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Related papers: Some improvements to the spherical collapse model

200 papers

Dense cores inherit turbulent motions from the interstellar medium in which they form. As a tool for comparison to both simulations and observations, it is valuable to construct theoretical core models that can relate their internal density…

Astrophysics of Galaxies · Physics 2025-06-05 Sanghyuk Moon , Eve C. Ostriker

We studied the effects of cluster environments on galactic structures by using the TNG50 cosmological simulation and observed galaxies in the Fornax cluster. We focused on galaxies with stellar masses of $10^{8-12}M_{\odot}$ at z=0 that…

Over the last two decades, a large population of close-in planets has been detected around a wide variety of host stars. Such exoplanets are likely to undergo planetary migration through magnetic and tidal interactions. We aim to follow the…

Earth and Planetary Astrophysics · Physics 2021-06-23 Jérémy Ahuir , Antoine Strugarek , Allan-Sacha Brun , Stéphane Mathis

Recent observations of high-redshift supernovae seem to suggest that the global geometry of the Universe may be affected by a `cosmological constant', which acts to accelerate the expansion rate with time. But these data by themselves still…

Astrophysics · Physics 2009-10-31 Idit Zehavi , Avishai Dekel

Recent surveys show that protoplanetary disks have lower levels of turbulence than expected based on their observed accretion rates. A viable solution to this is that magnetized disk winds dominate angular momentum transport. This has…

Earth and Planetary Astrophysics · Physics 2022-08-17 Matthew Alessi , Ralph E. Pudritz

The most accurate method for modelling planetary migration and hence the formation of resonant systems is using hydrodynamical simulations. Usually, the force (torque) acting on a planet is calculated using the forces from the gas disc and…

Earth and Planetary Astrophysics · Physics 2020-04-08 S. Ataiee , W. Kley

Galaxy formation in the current cosmological paradigm is a very complex process in which inflows, outflows, interactions and mergers are common events. These processes can redistribute the angular momentum content of baryons. Recent…

Astrophysics of Galaxies · Physics 2015-08-31 Susana Pedrosa , Patricia Tissera

Recent developments suggested that planet formation occurs in regions of the discs with low turbulent viscosity. There, the dynamical corotation torque is thought to play an important role by slowing down type I migration. We aim to provide…

Earth and Planetary Astrophysics · Physics 2025-07-04 Jesse Weder , Clément Baruteau , Christoph Mordasini

We study dynamics of bars in models of disk galaxies embeded in realistic dark matter halos. We find that disk thickness plays an important, if not dominant, role in the evolution and structure of the bars. We also make extensive numerical…

Astrophysics · Physics 2015-05-13 A. Klypin , O. Valenzuela , P. Colin , T. Quinn

In the first paper we presented 27 hydrodynamical cosmological simulations of galaxies with total masses between $5 \times 10^8$ and $10^{10}\,\mathrm{M}_\odot$. In this second paper we use a subset of these cosmological simulations as…

Astrophysics of Galaxies · Physics 2017-11-08 Jonas Frings , Andrea V. Macciò , Tobias Buck , Camilla Penzo , Aaron A. Dutton , Aura Obreja , Marvin Blank

We compute the critical density of collapse for spherically symmetric overdensities in a class of f(R) modified gravity models. For the first time we evolve the Einstein, scalar field and non-linear fluid equations, making the minimal…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-26 Michael Kopp , Stephen A. Appleby , Ixandra Achitouv , Jochen Weller

We present a new theory for the hierarchical clustering of dark matter (DM) halos based on stochastic differential equations, that constitutes a change of perspective with respect to existing frameworks (e.g., the excursion set approach);…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-18 Andrea Lapi , Luigi Danese

The star formation rate (SFR), the number of stars formed per unit of time, is a fundamental quantity in the evolution of the Universe. While turbulence is believed to play a crucial role in setting the SFR, the exact mechanism remains…

Astrophysics of Galaxies · Physics 2024-10-02 Patrick Hennebelle , Noé Brucy , Tine Colman

Two mechanisms are considered responsible for the turbulence modification due to suspended particles in a turbulent gas-particle suspension. Turbulence augmentation is due to the enhancement of fluctuations by wakes behind particles,…

Fluid Dynamics · Physics 2018-11-19 V. Kumaran , P Muramalla , A. Tyagi , P. S. Goswami

In Meidt et al. (2018), we showed that gas kinematics on the scale of individual molecular clouds are not dominated by self-gravity but also track a component that originates with orbital motion in the potential of the host galaxy. This…

We generalize the spherical collapse model for the formation of dark matter halos to apply in a universe with arbitrary positive cosmological constant. We calculate the critical condition for collapse of an overdense region and give exact…

Astrophysics · Physics 2016-11-03 Ewa L. Lokas , Y. Hoffman

We present a new method to study the characteristic scales of collapse and fragmentation in galactic disks. Clump formation is seeded in simulations via controlled perturbations with a specified wavelength and velocity. These are applied to…

Astrophysics of Galaxies · Physics 2019-05-08 S. M. Benincasa , J. W. Wadsley , H. M. P. Couchman , A. R. Pettit , E. J. Tasker

I review the theory of angular momentum acquisition of galaxies by tidal torquing, the resulting angular momentum distribution, the angular momentum correlation function and discuss the implications of angular momentum alignments on weak…

Astrophysics · Physics 2013-03-07 Bjoern Malte Schaefer

We investigate the properties of the stellar populations of model galaxies as a function of galaxy evolutionary history and angular momentum content. We use the new semi-analytic model presented in Tonini et al. (2016). This new model…

Astrophysics of Galaxies · Physics 2017-01-11 Chiara Tonini , Simon J. Mutch , J. Stuart B. Wyithe , Darren J. Croton

Radial tidal forces can be compressive instead of disruptive, a possibility that is frequently overlooked in high level physics courses. For example, radial tidal compression can emerge in extended stellar systems containing a smaller…

Astrophysics · Physics 2009-06-23 Marco Masi