English
Related papers

Related papers: Angular momentum and local gravitational instabili…

200 papers

We present the KMOS Galaxy Evolution Survey (KGES), a $K$-band Multi-Object Spectrograph (KMOS) study of the H$\alpha$ and [NII] emission from 288 $K$ band-selected galaxies at $1.2 \lesssim z \lesssim 1.8$, with stellar masses in the range…

We present new results on dynamical instabilities in rapidly rotating neutron-stars. In particular, using numerical simulations in full General Relativity, we analyse the effects that the stellar compactness has on the threshold for the…

Astrophysics · Physics 2008-11-26 G. M. Manca , L. Baiotti , R. De Pietri , L. Rezzolla

We consider the relationship between the total HI mass in late-type galaxies and the kinematic properties of their disks. The mass $M_HI$ for galaxies with a wide variety of properties, from dwarf dIrr galaxies with active star formation to…

Astrophysics · Physics 2009-11-11 A. V. Zasov , A. A. Smirnova

Evolutionary models of fast-rotating stars show that the stellar rotational velocity may approach the critical speed. Critically rotating stars cannot spin up more, therefore they lose their excess angular momentum through an equatorial…

Solar and Stellar Astrophysics · Physics 2014-12-10 Jiri Krticka , Petr Kurfurst , Iva Krtickova

The ergoregion instability is known to affect very compact objects that rotate very rapidly and do not possess a horizon. We present here a detailed analysis on the relevance of the ergoregion instability for the viability of gravastars.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Cecilia B. M. H. Chirenti , Luciano Rezzolla

Recent observations of the Class 0 protostar L1527 IRS have revealed a rotationally supported disc with an outer radius of at least 100 au. Measurements of the integrated flux at 870 microns suggest a disc mass that is too low for…

Solar and Stellar Astrophysics · Physics 2015-06-15 Duncan Forgan , Ken Rice

The Universe is pervaded by magnetic fields in different scales, although for simplicity, they are ignored in most cosmological simulations. In this paper, we use the TNG50, which is a large cosmological galaxy formation simulation that…

Astrophysics of Galaxies · Physics 2023-07-28 Mohammad Hosseinirad , Fatemeh Tabatabaei , Mojtaba Raouf , Mahmood Roshan

We study the global bending modes of a thin annular disc subject to both an internally generated magnetic field and a magnetic field due to a dipole embedded in the central star with axis aligned with the disc rotation axis. When there is a…

Astrophysics · Physics 2007-05-23 Vasso Agapitou , John C. B. Papaloizou , Caroline Terquem

Throughout the Hubble time, gas makes its way from the intergalactic medium into galaxies fuelling their star formation and promoting their growth. One of the key properties of the accreting gas is its angular momentum, which has profound…

Astrophysics of Galaxies · Physics 2020-03-04 Filippo Fraternali , Gabriele Pezzulli

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

We critically examine the theory of disk locking, which assumes that the angular momentum deposited on an accreting protostar is exactly removed by torques carried along magnetic field lines connecting the star to the disk. In this letter,…

Astrophysics · Physics 2009-11-10 Sean Matt , Ralph E. Pudritz

The effect of angular momentum on galaxy formation and evolution has been studied for several decades. Our recent two papers using IllustrisTNG-100 simulation have revealed the acquisition path of the angular momentum from large-scale…

Astrophysics of Galaxies · Physics 2023-12-01 Sen Wang , Dandan Xu , Shengdong Lu , Cheng Li

Galaxy formation models typically assume that the size and rotation speed of galaxy disks are largely dictated by the mass, concentration, and spin of their surrounding dark matter haloes. Equally important, however, are the fraction of…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-06 Laura V. Sales , Julio F. Navarro , Joop Schaye , Claudio Dalla Vecchia , Volker Springel , Marcel R. Haas , Amina Helmi

We show that the stellar surface-brightness profiles in disc galaxies---observed to be approximately exponential---can be explained if radial migration efficiently scrambles the individual stars' angular momenta while conserving the…

Astrophysics of Galaxies · Physics 2017-06-13 Jakob Herpich , Scott Tremaine , Hans-Walter Rix

We carry out three dimensional smoothed particle hydrodynamics simulations to study the impact of planet-disc interactions on a gravitationally unstable protoplanetary disc. We find that the impact of a planet on the disc's evolution can be…

Earth and Planetary Astrophysics · Physics 2022-11-01 Sahl Rowther , Rebecca Nealon , Farzana Meru

We performed 2D and full 3D magnetohydrodynamic simulations of disk accretion to a rotating star with an aligned or misaligned dipole magnetic field. We investigated the rotational equilibrium state and derived from simulations the ratio…

Gravitational instability is one of considerable mechanisms to explain the formation of giant planets. We study the gravitational stability for the protoplanetary disks around a protostar. The temperature and Toomre's Q-value are calculated…

Earth and Planetary Astrophysics · Physics 2019-03-18 Shigeo S. Kimura , Toru Tsuribe

We use the OWLS (OverWhelmingly Large Simulations) set of cosmological Nbody/gasdynamical simulations to study the properties of simulated galaxies at z=2. We focus on the effect of supernova feedback from evolving stars on the baryonic…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-25 Julio F. Navarro , Laura V. Sales , Joop Schaye , Claudio Dalla Vecchia , Volker Springel

We model the mass accretion rate $\dot{M}$ to stellar mass $M_*$ correlation that has been inferred from observations of intermediate to upper mass T Tauri stars---that is $\dot{M} \propto M_*^{1.3 \pm 0.3}$. We explain this correlation…

Solar and Stellar Astrophysics · Physics 2016-09-12 Alexander L. DeSouza , Shantanu Basu

We provide prescriptions to evaluate the dynamical mass ($M_{\rm dyn}$) of galaxies from kinematic measurements of stars or gas using analytic considerations and the VELA suite of cosmological zoom-in simulations at $z=1-5$. We find that…

Astrophysics of Galaxies · Physics 2021-07-07 Michael Kretschmer , Avishai Dekel , Jonathan Freundlich , Sharon Lapiner , Daniel Ceverino , Joel Primack