! File: 5470P.PROP ! Database: PEPDB ! Date: 20-OCT-1993:15:46:14 coverpage: title_1: WFPC2 IMAGING OF THE PROTOGALAXY CANDIDATE B2 0902+34 title_2: -LRF Observations sci_cat: GALAXIES & CLUSTERS sci_subcat: DISTANT GALAXIES proposal_for: GO cont_id: 5470 pi_fname: PETER pi_mi: R pi_lname: EISENHARDT pi_inst: JPL pi_country: USA pi_phone: 818-354-4395 hours_pri: 14.01 num_pri: 1 wf_pc: Y off_fname: CHARLES off_lname: ELACHI off_title: ASST. LAB. DIRECTOR off_inst: 2370 off_addr_1: JET PROPULSION LABORATORY off_addr_2: M/S 180-704 off_addr_3: 4800 OAK GROVE DRIVE off_city: PASADENA off_state: CA off_zip: 91109 off_country: USA off_phone: (818) 354 5673 ! end of coverpage abstract: line_1: We propose to obtain high spatial resolution imaging with WFPC2 of the line_2: continuum and Ly-alpha line emission from the distant radio galaxy B2 line_3: 0902+34. This object appears to have the largest UV to optical (rest line_4: frame) flux ratio measured for a radio galaxy, and at z=3.395 is also line_5: among the most distant galaxies known. It is therefore an excellent line_6: candidate for a protogalaxy. Our objective is to obtain a clearer picture line_7: of the formation process in this galaxy. The proposed observations will line_8: reveal the distribution of star-forming regions and emission line gas, line_9: and the relationship between them, on a 1 kpc scale, as well as their line_10: relationship to the radio source structure. ! ! end of abstract general_form_proposers: lname: EISENHARDT fname: PETER mi: R inst: 2370 country: USA ! lname: LILLY fname: SIMON inst: 4664 country: CANADA ! lname: LU fname: NANYAO mi: Y inst: 2370 country: USA ! lname: DICKINSON fname: MARK inst: 3470 country: USA ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: This is a continuation of proposal 5470 (which used the Planetary line_2: Camera and F622W to measure the rest frame UV continuum in B2 0902+34.) line_3: Here we propose to obtain a total of 6.1 hours of integration with the line_4: linear ramp filter, placing B2 0902+34 as close as possible to the 5341 line_5: Angstrom position while keeping the target at least 3.5 arcsec from the line_6: edge of the WF4 array, to measure the redshifted Ly alpha morphology. line_7: Because of misalignment between the LRF and WFPC2 detectors, the best line_8: way to achieve this without significant changes in WFPC2 operations is line_9: to use a +15 degree SOFA rotation and position B2 0902+34 at 5324 line_10: Angstroms on ramp 2 of FR533N of the LRF. This places B2 0902+34 line_11: at pixel 763, 574, about 3.7 arcsec above the bottom of WF4. The line_12: integration times of 22000 seconds through the LRF will be broken into line_13: three groups, separated by integer numbers of WF4 pixels to avoid bad line_14: pixels, each group with 3 or 4 2200 second exposures. We use 2200 seconds line_15: as our estimate for the maximum available unocculted time per orbit, line_16: but because all of our observations will be read-noise limited, line_17: we hope that the actual per orbit exposure time can be adjusted to its line_18: maximum allowable length (within the constraint of the line_19: total spacecraft time allocation) in order to maximize our line_20: resulting S/N. The three exposures taken within each FGS lock line_21: position will suffice to allow cosmic ray removal, thus we set line_22: CRSPLIT=NO. The exposures taken through each filter should be line_23: obtained on consecutive orbits. ! question: 4 section: 1 line_1: Figure 2 of section 2 of our Phase I proposal illustrates deep line_2: (hours of KPNO 4m time) subarcsec line_3: imaging in narrow and broadband filters of B2 0902+34. line_4: We have also line_5: obtained deep optical and near IR spectra, which confirm line_6: the corrections for line emssion to the continuum flux, line_7: and result in a flat, line-free line_8: continuum characteristic of a protogalaxy. line_9: Both the flat (young) SED and line_10: figure 2 suggest there is complex structure within the line_11: central 2 " of the source, corresponding to roughly 14 kpc. line_12: Detecting whether there are two subcomponents or many line_13: (many subcomponents are plausible for a dynamically young object) line_14: requires significantly better spatial resolution than Figure line_15: 2 provides, or is currently feasible from the ground, line_16: while HST's ability line_17: to resolve 1kpc scales is well matched to the expected substructure. line_18: We will propose to obtain space IR measurements of this object line_19: from ISO and SIRTF, when they become available. ! question: 6 section: 1 line_1: Our original proposal (GO 5470) to image the redshift 3.4 line_2: protogalaxy candidate B2 0902+34 in the UV continuum and line_3: in redshifted Lyman alpha at 5341 Angstroms has encountered line_4: difficulties due to misalignments in the WFPC2 linear ramp line_5: filter (LRF), which cause certain wavelength positions on the line_6: LRF to miss the WFPC detectors. This misalignment leads to gaps line_7: in the LRF wavelength coverage and 5341 Angstroms is unfortunately line_8: near the center of the largest gap. These gaps were not known line_9: at the time of cycle 4 proposals, but are summarized in Table 3.8 line_10: of the Version 2.0 WFPC2 Instrument handbook distributed for Cycle 5. line_11: I have discussed this problem at some length both with my line_12: collaborators and with Dr. Robin Evans of JPL, who is the line_13: expert on the LRF for the JPL WFPC2 team. To summarize: line_14: ************************************************************ line_15: * We request that the observation be made by positioning * line_16: * B2 0902+34 at the 5324 Angstrom position on the LRF when * line_17: * rotated to +15 degrees. * line_18: ************************************************************ line_19: Enabling the +15 degree LRF rotation would plug the single line_20: largest gap in the LRF wavelength coverage, and line_21: thus could be expected to benefit other proposals as well. line_22: We therefore believe this request is consistent with existing policy line_23: as stated in both versions 1.0 and 2.0 of the WFPC2 question: 6 section: 2 line_1: instrument handbook: "...the linear ramp filters require partial line_2: rotation of the SOFA wheels to -18 and -33 degrees from their line_3: nominal positions, to recover wavelength regions which would line_4: fall on the PC camera or otherwise be lost." The +15 degree line_5: rotation of the SOFA wheels is supported for the polarizer line_6: quad filter as shown in Table 3.10 of version 2.0 of the line_7: handbook, placing it in the same category as -18 and -33 line_8: degrees. line_9: My collaborators and I agree that the scientific importance line_10: of the Lyman alpha image is very high and that we should line_11: attempt to obtain it if at all possible. The observed equivalent line_12: width of the line is roughly 1000 Angstroms, and its spatial line_13: distribution is of great interest both as a tracer of the material line_14: available for star formation and of the ionizing continuum. line_15: The Lyman alpha morphology is known to be complex from groundbased line_16: imaging obtained by Mark Dickinson and Hy Spinrad (see Figure 1 line_17: of Eisenhardt and Dickinson, Ap.J. Letters 399, L47). The spatial line_18: extent of the higher surface brightness Lyman emission is about line_19: 7 arcsec in diameter, as shown in that figure. line_20: This spatial extent means that we need to position B2 0902+34 line_21: at least 3.5 arcsec onto the WFPC (this is a bare minimum as line_22: astrometric uncertainties as well as residual uncertainty about the question: 6 section: 3 line_1: LRF position of order one arcsec are present). With this criterion the line_2: closest available LRF wavelength without the +15 degree rotation line_3: is at 5377 Angstroms (on LRF ramp 3 at 0 degrees rotation), Which line_4: Dr. Evans calculates will fall at pixel 762, 292 on the WF4 chip, line_5: 3.8 arcsec from the bottom of the chip.Dr. Evans calculates the line_7: transmission of the LRF at this position to 5341 Angstrom light will be line_8: one half of the value which we based our exposure time calculations. line_9: Lyman alpha regions further away from the edge of WF4 will have lower line_10: transmission -only 25% of the peak value at points 7 arcsec from the line_11: chip edge.This will lead to a compromised Lyman alpha observation line_12: which is difficult to calibrate and interpret. line_13: However, with a +15 degree rotation (a SOFA rotation analagous to line_14: -18 or -33 in that it is supported for the polarizer quad filter) line_15: B2 0902+34 could be positioned at 5324 Angstroms on ramp 2 of FR533N of line_16: the LRF, falling at pixel 763, 574, about 3.7 arcsec above the bottom of line_17: WF4. The Lyman alpha transmission in this case would be about 93% of the line_18: peak value, falling to about 80% 7 arcsec from the chip edge. This line_19: Lyman alpha observation would be quite satisfactory. line_20: An option we rejected was to use F547M, which is the narrowest standard line_21: filter which includes 5341. Because F547M has a FWHM of 600 Angstroms line_22: it would be very difficult to disentangle the UV continuum contribution line_23: from the Lyman alpha emission in this filter. question: 7 section: 1 line_1: The major hurdle in reducing HST data prior to Cycle 4, i.e line_2: correcting for the degraded PSF function, will not be line_3: necessary with WFPC2. Following pipeline processing, we will line_4: devote special attention in the reduction process to cosmic line_5: ray (CR) removal. CR detection will be aided by the triply line_6: redundant images at each array location, and in the case of line_7: the continuum observations with the Planetary Camera by the line_8: distinct unresolved character of the CR PSF. We have line_9: developed software within IRAF specifically designed to line_10: detect and remove CR's from deep ground based exposures. We line_11: also have experience in accurately determining sky levels line_12: (crucial in IR photometry) and have dveloped software for line_13: this purpose as well. The Lya image will need to be line_14: corrected for continuum in the 1% bandpass of the LRF. We line_15: will scale our continuum filter image for this purpose, a line_16: procedure we have used successfully on similar groundbased line_17: data. If only a few compact well detected sources are line_18: evident at this point, we will attempt to fit and subtract line_19: PSF's to search for fainter neighboring components. We will line_20: perform surface brightness analysis on prominent components line_21: in a fashion simlar to that used by Windhorst et al. (1992). line_22: All data reduction and analysis will be done within IRAF/SDAS line_23: with which we have extensive experience. ! question: 9 section: 1 line_1: 4575 "WF/PC Observations of the Most Luminous Galaxy in the line_2: Universe; the IRAS Source FSC 10214+4724", Peter Eisenhardt coI line_3: 1229 - "OPTICAL AND ULTRAVIOLET IMAGING OF LARGE REDSHIFT line_4: RADIO GALAXIES " S.Lilly coI line_5: 2365 - "HST IMAGING OF GROUND-BASED ULTRA-DEEP SURVEY FIELDS line_6: Simon J. Lilly PI line_7: 2684-KP - "HST MEDIUM-DEEP SURVEY: CYCLE 1 OBSERVATIONS line_8: S.Lilly coI (continuations in 4018, 4029, 4105, 4106) line_9: 2695 - "MORPHOLOGY OF PKS 1614+051, A QUASAR-GALAXY PAIR AT line_10: Z=3.21 M.Dickinson coI line_11: 2698 - "LYMAN-ALPHA IMAGING OF YOUNG AND FORMING GALAXIES AT line_12: LARGE REDSHIFTS " M.Dickinson coI line_13: 3543 - "THE DEEP ULTRAVIOLET SKY ", Simon J. Lilly PI line_14: 3654 - "HIGH RESOLUTION MORPHOLOGIES AND COLORS IN DISTANT line_15: RADIO GALAXIES "M.Dickinson coI line_17: None are directly related to this proposal. line_19: No results have yet been published. ! question: 10 section: 1 line_1: Sun workstations at JPL, U of Toronto, and UC Berkeley. line_2: However we expect to need one additional SPARCstation LX line_3: and 1GB disk drive and have budgeted 50% of this cost to line_4: STScI, with the remainder coming from JPL funds. Op line_5: We have IRAF/SDAS installed and have developed numerous software line_6: routines relevant to the data reduction and analysis which we line_7: will apply (see Section 7.) ! !end of general form text general_form_address: lname: Eisenhardt fname: Peter mi: R category: PI inst: 2370 addr_1: MS 169-327 addr_2: Jet Propulsion Laboratory addr_3: 4800 Oak Grove Drive city: Pasadena state: CA zip: 91109 country: USA phone: 818-354-4395 telex: prme@kromos.jpl.nasa.gov ! lname: category: CON ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: B20902+34 descr_1: E,315,322,325 pos_1: RA = 9H 2M 24.80S +/- 0.03S, pos_2: DEC = +34D 19' 57.0" +/- 0.3" equinox: 1950 rv_or_z: Z = 3.395 comment_1: OBSERVED R AND 5342 FLUXES 100 comment_2: TIMES LARGER BUT EXTENDED OVER comment_3: SEVERAL ARCSEC. GOAL IS S/N=5 comment_4: ON UNRESOLVED STRUCTURES WITH comment_5: 1% OF OBSERVED TOTAL FLUXES. comment_6: OUR GROUNDBASED IMAGES SHOW comment_7: MUCH SUBSTRUCTURE IN THIS OBJECT. fluxnum_1: 1 fluxval_1: R=28.5 fluxnum_2: 2 fluxval_2: F-LINE(5342)=30 +/- 5 E-18 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 4.000 targname: B20902+34 config: WFPC2 opmode: IMAGE aperture: LRF sp_element: LRF wavelength: 5341 num_exp: 4 time_per_exp: 2200.00S s_to_n: 5 s_to_n_time: 18000S fluxnum_1: 2 priority: 1 param_1: CR-SPLIT = NO req_1: GROUP 4-6 NO GAP; req_2: POS TARG +0.00, +0.10; req_3: CYCLE 4 / 4-6; comment_1: ADJUST EXP TIME +INFINITY/-10% TO FIT comment_2: IN AN ALIGNMENT. 3 EXP/POS FOR CR comment_3: DETECTION, UNINTERRUPTED EXPOSURES comment_4: NEEDED TO ACHIEVE DESIRED S/N. comment_5: POS TARG SEQUENCE WITH INTEGER PIXEL comment_6: SHIFTS TO AVOID PATTERN NOISE. ! linenum: 5.000 targname: B20902+34 config: WFPC2 opmode: IMAGE aperture: LRF sp_element: LRF wavelength: 5341 num_exp: 3 time_per_exp: 2200.00S s_to_n: 5 s_to_n_time: 18000S fluxnum_1: 2 priority: 1 param_1: CR-SPLIT = NO req_1: POS TARG -0.200, -0.100 comment_1: ADJUST EXP TIME +INFINITY/-10% comment_2: TO FIT IN AN ALIGNMENT. SECOND POS comment_3: TO AVOID PATTERN NOISE. FOR ALL 3 POS comment_4: USE SAME OPTIMUM CENTER BUT NOTE THAT comment_5: POS TARG REQT DOES NOT IMPLY A NEED comment_6: FOR ABSOLUTE POINTING ACCURACY < 1" ! linenum: 6.000 targname: B20902+34 config: WFPC2 opmode: IMAGE aperture: LRF sp_element: LRF wavelength: 5341 num_exp: 3 time_per_exp: 2200.00S s_to_n: 5 s_to_n_time: 18000S fluxnum_1: 2 priority: 1 param_1: CR-SPLIT = NO req_1: POS TARG +0.100, -0.200 comment_1: ADJUST EXP TIME +INFINITY/-10% comment_2: TO FIT IN AN ALIGNMENT. comment_3: THIRD POS TO AVOID BLEMISHES comment_4: ALWAYS USE +15 DEG SOFA ROT. ! ! end of exposure logsheet ! No scan data records found