Contents of: VI/111/./abstract/HSMITH_AGN_A_2.abs

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SCIENTIFIC ABSTRACT
We propose spectroscopic survey observations and individual line
observations using LWS, SWS, and ISOPHOT designed to provide the
first complete spectral characterization of AGN in the 3-200
micron region. The major goals of the program are to:

a) distinguish between non-stellar engine and starburst origins
of the luminosity in galactic nuclei (emission line ratios
sensitive to density and excitation will identify all of the
current classes of nuclear activity, discriminating between
thermal and nonthermal models),

b) measure the distribution and kinematics of nuclear gas and
probe the dynamical geography of the nucleus via line profile
shape analysis,

c) study the nature and the origin of the coronal line emission
region of AGN,

d) measure heavy element abundances in AGN,

e) determine accurately how dust obscures the intrinsic AGN
spectra,

f) search for the postulated hidden BLR in ``narrow-line'' AGNs,

g) search for molecules in thick tori (Seyfert 2) and outer
regions of accretion disks and study their kinematics at high
spectral resolution,

h) determine the importance of thermal and nonthermal emission
for the continua of all classes of AGNs and the shape of the
far infrared continuum turnover, and

i) measure the detailed continuum energy distribution of AGN,
with emphasis on high z QSOs for which we will address questions
about the formation of heavy elements at very large z, the
formation of galaxies and its relation with QSOs, the structure and
the energetics of host galaxies of QSOs.


OBSERVATION SUMMARY
This program includes observation of roughly 50 AGN and QSOs.  The
majority of AGN will be spectroscopically surveyed using LWS, SWS,
and
ISOPHOT grating spectra; distant QSOs will use PHOT22. All of the
survey spectra will cover the full wavelength range at the full
resolving power afforded by the grating subsystem of each
instrument.
Full SWS scans on NGC 1068 and NGC 4151 are omitted to avoid
duplication with the SWS team Guaranteed time proposal "Infrared          
Spectroscopy of Bright Galactic Nuclei and the Connection between
Starformation and AGN's". Similarly, PHT spectroscopy on a number
of
our program objects (I Zw 1, Mkn 551, and Mkn 463) are omitted to
avoid duplication with the SWS team proposal.) The SWS and PHT
observation
times (including SWS01, SWS02, and SWS06 AOTs) are designed to
achieve a
signal to noise ratio of twenty to several hundred on the continuum
of each
object. The lowest signal to noise occurs in SWS01 scans shortward
of 7
microns. The survey AOTs utilized are LWS01, SWS01, and PHT40.
Specific line
observations utilize SWS02 and SWS06. In all cases, SWS01
observations will
be made in full R mode, and LWS01 observations will be Nyquist
sampled over
45-180 microns.
Depending on the wavelength range, a signal to noise
ratio of twenty to several hundred on the continuum 
will be obtained for each object. 
For most of the targets these correspond to 
10-sigma detections of emission lines with fluxes of
5.0e-17 Watts/meter2 in the most sensitive wavelength regions
(around 100um).  In the least sensitive detector bands
(at the shortest wavelengths), lines of this flux would 
typically be detected at only the 2-sigma level.
Higher signal-to-noise ratios will be obtained for the
two brightest archetypical AGNs, the Seyfert 1 NGC 4151,
and the Seyfert 2 NGC 1068, allowing detection of even
fainter lines in these two special cases.

In addition to these survey observations, high quality line
profiles will be obtained on lines listed in Table 1a and 1b below.
These lines are chosen to included all ISO observable ionization
states of neon. Transitions of several other intermediate mass
elements are included to yield abundances and to produce a data set
that spans a wide range of transition critical densities to probe
AGN dynamical structure.   All SWS02 observations in the program
pertain to Table 1. Observations of Mkn 3, I Zw 1, NGC 3783, Mkn
573, and Mkn 463 with SWS02 will observe lines listed in Table 1b
to avoid duplication with the SWS team proposal. The remainder of
our SWS02 and SWS06 observations will observe lines listed in Table
1a. Observations with SWS02 or SWS06 will also be made on lines
listed in Table 2 during follow up time only, and where no
duplication with the SWS team observations exist. Observations made
with
SWS06 cover a 2000 km/s spectral baseline centered on the line. 

We propose to obtain high-resolution Fabry-Perot scans for the profiles
of two emission lines expected to be strong in the Seyfert 2 nucleus
of NGC 1068: [O I] 63um and the CO (J=57-->56) line at 46um.
While this is a top sientific priority, we have listed it as priority 3 because
the priority 1 grating scans should sensibly be examined first.
Both will reveal the presence of high-density, but low-ionization
gas--in particular the dense molecular gas that is believed to
form a thick obscuring torus surrounding the central engine
(eg., Krolik and Begelman 1988).  This dense region is probably
too optically thick to emit strong lines at much shorter wavelengths.
The trade-of

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