! $Id: 5415,v 28.1 1995/02/13 13:45:27 pepsa Exp $ coverpage: title_1: THE DISTANCE TO THE M96 GALAXY GROUP: CYCLE4 MEDIUM sci_cat: GALAXIES & CLUSTERS sci_subcat: DISTANCE SCALE proposal_for: GO pi_fname: NIAL pi_mi: R pi_lname: TANVIR pi_inst: 8014 pi_country: UNITED KINGDOM pi_phone: (44)-223-337528 hours_pri: 21.35 num_pri: 2 wf_pc: Y off_fname: DONALD off_lname: LYNDEN-BELL off_title: DIRECTOR off_inst: 8014 off_addr_1: INSTITUTE OF ASTRONOMY off_addr_2: MADINGLEY ROAD off_addr_3: UNIVERSITY OF CAMBRIDGE off_city: CAMBRIDGE off_zip: CB3 OHA off_country: UNITED KINGDOM off_phone: 44-223-337525 ! end of coverpage abstract: line_1: The value of the Hubble constant is one of the key goals of the HST. line_2: Although the current GTO and GO long-term projects address this line_3: issue, they mainly aim to calibrate the infra-red Tully-Fisher line_4: relation on the one hand and the supernova type-1a standard line_5: candles on the other. We argue that the potential problems with line_6: both these approaches make it vital that another independent route line_7: to Ho be pursued in parallel. line_8: We are proposing to do this by calibrating the elliptical/S0 line_9: distance indicators directly in the M96 Group, by obtaining Cepheid line_10: distances to two of the spiral members, NGC3368 and UGC5889. line_11: The M96 group is sufficiently near to be well within the capabilities line_12: of HST to obtain good Cepheid distances, but far enough away that line_13: the discrepancy between the short and long distance scales is already line_14: significant. There is strong evidence that galaxies in the group line_15: are gravitationally bound and at a common distance; determination line_16: of cepheid distances to late-type galaxies in this group will therefore line_17: allow us to calibrate the various elliptical-galaxy distance line_18: indicators that have been measured for their early-type companions. ! ! end of abstract general_form_proposers: lname: TANVIR fname: NIAL mi: R inst: 8014 country: UNITED KINGDOM esa: Y ! lname: FERGUSON fname: HENRY mi: C inst: 3470 country: UNITED STATES esa: N ! lname: ROBINSON fname: DAVID mi: R inst: 8014 country: UNITED KINGDOM esa: Y ! lname: SHANKS fname: THOMAS inst: 8018 country: UNITED KINGDOM esa: Y ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: Our proposal is to search for Cepheids in two galaxies (NGC3368=M96 line_2: and UGC5889). For each galaxy we plan 13 deep (38.2min) exposures line_3: in the V-band (F555W) and 3 (48min) exposures in the I-band (F814W). line_4: The essential requirement is to space the observations so line_5: as to provide good sampling of the light curves of the Cepheids line_6: we expect to see (roughly 8 to 50 day periods). In fact, this program line_7: can be scheduled fairly flexibly since there are a number of ways line_8: in which the observations can be (close to) optimally spaced. line_10: Optimal spacing consists of several observations scheduled with line_11: a range of seperations from 1 to 30 days and then three further line_12: observations seperated by several months. line_13: The I band images will be most useful if taken at the line_14: same time as three of the widely seperated V band images. line_15: Further discussion of the scheduling requirements is line_16: given below. line_18: Although it is not possible to specify SAME ORIENT, line_19: it would be useful, in terms of maximising the line_20: overlapping field of view, to obtain exposures with line_21: similar orientations if that is practical. line_22: SAME ORIENT AND ABSOLUTE ORIENT ADDED BY OPB WITH PI CONSENT. line_23: Please note that we have added an extra epoch and reduced ! question: 3 section: 2 line_1: the V band exposure times fractionally, compared to the phase I line_2: request, whilst keeping the RESOURCE estimate within the same line_3: total space-craft time. This modification was calculated to line_4: be of overall benefit to the program. However, line_5: if this represents a problem to the schedulers, then we line_6: would prefer to revert to the original 12 epochs rather than cutting line_7: the exposure times significantly further. ! question: 4 section: 1 line_1: In order to obtain the high precision photometry necessary to line_2: determine accurate Cepheid distances the high spatial resolution line_3: of the HST is required. Even in exceptional ground based seeing line_4: of 0.5 arcsecs the photometric errors would be greatly increased line_5: particularly due to crowding errors. line_6: Thus, although in principle it may be possible to detect the variability line_7: of the brightest Cepheids from the ground (if the M96 group is at the line_8: lower end of its range) we would not be able to obtain accurate line_9: periods and photometry for an adequate sample of variables. ! question: 5 section: 1 line_1: As explained above, to be useful, the observations must be line_2: spaced to properly sample the light curves of the Cepheids line_3: we find, so as to exclude aliasing and to provide good precision line_4: in estimating the mean magnitudes and the periods. line_6: The fairly rigid timetable given in the EXPOSURE_LOGSHEET below line_7: could probably be modified, in consulation with the proposers, line_8: to accommodate other constraints in scheduling. line_9: In particular, we would be happy to test any timetable suggested line_10: by the schedulers, with our simulation software to line_11: gauge its suitability. ! question: 6 section: 1 line_1: No special calibration exposures. ! ! question: 8 section: 1 line_1: ! question: 9 section: 1 line_1: HCF was PI on the following accepted cycle-2 application, line_2: although that proposal is unrelated to the present one: line_3: GO-3647 THE STAR-FORMING HISTORY OF ELLIPTICAL GALAXIES line_4: HCF was PI on the following accepted cycle-3 application, line_5: although that proposal is unrelated to the present one: line_6: GO-4416 THE HOT STELLAR COMPONENT IN THE CENTERS OF M31 AND M32. line_7: TS is a co-I on the Medium Deep Survey project. ! question: 10 section: 1 line_1: Members of the team have exclusive use of several well specified line_2: graphical workstations which will be adequate to perform the line_3: data-analysis. To aid with this task, large amount of astronomical line_4: software, including IRAF, STSDAS, FIGARO, DAOPHOT-2 is available line_5: as part of the local STARLINK computer service. line_6: NRT and DRTR are both employed as UK HST Support Astronomers and line_7: hence have both the necessary effort and experience to perform line_8: the required data reduction. ! !end of general form text general_form_address: lname: TANVIR fname: NIAL mi: R category: PI inst: 8014 addr_1: Institute of Astronomy addr_2: University of Cambridge addr_3: Madingley Road city: Cambridge zip: CB3 0HA country: UNITED KINGDOM phone: (44)-223-337528 telex: nrt@mail.ast.cam.ac.uk ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: NGC3368 name_2: M96 descr_1: E,301, descr_2: B,147 pos_1: RA = 10H 46M 44S +/- 0.01S, pos_2: DEC = +11D 51' 40" +/- 0.1", equinox: J2000 comment_1: THESE FLUX VALUES ARE TYPICAL FOR comment_2: ONE OF OUR EXPECTED CEPHEIDS. comment_3: THE +/- ENTERED HERE REFER TO comment_4: RANGES RATHER THAN UNCERTAINTIES. fluxnum_1: 1 fluxval_1: V=25 +/- 1.5 fluxnum_2: 1 fluxval_2: V-I=0.8 +/- 0.3 fluxnum_3: 1 fluxval_3: E(B-V)=0.05 +/- 0.05 ! targnum: 2 name_1: UGC5889 name_2: DDO88 descr_1: E,301, descr_2: B,147 pos_1: RA = 10H 47M 21S +/- 0.01S, pos_2: DEC = +14D 04' 15" +/- 0.1", equinox: J2000 comment_1: SAME COMMENTS AS ABOVE. fluxnum_1: 1 fluxval_1: V=25 +/- 1.5 fluxnum_2: 1 fluxval_2: V-I=0.8 +/- 0.3 fluxnum_3: 1 fluxval_3: E(B-V)=0.05 +/- 0.05 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 101.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.6 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; AT 31-MAR-94 +/- 20D; req_2: ORIENT 112D +/- 2D comment_1: CLEARLY S/N GIVEN HERE IS APPROX comment_2: GIVEN THAT WE EXPECT TO FIND comment_3: CEPHEIDS OVER A RANGE OF MAGS. comment_4: SEE QNS 3 AND 5 OF GENERAL FORM comment_5: FOR DESCRIPTION OF OUR OVERALL comment_6: SCHEDULING REQUIREMENTS. ! linenum: 101.500 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F814W num_exp: 1 time_per_exp: 3000S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.4 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; req_2: GROUP 101.0-101.5 NO GAP; req_3: SAME ORIENT FOR 101.5-110.5 AS 101 ! linenum: 102.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 101.0 BY 35H +/- 3H ! linenum: 103.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 101.0 BY 3.5D +/- 5H ! linenum: 104.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 101.0 BY 6.5D +/- 8H ! linenum: 105.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 101.0 BY 11D +/- 12H ! linenum: 106.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 101.0 BY 17D +/- 16H ! linenum: 107.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 101.0 BY 27D +/- 20H ! linenum: 108.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 101.0 BY 40D +/- 1D ! linenum: 109.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 101.0 BY 60D +/- 2D ! linenum: 110.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.6 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; AFTER 101.0 BY 88D +/- 3D ! linenum: 110.500 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F814W num_exp: 1 time_per_exp: 3000S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.4 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; GROUP 110.0-110.5 NO GAP ! linenum: 111.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 101.0 BY 200D +/- 20D; req_2: ORIENT 180D +/- 1D FROM 101 ! linenum: 112.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.6 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; AFTER 111.0 BY 5D +/- 1D; req_2: ORIENT 188D +/- 1D FROM 101.0/112.0-112.5 comment_1: ROLL AS CLOSE TO 300D (U3) comment_2: AS POSSIBLE. ! linenum: 112.500 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F814W num_exp: 1 time_per_exp: 3000S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.4 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; req_2: GROUP 112.0-112.5 NO GAP comment_1: ROLL AS CLOSE TO 300D (U3) comment_2: AS POSSIBLE. ! linenum: 113.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 111.0 BY 13D +/- 1D; req_2: ORIENT 188D +/- 1D FROM 101.0; req_3: POS TARG 25, 0 comment_1: ROLL AS CLOSE TO 300D (U3) comment_2: AS POSSIBLE. ! linenum: 201.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.6 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; AT 31-MAR-94 +/- 20D; req_2: ORIENT 112D +/- 2D ! linenum: 201.500 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F814W num_exp: 1 time_per_exp: 3000S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.4 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; req_2: GROUP 201.0-201.5 NO GAP; req_3: SAME ORIENT FOR 201.5 - 209 AS 201 ! linenum: 202.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 201.0 BY 35H +/- 3H ! linenum: 203.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 201.0 BY 3.5D +/- 5H ! linenum: 204.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 201.0 BY 6.5D +/- 8H ! linenum: 205.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 201.0 BY 11D +/- 12H ! linenum: 206.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 201.0 BY 17D +/- 16H ! linenum: 207.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 201.0 BY 27D +/- 20H ! linenum: 208.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 201.0 BY 40D +/- 1D ! linenum: 209.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 201.0 BY 60D +/- 2D ! linenum: 210.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.6 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; AFTER 201.0 BY 265D +/- 20D; req_2: POS TARG 11, -15 ! linenum: 210.500 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F814W num_exp: 1 time_per_exp: 3000S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.4 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; req_2: GROUP 210.0-210.5 NO GAP; req_3: SAME POS FOR 210.5 AS 210.0 ! linenum: 211.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 210.0 BY 5D +/- 1D; req_2: ORIENT 180D +/- 1D FROM 201/ req_3: 210.0 - 211.0, 213.0; req_4: POS TARG 11, -15 ! linenum: 212.000 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.6 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; AT 6-APR-1995 +/- 10D; req_2: ORIENT 112D +/- 0D; req_3: POS TARG -8, -8 ! linenum: 212.500 targname: NGC3368 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F814W num_exp: 1 time_per_exp: 3000S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.4 param_2: CR-TOLERANCE=0.0 req_1: CYCLE 4; req_2: GROUP 212.0-212.5 NO GAP; req_3: SAME POS FOR 212.5 AS 212.0 ! linenum: 213.000 targname: UGC5889 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F555W num_exp: 1 time_per_exp: 2400S s_to_n: 10 fluxnum_1: 1 priority: 1 param_1: CR-SPLIT=0.5 param_2: CR-TOLERANCE=0.15 req_1: CYCLE 4; AFTER 210.0 BY 22D +/- 1D; req_2: POS TARG 11, -15; req_3: SAME ORIENT FOR 213 AS 210 ! ! ! end of exposure logsheet ! No scan data records found