6297( 8) - 05/22/96 17:25 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6297 Version: 8 Check-in Date: 22-May-1996 17:21:59 1.Proposal Title: Probing the Black Hole Environment: The Nuclear Spectrum of M87 ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle AGN GTO 5 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Holland Ford Johns Hopkins University CoI: Zlatan Tsvetanov Johns Hopkins University Y CoI: Gerard Kriss Johns Hopkins University N CoI: Richard Harms RCH Scientific N CoI: Bruce Margon University of Washington N CoI: Margaret Burbidge University of California San Diego N CoI: Angel Roger University of Arozona N CoI: Edward Beaver University of California San Diego N CoI: Frank Bartko University of Colorado N CoI: Ralph Bohlin Space Telescope Science Institute N CoI: Arthur Davidsen Johns Hopkins University N ------------------------------------------------------------------------------------ 6. Abstract NGC5252 contains one of the most spectacular examples of ionization cones observed in Seyfert galaxies extending out to several tens of kpc from the nucleus with cone axis almost perfectly aligned with the linear radio source. Our narrow- band WFPC-2 images obtained in cycle 4 have revealed a complex circumnuclear morphology of the line emitting gas with an apparent nuclear disk-like structure seen egde-on and oriented roughly perpendicular to the radio axis plus several ``spiral'' arms, arcs and other signatures of distributed ISM around the nucleus. We propose to obtain FOS spectra at three positions along the apparent nuclear disk revealed by the WFPC -2 images and one centered on the brightest extranuclear position located within the opening angle, but close to the edge of the ionization cone. The main goals of this study are: (1) to measure the kinematics of the nuclear disk from the velocity displacements and profiles of the emission lines at the nucleus and at two opposite sides which may allow us to obtain an estimate of the mass encircled in a small volume at the nucleus; (2) based on line ratios from a wide wavelenght range (in combination with ground-based imaging, spectroscopy and F-P measurements) to study the physical conditions in the line emitting gas both in the nuclear disk and in the EELR within the ionization cone. ------------------------------------------------------------------------------------ 6297( 8) - 05/22/96 17:25 - [ 2] Observations Description ------------------------ Selected FOS aperture positions are shown in Fig.\\ 1. For estimating the exposure times we have used two independently obtained ground-bages spectra to flux calibrate our WFPC-2 H- alpha+N II\\ image. To our satisfaction the two callibrations were differing by only ~10\\ fluxes at the proposed FOS positions were then measured from the callibrated image and other emission lines were scaled according to ratios suggested by the spectra. (1) To study the kinematics of the emission line gas in the immediate vicinity of the nucleus of NGC5252 we propose to take FOS spectra of the three peaks in the nuclear disk seen on our WFPC2 images (Fig.\\ 1). We will use the 0\\as3 aperture and the G570H grating which covers the brightest emission lines - O Iii\\ and H-alpha+N II. To assure a common wavelength scale we will take one or more wavelength calibration spectra. Estimated exposure times are set up to secure ~1000 counts in the H-alpha+N II\\ line complex and somewhat more in the O Iii\\ line. Experience with the analysis of the M87 spectra shows that this will allow us accurate velocity measurements and some evaluation of the profile. Without the overhead these times are: 1000 s (POS1), 1200 s (POS2), and 1600 s (POS3). (2) Physical conditions in the nuclear gaseous disk. To study the physical conditions in the nuclear gaseous disk we propose to obtain G400H, G270H, and G160L FOS/RD spectra at the position of the central peak. The appropriate exposure times are: 1000 s (G400H), 2400 s (G270H) and 2400 s (G160L). Combined with the kinematics measurements in (1) these require a total of 5 orbits. (3) To study the dominant energy supply mechanism in the EELR we propose to obtain UV spectra at the brightest off-nucleus position - POS4 in Fig.\\ 1. We will use the 1\\as0 FOS aperture (0\\as86 in fact) since spatial resolution is not critical in this case. This will also helps in combining the FOS spectra with ground-based data. We plan to use the G160L and G270H gratings in combination with the FOS/RD detector. Like in the case of the nuclear positions we have measured the H-alpha+N II\\ flux from our WFPC-2 image. Suggested exposure times are based on the ability to detect the primary discriminant line, C IV, as weak as 50\\ require ~90 min (2 orbits) for the G160L grating at the off- nucleus position. We note here that the C IV\\ line is redshited just enough to make it possible to use the red detector instead of the blue one. And finally, we have tested the acquisition of the target using a scaled version of our WFPC -2 images and the current-to-date binary serch FOS simulator. These tests have assured us that we can use an initial BS with a subsequent two stage peak-up to acquire the brightest nuclear peak in one orbit. The grand total request is therefore 8 orbits. Real Time Justification ----------------------- None. We would like to stress again that our HST observations are stronly supported by an extensive ground-based work. We have already obtained narrow- band imaging, long-slit spectra at several position angles, and a detailed Fabry-Perot set of data. To these we will add a deep long slit spectrum down to the atmospheric cut-off of which includes our off-nucleus position. This will be used in combination with the FOS UV spectra to study the relative importance of different ionizing/excitation processes in the outflowing gas. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 6297( 8) - 05/22/96 17:25 - [ 3] Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: , ------------------------------------------------------------------------------------ 6297( 8) - 05/22/96 17:25 - [ 4] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC4486 GALAXY RA=12H 30M 49.4286S +/- 0.3", 2000 V=1200 V = 16.7 DEC=+12D 23' 27.985" +/- 0.3", E(B-V) = 0.01 PLATE-ID=00IY 6297( 8) - 05/22/96 17:25 - [ 5] Visit: 01 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC4486 FOS/RD ACQ/BIN 4.3 MIRROR BRIGHT=660000,FAINT=1320 1 11 S ONBOARD ACQ FOR 2 ARY ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC4486 FOS/RD ACQ/PEA 0.25-PA MIRROR SEARCH-SIZE-X=5,SEARCH-SIZE-Y=5, 1 12 S ONBOARD ACQ FOR 3 K IR-A SCAN-STEP-X=0.15,SCAN-STEP-Y=0.15 Comments: Using STEP-PATT=SINGLE which is the default for ACQ/PEAK with the paired apertures. ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC4486 FOS/RD ACQ/PEA 0.25-PA MIRROR SEARCH-SIZE-X=3,SEARCH-SIZE-Y=3, 1 12 S ONBOARD ACQ FOR 4-10 K IR-A SCAN-STEP-X=0.05,SCAN-STEP-Y=0.05 Comments: Using STEP-PATT=SINGLE which is the default for ACQ/PEAK with the paired apertures. ------------------------------------------------------------------------------------------------------------------------------------ 4 NGC4486 FOS/RD ACCUM 0.25-PA G570H STEP-PATT=SINGLE 1 2300 S IR-A ------------------------------------------------------------------------------------------------------------------------------------ 5 WAVE FOS/RD ACCUM 0.25-PA G570H STEP-PATT=SINGLE 1 DEF IR-A ------------------------------------------------------------------------------------------------------------------------------------ 6 NGC4486 FOS/RD ACCUM 0.25-PA G400H STEP-PATT=SINGLE 1 2300 S IR-A ------------------------------------------------------------------------------------------------------------------------------------ 7 WAVE FOS/RD ACCUM 0.25-PA G400H STEP-PATT=SINGLE 1 DEF IR-A ------------------------------------------------------------------------------------------------------------------------------------ 8 NGC4486 FOS/RD ACCUM 0.25-PA G270H STEP-PATT=SINGLE 1 2300 S IR-A ------------------------------------------------------------------------------------------------------------------------------------ 9 WAVE FOS/RD ACCUM 0.25-PA G270H STEP-PATT=SINGLE 1 DEF IR-A ------------------------------------------------------------------------------------------------------------------------------------ 10 NGC4486 FOS/BL ACQ/PEA 0.25-PA MIRROR SEARCH-SIZE-X=5,SEARCH-SIZE-Y=5, 1 20 S ONBOARD ACQ FOR 11-14 K IR-A SCAN-STEP-X=0.05,SCAN-STEP-Y=0.05 Comments: Using STEP-PATT=SINGLE which is the default for ACQ/PEAK with the paired apertures. ------------------------------------------------------------------------------------------------------------------------------------ 11 NGC4486 FOS/BL ACCUM 0.25-PA G160L STEP-PATT=SINGLE 1 400 S IR-A ------------------------------------------------------------------------------------------------------------------------------------ 12 WAVE FOS/BL ACCUM 0.25-PA G160L STEP-PATT=SINGLE 1 DEF IR-A ------------------------------------------------------------------------------------------------------------------------------------ 13 NGC4486 FOS/BL ACCUM 0.25-PA G160L STEP-PATT=SINGLE 1 2300 S IR-A ------------------------------------------------------------------------------------------------------------------------------------ 6297( 8) - 05/22/96 17:25 - [ 6] Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 14 WAVE FOS/BL ACCUM 0.25-PA G160L STEP-PATT=SINGLE 1 DEF IR-A ------------------------------------------------------------------------------------------------------------------------------------ 6297( 8) - 05/22/96 17:25 - [ 7] Summary Form for Proposal 6297 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOS/RD FOS/BL ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/BINARY ACQ/PEAK ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BRIGHT=660000 FAINT=1320 SCAN-STEP-Y=0.15 SCAN-STEP-Y=0.05 STEP-PATT=SINGLE SCAN-STEP-X=0.05 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GTO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category AGN ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 2 ONBOARD ACQ FOR 3 ONBOARD ACQ FOR 4-10 ONBOARD ACQ FOR 11-14 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G570H G400H G270H G160L ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC4486 WAVE ------------------------------------------------------------------------------------------------------------------------------------