Beitr�ge zur Polarographie

Stoll, W. G.; Berbalk, H.

doi:10.1007/bf00904142

Cited by 11 publications

(8 citation statements)

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“…For the only Seyfert 1 galaxy that we have found to have an outflow, Mrk 6, the energy outflow rate of its lower velocity component (10 41.6 ( Ω 0.1 ) ( r 5 kpc ) ergs s −1 ) is again ∼1% of the host bolometric luminosity. This indicates that this Seyfert 1 outflow is also not energetic enough to play a vital role in galactic feedback, and thus previous findings are consistent with our results (Krongold et al 2007;Stoll et al 2009). If we look at the higher velocity outflow found in Mrk 6, its energy outflow rate (10 42.9 ( Ω 0.1 ) ( r 5 kpc ) ergs s −1 ) is ∼5% of the host bolometric luminosity, which is higher than for the Seyfert 2 galaxies but again likely not strong enough to influence the evolution of its environment.…”

Section: Outflow Dynamicssupporting

confidence: 92%

Neutral Gas Outflows and Inflows in Infrared-Faint Seyfert Galaxies

Krug¹,

Rupke²,

Veilleux³

2009

ApJ

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Previous studies of the Na I D interstellar absorption line doublet have shown that galactic winds occur in most galaxies with high infrared luminosities. However, in infrared-bright composite systems where a starburst coexists with an active galactic nucleus (AGN), it is unclear whether the starburst, the AGN, or both are driving the outflows. The present paper describes the results from a search for outflows in 35 infrared-faint Seyferts with 10 9.9 < L IR /L ⊙ < 10 11 , or, equivalently, star formation rates (SFR) of ∼0.4 -9 M ⊙ yr −1 , to attempt to isolate the source of the outflow. We find that the outflow detection rates for the infrared-faint Seyfert 1s (6%) and Seyfert 2s (18%) are lower than previously reported for infrared-luminous Seyfert 1s (50%) and Seyfert 2s (45%). The outflow kinematics of infrared-faint and infrared-bright Seyfert 2 galaxies resemble those of starburst galaxies, while the outflow velocities in Seyfert 1 galaxies are significantly larger. Taken together, these results suggest that the AGN does not play a significant role in driving the outflows in most infrared-faint and infrared-bright systems, except the high-velocity outflows seen in Seyfert 1 galaxies. Another striking result of this study is the high rate of detection of inflows in infraredfaint galaxies (39% of Seyfert 1s, 35% of Seyfert 2s), significantly larger than in infrared-luminous Seyferts (15%). This inflow may be contributing to the feeding of the AGN in these galaxies, and potentially provides more than enough material to power the observed nuclear activity over typical AGN lifetimes.

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Section: Outflow Dynamicssupporting

confidence: 92%

Neutral Gas Outflows and Inflows in Infrared-Faint Seyfert Galaxies

Krug¹,

Rupke²,

Veilleux³

2009

ApJ

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“…He found ǫ k ranges between 10 −6 and 10 −3 . Our models also agree with the relatively low energy and mass feedback efficiencies found by Krongold et al (2007) and Stoll et al (2009) who studied of X-ray and UV absorbing outflows in Seyfert galaxies. On the other hand, the AGN evolution and the BH growth synthesis model of Merloni & Heinz (2008), combined with the observed star formation rate history of the universe, suggests that ǫ k = (3 − 5)×10 −3 , which is about an order of magnitude larger than the value found in our models.…”

Section: Comparisons With Other Studiessupporting

confidence: 91%

On the Feedback Efficiency of Active Galactic Nuclei

Kurosawa

Proga

Nagamine

2009

ApJ

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We measure and analyze the energy, momentum, and mass feedback efficiencies due to radiation from active galactic nuclei (AGN) in relatively large scale outflows (from ∼ 0.01 to ∼ 10 pc). Our measurements are based on the two-dimensional (axisymmetric) and time-dependent radiationhydrodynamical simulations recently presented in Kurosawa & Proga. In that paper, we studied outflows from a slowly rotating (sub-Keplerian) infalling gas driven by the energy and pressure of the radiation emitted by the AGN. These simulations follow dynamics of gas under the influence of the gravity of the central 10 8 M ⊙ black hole on scales from ∼ 0.01 to ∼ 10 pc. They self-consistently couple the accretion-luminosity with the mass inflow rate at the smallest radius (our proxy for the mass-accretion rate,Ṁ a ). Over thirty simulations have been performed to investigate how the results depend on the gas density at the outer radius, ρ o . A key feature of these simulations is that the radiation field and consequently the gas dynamics are axisymmetric, but not spherically symmetric. Therefore, the gas inflow and outflow can occur at the same time. We compare ourṀ a -ρ o relation with that predicted by the Bondi accretion model. For high luminosities comparable to the Eddington limit, the power-law fit (Ṁ a ∝ ρ q o ) to our models yields q ≈ 0.5 instead of q = 1.0 which is predicted by the Bondi model. This difference is caused by the outflows which are important for the overall mass budget at high luminosities. The maximum momentum and mass feedback efficiencies found in our models are ∼ 10 −2 and ∼ 10 −1 , respectively. However, the outflows are much less important energetically: the thermal and kinetic powers in units of the radiative luminosity are ∼ 10 −5 and ∼ 10 −4 , respectively. In addition, the efficiencies do not increase monotonically with the accretion luminosity but rather peak around the Eddington limit beyond which a steady state disk-wind-like solution exists. Our energy feedback efficiencies are significantly lower than 0.05, which is required in some cosmological and galaxy merger simulations. The low feedback efficiencies found here could have significant implications on the mass growth of super massive black holes in the early universe. We stress however that we have not considered the innermost parts of the accretion and outflow where radiation and matter interact most strongly. The feedback from this region could have efficiencies significantly above the low values found here.

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“…But the best estimates from either of these sources might be in the range 1 × 10 −3 > ǫ w > 3 × 10 −4 (Proga, Stone & Kallman 2000;Proga & Kallman 2004;Krongold et al 2007;Stoll et al 2009;Kurosawa, Proga & Nagamine 2009), a factor of 5 to 17 smaller than the commonly adopted values and in a range where η 1 if v w,10 ≈ 1. A specific example may be useful.…”

Section: Introductionmentioning

confidence: 78%

Momentum Driving: Which Physical Processes Dominate Active Galactic Nucleus Feedback?

Ostriker

Choi

Ciotti

et al. 2010

ApJ

276

291

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The deposition of mechanical feedback from a supermassive black hole (SMBH) in an active galactic nucleus (AGN) into the surrounding galaxy occurs via broad-line winds which must carry mass and radial momentum as well as energy. The effect can be summarized by the dimensionless parameteris the efficiency by which accreted matter is turned into wind energy in the disc surrounding the central SMBH. The outflowing mass and momentum are proportional to η, and many prior treatments have essentially assumed that η = 0. We perform one-and two-dimensional simulations and find that the growth of the central SMBH is very sensitive to the inclusion of the mass and momentum driving but is insensitive to the assumed mechanical efficiency. For example in representative calculations, the omission of momentum and mass feedback leads to an hundred fold increase in the mass of the SMBH to over 10 10 M ⊙ . When allowance is made for momentum driving, the final SMBH mass is much lower and the wind efficiencies which lead to the most observationally acceptable results are relatively low with ǫ w 10 −4 .

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Beitr�ge zur Polarographie

Cited by 11 publications

References 0 publications

Neutral Gas Outflows and Inflows in Infrared-Faint Seyfert Galaxies

Neutral Gas Outflows and Inflows in Infrared-Faint Seyfert Galaxies

On the Feedback Efficiency of Active Galactic Nuclei

Momentum Driving: Which Physical Processes Dominate Active Galactic Nucleus Feedback?

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