8060( 3) - 07/16/98 16:36 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8060 Version: 3 Check-in Date: 16-Jul-1998 16:34:55 1.Proposal Title: Observation of the Unusual BL Lac Object/Compact Symmetric Object PKS 1413+135 ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO/DD 7 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Dr. John Stocke University of Colorado CoI: John Conway Onsala Space Observatory N CoI: Eric Perlman Space Telescope Science Institute N CoI: Mitchell Begelman University of Colorado, Boulder N CoI: Chris Reynolds University of Colorado, Boulder N ------------------------------------------------------------------------------------ 5. Abstract We propose to obtain high resolution optical (B, R) and near-IR (H) images of the cores of bright, nearby galaxies which contain powerful radio sources called ``Compact Symmetric Objects'' (CSOs). There is ample evidence that CSOs are the very young (< 10^4 yrs old) progenitors of the powerful radio galaxies like Cygnus A. But unlike virtually all other radio galaxies, most CSOs have been detected in H I 21cm absorption, indicating an unusual (for a radio galaxy) nucler environment. We propose to use the HST PC and NICMOS to image the nearest examples of CSOs to search for evidence for a recent merger of disk galaxies, creating both the ``baby Cygnus A'' and the overall elliptical morphology seen in virtually all powerful radio galaxies. Only HST can image these galaxies at the same size scale of the CSO itself, also allowing us to search for nuclear structures aligned with the radio source in this formative stage. ------------------------------------------------------------------------------------ 8060( 3) - 07/16/98 16:36 - [ 2] Observations Description ------------------------ The target of this Director's Discretionary time exposure, PKS 1413+135, has already been observed with WFPC1 in F555W. Here we propose a two-orbit observation with NICMOS/NIC1 in F160W (H band). These observations should pierce the veil of obscuration that is known to exist at shorter wavelengths in this source. This target was originally proposed as part of GO7344, but awarded to another investigator team. That investigator team subsequently mispointed. The goal of our program is to investigate the nature of these youngest of AGNs, in an attempt to determine what triggered their "turn-on" and understand their interior structure. We have chosen to use the NIC1 camera, which will yield resolutions comparable to the PC for direct comparison purposes and to search the inner nuclear region beyond the veil of the reddening. While we expect a point source to be present, we have based our integration time estimate on the observed galaxy magnitude and redshift, since the preci se amount of reddening and its dis tribution across the nuclear region is unknown. We expect to acheive signal-to-noise ratios of 30-50 per pixel in the brightest regions. The high signal-to-noise is critical to these observations given evidence based upon ground-based observations that the nuclear sources in CSOs do not emerge from their shrouds until the near-infrared (J and H band). Given the size observed on optical survey plates, the central regions of this target should fit nicely into NIC1. We are positioning the target at the geometrical center of NIC1 in order to ensure acquisition of the galaxy's nucleus (the position we are using is from VLBI observations, which have slight (1") reference frame inconsistencies with the DSS). The interesting regions of the galaxy should easily fit within the NIC1 chip, given the galaxy's redshift of z=0.247. In order to eliminate effects from the bad rows, grot, warm pixels and other image defects, we will be doing a fourfold dither to positions (1, 1), (-1,-1), (1,- 1) and (-1, 1) arcseconds fro m the NIC1-FIX aperture. Real Time Justification ----------------------- The NICMOS images will be important for comparison with the small radio structure of this source, which has been published by us (Perlman et al. 1996). We have obtained four epochs of VLBA and one epoch of HALCA observations which shows some evidence for evolution on both sides of the nucleus, making PKS1413+135 unique among extragalactic radio sources. We are proposing for continued HALCA and VLBA monitoring in 1998-1999, with frequency increasing to twice a year. This source is being mapped this summer with the VLBA in the HI absorption line to determine the details of the HI distribution in its nucleus. VLBI observations in the CO line has detected structures as small as 70 microarcseconds in the absorbing screen. ASCA observations are also scheduled to take place this summer. None of the planned supporting observations require special scheduling considerations for the HST imaging proposed herein. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 8060( 3) - 07/16/98 16:36 - [ 3] Data Distribution Media: ELECTRONIC Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 8060( 3) - 07/16/98 16:36 - [ 4] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 PKS1413+135 GALAXY, RADIO GALAXY RA=14H 15M 58.8167S +/- 0.1", J2000 V = 19 DEC=13D 20' 23.708" +/- 0.1" 8060( 3) - 07/16/98 16:36 - [ 5] Visit: 01 Visit Priority: Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 5 PKS1413+135 NIC1 ACCUM NIC1-FI BLANK NREAD=9 2 5.631 S POS TARG 1, 1 X Comments: NIC1 image persistance removal observation. ------------------------------------------------------------------------------------------------------------------------------------ 10 PKS1413+135 NIC1 MULTIAC NIC1-FI F160W SAMP-SEQ=STEP256,NSAMP=15 1 DEF POS TARG 1, 1 PAR 15, 16 CUM X WITH 10 Comments: We are positioning the target at the geometrical center of NIC1 in order to ensure acquisition of the galaxy's nucleus (the position we are using is from VLBI observations, which have slight (1") reference frame inconsistencies with the DSS). In order to eliminate effects from the bad rows, grot, warm pixels and other image defects, we will be doing a fourfold dither to positions (1, 1), (-1,-1), (1,-1) and (-1, 1) arcseconds from the NIC1-FIX aperture. ------------------------------------------------------------------------------------------------------------------------------------ 15 ANY NIC2 ACCUM NIC2 F110W NREAD=1 1 1260.58 Comments: Turn off C2 Autoflush to eliminate "bars" ------------------------------------------------------------------------------------------------------------------------------------ 16 ANY NIC3 ACCUM NIC3 F110W NREAD=1 1 1260.58 Comments: Turn off C3 Autoflush to eliminate "bars" ------------------------------------------------------------------------------------------------------------------------------------ 20 PKS1413+135 NIC1 MULTIAC NIC1-FI F160W SAMP-SEQ=STEP256,NSAMP=15 1 DEF POS TARG -1,-1 PAR 25, 26 CUM X WITH 20 Comments: We are positioning the target at the geometrical center of NIC1 in order to ensure acquisition of the galaxy's nucleus (the position we are using is from VLBI observations, which have slight (1") reference frame inconsistencies with the DSS). In order to eliminate effects from the bad rows, grot, warm pixels and other image defects, we will be doing a fourfold dither to positions (1, 1), (-1,-1), (1,-1) and (-1, 1) arcseconds from the NIC1-FIX aperture. ------------------------------------------------------------------------------------------------------------------------------------ 25 ANY NIC2 ACCUM NIC2 F110W NREAD=1 1 1260.58 Comments: Turn off C2 Autoflush to eliminate "bars" ------------------------------------------------------------------------------------------------------------------------------------ 26 ANY NIC3 ACCUM NIC3 F110W NREAD=1 1 1260.58 Comments: Turn off C3 Autoflush to eliminate "bars" ------------------------------------------------------------------------------------------------------------------------------------ 8060( 3) - 07/16/98 16:36 - [ 6] Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 30 PKS1413+135 NIC1 MULTIAC NIC1-FI F160W SAMP-SEQ=STEP256,NSAMP=15 1 DEF POS TARG 1,-1 PAR 35-36 CUM X WITH 30 Comments: We are positioning the target at the geometrical center of NIC1 in order to ensure acquisition of the galaxy's nucleus (the position we are using is from VLBI observations, which have slight (1") reference frame inconsistencies with the DSS). In order to eliminate effects from the bad rows, grot, warm pixels and other image defects, we will be doing a fourfold dither to positions (1, 1), (-1,-1), (1,-1) and (-1, 1) arcseconds from the NIC1-FIX aperture. ------------------------------------------------------------------------------------------------------------------------------------ 35 ANY NIC2 ACCUM NIC2 F160W NREAD=1 1 1260.58 Comments: Turn off C2 Autoflush to eliminate "bars" ------------------------------------------------------------------------------------------------------------------------------------ 36 ANY NIC3 ACCUM NIC3 F160W NREAD=1 1 1260.58 Comments: Turn off C3 Autoflush to eliminate "bars" ------------------------------------------------------------------------------------------------------------------------------------ 40 PKS1413+135 NIC1 MULTIAC NIC1-FI F160W SAMP-SEQ=STEP256,NSAMP=15 1 DEF POS TARG -1, 1 PAR 45-46 CUM X WITH 40 Comments: We are positioning the target at the geometrical center of NIC1 in order to ensure acquisition of the galaxy's nucleus (the position we are using is from VLBI observations, which have slight (1") reference frame inconsistencies with the DSS). In order to eliminate effects from the bad rows, grot, warm pixels and other image defects, we will be doing a fourfold dither to positions (1, 1), (-1,-1), (1,-1) and (-1, 1) arcseconds from the NIC1-FIX aperture. ------------------------------------------------------------------------------------------------------------------------------------ 45 ANY NIC2 ACCUM NIC2 F160W NREAD=1 1 1260.58 Comments: Turn off C2 Autoflush to eliminate "bars" ------------------------------------------------------------------------------------------------------------------------------------ 46 ANY NIC3 ACCUM NIC3 F160W NREAD=1 1 1260.58 Comments: Turn off C3 Autoflush to eliminate "bars" ------------------------------------------------------------------------------------------------------------------------------------ 8060( 3) - 07/16/98 16:36 - [ 7] Summary Form for Proposal 8060 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures NIC1-FIX NIC2 NIC3 ------------------------------------------------------------------------------------------------------------------------------------ Configurations NIC1 NIC2 NIC3 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NREAD=9 NSAMP=15 NREAD=1 SAMP-SEQ=STEP256 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO/DD ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements POS TARG 1, 1 POS TARG 1, 1 PAR 15, 16 WITH 10 POS TARG -1,-1 PAR 25, 26 WITH 20 POS TARG 1,-1 PAR 35-36 WITH 30 POS TARG -1, 1 PAR 45-46 WITH 40 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements BLANK F160W F110W ------------------------------------------------------------------------------------------------------------------------------------ Target Names PKS1413+135 ANY ------------------------------------------------------------------------------------------------------------------------------------