Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 1217c Report Date: 09-May-96:16:20 Version: ********** Check-in Date: ********** 1.Proposal Title: THE NUCLEUS OF NGC 1052 ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID QUASARS & AGN GTO/FOC Sub Category ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Alec Boksenberg ROYAL GREENWICH OBSERVATORY UNITED KIN 0223-374000 PROFESSOR ------------------------------------------------------------------------------------ 7. Abstract We show that the ST-FOC (in the first order of the long-slit spectrographic mode) allows to decide unambiguously which mechanism - photoionization by a central source or shock heating - is at work in this nucleus and thus to answer a fundamental question concerning active nuclei in general. In addition, the imaging mode of the FOC can provide the basic data with which to answer questions about the interaction between the nuclear activity and the interstellar medium. This is of relevance to ideas about the formation and maintenance of beams which power double radio sources. The question of stratification in nearby AGN is a general one, but we believe that NGC 1052 should be considered as a priority object because of the interest of the problems that can be solved in a reasonable observing time. ------------------------------------------------------------------------------------ 8. Scientific Key Words: GALAXIES : INDIVIDUAL - GALAXIES : NUCLEI - GALAXIES : LINERS - RADIATION MECHANISMS - RADIOGALAXY ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 2.50 par: 0 10. Num targs pri: 1 par: 0 ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 1217c PI: Alec Boksenberg Proposal Title: THE NUCLEUS OF NGC 1052 ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ David Pequiguot MEUDON OBSERVATORY FRANCE X Catherine Boisson MEUDON OBSERVATORY FRANCE X Alec Boksenberg ROYAL GREENWICH OBSERVATORY UNITED KING X Robert A. E. Fosbury ESA, EUROPEAN COORDINATING GERMANY, WE X FACILITY ------------------------------------------------------------------------------------ 3. Description of proposed observations. 3a - Image of [OIII]5007 --------------------- The immediate surroundings of the nucleus in any direction and one of the radio lobes can be mapped with the f/96 FOC direct mode with a field of view of 22.5" x 11.2" (1024 x 256, iD Zoom) orientated approximatley east-west: - the 22.5" side parallel to the radio axis (at PA 95D) - the nucleus at approximately (within a few 0.1"): 4.5" from the west (short) side 5" from the north (long) side The [OIII] map is obtained by means of two successive exposures at the same position with: - filter F501N for [OIII] 5007: 4000 sec (total) - filter F502M for continuum : 500 sec Even with roughly homogeneous gas emission a S/N of order of 4 is still obtained at 10 arcsec from the nucleus. Thus any filamentary structure should be easily detected. 3b - Long-slit spectroscopy ---------------------- The long-slit of the f/48 FOC spectrograph (1024x256,1D Zoom) at PA 95D should cross the nucleus, with the west end of the slit at approximately 4" from the nucleus. The position of the slit should be known to better than 0.1" relative to the [OIII]map. Observations in the first order (F305LP filter ~/= 3400 - 5200 A) during 4500 sec. (total). Some idea of the S/N can be get from Table 1 (section 2b). ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. Very high spatial resolution is required. The fine structure in the [OIII] image (filaments, etc ...) will be an important key to understand the nature of the interactions and the evolution of the gas. In addition a precise position of the centre is obtained. Concerning spectrography, the FOC is essential in two respects : (1) the behaviour of stratification in the inner arcsecond will best decide between the different models of the nucleus and (2) velocity information and a few line ratios will be obtained at a comparable resolution to the map up to the edge of the nebulosity. The wavelength range covered by the 1st order of the spectroscopic code contains enough relevant lines to allow a conclusive discussion. The ground-based observations can in the next years usefully improve some line intensities values such as the controversial [OIII]4363 (Appendix 1). However, nothing can be firmly concluded for the ionizing mechanism unless much better than 1 arcsec resolution is achieved. Moreover, maps at the [OIII]5007 obtained from the ground will give a reasonably good idea of the large scale gas distribution but information on any filamentary structure will be missing. Page 3 ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. a - Calibration requirements: ------------------------ f/96 : the absolute flux is not required to be better than 5% relative to celestial standards. Relative fluxes to 5% within the frame are required. Since the f/96 exposure serves in part to determine the pointing postion for the f/48 observations, these direct exposures will require good geometric fidelity. It should be possible to determine the coordinates of an object to better than 0.05 arcsec. f/48 : wavelength calibration should be known to +/- 1/2 pixel across the entire spectral range available. Relative intensities to 5% will be required. b - Dark time : --------- Extended object with faint outer zones. ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. We are familiar with data reduction and analysis of IPCS frames (spectroscopic mode) and CCD images. The software facilities available to us are a VAX 11/780 (VMS 3.4 operating system) at Meudon and an HP 1000 (RTE 6 operating system) at the Institut d'Astrophysique de Paris on which the SPICA-STARLINK + MIDAS-ESO-ECF and IHAP-ESO data resolution packages are installed respectively. There is also a software center (VAX equipped) in Marseille (at the "French Pilot Center for the Space Telescope") which is to remain in close contact with the STScI and ECF. Finally we have access to the STARLINK VAX at RGO. In addition, A. Bijaoui, M. Caillat and D. Pelat are developing on the VAX at Meudon a 2D-data reduction package (EVE) which has the great advantage to be used directly in DCL mode. Part of this package is already user friendly. We rely on the STScI for software related to first step geometric and photometric corrections, wavelength calibrations. However these first steps can be achieved at our home institutes if we receive all the frames allowing to define the instrument characteristics. Concerning modellings, one of us is directly implicated in the building and constant improvement of the detailed photoionization code "PHOTO" (see publications of the last 7 years by Stasinska and/or Pequignot), which is well suited for studying active galactic nuclei (e.g. Pequignot, 1984). Also a new code treating shocks (with or without external radiation source) is now reaching a test phase and should be in operation in 1985 (Stasinska, Pequignot, in preparation). ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). The applicants have free access to all computer facilities for either data analysis or modelling (see section 7). In France there are two organizations which have special lines of credit for Space Telescope observations : INAG and ATP - Telescope Spatial. Programs linked to ST will have high priority in our laboratory. ------------------------------------------------------------------------------------ 13. Observation of the nucleus of NGC 1052 and its eastern 20 arcsecond surroundings with the FOC in both the first order of the long-slit spectroscopic mode and the imaging mode ([OIII]5007). The aim is deciding which mechanism -photoionization by a central source or shock heating - is at work in this archetypal nucleus and studying the interaction between the surrounding medium and the nuclear activity which powers the double radiosource. ------------------------------------------------------------------------------------ 11. Address Information Name: CATHERINE BOISSON Category: CON Institution: OBSERVATOIRE DE MEUDON Address: City: MEUDON PRINCIPAL CEDEX State: Zip Code: Country: FRANCE Telephone: (33)1-534-75-70 Telex (or e-mail): 201571F ------------------------------------------------------------------------------------ Page 4 Name: ALEC BOKSENBERG Category: PI Institution: ROYAL GREENWICH OBSERVATORY Address: MADINGLEY ROAD CB3 0EZ City: CAMBRIDGE State: Zip Code: Country: UNITED KINGDOM Telephone: (44)223-374000 Telex (or e-mail): 817235 ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 1217c [ 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 NGC1052 NUCLEAR REGION OF THE RA = 2H 38M 37.2S +/- 0.1S, 1950 V=1424 EXT 1 V=12.2 +/- 0.5 ACTIVE ELLIPTICAL DEC = -08D 28' 08" +/- 0.1" BKG 2 F-LINE(4861)=1.3 E-15, W- GALAXY NGC 1052 3 LINE(4861)=15 + 4 SURF-LINE(4861)=5 E-15, W- 5 LINE(4861)=6 + SURF-LINE(5007)=6 E-15, W- LINE(5007)= SURF-CONT-BKG(4500)=1.5 +/- 0.2 E- 16 Comments: POSITION IS FROM GASP. IN AGREEMENT WITH THE OPTICAL POSITION OF ARGYLE 1983. FLUX REF. 2 FOR THE COMPACT NUCLEUS, 3 AT 1 ARCSEC FROM NUCLEUS, 4, 5 AT 3 ARCSEC; POINTING TOLERANCE 0.1" FOR LONG SLIT SPECTROSCOPY. ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 1217c [ 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 NGC1052 FOC/96 IMAGE 512X102 F501N 5010 PIXEL=25X25 1 2150S 4 4 1 ORIENT 301D +/- 5D 4 5 DARK TIME / 1-2 GROUP 1-2 WITHIN 1D SAME ORIENT FOR 2 AS 1 Comments: ORIENT 121D +/- 5D IS EQUALLY CYCLE 2 / 1-4 GOOD. GUID TOL 0.020" / 1-4 COND IF TAC OK / 1 -4 ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC1052 FOC/96 IMAGE 512X102 F502M 4950 PIXEL=25X25 1 900S 4 2 1 4 4 ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC1052 FOC/48 ACQ 128X128 F220W 1 300S 1 ONBOARD ACQ FOR 4 -ASLIT ------------------------------------------------------------------------------------------------------------------------------------ 4 NGC1052 FOC/48 SPEC 256X102 G450M 3600- PIXEL=50X25 1 3700S 4 3 1 ORIENT 335D +/- 5D 4-SLIT 5300 Comments: ORIENT 155D +/- 5D IS EQUALLY GOOD. S/N GIVEN FOR A 0.1" X 0.1" RESOLUTION ELEMENT ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 1217c [ 7] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOC/96 FOC/48 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ACQ SPEC ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters PIXEL=25X25 PIXEL=50X25 ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GTO/FOC ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 2.50 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category QUASARS & AGN ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 301D +/- 5D; DARK TIME / 1-2; GROUP 1-2 WITHIN 1D; SAME ORIENT FOR 2 AS 1; CYCLE 2 / 1-4; GUID TOL 0.020" / 1-4; COND IF TAC OK / 1-4; ONBOARD ACQ FOR 4; ORIENT 335D +/- 5D; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F501N F502M F220W G450M ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC1052 ------------------------------------------------------------------------------------------------------------------------------------