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Related papers: Impeding Turbulence Decay in Self-gravitating Clou…

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We study the dynamical state of cores by using a simple analytical model, a sample of observational massive cores, and numerical simulations of collapsing massive cores. From the model, we find that, if cores are formed from turbulent…

Astrophysics of Galaxies · Physics 2018-06-27 Javier Ballesteros-Paredes , Enrique Vázquez-Semadeni , Aina Palau , Ralf S. Klessen

Supersonic turbulence plays a pivotal role during the formation of molecular clouds and stars in galaxies. However, little is known about how the fraction of compressive and solenoidal modes in the velocity field evolves over time and how…

Astrophysics of Galaxies · Physics 2020-07-29 Bastian Körtgen

Observations of molecular structures on scales of $\sim 0.1-50$ pc show that the specific angular momentum ($j$) scales with radius ($R$) as $j\sim R^{3/2}$. We study the effects of turbulence, gravity, and the magnetic field in shaping…

Astrophysics of Galaxies · Physics 2026-04-22 Griselda Arroyo-Chavez , Enrique Vazquez-Semadeni , James Wurster

Self-gravity and stellar feedback are capable of driving turbulence and transporting mass and angular momentum in disk galaxies, but the balance between them is not well understood. In the previous paper in this series, we showed that…

Astrophysics of Galaxies · Physics 2016-08-17 Nathan J. Goldbaum , Mark R. Krumholz , John C. Forbes

In this paper, we review some of the properties of dense molecular cloud cores. The results presented here rely on three-dimensional numerical simulations of isothermal, magnetized, turbulent, and self-gravitating molecular clouds (MCs) in…

Astrophysics · Physics 2008-08-29 Sami Dib , Roberto Galvan-Madrid , Jongsoo Kim , Enrique Vazquez-Semadeni

We study turbulent dissipation in the ISM and explore some implications for galaxy formation and evolution using 2D MHD numerical simulations of compressible fluids. The turbulent kinetic energy E_k is injected by stellar sources formed…

Astrophysics · Physics 2007-05-23 V. Avila-Reese , E. Vázquez-Semadeni

Gravity drives the collapse of molecular clouds through which stars form, yet the exact role of gravity in cloud collapse remains a complex issue. Studies point to a picture where star formation occurs in clusters. In a typical, pc-sized…

Astrophysics of Galaxies · Physics 2023-11-07 Guang-Xing Li

We discuss HD and MHD compressible turbulence as a cloud-forming and cloud-structuring mechanism in the ISM. Results from a numerical model of the turbulent ISM at large scales suggest that the phase-like appearance of the medium, the…

Astrophysics · Physics 2007-05-23 Enrique Vazquez-Semadeni

Turbulence is a key ingredient for the evolution of the intracluster medium, whose properties can be predicted with high resolution numerical simulations. We present initial results on the generation of solenoidal and compressive turbulence…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 F. Vazza , T. W. Jones , M. Brüggen , G. Brunetti , C. Gheller , D. Porter , D. Ryu

Star formation is primarily controlled by the interplay between gravity, turbulence, and magnetic fields. However, the turbulence and magnetic fields in molecular clouds near the Galactic Center may differ substantially from spiral-arm…

The interstellar medium (ISM) is ubiquitously turbulent across many physically distinct environments within the Galaxy. Turbulence is key in controlling the structure and dynamics of the ISM, regulating star formation, and transporting…

Supersonic turbulence plays a dual role in molecular clouds: On one hand, it contributes to the global support of the clouds, while on the other it promotes the formation of small-scale density fluctuations, identifiable with clumps and…

Astrophysics · Physics 2015-11-11 Enrique Vazquez-Semadeni

Dense cores, the progenitors of stars, are in sub-pc scale and fragmented from pc-scale clumps. However, it is still unclear that how strongly the fragmentation process is affected by the properties of the host clumps, and how these…

Astrophysics of Galaxies · Physics 2025-12-11 Wei-An Chen , Seamus D. Clarke , Ya-Wen Tang

The dense molecular cloud cores that form stars, like other self-gravitating objects, undergo bulk oscillations. Just at the point of gravitational instability, their fundamental oscillation mode has zero frequency. We study, using…

Solar and Stellar Astrophysics · Physics 2009-11-13 Steven W. Stahler , Jeffrey J. Yen

We present the results of a numerical simulation in which star formation proceeds from an initially unbound molecular cloud core. The turbulent motions, which dominate the dynamics, dissipate in shocks leaving a quiescent region which…

Astrophysics · Physics 2009-11-10 Paul C. Clark , Ian A. Bonnell

Complex turbulent motions of magnetized gas are ubiquitous in the interstellar medium. The source of this turbulence, however, is still poorly understood. Previous work suggests that compression caused by supernova shockwaves, gravity, or…

Astrophysics of Galaxies · Physics 2020-02-26 Ankush Mandal , Christoph Federrath , Bastian Körtgen

Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass from the surrounding cloud material. Molecular cloud regions without turbulent driving sources, or where turbulence is driven…

Astrophysics · Physics 2009-11-06 Ralf Klessen

Abundant observational evidence indicates that the cooling time t_cool of the hot ambient medium pervading a massive galaxy does not drop much below 10 times the freefall time t_ff at any radius. Theoretical models have accounted for this…

Astrophysics of Galaxies · Physics 2018-12-05 G. M. Voit

Low mass, self-gravitating accretion disks admit quasi-steady,`gravito-turbulent' states in which cooling balances turbulent viscous heating. However, numerical simulations show that gravito-turbulence cannot be sustained beyond dynamical…

Earth and Planetary Astrophysics · Physics 2016-06-22 Min-Kai Lin , Kaitlin M. Kratter

I discuss the role of self-gravity and radiative heating and cooling in shaping the nature of the turbulence in the interstellar medium (ISM) of our galaxy. The heating and cooling cause it to be highly compressible, and, in some regimes of…

Astrophysics of Galaxies · Physics 2012-02-22 Enrique Vazquez-Semadeni