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Magnetic fields play a vital role in numerous astrophysical processes such as star formation and the interstellar medium. In particular, their role in the formation and evolution of galaxies is not well understood. This paper presents…

Astrophysics of Galaxies · Physics 2021-12-10 Huai-Hsuan Chiu , Ke-Jung Chen

In the present-day universe, magnetic fields play such essential roles in star formation as angular momentum transport and outflow driving, which control circumstellar disc formation/fragmentation and also the star formation efficiency.…

Astrophysics of Galaxies · Physics 2022-12-28 Kenji Eric Sadanari , Kazuyuki Omukai , Kazuyuki Sugimura , Tomoaki Matsumoto , Kengo Tomida

We examine the effect of magnetic fields on star cluster formation by performing simulations following the self-gravitating collapse of a turbulent molecular cloud to form stars in ideal MHD. The collapse of the cloud is computed for global…

Astrophysics · Physics 2009-11-13 Daniel Price , Matthew Bate

The question whether magnetic fields play an important role in the processes of molecular cloud and star formation has been debated for decades. Recent observations have revealed a simple picture that may help illuminate these questions:…

Astrophysics of Galaxies · Physics 2015-06-19 Hua-bai Li , Alyssa Goodman , T. K. Sridharan , Martin Houde , Zhi-Yun Li , Giles Novak , Kwok Sun Tang

We study the implications of primordial magnetic fields for the thermal and ionization history of the post-recombination era. In particular we compute the effects of dissipation of primordial magnetic fields owing to ambipolar diffusion and…

Astrophysics · Physics 2009-11-13 Shiv K Sethi , Biman B. Nath , Kandaswamy Subramanian

We calculate the ionisation fraction in protostellar disk models using a number of different chemical reaction networks, including gas-phase and gas-grain reaction schemes. The disk models we consider are conventional alpha-disks, which…

Astrophysics · Physics 2009-11-11 Martin Ilgner , Richard P. Nelson

Dust polarization observational results are analyzed for the high-mass star formation region W51 from the largest parent cloud ($\sim$ 2~pc, JCMT) to the large-scale envelope ($\sim$ 0.5~pc, BIMA) down to the collapsing core e2 ($\sim$…

Astrophysics of Galaxies · Physics 2015-06-03 Patrick M. Koch , Ya-Wen Tang , Paul T. P. Ho

Magnetic fields are ubiquitously observed in the interstellar medium (ISM) of present-day star-forming galaxies with dynamically relevant energy densities. Using three-dimensional magneto-hydrodynamic (MHD) simulations of the supernova (SN)…

Cosmic rays (CR) play an important role in dense molecular cores, affecting their thermal and dynamical evolution and initiating the chemistry. Several studies have shown that the formation of protostellar discs in collapsing clouds is…

Astrophysics of Galaxies · Physics 2015-06-17 Marco Padovani , Patrick Hennebelle , Daniele Galli

We investigate the effects of magnetic fields and radiative protostellar feedback on the star formation process using self-gravitating radiation magnetohydrodynamical calculations. We present results from a series of calculations of the…

Solar and Stellar Astrophysics · Physics 2015-05-13 Daniel J. Price , Matthew R. Bate

Are magnetic fields important in primordial star formation? Assuming that star formation occurs via an accretion disk that is turbulent, initially because of local gravitational instability, we calculate the disk structure for realistic…

Astrophysics · Physics 2009-11-10 Jonathan C. Tan , Eric G. Blackman

The configuration and evolution of the magnetic field in star-forming cores are investigated in order to directly compare simulations and observations. We prepare four different initial clouds having different magnetic field strengths and…

Solar and Stellar Astrophysics · Physics 2015-06-11 Akimasa Kataoka , Masahiro N. Machida , Kohji Tomisaka

Magnetic fields are important at every scale in the star formation process: from the dynamics of the ISM in galaxies, to the collapse of turbulent molecular clouds to form stars and in the fragmentation of individual star forming cores. The…

Astrophysics · Physics 2008-04-30 Daniel J. Price , Matthew R. Bate , Clare L. Dobbs

While magnetic fields are important in contemporary star formation, their role in primordial star formation is unknown. Magnetic fields of order 10^-16 G are produced by the Biermann battery due to the curved shocks and turbulence…

Astrophysics of Galaxies · Physics 2020-07-15 Christopher F. McKee , Athena Stacy , Pak Shing Li

Molecular clouds interacting with supernova remnants may be subject to a greatly enhanced irradiation by cosmic rays produced at the shocked interface between the ejecta and the molecular gas. Over the past decade, broad-band observations…

Astrophysics · Physics 2009-11-11 M. Fatuzzo , F. C. Adams , F. Melia

We present our current understanding of the formation and early evolution of protostars, protoplanetary disks, and the driving of outflows as dictated by the interplay of magnetic fields and partially ionized gas in molecular cloud cores.…

Solar and Stellar Astrophysics · Physics 2022-09-29 Yusuke Tsukamoto , Anaëlle Maury , Benoît Commerçon , Felipe O. Alves , Erin G. Cox , Nami Sakai , Tom Ray , Bo Zhao , Masahiro N. Machida

Understanding the physics of how stars form is a highly-prioritized goal of modern Astrophysics, in part because star formation is linked to both galactic dynamics on large scales and to the formation of planets on small scales. It is…

Requirements for magnetic coupling and accretion in the active layer of a protostellar disk are re-examined, and some implications for thermal emission from the layer are discussed. The ionization and electrical conductivity are calculated…

Solar and Stellar Astrophysics · Physics 2009-08-05 Xue-Ning Bai , Jeremy Goodman

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 magnetic field is a key ingredient in the recipe of star formation. Over the past two decades, millimeter and submillimeter interferometers have made major strides in unveiling the role of the magnetic field in star formation at…

Solar and Stellar Astrophysics · Physics 2019-03-11 Charles L. H. Hull , Qizhou Zhang