! $Id: 5410,v 4.1 1994/07/27 17:38:41 pepsa Exp $ coverpage: title_1: SHOCK MORPHOLOGY IN STAR-FORMING RING GALAXIES title_2: - CYCLE 4 MEDIUM sci_cat: GALAXIES & CLUSTERS sci_subcat: PECULIAR/INTERACTING proposal_for: GO pi_fname: KIRK pi_mi: D. pi_lname: BORNE pi_inst: STSCI pi_country: USA pi_phone: 410-338-4945 hours_pri: 4.94 num_pri: 2 wf_pc: Y off_fname: HERVEY off_lname: STOCKMAN off_title: ASSISTANT DIRECTOR off_inst: STSCI off_addr_1: 3700 SAN MARTIN DRIVE off_addr_2: HOMEWOOD CAMPUS off_city: BALTIMORE off_state: MD off_zip: 21218 off_country: USA off_phone: 410-338-4730 ! end of coverpage abstract: line_1: We propose to obtain multi-band WFPC2 images of two smoke-ring line_2: galaxies chosen on the basis of showing evidence (in ground-based line_3: images) for strong star formation in the ring. We wish to map the sharp line_4: features in those rings (e.g., density waves, shock fronts, HII regions, line_5: star-forming complexes). We will use the images to study various line_6: phenomena: (1) the thresholds for star formation in the ring; (2) the line_7: size distribution of the HII regions (compared to that in normal line_8: galaxies); (3) evidence for a two-phase starburst (as in Eta Carinae); line_9: (4) evidence for color gradients across the ring; (5) comparisons line_10: between the age of the tidally induced starburst and the dynamical age line_11: of the collision event; (6) the gas dynamical response to strong line_12: galactic scale perturbations (density waves); and (7) the character of line_13: small-scale structure observed in the rings in terms of starburst line_14: strength, density wave strength, magnitude of gas compression, scale line_15: length of shocks, location of star-forming regions, and collision age. line_16: We will test the results against sophisticated stars+gas simulations of line_17: collision-induced ring morphologies. This will be a significant test line_18: since the smoke-ring galaxies represent a class of colliding galaxies line_19: with very simple and easily interpreted histories: a one-time passage line_20: of a companion nearly through the center of a gas-rich disk galaxy. ! ! end of abstract general_form_proposers: lname: BORNE fname: KIRK mi: D. inst: STSCI country: USA ! lname: APPLETON fname: PHILIP inst: IOWA STATE UNIVERSITY country: USA ! lname: LUCAS fname: RAY mi: A. inst: STSCI country: USA ! lname: SCHULTZ fname: ALFRED inst: STSCI country: USA ! lname: SPIGHT fname: LON inst: UNIVERSITY OF NEVADA country: USA ! lname: STRUCK-MARCELL fname: CURTIS inst: IOWA STATE UNIVERSITY country: USA ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: We plan to image two ring galaxies, AM0035-335 ("The Cartwheel") and IIZw28, line_2: using the WFPC2. Number of exposures and time_per_exposure, etc. are as follows: line_4: AM0035-335 line_5: F450W 2x800s CR-SPLIT=NO WFALL-FIX POS TARG +10,-22 line_6: F450W 2x800s CR-SPLIT=NO WFALL-FIX POS TARG +12,-21 line_7: F814W 1x400s + 1x500s CR-SPLIT=NO WFALL-FIX POS TARG +10,-22 line_8: F814W 1x500s + 1x400s CR-SPLIT=NO WFALL-FIX POS TARG +12,-21 line_10: IIZw28 line_11: F450W 2x800s CR-SPLIT=NO WF3 DEFAULT POSITION line_12: F450W 2x800s CR-SPLIT=NO WF3 POS TARG +1,+2 line_13: F814W 1x400s + 1x500s CR-SPLIT=NO WF3 DEFAULT POSITION line_14: F814W 1x500s + 1x400s CR-SPLIT=NO WF3 POS TARG +1,+2 line_15: F673N 4x1000s CR-SPLIT=NO WF3 DEFAULT POSITION line_16: F673N 2x1000s + 2x900s CR-SPLIT=NO WF3 POS TARG +1,+2 line_18: The F814W exposures of both galaxies have been split into two parts of unequal line_19: length to help in fitting them into an orbit. We do not believe that this line_20: difference of 100s between the F814W 400s frames and the F814W 500s frames will line_21: be very significant in terms of S/N when comparing them for cosmic ray removal. line_22: The final F673N exposures were split into 2x1000 and 2x900 parts so as to meet line_23: TAC time allocation -- 1000s vs 900s should be insignificant in final analysis. ! question: 3 section: 2 line_1: Other details are as follows: line_3: AM0035-335 line_4: A specific ORIENT angle is requested in order to properly place the target and line_5: two nearby galaxies in the three Wide Field chips' L-shaped field of view. line_6: Because the natural orientation on the sky of this galaxy and its two other line_7: companions is also somewhat L-shaped, there is one preferred ORIENT angle of line_8: 338D +/-15D when used in combination with the WFALL-FIX aperture and a POS line_9: TARG position of +10,-22. The target position chosen is an area between the line_10: central condensation and the outer ring of AM0035-335, and we place this point line_11: on the WF3-WF4 chip boundary about 32 arcsec away from the apex of the pyramid line_12: in the Y-direction. ( The default WFALL-FIX position is on WF3 at 10" in X and line_13: 10" in Y from the apex of the pyramid, hence our use of POS TARG +10,-22. ) A line_14: small offset from this position ( 2" in X and 1" in Y, to +12,-21 ) is used to line_15: assist in detecting effects of bad pixels, etc. The off-center central knot in line_16: AM0035-335 will be placed on WF3, and the elongated outer ring of the galaxy line_17: will be stretched across both WF3 and WF4, while the two nearby small galaxies line_18: will be on WF2. The +/-15D range allows the two small galaxies to be displaced line_19: across WF2, from one side of the chip to the other, but still keeps them in line_20: its field of view. All exposures of this galaxy should be done GROUP NO GAP line_21: and should be taken at the SAME ORIENT. ! question: 3 section: 3 line_1: IIZw28 line_2: The optimal WF3 aperture location is our choice for this galaxy which is much line_3: smaller in angular size than AM0035-335. We have again requested GROUP NO GAP line_4: for all exposures of this target, and all images should again also be taken at line_5: the SAME ORIENT. Also, as with AM0035-335, we have specified small POS TARG line_6: offsets to assist us in detecting the effects of bad pixels, etc. There is no line_7: special preferred ORIENT for this target due to its geometry and small size. line_8: Any ORIENT angle will do, as long as the data are all taken at the SAME ORIENT ! question: 4 section: 1 line_1: HST provides the unique opportunity to perform high-resolution imaging of the line_2: point-like and sharp-edged features produced in these galaxies as a result of line_3: their clean head-on collision with a companion (eg, shock fronts, HII regions, line_4: sharp color gradients). These galaxies provide an ideal laboratory for studying line_5: the gas dynamical response in strongly penetrating galaxy collisions and for line_6: studying in particular: the properties (eg, amplitudes, locations, phase lags) line_7: of the propagating wavefronts of star formation and shocked compressed gas, the line_8: size and spatial distribution of star-forming regions and HII complexes, and line_9: the potential production of globular clusters in the wake of the expanding line_10: ring. Since most of these features in the galaxies are not resolvable from the line_11: ground, HST imaging is required. In particular, all of the most-structured line_12: ring galaxies are at redshifts that place them just beyond the resolution limit line_13: of ground-based facilities, with the thickness of the rings being only a few line_14: arcseconds across. line_16: Ground-based BVRI photometry and IUE UV spectra of ring galaxies (eg, Arp 147; line_17: Schultz et al 1991) reveal evidence of a young stellar population in the ring. line_18: From the colors, different knots in the rings actually appear to have different line_19: stellar population ages. There also appears to be a sudden transition at the line_20: ring boundary from older to younger stars. Parameterizing the onset of this line_21: transition, its radial steepness, and its azimuthal variations, and mapping the line_22: fine-scale spatial variations in stellar population mixes are among the goals line_23: and unique by-products of our proposed HST observations. ! question: 5 section: 1 line_1: As described in Question #3, we request a special orientation for one of our line_2: targets: AM0035-335. This is requested because of the natual L-shaped line_3: distribution of the various components in this small group of galaxies. This line_4: L-shape arrangement matches the L-arrangement of the 3 WF chips in only one line_5: orientation: ORIENT = 338D +/- 15D. The specified range in the orientation line_6: still permits all of the different target objects to appear fully on the line_7: 3 WF chips. Going beyond this range would cause one or the other of the two line_8: small companion galaxies to fall off the WF2 boundary and it would cause line_9: significant portions of the ring in the primary target (a ring galaxy) to line_10: fall off the WF3 and WF4 boundaries. This galaxy has an elliptical-ring line_11: morphology, with dimensions 74 arcsec by 60 arcsec. The long axis of the line_12: ellipse will straddle chips WF3 and WF4, thus splitting the object across line_13: two chips. Any deviation from the stated range of orientations will cause line_14: parts of the ring to enter the PC1 chip and other parts of the ring to be line_15: totally unobserved. This would not be acceptable. ! question: 6 section: 1 line_1: (none) ! ! question: 8 section: 1 line_1: (none) ! question: 9 section: 1 line_1: (none) ! question: 10 section: 1 line_1: STScI Investigators: line_2: Some research assistance will be provided to the PI as a regular "visiting" GO line_3: for a brief period after the data are obtained. line_4: Workstations and numerous data analysis packages are available on site, with line_5: expert assistance also available. line_7: Iowa State Investigators: line_8: Workstations and numerous data analysis packages are also available on site. ! !end of general form text general_form_address: lname: BORNE fname: KIRK mi: D. category: PI inst: STSCI addr_1: 3700 SAN MARTIN DRIVE addr_2: HOMEWOOD CAMPUS city: BALTIMORE state: MD zip: 21218 country: USA phone: 410-338-4945 telex: BORNE@STSCI.EDU ! lname: BORNE fname: KIRK mi: D. category: CON inst: STSCI addr_1: 3700 SAN MARTIN DRIVE addr_2: HOMEWOOD CAMPUS city: BALTIMORE state: MD zip: 21218 country: USA phone: 410-338-4945 telex: BORNE@STSCI.EDU ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: AM0035-335 descr_1: E,301,320 pos_1: RA = 00H 37M 39.55S +/- 0.1S, pos_2: DEC = -33D 42' 48.3" +/- 0.1", pos_3: PLATE-ID = 024K equinox: 2000.0 rv_or_z: V=+8930 comment_1: COORDS ARE ~HALFWAY BETWEEN CENTRAL comment_2: KNOT AND OUTER RING, TO NORTHWEST comment_3: OF CENTRAL COMPONENT (KNOT) INSIDE comment_4: THE OUTER RING. TWO SMALL GALAXIES comment_5: LIE ~40" TO THE NE, OUTSIDE THE comment_6: RING. ONE MAY HAVE MADE THE RING. fluxnum_1: 1 fluxval_1: V = 14.0 +/- 0.5 ! targnum: 2 name_1: IIZW28 descr_1: E,301,320 pos_1: RA = 05H 01M 42.037S +/- 0.1S, pos_2: DEC = +03D 34' 25.20" +/- 0.1", pos_3: PLATE-ID = 04YO equinox: 2000.0 rv_or_z: V=+8650 comment_1: COORDS ARE NOT CENTERED ON THE comment_2: BRIGHTEST KNOT, BUT RATHER IN comment_3: CENTER OF RING ON SIDE OF KNOT. fluxnum_1: 1 fluxval_1: V = 15.3 +/- 0.5 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 1.000 targname: AM0035-335 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F450W num_exp: 2 time_per_exp: 800S priority: 1 param_1: CR-SPLIT=NO req_1: CYCLE 4 / 1-4.5; req_2: POS TARG +10,-22; req_3: GROUP 1-4.5 NO GAP; req_4: SAME ORIENT FOR 2-4.5 AS 1; req_5: ORIENT 338D +/- 15D; comment_1: THIS PREFERRED POSITION AND ORIENT comment_2: PLACES THE CENTRAL COMPONENT ON WF3, comment_3: THE OUTER RING ON WF3 & WF4, AND THE comment_4: TWO NEARBY GALAXIES ON WF2. THE FIXED comment_5: TARGET LIST COORDS ARE PLACED AT A comment_6: POSN ON WF3-WF4 BORDER 32" FROM APEX. ! linenum: 2.000 targname: AM0035-335 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F450W num_exp: 2 time_per_exp: 800S priority: 1 param_1: CR-SPLIT=NO req_1: POS TARG +12,-21; comment_1: OFFSET 2 ARCSEC IN X AND 1 ARCSEC IN comment_2: Y TO REMOVE POSSIBLE EFFECTS ASSOC comment_3: WITH INDIVIDUAL PIXELS ETC. FIXED TARG comment_4: LIST COORDS ARE NOW 2" FROM WF3-WF4 comment_5: BORDER IN X, ON WF4, AND ~31" IN Y comment_6: FROM THE APEX OF THE PYRAMID. ! linenum: 3.000 targname: AM0035-335 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F814W num_exp: 1 time_per_exp: 400S priority: 1 param_1: CR-SPLIT=NO req_1: POS TARG +10,-22; comment_1: THE FIXED TARGET LIST COORDS ARE comment_2: PLACED ON THE WF3-WF4 BORDER 32" comment_3: IN Y FROM APEX OF PYRAMID, EXACTLY comment_4: AS IN EXP LOG LINE 1. SLIGHTLY comment_5: SHORTER EXP TIME ALLOWS TO FIT IN comment_6: ORBIT WITHOUT BIG DROP IN S/N. ! linenum: 3.500 targname: AM0035-335 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F814W num_exp: 1 time_per_exp: 500S priority: 1 param_1: CR-SPLIT=NO req_1: POS TARG +10,-22; comment_1: THE FIXED TARGET LIST COORDS ARE comment_2: PLACED ON THE WF3-WF4 BORDER 32" comment_3: IN Y FROM APEX OF PYRAMID, EXACTLY comment_4: AS IN EXP LOG LINE 1. EXP TIME OF comment_5: 500S SHOULD NOT MAKE TOO BIG A comment_6: DIFFERENCE WHEN DOING CR REMOVAL. ! linenum: 4.000 targname: AM0035-335 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F814W num_exp: 1 time_per_exp: 500S priority: 1 param_1: CR-SPLIT=NO req_1: POS TARG +12,-21; comment_1: OFFSET 2 ARCSEC IN X AND 1 ARCSEC IN comment_2: Y TO REMOVE POSSIBLE EFFECTS ASSOC comment_3: WITH INDIVIDUAL PIXELS ETC. FIXED comment_4: TARG LIST COORDS ARE NOW 2" FROM THE comment_5: WF3-WF4 BORDER IN X, ON WF4, AND ~31" comment_6: FROM THE APEX OF THE PYRAMID IN Y. ! linenum: 4.500 targname: AM0035-335 config: WFPC2 opmode: IMAGE aperture: WFALL-FIX sp_element: F814W num_exp: 1 time_per_exp: 400S priority: 1 param_1: CR-SPLIT=NO req_1: POS TARG +12,-21; comment_1: SAME POSITION AND ORIENT AS FOR EXP comment_2: LOG LINE 4, BUT THIS EXP TIME WAS comment_3: SHORTENED SLIGHTLY TO ALLOW BETTER comment_4: FIT INTO ORBIT. S/N SHOULD NOT BE comment_5: AFFECTED MUCH BY BEING 400S INSTEAD comment_6: OF 500S WHEN DOING CR REMOVAL. ! linenum: 5.000 targname: IIZW28 config: WFPC2 opmode: IMAGE aperture: WF3 sp_element: F450W num_exp: 2 time_per_exp: 800S priority: 1 param_1: CR-SPLIT=NO req_1: CYCLE 4 / 5-10; req_2: GROUP 5-10 NO GAP; req_3: SAME ORIENT FOR 6-10 AS 5; comment_1: FIXED TARGET LIST COORDS ARE TO BE comment_2: PLACED AT OPTIMAL CENTER OF WF3 CHIP. comment_3: THERE IS NO PREFERRED ORIENT FOR THIS comment_4: TARGET, BUT ALL DATA IN ALL FILTERS comment_5: SHOULD BE TAKEN AT THE SAME ORIENT. ! linenum: 6.000 targname: IIZW28 config: WFPC2 opmode: IMAGE aperture: WF3 sp_element: F450W num_exp: 2 time_per_exp: 800S priority: 1 param_1: CR-SPLIT=NO req_1: POS TARG +1,+2; comment_1: OFFSET 1 ARCSEC IN X AND 2 ARCSEC IN comment_2: Y TO REMOVE POSSIBLE EFFECTS ASSOC comment_3: WITH INDIVIDUAL PIXELS ETC. ! linenum: 7.000 targname: IIZW28 config: WFPC2 opmode: IMAGE aperture: WF3 sp_element: F814W num_exp: 1 time_per_exp: 400S priority: 1 param_1: CR-SPLIT=NO comment_1: FIXED TARGET LIST COORDS ARE AT THE comment_2: OPTIMAL CENTER OF WF3. USE SAME ORIENT comment_3: AS THAT FOR F450W AND F673N EXPOSURES. ! linenum: 7.500 targname: IIZW28 config: WFPC2 opmode: IMAGE aperture: WF3 sp_element: F814W num_exp: 1 time_per_exp: 500S priority: 1 param_1: CR-SPLIT=NO comment_1: FIXED TARGET LIST COORDS ARE AT THE comment_2: OPTIMAL CENTER OF WF3. USE SAME ORIENT comment_3: AS THAT FOR F450W AND F673N EXPOSURES. ! linenum: 8.000 targname: IIZW28 config: WFPC2 opmode: IMAGE aperture: WF3 sp_element: F814W num_exp: 1 time_per_exp: 500S priority: 1 param_1: CR-SPLIT=NO req_1: POS TARG +1,+2; comment_1: OFFSET 1 ARCSEC IN X AND 2 ARCSEC IN comment_2: Y TO REMOVE POSSIBLE EFFECTS ASSOC comment_3: WITH INDIVIDUAL PIXELS ETC. ! linenum: 8.500 targname: IIZW28 config: WFPC2 opmode: IMAGE aperture: WF3 sp_element: F814W num_exp: 1 time_per_exp: 400S priority: 1 param_1: CR-SPLIT=NO req_1: POS TARG +1,+2; comment_1: OFFSET 1 ARCSEC IN X AND 2 ARCSEC IN comment_2: Y TO REMOVE POSSIBLE EFFECTS ASSOC comment_3: WITH INDIVIDUAL PIXELS ETC. ! linenum: 9.000 targname: IIZW28 config: WFPC2 opmode: IMAGE aperture: WF3 sp_element: F673N num_exp: 4 time_per_exp: 1000S priority: 1 param_1: CR-SPLIT=NO comment_1: FIXED TARGET LIST COORDS ARE AT THE comment_2: OPTIMAL CENTER OF WF3. USE SAME ORIENT comment_3: AS THAT USED FOR ALL F450W AND F814W comment_4: EXPOSURES. ! linenum: 9.500 targname: IIZW28 config: WFPC2 opmode: IMAGE aperture: WF3 sp_element: F673N num_exp: 2 time_per_exp: 1000S priority: 1 param_1: CR-SPLIT=NO req_1: POS TARG +1,+2; comment_1: OFFSET 1 ARCSEC IN X AND 2 ARCSEC IN comment_2: Y TO REMOVE POSSIBLE EFFECTS ASSOC comment_3: WITH INDIVIDUAL PIXELS ETC. ! linenum: 10.000 targname: IIZW28 config: WFPC2 opmode: IMAGE aperture: WF3 sp_element: F673N num_exp: 2 time_per_exp: 900S priority: 1 param_1: CR-SPLIT=NO req_1: POS TARG +1,+2; comment_1: OFFSET 1 ARCSEC IN X AND 2 ARCSEC IN comment_2: Y TO REMOVE POSSIBLE EFFECTS ASSOC comment_3: WITH INDIVIDUAL PIXELS ETC. EXPOSURE comment_4: TIME SHORTENED SLIGHTLY TO FIT TAC comment_5: ALLOCATION. SHOULD NOT MAKE MUCH comment_6: DIFFERENCE FOR CR DETECTION & REMOVAL. ! ! end of exposure logsheet ! No scan data records found