ! ! question: 8 section: 1 line_1: ! question: 9 section: 1 line_1: See phase 1 proposal. ! question: 10 section: 1 line_1: See phase 1 proposal. ! !end of general form text general_form_address: lname: WALLER fname: WILLIAM category: PI inst: 3480 addr_1: Code 681 addr_2: Goddard Space Flight Center city: Greenbelt state: MD zip: 20771 country: USA phone: (301) 513-5475 telex: WALLER@STARS.GSFC.NASA.GOV ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: M33-NEB1 name_2: CC93 descr_1: D, descr_2: 203 pos_1: RA = 01H 33M 52.51S +/- 0.15S, pos_2: DEC = +30D 39' 17.4" +/- 2.0" equinox: J2000 rv_or_z: V=-180 fluxnum_1: 1 fluxval_1: V=20.6 fluxnum_2: 1 fluxval_2: B-V=-0.3 fluxnum_3: 2 fluxval_3: E(B-V)=0.16 ! targnum: 2 name_1: M33-NEB2 name_2: IC142 descr_1: D, descr_2: 203 pos_1: RA = 01H 33M 55.70S +/- 0.15S, pos_2: DEC = +30D 45' 26.0" +/- 2.0" equinox: J2000 rv_or_z: V=-180 fluxnum_1: 1 fluxval_1: V=20.6 fluxnum_2: 1 fluxval_2: B-V=-0.3 fluxnum_3: 2 fluxval_3: E(B-V)=0.16 ! targnum: 3 name_1: M33-NEB3 name_2: MA2 descr_1: D, descr_2: 203 pos_1: RA = 01H 34M 15.39S +/- 0.15S, pos_2: DEC = +30D 37' 07.0" +/- 2.0" equinox: J2000 rv_or_z: V=-180 fluxnum_1: 1 fluxval_1: V=20.6 fluxnum_2: 1 fluxval_2: B-V=-0.3 fluxnum_3: 2 fluxval_3: E(B-V)=0.16 ! targnum: 4 name_1: M33-NEB4 name_2: NGC588 descr_1: D, descr_2: 203 pos_1: RA = 01H 32M 45.56S +/- 0.15S, pos_2: DEC = +30D 38' 57.6" +/- 2.0" equinox: J2000 rv_or_z: V=-180 fluxnum_1: 1 fluxval_1: V=20.6 fluxnum_2: 1 fluxval_2: B-V=-0.3 fluxnum_3: 2 fluxval_3: E(B-V)=0.16 ! targnum: 6 name_1: M33-NEB6 name_2: NGC595 descr_1: D, descr_2: 203 pos_1: RA = 01H 33M 33.61S +/- 0.15S, pos_2: DEC = +30D 41' 32.0" +/- 2.0" equinox: J2000 rv_or_z: V=-180 fluxnum_1: 1 fluxval_1: V=20.6 fluxnum_2: 1 fluxval_2: B-V=-0.3 fluxnum_3: 2 fluxval_3: E(B-V)=0.16 ! targnum: 7 name_1: M33-NEB7 name_2: NGC604 descr_1: D, descr_2: 203 pos_1: RA = 01H 34M 32.85S +/- 0.15S, pos_2: DEC = +30D 47' 01.6" +/- 2.0" equinox: J2000 rv_or_z: V=-180 fluxnum_1: 1 fluxval_1: V=20.6 fluxnum_2: 1 fluxval_2: B-V=-0.3 fluxnum_3: 2 fluxval_3: E(B-V)=0.16 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 1.100 targname: M33-NEB1 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F170W num_exp: 1 time_per_exp: 700S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; req_2: SEQ 1.1-1.4 NO GAP ! linenum: 1.200 targname: M33-NEB1 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F336W num_exp: 1 time_per_exp: 320S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 1.300 targname: M33-NEB1 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F439W num_exp: 1 time_per_exp: 360S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 1.400 targname: M33-NEB1 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F547M num_exp: 1 time_per_exp: 200S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 2.100 targname: M33-NEB2 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F170W num_exp: 1 time_per_exp: 700S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; req_2: SEQ 2.1-2.4 NO GAP ! linenum: 2.200 targname: M33-NEB2 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F336W num_exp: 1 time_per_exp: 320S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 2.300 targname: M33-NEB2 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F439W num_exp: 1 time_per_exp: 360S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 2.400 targname: M33-NEB2 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F547M num_exp: 1 time_per_exp: 200S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 3.100 targname: M33-NEB3 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F170W num_exp: 1 time_per_exp: 700S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; req_2: SEQ 3.1-3.4 NO GAP ! linenum: 3.200 targname: M33-NEB3 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F336W num_exp: 1 time_per_exp: 320S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 3.300 targname: M33-NEB3 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F439W num_exp: 1 time_per_exp: 360S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 3.400 targname: M33-NEB3 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F547M num_exp: 1 time_per_exp: 200S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 4.100 targname: M33-NEB4 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F170W num_exp: 1 time_per_exp: 700S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; req_2: SEQ 4.1-4.5 NO GAP ! linenum: 4.200 targname: M33-NEB4 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F336W num_exp: 1 time_per_exp: 320S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 4.300 targname: M33-NEB4 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F439W num_exp: 1 time_per_exp: 360S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 4.400 targname: M33-NEB4 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F547M num_exp: 1 time_per_exp: 200S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 4.500 targname: M33-NEB4 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F469N num_exp: 1 time_per_exp: 600S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 6.100 targname: M33-NEB6 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F170W num_exp: 1 time_per_exp: 700S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; req_2: SEQ 6.1-6.4 NO GAP ! linenum: 6.200 targname: M33-NEB6 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F336W num_exp: 1 time_per_exp: 320S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 6.300 targname: M33-NEB6 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F439W num_exp: 1 time_per_exp: 360S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 6.400 targname: M33-NEB6 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F547M num_exp: 1 time_per_exp: 200S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! linenum: 7.100 targname: M33-NEB7 config: WFPC2 opmode: IMAGE aperture: PC1-FIX sp_element: F170W num_exp: 1 time_per_exp: 700S s_to_n: 30 fluxnum_1: 1 fluxnum_2: 2 priority: 1 param_1: CR-SPLIT = 0.5 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; ! ! end of exposure logsheet ! No scan data records found