J/ApJ/616/707 Circumnuclear structure of NICMOS galaxies (Hunt+, 2004)
Circumnuclear structure and black hole fueling: Hubble Space Telescope NICMOS
imaging of 250 active and normal galaxies.
Hunt L.K., Malkan M.A.
<Astrophys. J., 616, 707-729 (2004)>
=2004ApJ...616..707H 2004ApJ...616..707H
ADC_Keywords: Morphology ; Active gal. nuclei ; Galaxies, IR
Keywords: galaxies: active - galaxies: nuclei - galaxies: Seyfert -
galaxies: starburst - galaxies: structure - infrared: galaxies
Abstract:
Why are the nuclei of some galaxies more active than others? If most
galaxies harbor a central massive black hole, the main difference is
probably in how well it is fueled by its surroundings. We investigate
the hypothesis that such a difference can be seen in the detailed
circumnuclear morphologies of galaxies using several quantitatively
defined features, including bars, isophotal twists, boxy and disky
isophotes, and strong nonaxisymmetric features in unsharp-masked
images. These diagnostics are applied to 250 high-resolution images of
galaxy centers obtained in the near-infrared with NICMOS on the Hubble
Space Telescope. To guard against the influence of possible biases and
selection effects, we have carefully matched samples of Seyfert 1,
Seyfert 2, LINER, starburst, and normal galaxies in their basic
properties, taking particular care to ensure that each was observed
with a similar average scale (10-15pc/pixel).
Description:
We have acquired HST NICMOS F160W images of 30 Seyfert galaxies in a
GO Snapshot Program (ID 5479; PI: M. A. Malkan). Our GO snapshots have
been augmented with other F160W snapshot images from the HST archive
acquired with all three NICMOS cameras (Pogge-ID 7867; Mulchaey-ID
7330; Sparks-ID 7919; Stiavelli-ID 7331; Peletier-ID 7450).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 101 165 Sample properties
table4.dat 101 78 Properties of 78 of the 85 rejected galaxies
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Byte-by-byte Description of file: table2.dat table4.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- AType Activity class
12- 23 A12 --- Name Object name
24- 25 A2 --- f_Name [d*] Eliminated galaxy (1)
28- 33 F6.3 --- z Redshift
35- 39 F5.1 Mpc Dist Distance
41- 59 A19 --- MType The RC3 (Cat. VII/155) morphology type
61- 64 F4.1 arcmin MajAxis Optical major axis
66- 69 F4.1 arcmin MinAxis Optical minor axis
71- 74 F4.1 mag Bmag The apparent B band magnitude
76- 80 F5.1 mag BMAG The absolute B band magnitude
82- 85 F4.1 pc/pix Scale Relative spatial resolution
87- 88 A2 --- Bar [Y? ] Bar found?
90- 91 A2 --- Twist [Y? ] Isophotal twist found?
93- 94 A2 --- 3theta [Y? ] Large 3θ residual term found?
96- 99 A4 --- cos4 [DB? ] Boxy/disky isophote found (2)
101 A1 --- USM [±] High-amplitude non-axisymmetric
structure (3)
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Note (1): Flag on Name, defined as follows:
* = Eliminated in the DMS because distance>80Mpc.
d = Eliminated in the IMS because inclination>70 degrees.
Note (2): The isophote found is defined as follows:
B = Boxy;
D = Disky.
Note (3): Unsharp masks which have any 180-parsec boxes which deviate
from the smooth model fit by more than ±27%; those with positive
deviations are designated with "+", and negative ones with "-".
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 01-Jun-2005