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Title: Enhancement of Feedback Efficiency by Active Galactic Nucleus Outflows via the Magnetic Tension Force in the Inhomogeneous Interstellar Medium

Abstract

By performing three-dimensional magnetohydrodynamics simulations of subrelativistic jets and disk winds propagating into the magnetized inhomogeneous interstellar medium (ISM), we investigate the magnetic effects on the active galactic nucleus feedback. Our simulations reveal that the magnetic tension force promotes the acceleration of the dense gas clouds, since the magnetic field lines, which are initially straight, bend around the gas clouds. In the jet models, the velocity dispersion of the clouds increases with an increase in the initial magnetic fields. The increment of the kinetic energy of the clouds is proportional to the initial magnetic fields, implying that the magnetic tension force increases the energy conversion efficiency from the jet to the gas clouds. Through simulations of the mildly collimated disk wind and the funnel-shaped disk wind, we confirm that such an enhancement of the energy conversion efficiency via the magnetic fields appears even if the energy is injected via the disk winds. The enhancement of the acceleration of the dense part of the magnetized ISM via the magnetic tension force will occur wherever the magnetized inhomogeneous matter is blown away.

Authors:
;  [1];  [2]
  1. National Astronomical Observatory of Japan, Osawa, Mitaka, Tokyo 181-8588 (Japan)
  2. Keio University, Hiyoshi, Kohoku, Yokohama, Kanagawa 223-8522 (Japan)
Publication Date:
OSTI Identifier:
22663655
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 840; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; CLOUDS; DISPERSIONS; EFFICIENCY; ENERGY CONVERSION; FEEDBACK; GALAXY NUCLEI; JET MODEL; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; SHOCK WAVES; SIMULATION; THREE-DIMENSIONAL CALCULATIONS; VELOCITY

Citation Formats

Asahina, Yuta, Ohsuga, Ken, and Nomura, Mariko, E-mail: asahina@cfca.jp. Enhancement of Feedback Efficiency by Active Galactic Nucleus Outflows via the Magnetic Tension Force in the Inhomogeneous Interstellar Medium. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA6C5F.
Asahina, Yuta, Ohsuga, Ken, & Nomura, Mariko, E-mail: asahina@cfca.jp. Enhancement of Feedback Efficiency by Active Galactic Nucleus Outflows via the Magnetic Tension Force in the Inhomogeneous Interstellar Medium. United States. doi:10.3847/1538-4357/AA6C5F.
Asahina, Yuta, Ohsuga, Ken, and Nomura, Mariko, E-mail: asahina@cfca.jp. Mon . "Enhancement of Feedback Efficiency by Active Galactic Nucleus Outflows via the Magnetic Tension Force in the Inhomogeneous Interstellar Medium". United States. doi:10.3847/1538-4357/AA6C5F.
@article{osti_22663655,
title = {Enhancement of Feedback Efficiency by Active Galactic Nucleus Outflows via the Magnetic Tension Force in the Inhomogeneous Interstellar Medium},
author = {Asahina, Yuta and Ohsuga, Ken and Nomura, Mariko, E-mail: asahina@cfca.jp},
abstractNote = {By performing three-dimensional magnetohydrodynamics simulations of subrelativistic jets and disk winds propagating into the magnetized inhomogeneous interstellar medium (ISM), we investigate the magnetic effects on the active galactic nucleus feedback. Our simulations reveal that the magnetic tension force promotes the acceleration of the dense gas clouds, since the magnetic field lines, which are initially straight, bend around the gas clouds. In the jet models, the velocity dispersion of the clouds increases with an increase in the initial magnetic fields. The increment of the kinetic energy of the clouds is proportional to the initial magnetic fields, implying that the magnetic tension force increases the energy conversion efficiency from the jet to the gas clouds. Through simulations of the mildly collimated disk wind and the funnel-shaped disk wind, we confirm that such an enhancement of the energy conversion efficiency via the magnetic fields appears even if the energy is injected via the disk winds. The enhancement of the acceleration of the dense part of the magnetized ISM via the magnetic tension force will occur wherever the magnetized inhomogeneous matter is blown away.},
doi = {10.3847/1538-4357/AA6C5F},
journal = {Astrophysical Journal},
number = 1,
volume = 840,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}
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