! File: 4084C.PROP ! Database: PEPDB ! Date: 20-FEB-1994:07:59:44 coverpage: title_1: GLOBULAR CLUSTER CORES, WFPC GTO AUGMENTATION, title_2: CYCLE 2 sci_cat: STELLAR POPULATIONS proposal_for: AUG/WFC cont_id: 3640 pi_title: PROF. pi_fname: JAMES pi_mi: A. pi_lname: WESTPHAL pi_inst: CALTECH pi_country: USA pi_phone: (818) 356-4900 keywords_1: GLOBULAR CLUSTERS hours_pri: 14.64 num_pri: 5 pi_position: PROF. PLANETARY SCI. ! end of coverpage abstract: line_1: Stellar Populations Part III: Globular Cluster Cores. The cores line_2: of 4 globular clusters will be imaged in U to study core properties line_3: and search for collapsed cusps. The clusters are relatively nearby line_4: and span the range from very regular to very cusplike. ! ! end of abstract general_form_proposers: lname: WESTPHAL fname: JAMES mi: A. inst: CALTECH country: USA ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: All observations of the four globular clusters will consist of line_2: F336W exposures, each split into two equal-length exposures to line_3: facilitate the removal of cosmic rays. line_5: For each of the four clusters, three 2200 second C-R split observa- line_6: tions will be taken at each of two slightly different pointings. line_7: The slightly different pointings will provide the data necessary to line_8: compensate for anticipated calibration problems with the data. line_9: For three of the four clusters (all except M15), one 800 second C-R line_10: split observation will be taken to safeguard against the possibility line_11: of an unusually bright star saturating the Planetary Camera. line_12: For each cluster, all useful data will be combined to improve the line_13: signal-to-noise ratio of the data. ! question: 4 section: 1 line_1: Many groundbased observations of galactic globular cluster cores line_2: have been taken during the past few decades. Atmospheric seeing has line_3: limited the resolution of the detailed nature of these cluster cores. line_4: By being outside the bulk of the Earth's atmosphere, the HST can line_5: produce observations that have finer resolution than is routinely line_6: obtainable at groundbased observatories. The scientific yield of line_7: this finer resolution has been demonstrated by the analysis of the line_8: SAO observations of the center of the glactic globular cluster M15 line_9: (see section 8a, 8b, and 8c of this proposal). ! question: 7 section: 1 line_1: The following analysis will be performed individual image, after line_2: having removed the cosmic rays indicated by comparison of all images. line_3: This analysis will also be performed on the registered and line_4: summed image. line_6: 1) Construct an observationally determined point-spread-function (PSF) line_7: from isolated stars in the field. 2) Locate the bright resolved line_8: stars near the cluster center, map their locations, determine their line_9: distribution, fit a scaled PSF model to them and remove them from line_10: the image. 3) Use the PSF to deconvolve the difference image (i.e. line_11: with the bright stars near the center removed) and fit a power-law line_12: model to the core. 4) Use the result of the above fit as a starting line_13: point for iteratively fitting a convolved power-law model to the line_14: original (i.e. not deconvolved) residual core image. 5) Determine line_15: the center of the cluster in terms of the center of the bright line_16: resolved star component, the residual core component, and the total line_17: light distribution. 6) Note the morphology and coincidence of the line_18: above centers. 7) Compare WFPC data with groundbased data. line_19: Finally, look for comparable trends between clusters. ! question: 8 section: 1 line_1: All of the 2200s exposures given in the GC800 and GC2000 line_2: sequences may be adjusted by +/- 20 percent in order to line_3: fit within one orbit. However, the CR-split level must line_4: remain equal when adjusting times as needed. ! !end of general form text general_form_address: lname: O'NEIL fname: EARL mi: J. category: CON inst: NOAO/KPNO addr_1: 950 N. CHERRY addr_2: P.O. BOX 26732 city: TUCSON state: AZ zip: 85726 country: USA phone: (602) 327-5511 ! lname: WESTPHAL fname: JAMES mi: A. title: PROF. category: PI inst: CALTECH addr_1: M/S 170-25 addr_2: DIVISION OF GEOLOGICAL addr_3: & PLANETARY SCIENCES city: PASADENA state: CA zip: 91125 country: USA phone: (818) 356-4900 ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: NGC5272-M3 descr_1: C, 201 pos_1: RA= 13H39M52.9S +/-0.1S, pos_2: DEC= +28D37'38" +/-1" equinox: 1950.0 fluxnum_1: 1 fluxval_1: SURF(V)=16.3 ! targnum: 2 name_1: NGC5272-OFF descr_1: C, 201 pos_1: RA= 13H39M52.9S +/-0.1S, pos_2: DEC= +28D37'28" +/-1" equinox: 1950.0 fluxnum_1: 1 fluxval_1: SURF(V)=16.3 ! targnum: 3 name_1: NGC6752 descr_1: C, 201 pos_1: RA= 19H06M27.3S +/-0.1S, pos_2: DEC= -60D03'50" +/-1" equinox: 1950.0 comment_1: B-V=0.68 ALSO FOR FLUX DATA fluxnum_1: 1 fluxval_1: SURF(V) = 16.2 ! targnum: 4 name_1: NGC6752-OFF descr_1: C, 201 pos_1: RA= 19H06M27.3S +/-0.1S, pos_2: DEC= -60D03'40" +/-1" equinox: 1950.0 comment_1: B-V=0.68 ALSO FOR FLUX DATA fluxnum_1: 1 fluxval_1: SURF(V) = 16.2 ! targnum: 9 name_1: BD+75D325 descr_1: J, 704 pos_1: RA = 08H 10M 49.31S +/- 1S, pos_2: DEC = +74D 57' 57.5" +/- 1", equinox: 2000 comment_1: UV STANDARD; SP.TYPE = O5P; comment_2: FOR USE WITH NGC 5272 OBS fluxnum_1: 1 fluxval_1: V = 9.54 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 1.000 sequence_1: DEFINE sequence_2: GC800 targname: # config: PC opmode: IMAGE aperture: PC6 sp_element: F336W num_exp: 1 time_per_exp: 800S priority: # param_1: CR-SPLIT=0.5, param_2: CR-TOLERANCE=0.0, param_3: PRE-FLASH=YES req_1: NON-INT / 1-2; req_2: GROUP 1-2 WITHIN 1D; req_3: PCS MODE C / 1-2 comment_1: GTO AUGMENTATION, CYCLE 2 comment_2: EJO/RML 3/18/92 ! linenum: 2.000 sequence_1: ^ targname: # config: PC opmode: IMAGE aperture: PC6 sp_element: F336W num_exp: 3 time_per_exp: 2000S priority: # param_1: CR-SPLIT=0.5, param_2: CR-TOLERANCE=0.0, param_3: PRE-FLASH=YES req_1: SAME POS FOR 2 AS 1; req_2: SAME ORIENT FOR 2 AS 1 comment_1: EACH OF 3 EXP INTENDED TO FIT WITHIN comment_2: ONE ORBIT. MODIFY THE 2200S EXP TIME comment_3: +/- 20 PERCENT TO ACCOMPLISH THIS, comment_4: BUT RESPECT THE EQUAL CR SPLIT. ! linenum: 5.000 sequence_1: DEFINE sequence_2: GC2200 targname: # config: PC opmode: IMAGE aperture: PC6 sp_element: F336W num_exp: 1 time_per_exp: 2000S priority: # param_1: CR-SPLIT=0.5, param_2: CR-TOLERANCE=0.0, param_3: PRE-FLASH=YES req_1: NON-INT; req_2: PCS MODE C comment_1: THIS EXPOSURE INTENDED TO FIT WITHIN comment_2: ONE ORBIT. MODIFY THE 2200S EXP TIME comment_3: +/- 20 PERCENT TO ACCOMPLISH THIS, comment_4: BUT RESPECT THE EQUAL CR SPLIT. ! linenum: 8.000 sequence_1: USE sequence_2: GC800 targname: NGC5272-M3 priority: 1 req_1: GROUP 8-10 WITHIN 3D; req_2: CYCLE 2 / 8-12 ! linenum: 8.500 sequence_1: USE sequence_2: GC2200 targname: NGC5272-M3 priority: 1 req_1: SAME ORIENT FOR 8.5-9 AS 8 ! linenum: 9.000 sequence_1: USE sequence_2: GC800 targname: NGC5272-OFF priority: 1 ! linenum: 10.000 targname: BD+75D325 config: PC opmode: IMAGE aperture: PC6 sp_element: F336W num_exp: 2 time_per_exp: 4S priority: 1 param_1: CR-SPLIT=NO, param_2: PRE-FLASH=YES req_1: PCS MODE C comment_1: PSF STAR FOR M3 OBSERVATION; comment_2: TO BE GROUPED WITH CLUSTER OBS ! linenum: 11.000 sequence_1: USE sequence_2: GC800 targname: NGC6752 priority: 1 req_1: GROUP 11-12 WITHIN 1D ! linenum: 11.500 sequence_1: USE sequence_2: GC2200 targname: NGC6752 priority: 1 req_1: SAME ORIENT FOR 11.5-12 AS 11 ! linenum: 12.000 sequence_1: USE sequence_2: GC800 targname: NGC6752-OFF priority: 1 ! ! end of exposure logsheet ! No scan data records found