5850( 0) - 07/18/95 18:16 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 5850 Version: ********** Check-in Date: ********** 1.Proposal Title: A Definitive Test for the Excitation Mechanism of LINERs ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle AGN GO 5 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Michael A. Dopita Mt. Stromlo and Siding Spring Observatories CoI: Anuradha Koratkar Space Telescope Science Institute Y CoI: Geoffrey V. Bicknell Mt. Stromlo and Siding Spring N Observatories CoI: Ralph S. Sutherland JILA, University of Colorado N CoI: John F. Hawley Virginia Institute for Theoretical N Astronomy, U. of Virginia CoI: Elaine Sadler Dept. of Physics, U. of Sydney N CoI: Mark Allen Mt. Stromlo and Siding Spring N Observatories ------------------------------------------------------------------------------------ 6. Abstract We propose to undertake a definitive test which will determine whether LINERs are photoionised or shock ionised, by obtaining a single FOS spectrum of the bright, nearby and unreddened accretion disk of M87 from 1150 - 6800 Angstrom. At visible wavelengths, the emission-line diagnostics which might distinguish between excitation mechanisms are ambiguous. However, models generated using our shock and photoionisation code MAPPINGS II, shows that a comparison between the optical and the UV line intensities produces an unambiguous diagnostic. The shock produces a strong UV emission line spectrum, and the photoionisation mechanism does not. If LINER nuclei turn out to be shock excited, we will be able to compare the results with the predictions of the magnetic instability model of Balbus and Hawley (1991) which provides both a means of angular momentum transport in accretion disks, and of shock generation in the outer atmospheric layers of such disks. This would provide a powerful new insight into the accretion process of AGN, and open up the way for a quantitative understanding of the LINER phenomenon. ------------------------------------------------------------------------------------ 5850( 0) - 07/18/95 18:16 - [ 2] Observations Description ------------------------ In Cycle 5 we propose to obtain a complete, high quality spectrum of a single region of the M87 accretion disk at a radial distance of 0.5 arc sec. from the nucleus, using the 0.86 as circular aperture of FOS. We would obtain FOS/BL spectrophotometry in the range 1150-4500Angstrom using the G130H, G190H gratings and Prism , and FOS/RD spectrophotometry in the range 2221- 6740Angstrom using G270H , G400H, and G570 gratings. Tho optical spectra are necessary to properly normalise the UV spectra to the optical. We aim to achieve a sensitivity which is sufficient to detect lines as faint as 5% of H- beta throughout the UV and optical spectrum. The FOS/BL Prism observation is needed to ensure reliable calibration between the FOS/BL and the FOS/RD observations. Real Time Justification ----------------------- For the FOS spectrophotometry to be used as input to modelling codes, all the observations on the blue side, and all the observations on the red side need to be obtained contiguously, and without interruption. The proposed observation is entirely self-contained. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: Contact_Address Ship Via: UPS Email: koratkar@stsci.edu , ------------------------------------------------------------------------------------ 5850( 0) - 07/18/95 18:16 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 NGC4486 Galaxy, Elliptical, RA=12H 30M 49.4286S +/- 0.3S, J2000 V=16.7 E(B-V)= 0.01 Liner DEC=+12D 23' 27.985" +/- 0.3", PLATE-ID=00IY 2 NGC4486- Galaxy, Elliptical, R=0.6", PA=201D, FROM 1, PLATE- J2000 V=16.25 E(B-V)= 0.01 OFFSET Liner ID=00IY 5850( 0) - 07/18/95 18:16 - [ 4] 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, 1 11S ONBOARD ACQ FOR 2 ARY FAINT=1320 ------------------------------------------------------------------------------------------------------------------------------------ 2 NGC4486 FOS/RD ACQ/PEA 0.3 MIRROR SEARCH-SIZE- 1 25S ONBOARD ACQ FOR 3 K X=5, SEARCH- SIZE-Y=5, SCAN- STEP-X=0.11, SCAN-STEP- Comments: Y=0.11 ------------------------------------------------------------------------------------------------------------------------------------ 3 NGC4486- FOS/RD ACQ 4.3 MIRROR 1 600S OFFSET ------------------------------------------------------------------------------------------------------------------------------------ 4 NGC4486- FOS/RD ACCUM 1.0 G270H 1 1200S OFFSET ------------------------------------------------------------------------------------------------------------------------------------ 5 NGC4486- FOS/RD ACCUM 1.0 G400H 1 900S OFFSET ------------------------------------------------------------------------------------------------------------------------------------ 6 NGC4486- FOS/RD ACCUM 1.0 G570H 1 900S OFFSET ------------------------------------------------------------------------------------------------------------------------------------ 7 NGC4486- FOS/BL ACCUM 1.0 G190H 1 1500S OFFSET ------------------------------------------------------------------------------------------------------------------------------------ 8 NGC4486- FOS/BL ACCUM 1.0 G130H 1 4000S OFFSET ------------------------------------------------------------------------------------------------------------------------------------ 9 NGC4486- FOS/BL ACCUM 1.0 PRISM 1 1100S OFFSET ------------------------------------------------------------------------------------------------------------------------------------ 5850( 0) - 07/18/95 18:16 - [ 5] Summary Form for Proposal 5850 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOS/RD FOS/BL ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/BINARY ACQ/PEAK ACQ ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BRIGHT=660000 FAINT=1320 SCAN-STEP-Y=0.11 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category AGN ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 2 ONBOARD ACQ FOR 3 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G270H G400H G570H G190H G130H PRISM ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC4486 NGC4486-OFFSET ------------------------------------------------------------------------------------------------------------------------------------