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Related papers: Disk stability under MONDian gravity

200 papers

We derive the projected surface mass distribution Sigma_M for spherically symmetric mass distributions having an arbitrary rotation curve. For a galaxy with a flat rotation curve and an ISM disk having a constant Toomre stability parameter,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Gerhardt R. Meurer , Zheng Zheng , W. J. G. de Blok

We show that the mass fraction f_atm = 1.35*MHI/M of neutral atomic gas (HI and He) in isolated local disk galaxies of baryonic mass M is well described by a straightforward stability model for flat exponential disks. In the outer disk…

Astrophysics of Galaxies · Physics 2016-06-22 Danail Obreschkow , Karl Glazebrook , Virginia Kilborn , Katharina Lutz

The majority of disk galaxies manifest spirals and/or bars that are believed to result from dynamical instabilities. However, some galaxies have featureless disks, which are therefore inferred to be dynamically stable. Yet despite many…

Astrophysics of Galaxies · Physics 2025-01-07 J A Sellwood , R G Carlberg

We investigate the stability of Milky Way analogs (MWAs) in the \texttt{TNG50} simulation against the growth of local axisymmetric instabilities, tracing their evolution from cosmic noon ($z=2.5$) to the present day ($z=0$). Using a…

Astrophysics of Galaxies · Physics 2026-01-28 K. Aditya , Sandeep Kataria

Regions of disc galaxies with widespread star formation tend to be both gravitationally unstable and self-shielded against ionizing radiation, whereas extended outer discs with little or no star formation tend to be stable and unshielded on…

In this work, we explore the cosmological stability of $f(Q, B)$ gravity using a dynamical system approach, where $Q$ denotes the nonmetricity scalar and $B$ represents the boundary term. We determine the model parameters of $f(Q, B)$…

General Relativity and Quantum Cosmology · Physics 2024-12-25 Santosh V. Lohakare , B. Mishra

Self-gravity becomes competitive as an angular momentum transport process in accretion discs at large radii, where the temperature is low enough that external irradiation likely contributes to the thermal balance. Irradiation is known to…

Solar and Stellar Astrophysics · Physics 2015-05-30 W. K. M. Rice , P. J. Armitage , G. R. Mamatsashvili , G. Lodato , C. J. Clarke

We study the deflection by gravity of a circular elastic disk deposited on a rigid support. The axisymmetric deflection induces a compressive orthoradial stresses which leads to a wrinkling instability above a critical threshold of the…

Soft Condensed Matter · Physics 2021-09-01 Gwenn Boedec , Julien Deschamps

We present a general star formation law where star formation rate depends upon efficiency $\alpha$, timescale $\tau$ of star formation, gas component $\sigma_{g}$ of surface mass density and a real exponent $n$. A given exponent $n$…

Astrophysics · Physics 2009-10-30 U. S. Pandey , C. van de Bruck

We analyze the cosmological solutions of $f(T,B)$ gravity using dynamical system analysis where $T$ is the torsion scalar and $B$ be the boundary term scalar. In our work, we assume two specific cosmological models. For first model, we…

General Relativity and Quantum Cosmology · Physics 2023-04-26 Amit Samaddar , S. Surendra Singh

Gravitational instabilities play a primary role in shaping the clumpy structure and powering the star formation activity of gas-rich high-redshift galaxies. Here we analyse the stability of such systems, focusing on the size and mass ranges…

Astrophysics of Galaxies · Physics 2015-06-19 Alessandro B. Romeo , Oscar Agertz

We present the effects of the self-gravity on the vertical structure and neutrino luminosity of the neutrino-dominated accretion disks in cylindrical coordinates. It is found that significant changes of the structure appear in the outer…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Tong Liu , Xiao-Fei Yu , Wei-Min Gu , Ju-Fu Lu

We develop several aspects of the theory of gaseous astrophysical discs in which the gravity of the disc makes a significant contribution to its structure and dynamics. We show how the internal gravitational potential can be expanded in…

Solar and Stellar Astrophysics · Physics 2025-03-18 Gordon I. Ogilvie

Using radiation hydrodynamics simulations in a local stratified shearing box with realistic equations of state and opacities, we explored the outcome of self-gravity at 50 AU in a protoplanetary disc irradiated by the central star. We found…

Earth and Planetary Astrophysics · Physics 2017-05-31 Shigenobu Hirose , Ji-Ming Shi

We address the cosmological evolution of violent gravitational instability in high-redshift, massive, star-forming galactic discs. To this aim, we integrate in time the equations of mass and energy conservation under self-regulated…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Marcello Cacciato , Avishai Dekel , Shy Genel

The present work is devoted to study the dynamical evolution of the galaxies in scalar-GaussBonnet gravity in relationship with the MOND paradigm. This study is useful for giving meaning to the presence of a new gravitational constant. The…

General Relativity and Quantum Cosmology · Physics 2022-01-19 M. Bousder

Accretion disks that become gravitationally unstable can fragment into stellar or sub-stellar companions. The formation and survival of these fragments depends on the precarious balance between self-gravity, internal pressure, tidal…

Solar and Stellar Astrophysics · Physics 2015-05-28 Kaitlin M. Kratter , Ruth A. Murray-Clay

In the dynamics of accretion disks, the presence of collective effects associated with the self-gravity of the disk is expected to affect not only the momentum transport, but also the relevant energy balance equations, which could differ…

Astrophysics · Physics 2009-11-06 G. Bertin , G. Lodato

Thermodynamical stability of fluid spheres is studied in the presence of a cosmological constant, both in the Newtonian limit, as well as in General Relativity. In all cases, an increase of the cosmological constant tends to stabilize the…

General Relativity and Quantum Cosmology · Physics 2013-05-22 Zacharias Roupas

The dynamical stability of disk galaxies is sensitive to whether their anomalous rotation curves are caused by dark matter halos or Milgromian Dynamics (MOND). We investigate this by setting up a MOND model of M33. We first simulate it in…

Astrophysics of Galaxies · Physics 2022-03-08 Indranil Banik , Ingo Thies , Graeme Candlish , Benoit Famaey , Rodrigo Ibata , Pavel Kroupa