Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 3573c Report Date: 09-May-96:18:42 Version: ********** Check-in Date: ********** 1.Proposal Title: GEOMETRY AND GENERALIZABILITY OF THE REFLECTED LIGHT MODEL FOR SEYFERT 2 GALAXIES ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID QUASARS & AGN GO Sub Category SEYFERTS ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Ross D Cohen UNIVERSITY OF CALIFORNIA, SA USA 619-534-2664 ------------------------------------------------------------------------------------ 7. Abstract The polarized flux spectra of a few Seyfert 2 galaxies look like the flux spectra of Seyfert 1 nuclei, and the polarization position angles are perpendicular to the radio structure axes. This and other evidence suggests that all Seyfert 2 galaxies may have Seyfert 1 spectra visible only in reflected light. The broad-line regions can be viewed directly in the cases where the otherwise obscuring tori are viewed pole on, and such objects would be classified as Seyfert 1 galaxies. It is crucial to determine whether this generalization of the polarization results is correct, and in particular whether all Seyfert 2 galaxies have polarized nuclear continuua with position angles perpendicular to the radio source axes. We argue that contamination by host-galaxy starlight usually renders this virtually impossible to determine from the ground, while from space, the observations would be easy and straightforward. We can use the FOS on the HST as a polarimeter, cutting down drastically on the starlight by observing in the UV where the stellar flux is weak. We can also determine the geometry of the obscuring regions, and for about half of the objects, we can determine whether the mechanism of the polarization is dust or electron scattering. We can determine continuum slopes and identify broad Fe II features from the flux spectra we receive as a by-product of the polarimetry. ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 7.00 par: 0 10. Num targs pri: 7 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: FOS ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 3573c PI: Ross D Cohen Proposal Title: GEOMETRY AND GENERALIZABILITY OF THE REFLECTED LIGHT MODEL FOR SEYFERT 2 GALAXIES ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Pi Ross D Cohen UNIVERSITY OF CALIFORNIA, SAN USA DIEGO Robert Rj Antonucci UNIVERSITY OF CALIFORNIA, SANTA USA BARBARA Laura E Kay BARNARD COLLEGE USA Julian H Krolik THE JOHNS HOPKINS UNIVERSITY USA ------------------------------------------------------------------------------------ 3. Description of proposed observations. We will do broad--band polarimetry of 7 Seyfert 2 galaxies using the FOS, large aperture, Blue detector, the G270H grating, and B Waveplate. We will obtain a S/N of 4 in the polarized flux by binning the spectrum between about 2100A and 3000A, assuming that P = 3%. The polarization measurement will use 4 waveplate settings, to minimize overhead. Exposure times for four objects with known UV flux levels will be observed for 1200s, the other three for 1445s. Target acquisition will be by blind offset, after doing a binary search target acquisition on a nearby star (in the guide star catalog) which has a known offset from the Seyfert nucleus. The SNR of 4 in the polarized flux will produce a PA accurate to 7D, allowing us to determine unambiguously whether P is large or small and whether the PA are aligned (like Seyfert 1 galaxies and quasars) or perpendicular to the radio structure axis. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. The number of Seyfert 2 galaxies for which continuum polarization may be determined from ground--based observations is strictly limited to the nearest objects and those with the strongest continuum polarizations. This technique has been pushed to its limits by one of us (L. K.). Thus, it is not known whether the finding of Miller and collaborators that a few Seyfert 2 galaxies show a reflected Type 1 spectrum applies to only a subset of Seyfert 2s or to all of them. Our sample will yield an unbiased, unambiguous result for a large enough sample to settle the question of whether Seyfert 2 galaxies have an occulted source of non--stellar continuum. For the majority of Seyfert 2 galaxies, continuum polarization is impossible to determine from the ground due to contamination by polarized starlight, regardless of S/N. No space--based polarimeter capable of making these measurements exists other than on the HST. The unique ability of the HST to perform ultraviolet polarimetry will enable us to resolve this important question. Page 3 ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. The investigators have worked for the FOS IDT and have extensive experience both with the FOS and astronomical polarimetry. We will analyze the data at UCSD and UCSB. Processing is basically the same as for FOS spectral data. It is additionally necessary to add and difference the spectra taken at the different waveplate position angles to create the unnormalized Q and U polarized flux spectra, which are then divided by the modulation efficiency curve and added in quadrature to produce the total polarized flux. (The Q and U spectra will be binned to increase the S/N.) SDAS and IRAF will provide most or all of the necessary routines, along with a package of polarimetry routines written for VISTA, an image and spectral reduction/analysis package developed at the University of California. We expect that we can produce P and $\Theta$ almost immediately for each object which is observed. For those which are polarized and which do not have adequate radio maps, we will undertake to make appropriate maps. Improved maps can be acquired by using the VLA at 2~cm or 3.6cm (with the sensitive ``Voyager'' receivers). Results for the data will be published prior to making these new maps as the P measurements alone yield a valid scientific result. The distribution of P will be used to construct new models of the obscuring region. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. Typical sky survey images are burned out in the cores of these bright objects, hence the accurate coordinates necessary for FOS target acquisition must be acquired other than from the guide star plates. This has been done. As required, polarimetry of nearby stars to refine measurements of galactic interstellar polarization can be acquired as necessary at Lick Observatory. New radio maps may be made as a follow--up. Their acquisition will not delay the output of our polarimetry results. ------------------------------------------------------------------------------------ 9. Description of previous HST work. Antonucci and Cohen have worked on FOS--Team GTO data, but are not Co-- investigators. Antonucci expects to receive CYCLE 1 GO data. The only data received so far are GTO data, some of which (on NGC 1068: see below) are related to this proposal. We are working on a broad range of AGN and Quasar data taken by the FOS IDT with H. Ford or M. Burbidge as P.I. Antonucci has worked on NGC 1068 emission line imaging and nuclear spectrophotometry in which much has been learned about the occultation/reflection model for this prototype, eg that we can pinpoint the obscured nucleus at the emission line cone apex, and that it is located at the megamaser position. We are now using VLBI velocity field observations of the maser in an attempt to detect dynamically and to weigh the putative supermassive black hole. The small--aperture spectrophotometry and the imaging have provided evidence that the mirror is spatially extended, verifying a theoretical prediction by Miller, Mathews, and Goodrich (Ap. J., in press). ``FOS Spectroscopy of Resolved Structure in the Nucleus of NGC 1068'', S. Caganoff, R.R.J. Antonucci, H.C. Ford, G.A. Kriss, G. Hartig, L. Armus, I.N. Evans, E. Rosenblatt, R.C. Bohlin and A.L. Kinney, Ap. J. Lett., in press, 1991. ``HST Line Imaging of the Inner 3 Arcseconds NGC 1068 in the Light of [O III]lambda5007'', I. Evans, H. Ford, A. Kinney, R. Antonucci, S. Caganoff and L. Armus, Ap. J. Lett. 369, L27, 1991). ``Far UV Spectroscopy of the QSO UM 675 with the FOS and the HST'', E. Beaver, E. Burbidge, R. Cohen, V. Junkkarinen, R. Lyons, E. Rosenblatt, G. Hartig, B. Margon, and A. Davidsen, Ap. J. Lett. in press, 1991. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). All computing facilities required for data reduction and analysis and any theoretical follow--up already exist at our institutions. Any necessary supporting optical polarimetric observations will be done at University of California facilities. Page 4 ------------------------------------------------------------------------------------ 11. Address Information Name: ROSS D COHEN Category: PI Institution: UNIVERSITY OF CALIFORNIA, SAN DIE Address: CASS 0111, UCSD 9500 GILMAN DRIVE City: SAN DIEGO State: CA Zip Code: 920930111 Country: USA Telephone: 619 534 2664 Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 3573c [ 5] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial |Acqui|FLX| Flux data No | Name | Description | Position |Eqnx | Vel. |Prblm|REF| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 1 MRK3 E,312,923,924 RA-OFF = 3.60S +/- 0.02S, 2000 Z=.014 1 V = 13.3 +/- .5 DEC-OFF = -1' 15.71" +/- 2 F-CONT(2500) = 2.6 +/- 1.0 E-15 0.1", FROM 11, PLATE-ID=00M8 Comments: IN THE NEXT FEW MONTHS, WE WILL BE ABLE TO EXAMINE FOS TEAM IMAGES OF THIS OBJECT. THESE MAY LEAD TO CHANGES IN THE OFFSET AND/OR OFFSET STARS. ------------------------------------------------------------------------------------------------------------------------------------ 2 MRK477 E,312,923,924 RA-OFF = -4.249S +/- 0.011S, 2000 Z = .038 1 V = 15.0 +/- .5 DEC-OFF = -16.78" +/- 0.1", 2 F-CONT(2500) = 3.1 +/- 1.0 E-15 FROM 12, PLATE-ID=01AL Comments: IN THE NEXT FEW MONTHS, WE WILL BE ABLE TO EXAMINE FOS TEAM IMAGES OF THIS OBJECT. THESE MAY LEAD TO CHANGES IN THE OFFSET AND/OR OFFSET STARS. ------------------------------------------------------------------------------------------------------------------------------------ 3 MRK1066 E,312,923,924 RA-OFF = 11.90S +/- 0.008S, 2000 Z = .012 1 V = 14.0 +/- .5 DEC-OFF = 31.91" +/- 0.1", 2 F-CONT(2500) = 2.3 +/- 2.3 E-15 FROM 13, PLATE-ID=036R ------------------------------------------------------------------------------------------------------------------------------------ 4 NGC4388 E,312,923,924 RA-OFF = -2.13S +/- 0.007S, 2000 Z = .008 1 V = 13.9 +/- .5 DEC-OFF = +2' 54.05" +/- 2 F-CONT(2500) = 4.1 +/- 2.0 E-15 0.1", FROM 14, PLATE-ID=00IY ------------------------------------------------------------------------------------------------------------------------------------ 5 MRK1073 E,312,923,924 RA-OFF = 5.48S +/- 0.009S, 2000 Z = .023 1 V = 14.2 +/- .5 DEC-OFF = 1' 24.14" +/- 2 F-CONT(2500) = 1.3 +/- 1.3 E-15 0.1", FROM 15, PLATE-ID=02RZ ------------------------------------------------------------------------------------------------------------------------------------ 6 MRK463E E,312,923,924 RA = 13H 56M 2.920S +/- 2000 Z = .051 1 V = 14.2 +/- .5 0.3", 2 F-CONT(2500) = 2.0 +/- 1.5 E-15 DEC = 18D 22' 18.83" +/- 0.3", PLATE-ID=019M Comments: IN THE NEXT FEW MONTHS, WE WILL BE ABLE TO EXAMINE FOS TEAM IMAGES OF THIS OBJECT. THESE MAY LEAD TO CHANGES IN THE OFFSET AND/OR OFFSET STARS. ------------------------------------------------------------------------------------------------------------------------------------ 8 MRK1 E,312,923,924 RA-OFF = 8.10S +/- 0.008S, 2000 Z = .016 1 V = 15.0 +/- .5 DEC-OFF = -21.18" +/- 0.1", 2 F-CONT(2500) = 1.1 +/- 1.1 E-15 FROM 18, PLATE-ID=00DV ------------------------------------------------------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 3573c [ 6] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial |Acqui|FLX| Flux data No | Name | Description | Position |Eqnx | Vel. |Prblm|REF| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 11 MRK3-OFFSET A,137 RA = 06H 15M 32.695S +/- 2000 1 V = 12.23 +/- 0.04, TYPE=G6-G8V GSC4349-884 0.3", DEC = +71D 03' 31.02" +/- 0.3", PLATE-ID=00M8 ------------------------------------------------------------------------------------------------------------------------------------ 12 MRK477- A,137 RA = 14H 40M 42.309S +/- 2000 1 V = 12.26 +/- 0.01, TYPE=G6-G8V OFFSET 0.3", GSC3860-523 DEC = 53D 30M 32.51" +/- 0.3", PLATE-ID=01AL ------------------------------------------------------------------------------------------------------------------------------------ 13 MRK1066- A,137 RA = 02H 59M 46.711S +/- 2000 1 V = 12.40 +/- 0.13, TYPE=G6-G8V OFFSET 0.3", GSC2338-890 DEC = 36D 48' 42.19" +/- 0.3", PLATE-ID=036R ------------------------------------------------------------------------------------------------------------------------------------ 14 NGC4388- A,137 RA = 12H 25M 48.859S +/- 2000 1 V = 11.68 +/- 0.48, TYPE=K3-K4V OFFSET 0.3", GSC880-517 DEC = +12D 36' 46.920" +/- 0.3", PLATE-ID=00IY ------------------------------------------------------------------------------------------------------------------------------------ 15 MRK1073- A,137 RA = 03H 14M 55.920S +/- 2000 1 V = 11.04 +/- 0.22, TYPE=K4-K5V OFFSET 0.3", GSC2856-2121 DEC = 42D 00' 45.28" +/- 0.3", PLATE-ID=02RZ ------------------------------------------------------------------------------------------------------------------------------------ 16 MRK463E- A,137 RA = 13H 56M 1.854S +/- 2000 1 V = 12.48 +/- 0.26, TYPE=G2V OFFSET 0.3", GSC1470-633 DEC = 18D 23' 27.52" +/- 0.3", PLATE-ID=019M ------------------------------------------------------------------------------------------------------------------------------------ 18 MRK1-OFFSET A,137 RA = 01H 15M 59.182S +/- 2000 1 V = 14.06 +/- 0.18, TYPE=A3-A4V GSC2295-1251 0.3", DEC = 33D 5' 42.86" +/- 0.3", PLATE-ID=00DV ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 3573c [ 7] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 MRK3-OFFSET FOS/BL ACQ/ 4.3 MIRROR BRIGHT=720000 1 2.56S 1 2 ONBOARD ACQ FOR 2 BINARY SEQ 1-2 NO GAP CYCLE 2 / 1-16 REQ UPDATE ------------------------------------------------------------------------------------------------------------------------------------ 2 MRK3 FOS/BL ACCUM 4.3 G270H POLSCAN=4B 1 1200S 2 2 REQ UPDATE ------------------------------------------------------------------------------------------------------------------------------------ 3 MRK477- FOS/BL ACQ/ 4.3 MIRROR BRIGHT=720000 1 2.63S 1 1 ONBOARD ACQ FOR 4 OFFSET BINARY SEQ 3-4 NO GAP REQ UPDATE ------------------------------------------------------------------------------------------------------------------------------------ 4 MRK477 FOS/BL ACCUM 4.3 G270H POLSCAN=4B 1 1200S 2 1 REQ UPDATE ------------------------------------------------------------------------------------------------------------------------------------ 5 MRK1066- FOS/BL ACQ/ 4.3 MIRROR BRIGHT=720000 1 3.00S 1 3 ONBOARD ACQ FOR 6 OFFSET BINARY SEQ 5-6 NO GAP ------------------------------------------------------------------------------------------------------------------------------------ 6 MRK1066 FOS/BL ACCUM 4.3 G270H POLSCAN=4B 1 1445S 2 3 ------------------------------------------------------------------------------------------------------------------------------------ 7 NGC4388- FOS/BL ACQ/ 4.3 MIRROR BRIGHT=720000 1 2.96S 1 3 ONBOARD ACQ FOR 8 OFFSET BINARY SEQ 7-8 NO GAP ------------------------------------------------------------------------------------------------------------------------------------ 8 NGC4388 FOS/BL ACCUM 4.3 G270H POLSCAN=4B 1 1200S 2 3 ------------------------------------------------------------------------------------------------------------------------------------ 9 MRK1073- FOS/BL ACQ/ 4.3 MIRROR BRIGHT=720000 1 1.84S 1 2 ONBOARD ACQ FOR 10 OFFSET BINARY SEQ 9-10 NO GAP ------------------------------------------------------------------------------------------------------------------------------------ 10 MRK1073 FOS/BL ACCUM 4.3 G270H POLSCAN=4B 1 1445S 2 2 ------------------------------------------------------------------------------------------------------------------------------------ 11 MRK463E- FOS/BL ACQ/ 4.3 MIRROR BRIGHT=720000 1 2.71S 1 4 ONBOARD ACQ FOR 12 OFFSET BINARY SEQ 11-12 NO GAP REQ UPDATE ------------------------------------------------------------------------------------------------------------------------------------ 12 MRK463E FOS/BL ACCUM 4.3 G270H POLSCAN=4B 1 1200S 2 4 REQ UPDATE ------------------------------------------------------------------------------------------------------------------------------------ 15 MRK1-OFFSET FOS/BL ACQ/ 4.3 MIRROR BRIGHT=720000 1 5.53S 1 1 ONBOARD ACQ FOR 16 BINARY SEQ 15-16 NO GAP ------------------------------------------------------------------------------------------------------------------------------------ 16 MRK1 FOS/BL ACCUM 4.3 G270H POLSCAN=4B 1 1445S 2 1 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 3573c [ 8] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOS/BL ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/BINARY ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BRIGHT POLSCAN ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 7.00 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category QUASARS & AGN ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category SEYFERTS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 2; SEQ 1-2 NO GAP; CYCLE 2 / 1-16; REQ UPDATE; ONBOARD ACQ FOR 4; SEQ 3-4 NO GAP; ONBOARD ACQ FOR 6; SEQ 5-6 NO GAP ONBOARD ACQ FOR 8; SEQ 7-8 NO GAP ONBOARD ACQ FOR 10; SEQ 9-10 NO GAP ONBOARD ACQ FOR 12; SEQ 11-12 NO GAP; ONBOARD ACQ FOR 16; SEQ 15-16 NO GAP ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G270H ------------------------------------------------------------------------------------------------------------------------------------ Target Names MRK3 MRK477 MRK1066 NGC4388 MRK1073 MRK463E MRK1 MRK3-OFFSET GSC4349-884 MRK477-OFFSET GSC3860-523 MRK1066-OFFSET GSC2338-890 NGC4388-OFFSET GSC880-517 MRK1073-OFFSET GSC2856-2121 MRK463E-OFFSET GSC1470-633 MRK1-OFFSET GSC2295-1251 ------------------------------------------------------------------------------------------------------------------------------------