6214( 6) - 07/21/95 15:24 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6214 Version: 6 Check-in Date: ********** 1.Proposal Title: FOS SPECTROPOLARIMETRY OF OVV QUASARS ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle QUASARS GTO/FOS 5 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Dr. J.R.P. Angel Steward Observatory CoI: Dr. Arthur Davidsen Johns Hopkins University N CoI: Dr. Richard Harms Applied Research Corporation N CoI: Dr. Ralph Bohlin Space Telescope Science Institute N CoI: Dr. Paul Smith Steward Observatory Y CoI: Dr. Richard Allen Steward Observatory N CoI: Dr. Edward Beaver UC, San Diego N CoI: Dr. E. Margaret Burbidge UC, San Diego N CoI: Dr. Bruce Margon University of Washington N CoI: Dr. Holland Ford Johns Hopkins University N CoI: Dr. Frank Bartko Martin Marietta Corporation N ------------------------------------------------------------------------------------ 6. Abstract Several Optically Violent Variable (OVV) quasars show strong wavelength-dependent linear polarization at optical and near-IR wavelengths. The wavelength dependence is in the sense that the polarization increases with wavelength. This behavior, which is quite different from that exhibited by the other type of synchrotron- dominated AGN, the BL Lac objects, has been explained by the presence of a blue, low -polarization continuum component that dilutes the synchrotron polarization of the OVV. It has been proposed that this unpolarized continuum component is "normal" quasar light and that these objects would be low- polarization, optically selected quasars if we were not located in the line-of-sight of the relativistically-beamed synchrotron jet. This program is designed to extend the study of the polarization properties of OVV quasars into the ultraviolet. Two of the brighter OVVs, 3C345 and 3C454.3, will be observed with the polarimeter of the FOS in order to measure the dilution caused by the blue continuum component in the UV. An attempt will be made to acquire simultaneous (or near-simultaneous) ground-based optical polarimetry of these variable objects to complement the UV measurements and characterize the wavelength-dependent polarization observed at longer wavelengths. In order to facilitate these ground-based observations, we request that the HST observations be made around new moon if possible (any time during the 2 weeks following a third quarter moon will allow accurate optical polarimetry of the targets). In addition, optical measurements can only be made when the targets are reasonably placed in the night sky. Therefore, please do not schedule the 3C345 observations between September 15 and February 1. Do not schedule the 3C454.3 observations between December 15 and June 1. ------------------------------------------------------------------------------------ 6214( 6) - 07/21/95 15:24 - [ 2] Observations Description ------------------------ We propose to obtain UV spectropolarimetry of two OVV quasars using the FOS. Observations will be made using the BLUE Digicon of the FOS, 1.0 aperture, and G190H, G270H, and G400H gratings. Polarimetry using G400H will be taken so that there is some spectral overlap between the HST observations and planned near-simultaneous optical polarimetry. As stated in the Abstract, we request that the HST observations be scheduled between third and first quarter moon. Optical, ground-based polarimetric signal-to- noise ratio is largely determined by the sky background. Therefore, avoiding a bright moon is essential for accurate optical polarimetry and will greatly increase the scientific yield of the invested HST time. Since both quasars are highly variable, an ACQ/PEAK will be used to acquire the targets. Because of the variable nature of these objects, all polarimetry must be acquired during 1 visit to each target. Short spectroscopic exposures of the targets using G570H will be made during the acquisition orbits in order to fully use the available visibility time during these orbits. Real Time Justification ----------------------- We do not require REAL-TIME observations. However, obtaining ground-based optical observations that would complement the HST UV data could be made if the HST measurements were scheduled when the moon is not too bright (+/- 1 week of the date of a new moon). Because the targets are variable, we intend to acquire near-simultaneous optical observations. These optical observations can be made only if the targets are reasonably placed in the night sky. The period between September 15 and February 1 should be avoided when scheduling the 3C345 HST observation. Likewise, please avoid December 15 to June 1 when scheduling 3C454.3. Calibration Justification ------------------------- Additional Comments ------------------- Ground-based optical polarimetry will be obtained simultaneously (hopefully within a day) with the HST polarimetry. If possible, schedule the HST observations within 1 week of a new moon (see above). In addition, it is necessary for the targets to be in the night sky so that ground-based measurements can be made. Therefore please avoid September 15 to February 1 when scheduling 3C345 and avoid December 15 to June 1 when scheduling 3C454.3. ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: , ------------------------------------------------------------------------------------ 6214( 6) - 07/21/95 15:24 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 3C345 GALAXY, Quasar RA = 16H 42M 58.78S +/- 0.05S, J2000 Z = V = 16.0 +/- 1.3 DEC = 39D 48' 37.0" +/- 0.4", 0.595 B-V = 0.3 PLATE-ID = 00CL E(B-V) = 0.00 Comments: Variable quasar (OVV) 2 3C454.3 GALAXY, Quasar RA = 22H 53M 57.77S +/- 0.05S, J2000 Z = V = 16.5 +/- 1.0 DEC = 16D 08' 53.3" +/- 0.4", 0.859 B-V = 0.47 PLATE-ID = 00GO E(B-V) = 0.065 Comments: Variable quasar (OVV) 6214( 6) - 07/21/95 15:24 - [ 4] Visit: 01 Visit Requirements: PERIOD 29.530589D AND ZERO-PHASE 14-MAY-95:20:48 On Hold Comments: Additional Comments: Please schedule the HST observation within 1 week of New Moon as a bright sky greatly compromises the planned optical ground based observations. ZERO -PHASE above represents full moon. Also, in order for ground based observations to be possible, the HST observation for 3C345 should be made before 15-SEP-95 or BETWEEN 1-FEB-96 AND 15-SEP-96 (i.e., ground-based observations are NOT possible between 15-SEP and 1-FEB). Optimal time for ground-based observations is MAY-JUN. The time critical specical requirements were not used because a visit cannot have both time and phase critical special requirements. Time criticality will be implmented manually by the program coordinator (Tony Roman). Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 100 3C345 FOS/BL ACQ/PEA 4.3 MIRROR SCAN-STEP- 1 2S ONBOARD ACQ FOR 101 K Y=1.23, SEARCH- SIZE-X=1, SEARCH-SIZE-Y=3 ------------------------------------------------------------------------------------------------------------------------------------ 101 3C345 FOS/BL ACQ/PEA 1.0 MIRROR SCAN-STEP- 1 2S ONBOARD ACQ FOR 102 K X=0.61, SCAN- STEP-Y=0.61, SEARCH-SIZE- X=6, SEARCH- Comments: SIZE-Y=2 ------------------------------------------------------------------------------------------------------------------------------------ 102 3C345 FOS/BL ACQ/PEA 0.3 MIRROR SCAN-STEP- 1 2.2S ONBOARD ACQ FOR 103-110 K X=0.17, SCAN- STEP-Y=0.17, SEARCH-SIZE- X=5, SEARCH- Comments: SIZE-Y=5 ------------------------------------------------------------------------------------------------------------------------------------ 103 3C345 FOS/BL ACCUM 1.0 G570H 5690 1 450S PHASE .27 TO .73 Comments: Phase represents new moon +/- ~7 days ------------------------------------------------------------------------------------------------------------------------------------ 104 3C345 FOS/BL ACCUM 1.0 G190H 1959 POLSCAN=8B 1 1860S ------------------------------------------------------------------------------------------------------------------------------------ 105 3C345 FOS/BL ACCUM 1.0 G270H 2750 POLSCAN=8B 1 1860S ------------------------------------------------------------------------------------------------------------------------------------ 106 3C345 FOS/BL ACCUM 1.0 G190H 1959 POLSCAN=8B 1 1860S ------------------------------------------------------------------------------------------------------------------------------------ 107 3C345 FOS/BL ACCUM 1.0 G400H 4008 POLSCAN=8A 1 1860S ------------------------------------------------------------------------------------------------------------------------------------ 108 3C345 FOS/BL ACCUM 1.0 G190H 1959 POLSCAN=8B 1 1860S ------------------------------------------------------------------------------------------------------------------------------------ 109 3C345 FOS/BL ACCUM 1.0 G270H 2750 POLSCAN=8B 1 1860S ------------------------------------------------------------------------------------------------------------------------------------ 110 3C345 FOS/BL ACCUM 1.0 G190H 1959 POLSCAN=8B 1 1860S ------------------------------------------------------------------------------------------------------------------------------------ 6214( 6) - 07/21/95 15:24 - [ 5] Visit: 02 Visit Requirements: PERIOD 29.530589D AND ZERO-PHASE 14-MAY-95:20:48 On Hold Comments: Additional Comments: Please schedule the HST observation within 1 week of New Moon as a bright sky greatly compromises the planned optical ground based observations. ZERO -PHASE above represents full moon. Also, in order for ground based observations to be possible, the HST observation for 3C454.3 should be made before BETWEEN 1-JUN-95 AND 15-DEC-95 or BETWEEN 1-JUN-96 AND 15-DEC-96 (i.e., ground-based observations are NOT possible between 15-DEC and 1-JUN). Optimal time for ground-based observations is SEP-OCT. The time critical specical requirements were not used because a visit cannot have both time and phase critical special requirements. Time criticality will be implmented manually by the program coordinator (Tony Roman). Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 200 3C454.3 FOS/BL ACQ/PEA 4.3 MIRROR SCAN-STEP- 1 2S ONBOARD ACQ FOR 201 K Y=1.23, SEARCH- SIZE-X=1, SEARCH-SIZE-Y=3 ------------------------------------------------------------------------------------------------------------------------------------ 201 3C454.3 FOS/BL ACQ/PEA 1.0 MIRROR SCAN-STEP- 1 2S ONBOARD ACQ FOR 202 K X=0.61, SCAN- STEP-Y=0.61, SEARCH-SIZE- X=6, SEARCH- Comments: SIZE-Y=2 ------------------------------------------------------------------------------------------------------------------------------------ 202 3C454.3 FOS/BL ACQ/PEA 0.3 MIRROR SCAN-STEP- 1 2.2S ONBOARD ACQ FOR 203-207 K X=0.17, SCAN- STEP-Y=0.17, SEARCH-SIZE- X=5, SEARCH- Comments: SIZE-Y=5 ------------------------------------------------------------------------------------------------------------------------------------ 203 3C454.3 FOS/BL ACCUM 1.0 G570H 5690 1 380S PHASE .27 TO .73 Comments: Phase represents new moon +/- ~7 days ------------------------------------------------------------------------------------------------------------------------------------ 204 3C454.3 FOS/BL ACCUM 1.0 G190H 1959 POLSCAN=4B 1 2020S ------------------------------------------------------------------------------------------------------------------------------------ 205 3C454.3 FOS/BL ACCUM 1.0 G270H 2750 POLSCAN=4B 1 2020S ------------------------------------------------------------------------------------------------------------------------------------ 206 3C454.3 FOS/BL ACCUM 1.0 G190H 1959 POLSCAN=4B 1 2020S ------------------------------------------------------------------------------------------------------------------------------------ 207 3C454.3 FOS/BL ACCUM 1.0 G400H 4008 POLSCAN=4A 1 2020S ------------------------------------------------------------------------------------------------------------------------------------ 6214( 6) - 07/21/95 15:24 - [ 6] Summary Form for Proposal 6214 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOS/BL ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/PEAK ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SCAN-STEP-Y=1.23 SEARCH-SIZE-X=1 SEARCH-SIZE-Y=3 SEARCH-SIZE-Y=2 SEARCH-SIZE-Y=5 POLSCAN=8B POLSCAN=8A SEARCH-SIZE-X=6 SEARCH-SIZE-X=5 POLSCAN=4B POLSCAN=4A ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GTO/FOS ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category QUASARS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PERIOD 29.530589D AND ZERO-PHASE 14-MAY-95 20 48 ONBOARD ACQ FOR 101 ONBOARD ACQ FOR 102 ONBOARD ACQ FOR 103-110 PHASE .27 TO .73 ONBOARD ACQ FOR 201 ONBOARD ACQ FOR 202 ONBOARD ACQ FOR 203-207 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G570H G190H G270H G400H ------------------------------------------------------------------------------------------------------------------------------------ Target Names 3C345 3C454.3 ------------------------------------------------------------------------------------------------------------------------------------