THE ROLE OF RADIATION PRESSURE IN THE NARROW LINE REGIONS OF SEYFERT HOST GALAXIES

Journal Article · Fri Jun 10 00:00:00 EDT 2016 · Astrophysical Journal

DOI:https://doi.org/10.3847/0004-637X/824/1/50· OSTI ID:22666190

Davies, Rebecca L.; Dopita, Michael A.; Kewley, Lisa; Groves, Brent; Sutherland, Ralph; Hampton, Elise J.; Banfield, Julie ^[1]; Shastri, Prajval; Kharb, Preeti; Bhatt, Harish ^[2]; Scharwächter, Julia ^[3]; Jin, Chichuan ^[4]; Zaw, Ingyin ^[5]; James, Bethan ^[6]; Juneau, Stéphanie ^[7]; Srivastava, Shweta ^[8]

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1. Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia)
2. Indian Institute of Astrophysics, Sarjapur Road, Bengaluru 560034 (India)
3. LERMA, Observatoire de Paris, PSL, CNRS, Sorbonne Universités, UPMC, F-75014 Paris (France)
4. Max-Planck-Institut für Extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany)
5. New York University (Abu Dhabi), 70 Washington Square S, New York, NY 10012 (United States)
6. Institute of Astronomy, Cambridge University, Madingley Road, Cambridge CB3 0HA (United Kingdom)
7. CEA-Saclay, DSM/IRFU/SAp, F-91191 Gif-sur-Yvette (France)
8. Astronomy and Astrophysics Division, Physical Research Laboratory, Ahmedabad 380009 (India)

We investigate the relative significance of radiation pressure and gas pressure in the extended narrow line regions (ENLRs) of four Seyfert galaxies from the integral field Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7). We demonstrate that there exist two distinct types of starburst-active galactic nucleus (AGN) mixing curves on standard emission line diagnostic diagrams, which reflect the balance between gas pressure and radiation pressure in the ENLR. In two of the galaxies the ENLR is radiation pressure dominated throughout and the ionization parameter remains constant (log U ∼ 0). In the other two galaxies radiation pressure is initially important, but gas pressure becomes dominant as the ionization parameter in the ENLR decreases from log U ∼ 0 to −3.2 ≲ log U ≲ −3.4. Where radiation pressure is dominant, the AGN regulates the density of the interstellar medium on kiloparsec scales and may therefore have a direct impact on star formation activity and/or the incidence of outflows in the host galaxy to scales far beyond the zone of influence of the black hole. We find that both radiation pressure dominated and gas pressure dominated ENLRs are dynamically active with evidence for outflows, indicating that radiation pressure may be an important source of AGN feedback even when it is not dominant over the entire ENLR.

• OSTI ID: 22666190
• Journal Information: Astrophysical Journal, Vol. 824, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BLACK HOLES
DENSITY
EMISSION
FEEDBACK
GALAXY NUCLEI
IONIZATION
RADIATION PRESSURE
SEYFERT GALAXIES
SPECTROSCOPY
STARS