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Related papers: Star Formation and the Hall Effect

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Stars form by the gravitational collapse of interstellar gas. The thermodynamic response of the gas can be characterized by an effective equation of state. It determines how gas heats up or cools as it gets compressed, and hence plays a key…

The formation of protostellar disks out of molecular cloud cores is still not fully understood. Under ideal MHD conditions, the removal of angular momentum from the disk progenitor by the typically embedded magnetic field may prevent the…

Astrophysics of Galaxies · Physics 2015-05-30 R. Santos-Lima , E. M. de Gouveia Dal Pino , A. Lazarian

Molecular clouds are prime locations to study the process of star formation. These clouds contain filamentary structures and cores, which are crucial sites for the formation of young stars. The star-formation process has been investigated…

Astrophysics of Galaxies · Physics 2024-03-01 Archana Soam , Chakali Eswaraiah , Amit Seta , Lokesh Dewangan , Maheswar G

The grand question of star and planet formation is the distribution of magnetic flux in the protoplanetary disks. To answer it, a detailed self-consistent chemical evolution is needed to describe the magnetic dissipation in the collapsing…

Solar and Stellar Astrophysics · Physics 2017-07-26 Natalia Dzyurkevich , Benoit Commercon , Pierre Lesaffre , Dimitry Semenov

In star formation, magnetic fields act as a cosmic angular momentum extractor that increases mass accretion rates onto protostars and in the process, creates spectacular outflows. However, recently it has been argued that this magnetic…

Solar and Stellar Astrophysics · Physics 2014-11-20 Dennis F. Duffin , Ralph E. Pudritz

The transport of angular momentum is capital during the formation of low-mass stars; too little removal and rotation ensures stellar densities are never reached, too much and the absence of rotation means no protoplanetary disks can form.…

Solar and Stellar Astrophysics · Physics 2018-07-04 Neil Vaytet , Benoît Commerçon , Jacques Masson , Matthias González , Gilles Chabrier

Star formation in our Galaxy occurs in molecular clouds that are self-gravitating, highly turbulent, and magnetized. We study the conditions under which cloud cores inherit large-scale magnetic field morphologies and how the field is…

Astrophysics of Galaxies · Physics 2017-03-29 Philip Mocz , Blakesley Burkhart , Lars Hernquist , Chris McKee , Volker Springel

Star forming molecular clouds are observed to be both highly magnetized and turbulent. Consequently the formation of protostellar disks is largely dependent on the complex interaction between gravity, magnetic fields, and turbulence.…

Astrophysics of Galaxies · Physics 2018-01-17 William J. Gray , Christopher F. McKee , Richard I. Klein

The Hall effect plays a significant role in star formation because it induces rotation in the infalling envelope, which in turn affects the formation and evolution of the circumstellar disk. The importance of the Hall effect varies with the…

Solar and Stellar Astrophysics · Physics 2019-01-09 Shunta Koga , Yusuke Tsukamoto , Satoshi Okuzumi , Masahiro N. Machida

Are the kG-strength magnetic fields observed in young stars a fossil field left over from their formation or are they generated by a dynamo? Our previous numerical study concluded that magnetic fields must originate by a dynamo process.…

Solar and Stellar Astrophysics · Physics 2022-01-20 James Wurster , Matthew R. Bate , Daniel J. Price , Ian A. Bonnell

The magnetic field of molecular clouds (MCs) plays an important role in the process of star formation: it determins the statistical properties of supersonic turbulence that controls the fragmentation of MCs, controls the angular momentum…

Astrophysics of Galaxies · Physics 2017-12-12 Paolo Padoan

In nearby star-forming clouds, amplification and dissipation of the magnetic field are known to play crucial roles in the star-formation process. The star-forming environment varies from place to place and era to era in galaxies. In the…

Solar and Stellar Astrophysics · Physics 2018-01-24 Koki Higuchi , Masahiro N. Machida , Hajime Susa

Strong magnetic fields play a crucial role in the removal of angular momentum from collapsing clouds and protostellar discs and are necessary for the formation of disc winds as well as jets from the inner disc and indeed, strong large-scale…

Solar and Stellar Astrophysics · Physics 2015-06-03 Jonathan Braithwaite

The efficiency of star formation, defined as the ratio of the stellar to total (gas and stellar) mass, is observed to vary from a few percent in regions of dispersed star formation to about a third in cluster-forming cores. This difference…

Astrophysics · Physics 2009-11-10 Fumitaka Nakamura , Zhi-Yun Li

We use magnetohydrodynamical simulations of converging flows to investigate the process of molecular cloud formation and evolution out of the magnetised ISM. Here, we investigate whether the observed subcritical HI clouds can become…

Astrophysics of Galaxies · Physics 2015-06-02 Bastian Körtgen , Robi Banerjee

Star formation is inefficient. Only a few percent of the available gas in molecular clouds forms stars, leading to the observed low star formation rate (SFR). The same holds when averaged over many molecular clouds, such that the SFR of…

Astrophysics of Galaxies · Physics 2016-06-13 Christoph Federrath

Massive stars disproportionately influence their surroundings. How they form has only started to become clear recently through radiation gas dynamical simulations. However, until now, no simulation has simultaneously included both magnetic…

Solar and Stellar Astrophysics · Physics 2015-03-17 Thomas Peters , Robi Banerjee , Ralf S. Klessen , Mordecai-Mark Mac Low

Stars form predominantly in clusters inside dense clumps of molecular clouds that are both turbulent and magnetized. The typical size and mass of the cluster-forming clumps are $\sim 1$ pc and $\sim 10^2 - $ 10$^3$ M$_\odot$, respectively.…

Astrophysics of Galaxies · Physics 2015-05-19 Fumitaka Nakamura , Zhi-Yun Li

The accretion phase of star formation is investigated in magnetically-dominated clouds that have an initial subcritical mass-to-flux ratio. We employ nonideal magnetohydrodynamic simulations that include ambipolar diffusion and ohmic…

Solar and Stellar Astrophysics · Physics 2020-03-18 Masahiro N. Machida , Shantanu Basu

Massive stars ($M > 8$ \msun) typically form in parsec-scale molecular clumps that collapse and fragment, leading to the birth of a cluster of stellar objects. We investigate the role of magnetic fields in this process through dust…