6057( 10) - 01/17/97 11:38 - [ 0] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6057 Version: 10 Check-in Date: 17-Jan-1997 11:34:44 1.Proposal Title: Ultra-High Resolution Studies of AGNs II:, 3C279 Proper Motion ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle AGN GO 5 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: ETHAN SCHREIER SPACE TELESCOPE SCIENCE INSTITUTE CoI: George Miley Sterrewacht Leiden, Leiden University N ------------------------------------------------------------------------------------ 6. Abstract A Cycle 1 pilot programme using the FGS to achieve ultra-high spatial resolution has been successful. We wish to follow up this work, studying the morphologies of AGNs on scales of tens of milliarcseconds. Several exciting problems concerning AGNs and their jets can be tackled uniquely by such observations -- the relation of optical continuum in AGNs to synchrotron jets, the detection of superluminal jet expansion in the optical, and spatially resolving the broad-line region. We have observed 3C279 with the FGS and found it to have optical structure on the scale of 40 milliarcseconds with additional components about 0.1 arcsec away along the position angle of the jet; hints of extent have also been seen in WFPC2 observations. We wish to study this structure in more detail and, in particular, search for optical superluminal motion, already known to exist in the radio. We will do this by repeating the FGS observations of 3C279 to look for time variable phenomena, by scanning in different directions to better study the small-scale spatial morphology, and by using the FOC to study the detailed morphology of the central region on the "larger" scales of 50-100 milliarcseconds, also using this latter data as a model for our FGS fitting. Our observations will provide information about nuclear structure on a scale of a few parsecs, measure the luminosity of a point-like component, and constrain the properties of a possible black hole. ------------------------------------------------------------------------------------ Observations Description ------------------------ As a result of our previous FGS observations, we know that the pupil mode provides the highest signal-to-noise, given the spherical aberration. The FGS with pupil is also being calibrated regularly. We thus propose to make only pupil observations. It is essential to do scans at different orientations, to characterize the morphology and demonstrate that the asymmetries which we have detected are real and not due to instrumental effects. Although the FGS gives simultaneous readouts along orthogonal axes, repeating the scans at different angles will allow us to simultaneously increase signal-to-noise, remove axis- dependent systematic effects, and most important, provide information about source structure with other projections. It is better to carry out all the scans closely in time, to avoid time-dependent calibration uncertainties. 3C279 is very close to the ecliptic, allowing multiple orientations near the anti- solar point. Following the recommended procedure, each "scan" will actually be constructed of a set of repeated individual scans to allow for elimination of data during which there is spacecraft jitter. The orientations chosen are 5D (45 deg from the jet position angle of 50 deg, so that one interferometer axis is along the jet and one is perpendicular to it), 35D, and 65D, providing interferometer scans at six independent angles through the source. Note that the initial discovery observations were with an ORIENT along the position angle of the jet; the interferometer axes were thus at 45 deg to the jet. The requested FOC observations of 3C279 are 2-color images, one using a broadband V filter to approximately match the FGS sensitivity, and one using a U filter, with a total exposure time of 2 orbits. The intensity of the source in Fall 1994 was well-suited to the FOC in the selected colors. However, because 3C279 has also been seen ~2 magnitudes brighter, we request to first use one orbit with the time split between the two filters, and to HOLD the repeat orbit, in case a neutral density filter is appropriate to avoid saturation. If the ND filter is not necessary for the second observation, we may also be able to observe time variability. Real Time Justification ----------------------- None. Calibration Justification ------------------------- Since a TRANS mode observation of a calibration target is used as the PSF in modeling the source, it is best if the FGS were calibrated not too long before or after these observations. Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: , ------------------------------------------------------------------------------------ 6057( 10) - 01/17/97 11:38 - [ 1] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 3C279 GALAXY, Quasar, RADIO RA = 12H 56M 11.15S +/- 1.", DEC J2000 Z = .538 V = 17. GALAXY, JET = -5D 47' 21.6" +/- 1.", PLATE- ID = 024R Comments: flux is variable by +/-~1m 6057( 10) - 01/17/97 11:38 - [ 2] Visit: 01 Visit Requirements: On Hold Comments: Additional Comments: First visit assumes lower range of mag Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 3C279 FOC/96 IMAGE 512X512 F550M 5460 1 16 M ------------------------------------------------------------------------------------------------------------------------------------ 2 3C279 FOC/96 IMAGE 512X512 F253M 2550 1 16 M ------------------------------------------------------------------------------------------------------------------------------------ 6057( 10) - 01/17/97 11:38 - [ 3] Visit: 02 Visit Requirements: On Hold Comments: Additional Comments: FOC Visit 2 may need ND if mag high on first visit Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 3C279 FOC/96 IMAGE 512X512 F550M, 5460 1 16 M F2ND ------------------------------------------------------------------------------------------------------------------------------------ 2 3C279 FOC/96 IMAGE 512X512 F253M, 2550 1 16 M F2ND ------------------------------------------------------------------------------------------------------------------------------------ 6057( 10) - 01/17/97 11:38 - [ 4] Visit: 03 Visit Requirements: ORIENT 93D TO 97D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 3C279 FGS TRANS 3 PUPIL 1 STEP-SIZE=0.6,SCANS=30 1 30.5 M ------------------------------------------------------------------------------------------------------------------------------------ 6057( 10) - 01/17/97 11:38 - [ 5] Visit: 04 Visit Requirements: ORIENT 123D TO 127D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 3C279 FGS TRANS 3 PUPIL 1 STEP-SIZE=0.6,SCANS=30 1 30.5 M ------------------------------------------------------------------------------------------------------------------------------------ 6057( 10) - 01/17/97 11:38 - [ 6] Visit: 05 Visit Requirements: ORIENT 153D TO 157D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 3C279 FGS TRANS 3 PUPIL 1 STEP-SIZE=0.6,SCANS=30 1 30.5 M ------------------------------------------------------------------------------------------------------------------------------------ 6057( 10) - 01/17/97 11:38 - [ 7] Summary Form for Proposal 6057 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOC/96 FGS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE TRANS ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters STEP-SIZE=0.6 SCANS=30 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category AGN ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 93D TO 97D ORIENT 123D TO 127D ORIENT 153D TO 157D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F550M F253M F550M,F2ND F253M,F2ND PUPIL ------------------------------------------------------------------------------------------------------------------------------------ Target Names 3C279 ------------------------------------------------------------------------------------------------------------------------------------