7452( 11) - 11/20/97 12:02 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 7452 Version: 11 Check-in Date: 20-Nov-1997 12:01:25 1.Proposal Title: NICMOS imaging of MuJy radio sources with R>= 29: The birth of AGN in pregalactic objects at z>=6-10? ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 7 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Rogier Windhorst ARIZONA STATE UNIVERSITY CoI: Stephen Odewahn Arizona State University, Tempe N CoI: Sam Pascarelle Arizona State University, Tempe N CoI: Ed Fomalont NRAO, Charlottesville N CoI: Ken Kellermann NRAO, Charlottesville N CoI: R. Bruce Partridge Haverford College, Haverford N CoI: Eric Richards University of Virginia, Charlottesville N ------------------------------------------------------------------------------------ 5. Abstract We request 14 primary orbits with NICMOS in Cycle 7 to image two faint radio sources from our microJansky surveys that remained optically unidentified at R>= 29 mag (I>=28.5). We show that at brighter optical levels microJy sources have luminosities of L(star)+/-1 mag. Hence, unidentified sources with R>= 29 mag are most likely at z>=6. One of these unidentified sources is in the Hubble Deep Field, only 13'' (~ 100 kpc) away from four very red objects in UBVI which Lanzetta et al. (1996) suggested may be galaxies at z>=6. In the light of our recent HST discovery of a cluster of 18 sub- galactic sized objects at z~2.4, our hypothesis is that galaxy formation proceeded from rapid CDM-like merging of compact ``sub-galactic clumps'' that started at z~5--10 (Pascarelle et al. 1996). We argue that these unidentified microJy radio sources mark the onset of AGN activity in a small grouping of ~5 pre- galactic objects at z>=6, with the radio source being the most obscured. NICMOS/NIC2 images in the high throughput filters F110W & F160W are imperative to futher investigate these objects. The images will be made public and will be used to: (1) determine their kpc sizes and optical- IR colors; (2) find any obscured AGN, and see what causes the radio emission; (3) constrain their possible redshift range and the role of dust; (4) find the sub-galactic fragments suitable for NICMOS-grism Cy 8 follow-up to determine their redshifts. ------------------------------------------------------------------------------------ 7452( 11) - 11/20/97 12:02 - [ 2] Observations Description ------------------------ (1) Filter selection: Because of the small expected angular sizes, the NICMOS images have to be taken with NIC1 or NIC2. Unless the objects are at z>=13, most of the flux will not be blanked out by the Lyman discontinuity shifted into F110W. For z>=6, both F160W and F110W will look below 2500 Ang in the restframe, where the extinction does not vary greatly with wavelength. Simulations with the WWW tool show that NIC2+F110W and F160W yield by far the most efficient combination for broad-band detection. (2) Time justification and feasibility: A marginal signal is seen at the VLA position in the HDF I-band catalog with I_AB=29.06 mag, but it is too faint to be called a real detection or be part of the complete sample of Williams et al. 1996. If we assume that the VLA source has I~29.0 mag, then Fig. 3a shows that at z>=6 the object will likely have (I--K)>=1.3 and K<27.7 mag. Assuming a worst case (J--K)~0.4 mag (at z=7 from BC93), we find J<27.3 mag, or F_nu > 1.9*10^-8 Jy. The WWW tool predicts a 4-sigma detection in 20,000 sec. Similarly, we predict H~<26.5 mag or F_nu>1.9* 10^-8 Jy, and a 2.2-sigma detection in 20,000 sec. (Pushing to 4- sigma would be unrealistic at this stage, until we know more about the object). With two 2500 sec exposures per orbit in this CVZ field, we can do 8 exposures in both filters in 9 orbits, including aquisition and overhead. The radio source with the R>=28 limit in the 14h+52deg field will take about 6,000 sec in F110W and 9000 sec in F160W, for a total of 5 orbits (border of CVZ), assuming that it is a bit brighter optically, as it is in the radio. We note that objects at z>=5 will have an enormous cosmological SB -dimming proportional to (1+z)^4, but we emphasize that this is only true if the objects are resolved. In fact, many of the FBG's seen in the HDF and other deep HST fields are essentially unresolved by the HST PSF (Odewahn et al. 96, Pascarelle et al. 1996b). This could reflect the rapid increase of the merger rate with z, so that smaller and smaller sub-clumps are seen at higher z, helping to make our z>=4 candidates essentially unresolved even at the HST NICMOS resolution, and so mitigate the tremendous SB-dimming. Real Time Justification ----------------------- We have no special requirements for our Cycle 7 observations. (1) Ground-based spectroscopy: We will use the MMT 6.5 meter after it comes online in Dec. 1997 to trace redshifted Ly-alpha out to 9000 Ang (z<6.4) with the Red Spectrograph and with an OH-suppressing IR-spectrograph out to 2.3 micron, which will allow us to trace O II 3727 to z~5.3 and Ly-alpha even further, once we have an idea of the z-range from the WFPC2-NICMOS colors. Calibration Justification ------------------------- Real_Time_Justification Additional Comments ------------------- The Program Coordinator (Molly Shea) and Contact Scientist (Luis Colina) have been informed that our NIC2 target is just OUTSIDE the edge of the NIC3 survey that the NICMOS GTO team is doing in the HDF, as listed in the GTO position catalog. I have been in close contact with Rodger Thompson about this, and he has encouraged me to go ahead with my program, and stay in touch should conflicts arise from overlapping parallels with NIC1, NIC3 due to different ORIENTS being used. Rodger Thompson is in fact interested to see the G110W, G140W parallels attached to my program (see his Email attached below), and so are we advice what else we can do to avoid such a conflict. Is the ORIENT of the GTO NIC3 exposures known, so I can avoid overlap from my parallels by using a ORIENT TO ? ===> If possible, and if not posing undue scheduling constraints, please schedule P7452 at an ORIENT equal to that of the NICMOS GTO team NIC3 exposures in the HDF PLUS 180 degrees (+/-60 degress), such that our NIC2 observations will occur about half a year later than the NICMOS GTO observations, thereby likely minimizing the overlap between the NIC1, 3 parallels, and maximizing the science return for all involved. =============================================================================== = From: SMTP%"thompson@as.arizona.edu" 5-MAR-1997 07:55:44.97 To: RAW CC: Subj: Re: NICMOS GO time in the HDF Rogier, Perhaps the best for all would be to collaborate on the camera 3 parallels assuming they are in focus which will depend on the focus history. If you could use th G096 or G141 grism as the camera 3 parallel we might find some useful stuff. That way you would not have to worry about your orient and could maximize it for your benefit. In some cases there may not be much choice due to the limited guide star selection in the area. Rodger =============================================================================== QUESTION: As per my telesphone conversation with Luis Colina, I am not sure that I have optimally implemented the scheduling the attached pure parallels without reducing the efficiency of our primary program. Please feel free to modify the attached parallels, as long as the primary science efficiency is not greatly impacted. (b) I seem to have trouble filling up the last part of the last orbit in each visit (i.e. orbits 5 and 9 out of 9), while I ask for the SAME in those orbits as in all the others. What should I do? ------------------------------------------------------------------------------------ 7452( 11) - 11/20/97 12:02 - [ 3] Data Distribution Media: DAT Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 7452( 11) - 11/20/97 12:02 - [ 4] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 HDF-VLA- UNIDENTIFIED RA=12H 36M 42.092S +/- 0.1", J2000.0 z=8.0 V = 29.5 3642+1331 DEC= +62D 13' 31.46" +/- 0.1", B-V = 0.0 PLATE-ID=01R1 J = 27.0 H = 26.0 Comments: Coordinates are based on VLA FK5 positions 7452( 11) - 11/20/97 12:02 - [ 5] Visit: 01 Visit Priority: Visit Requirements: CVZ 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 ------------------------------------------------------------------------------------------------------------------------------------ 110 HDF-VLA-364 NIC2 MULTIAC NIC2 F110W 11035 PATTERN=SPIRAL-DITH,NUM-POS=3, 1 DEF PARallel 111-112 WITH 110 2+1331 CUM DITH-SIZE=1.3125,SAMP-SEQ=MIF1024 ,NSAMP=25 Comments: Place (RA,DEC) IN MOST SENSITIVE, CLEAN PART OF NIC2, NOT NECESSARILY EXACTLY IN THE MIDDLE OF NIC2. HOWEVER, DON'T MOVE IT TOO FAR FROM THE MIDDLE OF NIC2, OR MAY LOOSE THE TARGET ALTOGETHER ------------------------------------------------------------------------------------------------------------------------------------ 111 HDF-VLA-364 NIC3 MULTIAC NIC3 F110W 11035 SAMP-SEQ=SPARS256,NSAMP=6 1 DEF 2+1331 CUM Comments: Please adjust parallel exposure times downward to fit inside primary exposure times of 1026.4 sec. ------------------------------------------------------------------------------------------------------------------------------------ 112 HDF-VLA-364 NIC1 MULTIAC NIC1 F110W 11035 SAMP-SEQ=SPARS256,NSAMP=6 1 DEF 2+1331 CUM Comments: Please adjust parallel exposure times downward to fit inside primary exposure times of 1026.4 sec. ------------------------------------------------------------------------------------------------------------------------------------ 120 HDF-VLA-364 NIC2 MULTIAC NIC2 F110W 11035 PATTERN=SPIRAL-DITH,NUM-POS=3, 4 DEF PARallel 121-122 WITH 120 2+1331 CUM DITH-SIZE=1.3125,SAMP-SEQ=MIF1024 ,NSAMP=25 Comments: Place (RA,DEC) IN MOST SENSITIVE, CLEAN PART OF NIC2, NOT NECESSARILY EXACTLY IN THE MIDDLE OF NIC2. HOWEVER, DON'T MOVE IT TOO FAR FROM THE MIDDLE OF NIC2, OR MAY LOOSE THE TARGET ALTOGETHER ------------------------------------------------------------------------------------------------------------------------------------ 121 HDF-VLA-364 NIC3 MULTIAC NIC3 G096 09911 SAMP-SEQ=SPARS256,NSAMP=6 4 DEF 2+1331 CUM Comments: Please adjust parallel exposure times downward to fit inside primary exposure times of 1026.4 sec. ------------------------------------------------------------------------------------------------------------------------------------ 122 HDF-VLA-364 NIC1 MULTIAC NIC1 F110W 11035 SAMP-SEQ=SPARS256,NSAMP=6 4 DEF 2+1331 CUM Comments: Please adjust parallel exposure times downward to fit inside primary exposure times of 1026.4 sec. F160W+G141): ------------------------------------------------------------------------------------------------------------------------------------ 7452( 11) - 11/20/97 12:02 - [ 6] Visit: 02 Visit Priority: Visit Requirements: CVZ On Hold Comments: Additional Comments: pREFER YOU IMPLEMENT SAME ORIENTation AS 1, BUT ONLY IF IT DOES NOT PREVENT SCHEDULING OTHERWISE, USE ANY ORIENT FOR VISIT 2 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 210 HDF-VLA-364 NIC2 MULTIAC NIC2 F160W 15931 PATTERN=SPIRAL-DITH,NUM-POS=5, 1 DEF PARallel 211-212 WITH 210 2+1331 CUM DITH-SIZE=1.3125,SAMP-SEQ=MIF1024 ,NSAMP=25 Comments: Place (RA,DEC) IN MOST SENSITIVE, CLEAN PART OF NIC2, NOT NECESSARILY EXACTLY IN THE MIDDLE OF NIC2. HOWEVER, DON'T MOVE IT TOO FAR FROM THE MIDDLE OF NIC2, OR MAY LOOSE THE TARGET ALTOGETHER ------------------------------------------------------------------------------------------------------------------------------------ 211 HDF-VLA-364 NIC3 MULTIAC NIC3 F160W 15931 SAMP-SEQ=SPARS256,NSAMP=6 1 DEF 2+1331 CUM Comments: Please adjust parallel exposure times downward to fit inside primary exposure times of 1026.4 sec. ------------------------------------------------------------------------------------------------------------------------------------ 212 HDF-VLA-364 NIC1 MULTIAC NIC1 F160W 15931 SAMP-SEQ=SPARS256,NSAMP=6 1 DEF 2+1331 CUM Comments: Please adjust parallel exposure times downward to fit inside primary exposure times of 1026.4 sec. ------------------------------------------------------------------------------------------------------------------------------------ 220 HDF-VLA-364 NIC2 MULTIAC NIC2 F160W 15931 PATTERN=SPIRAL-DITH,NUM-POS=3, 9 DEF PARallel 221-222 WITH 220 2+1331 CUM DITH-SIZE=1.3125,SAMP-SEQ=MIF1024 ,NSAMP=25 Comments: Place (RA,DEC) IN MOST SENSITIVE, CLEAN PART OF NIC2, NOT NECESSARILY EXACTLY IN THE MIDDLE OF NIC2. HOWEVER, DON'T MOVE IT TOO FAR FROM THE MIDDLE OF NIC2, OR MAY LOOSE THE TARGET ALTOGETHER ------------------------------------------------------------------------------------------------------------------------------------ 221 HDF-VLA-364 NIC3 MULTIAC NIC3 G141 15100 SAMP-SEQ=SPARS256,NSAMP=6 9 DEF 2+1331 CUM Comments: Please adjust parallel exposure times downward to fit inside primary exposure times of 1026.4 sec. ------------------------------------------------------------------------------------------------------------------------------------ 222 HDF-VLA-364 NIC1 MULTIAC NIC1 F160W 15931 SAMP-SEQ=SPARS256,NSAMP=6 9 DEF 2+1331 CUM Comments: Please adjust parallel exposure times downward to fit inside primary exposure times of 1026.4 sec. ------------------------------------------------------------------------------------------------------------------------------------ 7452( 11) - 11/20/97 12:02 - [ 7] Summary Form for Proposal 7452 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations NIC2 NIC3 NIC1 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters PATTERN=SPIRAL-DITH NUM-POS=3 DITH-SIZE=1.3125 SAMP-SEQ=MIF1024 NSAMP=25 NSAMP=6 SAMP-SEQ=SPARS256 NUM-POS=5 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements CVZ PARallel 111-112 WITH 110 PARallel 121-122 WITH 120 PARallel 211-212 WITH 210 PARallel 221-222 WITH 220 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F110W G096 F160W G141 ------------------------------------------------------------------------------------------------------------------------------------ Target Names HDF-VLA-3642+1331 ------------------------------------------------------------------------------------------------------------------------------------