8167( 4) - 05/14/99 14:34 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8167 Version: 4 Check-in Date: 09-Mar-1999 10:54:19 1.Proposal Title: WFPC2 Imaging of a Galaxy at z = 5.34 and its Field ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 8 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Daniel Stern University of California, Berkeley CoI: Prof. Hyron Spinrad University of California, Berkeley N CoI: Dr. Andrew Bunker University of California, Berkeley N CoI: Prof. James Graham University of California, Berkeley N CoI: Mr. Michael Liu University of California, Berkeley N CoI: Mr. Andrew Zirm The Johns Hopkins University N CoI: Dr. Frederick Chaffee The W.M. Keck Observatory N CoI: Dr. Rob Ivison University College London N CoI: Dr. Arjun Dey National Optical Astronomy Observatories N ------------------------------------------------------------------------------------ 5. Abstract We propose to obtain deep WFPC2 images of a galaxy at z=5.34 and its surrounding field. The galaxy, 0140+326 RD1, was the first spectroscopically confirmed object at z > 5 and among the few confirmed objects at z > 5 currently. Our goals are to (1) map the Ly-alpha line-emitting region, (2) study the restframe UV continuum morphology, (3) search for companion Ly-alpha-emitting sources, and (4) study the stellar population and dust extinction in this distant system in conjunction with recently obtained NICMOS F160W images. If this galaxy is a truly primeval object in the process of forming its first generation of stars, its morphological properties can provide critical information on the earliest phases of galaxy formation. Ongoing, deep, multi-wavelength, ground-based efforts make this an ideal field for HST to underlinesimultaneously provide high-resolution morphological information on several other timely issues in extragalactic astronomy: the proposed WFPC2 pointing contains several sub-mm sources detected in a deep (~40 ksec) program with SCUBA; the most distant known radio galaxy, 6C 0140+326 at z=4.41; 2 confirmed and several candidate Lyman-break galaxies at z > 4; and several unusually red galaxies. The observations proposed here cannot be accomplished from ground-based facilities, as their success depends upon the high spatial resolution and low sky background only attainable with HST. ------------------------------------------------------------------------------------ 8167( 4) - 05/14/99 14:34 - [ 2] Observations Description ------------------------ We propose to obtain WFPC2 observations of 0140+326 RD1 through the F814W and F850LP filters. The F814W filter will sample both the Ly-alpha emission and the restframe UV continuum (approx. 1100 - 1500 Angstrom) while the F850LP filter will sample the UV continuum alone (approx. 1340 - 1580 Angstrom). Ground-based observations have detected the galaxy at similar wavelengths: I = 26.6 AB, including Ly-alpha line emission and continuum extended over ~0.5 sq. arcsec; continuum I(cont) ~ 27 AB. This suggests the surface brightness of the Ly-alpha halo is ~27 mag/sq. arcsec; 10 orbits through the F814W filter, with overheads, will probe the galaxy morphology to this surface brightness level at a S/N=0.5 per WFC2 pixel. We will bin pixels to investigate low surface brightness morphology: S/N=2 for 0.4" x 0.4" square aperture. The continuum morphology, as measured at ~ 2500 Angstrom with NICMOS, is only marginally resolved (FWHM ~ 0.3"), suggesting that the F850LP image will also be compact. We calculate that 10 orbits through the F850LP filter, with overheads, will detect compact sources at I~27 mag AB at a S/N ~ 6. This pair of filters will allow us to probe the morphology of the Ly-alpha emitting region and search for potential companion Ly-alpha-emitting objects. We note that the WFPC2 observations will allow us to probe the morphology of the galaxy with higher spatial resolution (0.1 arcsec/pixel) than recently obtained Camera 3 NICMOS F160W observations (0.2 arcsec/pixel). Co-adding the WFPC2 data will result yield a S/N ~ 6 for unresolved objects of I~28 mag AB at ~ 8500 Angstrom, and will be used for studying the optical morphologies of scientifically interesting nearby systems, such as the sub-mm system NW of 0140+326 RD1 (see Fig. 3). In summary, we request 10 orbits for the WFPC2/F814W observations and 10 orbits for the WFPC2/F850LP observations. We emphasize the importance of carrying out both observations: the F814W data will target the Ly-alpha emission line morphology of the distant galaxy, whereas the F850LP data will probe the true continuum structure. We note that STIS, although more efficient, has a smaller field of view and does not have a suitable complement of filters for this observational program. The timeliness of the proposed observations and ongoing ground-based programs with SCUBA and Keck argue against postponing these observations until ACS. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 8167( 4) - 05/14/99 14:34 - [ 3] Data Distribution Paper Products: NO Media: ELECTRONIC Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 8167( 4) - 05/14/99 14:34 - [ 4] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 0140+326RD1 GALAXY, High Redshift RA=1H 43M 41.89S +/- 0.1S, J2000 Z=5.34 I = 26.1 Galaxy DEC=32D 54' 05.1" +/- 1.0", PLATE-ID=037O Comments: I(continuum)=26.5:, SB(LyA)=26.5:/sq.arcsec 8167( 4) - 05/14/99 14:34 - [ 5] Visit: 01 Visit Priority: Visit Requirements: ORIENT 252D TO 260D On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 101 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S Comments: 1st = (0, 0) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 102 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S POS TARG 2.05, 0.2 Comments: 2nd = (20.5, 2) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 103 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S POS TARG -0.2, 2.05 Comments: 3rd = (18.5, 22.5) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 104 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S POS TARG -2.05,-0.2 Comments: 4th = (-2, 20.5) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 8167( 4) - 05/14/99 14:34 - [ 6] Visit: 02 Visit Priority: Visit Requirements: Same orient as 1 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 201 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S Comments: 1st = (0, 0) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 202 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S POS TARG -2.05,-0.2 Comments: 2nd = (-20.5,-2) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 203 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S POS TARG 0.2,-2.05 Comments: 3rd = (-18.5,-22.5) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 204 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S POS TARG 2.05, 0.2 Comments: 4th = (2,-20.5) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 8167( 4) - 05/14/99 14:34 - [ 7] Visit: 03 Visit Priority: Visit Requirements: Same orient as 1 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 301 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S Comments: 1st = (0, 0) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 302 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S POS TARG 2.05, 0.2 Comments: 2nd = (20.5, 2) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 303 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S POS TARG 0.2,-2.05 Comments: 3rd = (22.5,-18.5) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 304 0140+326RD1 WFPC2 IMAGE WF4-FIX F814W 1 2600 S POS TARG -2.05,-0.2 Comments: 4th = (2,-20.5) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 8167( 4) - 05/14/99 14:34 - [ 8] Visit: 04 Visit Priority: Visit Requirements: Same orient as 1 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 401 0140+326RD1 WFPC2 IMAGE WF4-FIX F850LP 1 2600 S Comments: 1st = (0, 0) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 402 0140+326RD1 WFPC2 IMAGE WF4-FIX F850LP 1 2600 S POS TARG 2.05, 0.2 Comments: 2nd = (20.5, 2) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 403 0140+326RD1 WFPC2 IMAGE WF4-FIX F850LP 1 2600 S POS TARG -0.2, 2.05 Comments: 3rd = (18.5, 22.5) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 404 0140+326RD1 WFPC2 IMAGE WF4-FIX F850LP 1 2600 S POS TARG -2.05,-0.2 Comments: 4th = (-2, 20.5) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 8167( 4) - 05/14/99 14:34 - [ 9] Visit: 05 Visit Priority: Visit Requirements: Same orient as 1 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 501 0140+326RD1 WFPC2 IMAGE WF4-FIX F850LP 1 2600 S Comments: 1st = (0, 0) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 502 0140+326RD1 WFPC2 IMAGE WF4-FIX F850LP 1 2600 S POS TARG -2.05,-0.2 Comments: 2nd = (-20.5,-2) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 503 0140+326RD1 WFPC2 IMAGE WF4-FIX F850LP 1 2600 S POS TARG 0.2,-2.05 Comments: 3rd = (-18.5,-22.5) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 504 0140+326RD1 WFPC2 IMAGE WF4-FIX F850LP 1 2600 S POS TARG 2.05, 0.2 Comments: 4th = (2,-20.5) WFPC2 pixels ------------------------------------------------------------------------------------------------------------------------------------ 8167( 4) - 05/14/99 14:34 - [ 10] Summary Form for Proposal 8167 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures WF4-FIX ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 252D TO 260D POS TARG 2.05, 0.2 POS TARG -0.2, 2.05 POS TARG -2.05,-0.2 Same orient as 1 POS TARG 0.2,-2.05 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F814W F850LP ------------------------------------------------------------------------------------------------------------------------------------ Target Names 0140+326RD1 ------------------------------------------------------------------------------------------------------------------------------------