Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 5426 Report Date: 18-Jul-95:17:21 Version: ********** Check-in Date: ********** 1.Proposal Title: COLLIMATED RADIO AND IONIZING RADIATION IN NGC 5252 ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID GALAXIES GO Sub Category SEYFERT ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Zlatan I Tsvetanov JOHNS HOPKINS UNIVERSITY USA 410-516-8585 ------------------------------------------------------------------------------------ 7. Abstract Ground-based emission-line images of the Seyfert 2 galaxy NGC5252 reveal perhaps the most spectacular ionization cone known. The bi-conical structure extends to large distances from the nucleus and is significantly misaligned w.r.t. the major axis of the host galaxy. Our VLA radio maps show a clear nuclear jet, which is coaligned with the ionization cone axis to within the measurement errors. In addition, ground- based long-slit spectra and our Fabry-Perot imagessuggest possible helical motions. We propose to obtain narrow-band WFPC2 images in the OIII 5007, Halpha and OII 3727 and 2 continuum bands. These will be used to map the ionizing radiation field all the way in to the nucleus and study the correlation between the radio and optical emission on sub-arcsecond scales. We will also use the line ratio maps to try to put constraints on the angular dependence of the ionizing field as well as continuum color maps to look for the presence of local ionizing sources such as hot stars in addition to the hard nuclear radiation. ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 3.50 par: 0 10. Num targs pri: 1 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: WF/PC ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 5426 PI: Zlatan I Tsvetanov Proposal Title: COLLIMATED RADIO AND IONIZING RADIATION IN NGC 5252 ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Zlatan I Tsvetanov 2380 USA Andrew S Wilson 3470 USA Jon Morse 3470 USA ------------------------------------------------------------------------------------ 3. Description of proposed observations. NGC5252 will be imaged in two continuum and three emission lines bands. (1) The [OIII]5007 image. In a future proposal, we will use the ramp filter FR533N. This will provide us with a 0.1 "/px resolution image which than can be compared with our radio VLA map of the same resolution. This will be a 5x--10x improvement compared with the best available ground-based images. (2) The H-alpha image. Because of the redshift of NGC 5252, cz=6925, km s-1, the H-alpha+[NII] complex of lines falls into the passband of F673N. We will take a PC image through this filter to achieve the highest possible resolution of 0.046 "/px. (3) The [OII]3727 image. The redshited position of this line (lambda=3813 A) falls into the passband of one of the quadrand filters - FQUVN-B. This image will be ratioed with the [OIII]5007 image to construct a line-ratio map sensitive to the ionisation parameter U. (4) Continuum images. We plan to take 2 continuum images - one in the wavelength range between [OIII]5007 and H-alpha and one next to [OII]3727. Unfortunately, because of the redshift of NGC5252 we can not use F547M - the 5007 line is in the bandpass. Instead, we will use F588N, which has a bandwith of only approx.50 A, but because of the higher system troughput does not increase unreasonably the exposure time. For the UV continuum image we will use F336W. Our estimates of the exposure time are based on the following formula and assumptions (see WFPC2 Handbook for more details): N(el) = 2.3e12 t(exp) QT(max) lambda F(line) where N(el) is the number of electrons detected, t(exp) is the exposure time in seconds, lambda is the wavelength in A, and F(line) is the observed integrated line flux in ergs cm-2 s-1. These e- will be spread over the area covered by the resolved emission-line structure. Exposure time estimates through each of the proposed filters are based on the fluxes measured from our calibrated ground-based images. From our [oiii]5007 image we measure approx. 1.5e -13 ergs cm-2 s-1 in the central 2". This leads to roughly 12000 counts in a 20 min exposure distributed over the area covered by the emission-line structure (maximum of 400 WFC 0.1" pixels). Therefore, there will be no numerical saturation in the low read-out-noise mode (7 e- RON) even if all of the emission is concentrated in one or few point-like sources. Estimates for the exposure times in [oii]3727 line and two continuum bands are based on a ground-based long- slit spectrum obtained at with the 3.6m telescope at ESO. These estimates assume that the velocity dispersion in the extended regions is not larger than +/- 300- 350 km s-1 around the systemic velocity (as suggested by our Fabry-Perot data), so the line remains within the filter bandpass. Estimated exposure times are as follows: F336W (UV cont.) - 50 min, FQUVN-B ([oii]3727) - 50 min, FR533N ([oiii]5007) - 40 min, F588N (cont.) - 40 min, F673N (H-alpha) - 30 min. Note - Each exposure will be taken in CR split mode. Page 3 ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. NGC5252 offers one of the best laboratories to study many important questions related to the collimated nuclear emission and radio jet -- host galaxy interaction. For this one needs to obtain optical images with resolution approximately matching that of the VLA radio map. This is possible only with the HST. Prior to this proposal we have obtained ground-based emission-line and Fabry -Perot images, as well as VLA radio maps. All these have been used in planing the HST observations. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. We have no special requests. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. We have no special calibration requirements. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. ------------------------------------------------------------------------------------ 9. Description of previous HST work. 1036: Imaging and Spectrophotometry of Seyfert Nuclei (GTO/FOS 14) - Ford (PI) plus the FOS team. 3671: UV Spectroscopy of Hydrogen-Poor Planetary Nebulae - Harrington (PI), Borkowski, Tsvetanov, Clegg. Not related to this proposal. 3724: Ionizing Cones, Obscuring Tori, and the Narrow line Regions of Seyfert Galaxies - Wilson (PI), Heckman, Bower. 4371: FOS Spectroscopy of Resolved Structure in the Nucleus of Mrk 3 - Tsvetanov (PI), Evans, Ford, Kriss, Uomoto, Davidsen. 4503: Absorption-Line spectra of Seyfert Galaxies - Kriss (PI), Ford, Tsvetanov, Davidsen. Completion of observations pending. 4668: FOS Spectroscopy of NGC1052 and NGC4258 - Ford (PI), Evans, Kriss, Kinney, Tsvetanov. Completion of observations pending. Analysis of the HST images and spectra taken as part of GTO 1036 has inspired some of the ideas presented here. In particular, we would like to mention Mrk 3, which shows signatures of possible jet -- local ISM interaction and NGC4151, where HST observations present a clear problem for the simplest version of the Unified Model of AGN. Imaging part of 1036 is completed and FOS observations continue being taken in cycle 3. From these observations we have identified (1) a general association between the radio and emission-line structures, (2) ionization cones, but with (presumably) obscured apices, and (3) very red continuum colors at the inferred position of the nucleus, possibly due to differential reddening. Several papers discussing ``unified models" for Seyfert galaxies are forthcoming. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). At the Center for Astrophysical Sciences, the Johns Hopkins University and at STScI, we have access to a network of Sun Workstations and the appropriate software (IRAS, STSDAS) is installed. The network maintenance and other supproting technical assistance is provided through group maintenance contracts for computer equipment. The university provides opportunities for graduate students as well as undergraduates to assist in research projects for academic credit. ------------------------------------------------------------------------------------ 11. Address Information Page 4 Name: Zlatan I TSVETANOV Category: PI Institution: 2380 Address: Center for Astrophysical Sciences Department of Physics and Astronomy 34th & North Charles Street City: Baltimore State: MD Zip Code: 21218 Country: USA Telephone: 410-516-8585 Telex (or e-mail): zlatan@pha.jhu.edu ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 5426 [ 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 NGC5252 E,312,910,924 RA = 13H 38M 15.867S +/- 2000 V = 6890 1 B=14.11 +/- 0.3 UGC8622 0.1", 1 F-LINE(5007)=1.5 +/- 0.05 E-13 DEC = +4D 32' 33.53" +/- 0.1", PLATE-ID=019P Comments: LINE FLUX IS 2" APERTURE MEASURED FROM GROUND-BASED IMAGES. ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 5426 [ 6] ------------------------------------------------------------------------------------------------------------------------------------ 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 NGC5252 WFPC2 IMAGE PC1 F336W 3344 CR- 1 1800S 1 1 CYCLE 4 / 1-1.4 TOLERANCE=0.0 1 ------------------------------------------------------------------------------------------------------------------------------------ 1.05 NGC5252 WFPC2 IMAGE PC1 F336W 3344 CR- 1 1700S 1 1 TOLERANCE=0.0 1 ------------------------------------------------------------------------------------------------------------------------------------ 1.1 NGC5252 WFPC2 IMAGE WF4 FQUVN 3813 CR- 1 1800S 1 TOLERANCE=0.0 ------------------------------------------------------------------------------------------------------------------------------------ 1.15 NGC5252 WFPC2 IMAGE WF4 FQUVN 3813 CR- 1 1700S 1 TOLERANCE=0.0 ------------------------------------------------------------------------------------------------------------------------------------ 1.3 NGC5252 WFPC2 IMAGE WF2 F588N 5893 CR- 1 2400S 1 TOLERANCE=0.0 ------------------------------------------------------------------------------------------------------------------------------------ 1.4 NGC5252 WFPC2 IMAGE PC1 F673N 6714 CR- 1 1800S 1 TOLERANCE=0.0 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 5426 [ 7] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-TOLERANCE=0.0 ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 3.50 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category GALAXIES ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category SEYFERT ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements CYCLE 4 / 1-1.4 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F336W FQUVN F588N F673N ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC5252 UGC8622 ------------------------------------------------------------------------------------------------------------------------------------