AGN Feedback in Elliptical Galaxies: Numerical Simulations

Ciotti, Luca; Ostriker, Jeremiah P.

doi:10.1007/978-1-4614-0580-1_4

Cited by 39 publications

(18 citation statements)

References 167 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At the end of the simulation, the cooled gas at the centre for this model is 1.8 × 10 10 M , while the ejected ISM is 7 × 10 9 M . If this model is allowed to have the accretion physics activated for the central black hole, we expect to recover the complex AGN feedback phenomena described elsewhere (Ciotti & Ostriker 2012), with significant reduction of the central accreted mass.…”

Section: The Eo7mentioning

confidence: 68%

See 1 more Smart Citation

The effects of galaxy shape and rotation on the X-ray haloes of early-type galaxies – II. Numerical simulations

Negri

Posacki

Pellegrini

et al. 2014

Monthly Notices of the Royal Astronomical Society

Self Cite

View full text Add to dashboard Cite

By means of high resolution 2D hydrodynamical simulations, we study the evolution of the hot ISM for a large set of early-type galaxy models, characterized by various degrees of flattening and internal rotation. The galaxies are described by state-of-the-art axisymmetric two-component models, tailored to reproduce real systems; the dark matter haloes follow the Navarro-Frenk-White or the Einasto profile. The gas is produced by the evolving stars, and heated by Type Ia SNe. We find that, in general, the rotation field of the ISM in rotating galaxies is very similar to that of the stars, with a consequent negligible heating contribution from thermalization of the ordered motions. The relative importance of flattening and rotation in determining the final X-ray luminosity L X and temperature T X of the hot haloes is a function of the galactic mass. Flattening and rotation in low mass galaxies favour the establishment of global winds, with the consequent reduction of L X . In medium-to-high mass galaxies, flattening and rotation are not sufficient to induce global winds, however, in the rotating models the nature of the gas flows is deeply affected by conservation of angular momentum, resulting in a reduction of both L X and T X .

show abstract

Section: The Eo7mentioning

confidence: 68%

“…From the point of view of the present investigation, the formation of stars, by reducing the amount of cold gas in the equatorial plane, could in principle also modify the evolution of the ISM. We performed a few tests where we activated star formation at a rateρ * , following Ciotti & Ostriker (2012) and references therein:…”

Section: Discussionmentioning

confidence: 99%

The effects of galaxy shape and rotation on the X-ray haloes of early-type galaxies – II. Numerical simulations

Negri

Posacki

Pellegrini

et al. 2014

Monthly Notices of the Royal Astronomical Society

Self Cite

View full text Add to dashboard Cite

show abstract

“…Ciotti & Ostriker 2012) or stellar thermal feedback (e.g. Stinson et al 2013) but also to the inability to cool their own coronal material experienced by massive galaxies (M vir > 3 × 10 12 M ).…”

Section: Implication For the Evolution Of Disc Galaxiesmentioning

confidence: 99%

Efficiency of gas cooling and accretion at the disc–corona interface

Armillotta

Fraternali

Marinacci

2016

Mon. Not. R. Astron. Soc.

142

136

View full text Add to dashboard Cite

In star-forming galaxies, stellar feedback can have a dual effect on the circumgalactic medium both suppressing and stimulating gas accretion. The trigger of gas accretion can be caused by disc material ejected into the halo in the form of fountain clouds and by its interaction with the surrounding hot corona. Indeed, at the disc-corona interface, the mixing between the cold/metal-rich disc gas (T 10 4 K) and the hot coronal gas (T 10 6 K) can dramatically reduce the cooling time of a portion of the corona and produce its condensation and accretion. We studied the interaction between fountain clouds and corona in different galactic environments through parsec-scale hydrodynamical simulations, including the presence of thermal conduction, a key mechanism that influences gas condensation. Our simulations showed that the coronal gas condensation strongly depends on the galactic environment, in particular it is less efficient for increasing virial temperature/mass of the haloes where galaxies reside and it is fully ineffective for objects with virial masses larger than 10 13 M . This result implies that the coronal gas cools down quickly in haloes with low-intermediate virial mass (M vir 3 × 10 12 M ) but the ability to cool the corona decreases going from late-type to earlytype disc galaxies, potentially leading to the switching off of accretion and the quenching of star formation in massive systems.

show abstract

“…Pre-heating instabilities that halt BH fueling already arise at Eddington ratios of ∼ 0.01 in the case of spherical accretion (Cowie et al 1978). Hydrodynamic simulations in 2D have shown that this also occurs when removing the constraint of spherical accretion (Novak et al 2011;Ciotti & Ostriker 2012). At high Eddington ratios an additional instability effect is expected to take place, due to a recurrent thickening of the accretion disc and the consequent increase of its covering factor.…”

Section: Introductionmentioning

confidence: 99%

Exponentially growing bubbles around early supermassive black holes

Gilli¹,

Calura²,

D’Ercole³

et al. 2017

A&A

View full text Add to dashboard Cite

We address the as yet unexplored issue of outflows induced by exponentially growing power sources, focusing on early supermassive black holes (BHs). We assumed that these objects grow to 10 9 M by z=6 by Eddington-limited accretion and convert 5% of their bolometric output into a wind. We first considered the case of energy-driven and momentum-driven outflows expanding in a region where the gas and total mass densities are uniform and equal to the average values in the Universe at z > 6. We derived analytic solutions for the evolution of the outflow: for an exponentially growing power with e-folding time t S al , we find that the late time expansion of the outflow radius is also exponential, with e-folding time of 5t S al and 4t S al in the energy-driven and momentum-driven limit, respectively. We then considered energy-driven outflows produced by quasi-stellar objects (QSOs) at the centre of early dark matter halos of different masses and powered by BHs growing from different seeds. We followed the evolution of the source power and of the gas and dark matter density profiles in the halos from the beginning of the accretion until z = 6. The final bubble radius and velocity do not depend on the seed BH mass, but are instead smaller for larger halo masses. At z=6, bubble radii in the range 50-180 kpc and velocities in the range 400-1000 km s −1 are expected for QSOs hosted by halos in the mass range 3 × 10 11 − 10 13 M . These radius and velocity scales compare well with those measured for the outflowing gas in the z=6.4 QSO SDSS J1148+5251. By the time the QSO is observed, we found that the total thermal energy injected within the bubble in the case of an energy-driven outflow is E th ∼ 5 × 10 60 erg. This is in excellent agreement with the value of E th = (6.2 ± 1.7) × 10 60 erg measured through the detection of the thermal Sunyaev-Zeldovich effect around a large population of luminous QSOs at lower redshifts. This suggests that QSO outflows are closer to the energy-driven limit than to the momentum-driven limit. We investigated the stability of the expanding gas shell in the case of an energy-driven supersonic outflow propagating within a dark matter halo with M h = 3 × 10 11 M at z=6. We found that the shell is Rayleigh-Taylor unstable already at early times and, by means of a simple model, we investigated the fate of the fragments detaching from the shell. We found that these fragments should rapidly evaporate because of the extremely high temperature of the hot gas bubble if this does not cool. Since the only effective cooling mechanism for such a gas is inverse Compton by the cosmic microwave background (CMB) photons (IC-CMB), which is important only at z ≥ 6, we speculate that such shell fragments may be observed only around high-z QSOs, where IC-CMB cooling of the bubble gas can prevent their evaporation.

show abstract

AGN Feedback in Elliptical Galaxies: Numerical Simulations

Cited by 39 publications

References 167 publications

The effects of galaxy shape and rotation on the X-ray haloes of early-type galaxies – II. Numerical simulations

The effects of galaxy shape and rotation on the X-ray haloes of early-type galaxies – II. Numerical simulations

Efficiency of gas cooling and accretion at the disc–corona interface

Exponentially growing bubbles around early supermassive black holes

Contact Info

Product

Resources

About