! File: 1223C.PROP ! Database: PEPDB ! Date: 16-FEB-1994:06:42:51 coverpage: title_1: STUDY OF THE NUCLEUS OF THE SEYFERT 2 GALAXY NGC 5728 sci_cat: QSO, AGN,SEYFERTS proposal_for: GTO/FOC pi_fname: ALEC pi_lname: BOKSENBERG pi_inst: ROYAL GREENWICH OBSERVATORY pi_country: UNITED KINGDOM pi_phone: 0223 374000 keywords_1: SEYFERT GALAXY hours_pri: 1.00 num_pri: 1 pi_position: PROFESSOR ! end of coverpage abstract: line_1: Seyfert 2 galaxies are most probably photoionized. The nature of the line_2: nonthermal continuum responsible for this photoionization is unknown; it has line_3: been seen in only one case, NGC 1068. NGC 5728 is a Seyfert 2 galaxy with an line_4: extended (~10") nuclear emission region (probably the most extended known). line_5: High angular resolution images, in the UV to get rid of the stellar continuum, line_6: through narrow band filters chosen to isolate emission lines or the continuum line_7: may allow the detection of a possibly extended non-thermal continuum and the line_8: similarity or the difference of its morphology with that of the emission line_9: nebulosity. line_11: This could be a first step in understanding the nature of this continuum. ! ! end of abstract general_form_proposers: lname: VERON fname: PHILIP inst: HAUTE PROVENCE OBSERVATORY country: FRANCE esa: X ! lname: BOKSENBERG fname: ALEC inst: ROYAL GREENWICH OBSERVATORY country: UNITED KINGDOM esa: X ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: We propose to observe NGC 5728 with the FOC in the F/96 mode with the 512 x 512 line_2: pixels format, providing a field of vbiew of 11.2 x 11.2 arcsec, adequate for line_3: this object. line_5: Three sets of exposures are requested, one through each of the following line_6: filters: line_8: F152M LambdaLambda 1450-1600 c IV Lambda 1550; peak transmission 15% line_9: F140M LambdaLAmbda 1350-1450 continuum 15% line_10: F170M LambdaLambda 1600-1800 He II Lambda 1640 20% line_12: (The heliocentric radial velocity of NGC 5728 is V = 2800 km s^-1). line_14: The target is an extended nebulosity with, most probably, a large range of line_15: surface brightness, therefore exposure times, required signal-to-noise ratio, line_16: etc...., cannot be defined accurately. ! question: 4 section: 1 line_1: These observations cannot be made from the ground, not only because the best line_2: photographs obtainable have a resolution limited by the seeing to ~0.7", but line_3: also because it is essential to work in the UV to avoid the very strong line_4: starlight contamination due to the bulge of the galaxy which makes it line_5: impossible to detect in the visible very faint non-thermal extensions. ! question: 6 section: 1 line_1: Filter F152M and F140M both transmit some OI airglow emission; a dark sky line_2: (solar zenith angle larger than 100D) is definitely required for the exposure line_3: with the F140M filter and probably for the exposures with the F152M filter as line_4: well. ! question: 7 section: 1 line_1: The ESO image processing system IHAP, on an HP computer, has been used line_2: extensively by us to reduce CCD frames. It seems to contain most, if not all line_3: the functions required for this project. In addition we will have access to the line_4: STARLINK CAVAD clusterat RGO for data reduction. ! question: 10 section: 1 line_1: We expect that our institutions will support us. ! question: 13 section: 1 line_1: Seyfert 2 galaxies are most probably photoionized. The nature of the nonthermal line_2: continuum responsilbe for this photoionization is unknown; it has been seen in line_3: only one case, NGC1068. NGC5728 is a Seyfert 2 galaxy with an extended (~10") line_4: nuclear emission region (probably the most extended known). High angular line_5: resolution images, in the UV to get rid of the stellar continuum, through line_6: narrow band filters chosen to isolate emission lines or the continuum may allow line_7: the detection of a possibly extended non-thermal continuum and the similarity line_8: or the difference of its morphology with that of the emission nebulosity. This line_9: could be a first step in understanding the nature of this continuum. ! !end of general form text general_form_address: lname: VERON fname: PHILIP category: CON inst: OBSERVATOIRE DE HAUTE PROVENCE addr_1: F-04870 SAINT-MICHEL L'OBSERVATOIRE country: FRANCE phone: (92) 766368 telex: 410690 ! lname: BOKSENBERG fname: ALEC title: PROF. category: PI inst: ROYAL GREENWICH OBSERVATORY addr_1: MADINGLEY ROAD addr_2: CB3 0EZ city: CAMBRIDGE country: UNITED KINGDOM phone: (44) 223 374000 telex: 817235 ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: NGC5728 descr_1: SEYFERT 2 GALAXY pos_1: RA=14H 39M 36.85S +/- 0.03S, pos_2: DEC=-17D 02' 28.34" +/- 0.5" equinox: 1950 pm_or_par: N rv_or_z: V=2970 acqpr_1: EXT plate_req: N plate_avail: N comment_1: GASP COG MEASURE USED fluxnum_1: 1 fluxval_1: V=12.5 +/- 0.3 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 1.000 targname: NGC5728 config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F152M wavelength: 1500 num_exp: 1 time_per_exp: 1000S priority: 1 req_1: DARK TIME / 1-3; req_2: CYCLE 2 / 1-4; req_3: GUID TOL 0.020" / 1-4; req_4: COND IF TAC OK / 1-4; ! linenum: 3.000 targname: NGC5728 config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F140M wavelength: 1390 num_exp: 1 time_per_exp: 1000S priority: 2 ! linenum: 4.000 targname: NGC5728 config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F170M wavelength: 1760 num_exp: 1 time_per_exp: 1000S priority: 2 ! ! end of exposure logsheet ! No scan data records found