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Related papers: Testing Magnetic Star Formation Theory

200 papers

We investigate numerically the combined effects of supersonic turbulence, strong magnetic fields and ambipolar diffusion on cloud evolution leading to star formation. We find that, in clouds that are initially magnetically subcritical,…

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

We investigate the intrinsic shapes of starless cores in the Orion GMC, using the prestellar core sample of Nutter and Ward-Thompson (2007), which is based on submillimeter SCUBA data. We employ a maximum-likelihood method to reconstruct…

Astrophysics · Physics 2009-06-23 Konstantinos Tassis

A supersonic cloud-cloud collision produces a shock-compressed layer which leads to formation of high-mass stars via gravitational instability. We carried out a detailed analysis of the layer by using the numerical simulations of…

Astrophysics of Galaxies · Physics 2020-08-26 Yasuo Fukui , Tsuyoshi Inoue , Takahiro Hayakawa , Kazufumi Torii

The magnetic field strength in molecular clouds is a fundamental quantity for theories of star formation. It is estimated by Zeeman splitting measurements in a few dense molecular cores, but its volume--averaged value within large molecular…

Astrophysics · Physics 2009-11-10 Paolo Padoan , Raul Jimenez , Mika Juvela , Aake Nordlund

The angular momentum of a molecular cloud core plays a key role in star formation, since it is directly related to the outflow and the jet emanating from the new-born star and it eventually results in the formation of the protoplanetary…

Astrophysics of Galaxies · Physics 2019-08-14 Yoshiaki Misugi , Shu-ichiro Inutsuka , Doris Arzoumanian

We revisit the problem of the star formation timescale and the ages of molecular clouds. The apparent overabundance of star-forming molecular clouds over clouds without active star formation has been thought to indicate that molecular…

Astrophysics · Physics 2008-11-26 Telemachos Ch. Mouschovias , Konstantinos Tassis , Matthew W. Kunz

FU Ori is the prototype of FU Orionis systems which are outbursting protoplanetary disks. Magnetic fields in FU Ori's accretion disks have previously been detected using spectropolarimetry observations for Zeeman effects. We carry out…

Earth and Planetary Astrophysics · Physics 2020-04-15 Zhaohuan Zhu , Yan-Fei Jiang , James M. Stone

The influence of magnetic fields (B-fields) in the formation and evolution of bipolar bubbles, due to the expanding ionization fronts (I-fronts) driven by the Hii regions that are formed and embedded in filamentary molecular clouds, has not…

Molecular clouds are supported by turbulence and magnetic fields, but quantifying their influence on cloud lifecycle and star formation efficiency (SFE) remains an open question. We perform radiation MHD simulations of star-forming giant…

Astrophysics of Galaxies · Physics 2021-05-05 Jeong-Gyu Kim , Eve C. Ostriker , Nina Filippova

Filamentary structures are ubiquitously found in high-mass star-forming clouds. To investigate the relationship between filaments and star formation, we carry out the INFANT (INvestigations of massive Filaments ANd sTar formation) survey, a…

Observed protostellar outflows exhibit a variety of asymmetrical features, including remarkable unipolar outflows and bending outflows. Revealing the formation and early evolution of such asymmetrical protostellar outflows, especially the…

Solar and Stellar Astrophysics · Physics 2024-01-08 Daisuke Takaishi , Yusuke Tsukamoto , Miyu Kido , Shigehisa Takakuwa , Yoshiaki Misugi , Yuki Kudoh , Yasushi Suto

In the standard scenario of isolated low-mass star formation, strongly magnetized molecular clouds are envisioned to condense gradually into cores, driven by ambipolar diffusion. Once the cores become magnetically supercritical, they…

Astrophysics · Physics 2007-05-23 Fumitaka Nakamura , Zhi-Yun Li

Star formation takes place in filamentary molecular clouds which arise by physical processes that take place in the cold, neutral medium (CNM). We address the necessary conditions for this diffuse ($n \approx 30$ cm$^{-3}$), cold (T…

Astrophysics of Galaxies · Physics 2024-01-23 Rachel Pillsworth , Ralph E. Pudritz

Understanding star formation rates (SFR) is a central goal of modern star-formation models, which mainly involve gravity, turbulence and, in some cases, magnetic fields (B-fields). However, a connection between B-fields and SFR has never…

Astrophysics of Galaxies · Physics 2017-06-27 Hua-bai Li , Hangjin Jiang , Xiaodan Fan , Qilao Gu , Yapeng Zhang

We investigate differences in the molecular abundances between magnetically super- and sub-critical prestellar cores, performing three-dimensional non-ideal magnetohydrodynamical (MHD) simulations with varying densities and magnetic field…

Astrophysics of Galaxies · Physics 2019-07-17 Felix D. Priestley , James Wurster , Serena Viti

We have collated multiplicity data for five clusters (Taurus, Chamaeleon I, Ophiuchus, IC348, and the Orion Nebula Cluster). We have applied the same mass ratio (flux ratios of delta K <= 2.5) and primary mass cuts (~0.1-3.0 Msun) to each…

Solar and Stellar Astrophysics · Physics 2015-06-03 Robert R. King , Richard J. Parker , Jenny Patience , Simon P. Goodwin

Dense, star-forming, cores of molecular clouds are observed to be significantly magnetized. A realistic magnetic field of moderate strength has been shown to suppress, through catastrophic magnetic braking, the formation of a rotationally…

Astrophysics of Galaxies · Physics 2015-05-28 Zhi-Yun Li , Ruben Krasnopolsky , Hsien Shang

The stellar core formation and high speed jets driven by the formed core are studied by using three-dimensional resistive MHD nested grid simulations. Starting with a Bonnor-Ebert isothermal cloud rotating in a uniform magnetic field, we…

Astrophysics · Physics 2009-11-11 Masahiro N. Machida , Shu-ichiro Inutsuka , Tomoaki Matsumoto

On average molecular clouds convert only a small fraction epsilon_ff of their mass into stars per free-fall time, but differing star formation theories make contrasting claims for how this low mean efficiency is achieved. To test these…

Astrophysics of Galaxies · Physics 2022-02-09 Zipeng Hu , Mark R. Krumholz , Riwaj Pokhrel , Robert A. Gutermuth

We formulate the problem of the formation and subsequent evolution of fragments (or cores) in magnetically-supported, self-gravitating molecular clouds in two spatial dimensions. The six-fluid (neutrals, electrons, molecular and atomic…

Astrophysics · Physics 2011-02-11 Matthew W. Kunz , Telemachos Ch. Mouschovias