Parameter space studies for the self-gravity interfacial instability

Context. Saturn’s mid-sized moons (satellites) have a puzzling orbital configuration with trapping in mean-motion resonances with every-other pairs (Mimas-Tethys 4:2 and Enceladus-Dione 2:1). To reproduce their current orbital configuration on the basis of a recent model of satellite formation from a hypothetical ancient massive ring, adjacent pairs must pass first-order mean-motion resonances without being trapped. Aims. The trapping could be avoided by fast orbital migration and/or excitation of the satellite’s eccentricity caused by gravitational interactions between the satellites and the rings (the disk), which are still unknown. In our research we investigate the satellite orbital evolution due to interactions with the disk through full N-body simulations. Methods. We performed global high-resolution N-body simulations of a self-gravitating particle disk interacting with a single satellite. We used N ∼ 105 particles for the disk. Gravitational forces of all the particles and their inelastic collisions are taken into account. Results. Dense short-wavelength wake structure is created by the disk self-gravity and a few global spiral arms are induced by the satellite. The self-gravity wakes regulate the orbital evolution of the satellite, which has been considered as a disk spreading mechanism, but not as a driver for the orbital evolution. Conclusions. The self-gravity wake torque to the satellite is so effective that the satellite migration is much faster than was predicted with the spiral arm torque. It provides a possible model to avoid the resonance capture of adjacent satellite pairs and establish the current orbital configuration of Saturn’s mid-sized satellites.

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The Effect of the Self‐Gravity of Gas on Gas Fueling in a Barred Galaxy with a Supermassive Black Hole

The Astrophysical Journal ◽

10.1086/308233 ◽

2000 ◽

Vol 529 (1) ◽

pp. 109-118 ◽

Cited By ~ 28

Author(s):

Hiroyuki Fukuda ◽

Asao Habe ◽

Keiichi Wada

Keyword(s):

Black Hole ◽

The Self ◽

Supermassive Black Hole ◽

Self Gravity

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11.15. The effect of a central massive black hole on the gas fueling

Symposium - International Astronomical Union ◽

10.1017/s0074180900085697 ◽

1998 ◽

Vol 184 ◽

pp. 485-486

Author(s):

H. Fukuda ◽

A. Habe ◽

K. Wada

Keyword(s):

Black Hole ◽

Numerical Simulations ◽

Gravitational Potential ◽

Galactic Center ◽

The Self ◽

Massive Black Hole ◽

Nuclear Regions ◽

Self Gravity ◽

Lindblad Resonance ◽

Inner Lindblad Resonance

Nuclear activities in galaxies, such as nuclear starbursts or AGNs, are supposed to be induced by gas fueling into nuclear regions of galaxies. Non-axisymmetric gravitational potential caused by a stellar bar is a convincing mechanism for triggering gas fueling (Phinney 1994). However, numerical simulations have shown that the bar can not force the gas to accrete toward the galactic center beyond the inner Lindblad resonance (ILR). As a mechanism to overcome the ILR barrier, the double barred structure (Friedli & Martinet 1993), or the self-gravity of gas (Wada & Habe 1992, 1995; Elmegreen 1994) are proposed.

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Models for the dynamics of dust-like matter in the self-gravity field: The method of hydrodynamic substitutions

Journal of Experimental and Theoretical Physics ◽

10.1134/s1063776117090102 ◽

2017 ◽

Vol 125 (3) ◽

pp. 420-433

Author(s):

V. M. Zhuravlev

Keyword(s):

Gravity Field ◽

The Self ◽

Self Gravity

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Hydrodynamical simulations of the barred spiral galaxy NGC 1097

Proceedings of the International Astronomical Union ◽

10.1017/s174392131401148x ◽

2012 ◽

Vol 10 (H16) ◽

pp. 376-376

Author(s):

Lien-Hsuan Lin ◽

Hsiang-Hsu Wang ◽

Pei-Ying Hsieh ◽

Ronald E. Taam ◽

Chao-Chin Yang ◽

...

Keyword(s):

Spiral Galaxy ◽

Gas Flow ◽

Elliptical Galaxy ◽

The Self ◽

Two Dimensional ◽

Nuclear Ring ◽

Barred Spiral Galaxy ◽

Circumnuclear Disk ◽

Hydrodynamical Simulations ◽

Self Gravity

AbstractNGC 1097 is a nearby barred spiral galaxy believed to be interacting with the elliptical galaxy NGC 1097A located to its northwest. It hosts a Seyfert 1 nucleus surrounded by a circumnuclear starburst ring. Two straight dust lanes connected to the ring extend almost continuously out to the bar. The other ends of the dust lanes attach to two main spiral arms. To provide a physical understanding of its structural and kinematical properties, two-dimensional hydrodynamical simulations have been carried out. Numerical calculations reveal that many features of the gas morphology and kinematics can be reproduced provided that the gas flow is governed by a gravitational potential associated with a slowly rotating strong bar. By including the self-gravity of the gas disk in our calculation, we have found the starburst ring to be gravitationally unstable which is consistent with the observation in Hsieh et al. (2011). Our simulations also show that gas can flow into the region within the starburst ring even after its formation, leading to the coexistence of both a nuclear ring and a circumnuclear disk.

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Do Spiral Galaxies have a Variable Disk Thickness?

Symposium - International Astronomical Union ◽

10.1017/s0074180900032460 ◽

1983 ◽

Vol 100 ◽

pp. 77-79

Author(s):

Kristen Rohlfs

Keyword(s):

Spiral Galaxies ◽

Good Description ◽

The Self ◽

Disk Thickness ◽

Self Consistent ◽

Image Position ◽

External Forces ◽

Self Gravity

Estimating the forces in the z-direction that affect the disks of spiral galaxies in reasonable galactic mass models we find (Rohlfs and Kreitschmann 1981) that all external forces are small compared to the self-gravity of the disk so that Spitzer's (1942) self-consistent sheet model should give a good description for the z-distribution of the disk where it is well visible. But then the three parameters describing this shape are connected by the formula

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Dynamics of eccentric and inclined ringlets

International Astronomical Union Colloquium ◽

10.1017/s0252921100101381 ◽

1984 ◽

Vol 75 ◽

pp. 341-343

Author(s):

N. Borderies ◽

P. Goldreich ◽

S. Tremaine

Keyword(s):

Semimajor Axis ◽

Ring System ◽

The Self ◽

Uranian Ring ◽

Self Gravity

The Saturn and Uranian ring system contain a number of narrow eccentric ringlets. Several of the Uranian ringlets are also inclined to the planet's equator. We show that the self-gravity is probably responsible for maintaining apse and node alignment across these ringlets. This hypothesis leads to the prediction that within each ringlet both the eccentricity and the inclination increase with semimajor axis.

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