Molecular gas in the type 1 Seyfert galaxy NGC 7469 Implications for nuclear activity

Journal Article · Sun Jun 01 04:00:00 EDT 1986 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/164236· OSTI ID:5265927

Heckman, T M; Beckwith, S; Skrutskie, M; Blitz, L; Wilson, A S

The results of a search for 2.12-micron H2 1-0 S(1) line emission from the nuclear (not greater than 1 kpc) region in 11 active galaxies are reported. The galaxies observed included type 1 and type 2 Seyferts, LINERs, and starburst nucleus galaxies. H2 emission was detected in one galaxy, the classical type 1 Seyfert NGC 7469. Also reported is the detection of very luminous C-12O 2.6-mm emission from NGC 7469, and optical narrow-band images and long-slit spectroscopy data concerning the ionized gas in this galaxy are presented. These data imply that NGC 7469 not only contains a highly active compact nucleus but also is undergoing a luminous circumnuclear (few-kpc scale) starburst. Most of the other galaxies with known H2 emission also seem to be composite monster/starburst systems and/or interacting galaxies. This result may arise because the molecular gas is associated with the starburst, while the primary form of the mechanical energy necessary to shock-excite the H2 is either outflow (possibly a wind) driven by the compact active nucleus or noncircular motions of gravitational origin. In either case, high-velocity (greater than 300 km/s) collisions between dense molecular clouds and a more ubiquitous, less dense gas phase can drive slow (10-30 km/s) shocks into the molecular clouds, exciting the observed H2 emission. 68 references.

• Research Organization: Maryland Univ., College Park; Johns Hopkins Univ., Baltimore, MD; Cornell Univ., Ithaca, NY; Hawaii Univ., Honolulu
• OSTI ID: 5265927
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 305; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
COSMIC GASES
ELEMENTS
EMISSION SPECTRA
FLUIDS
GALAXIES
GALAXY NUCLEI
GASES
HYDROGEN
INFRARED SPECTRA
MOLECULES
NONMETALS
OXIDES
OXYGEN COMPOUNDS
SEYFERT GALAXIES
SPECTRA
STAR EVOLUTION