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Related papers: Testing Magnetic Star Formation Theory

200 papers

We present an analysis of polarised dust emission at 850 micron for a parsec long filament in the northern part of the Orion B molecular cloud. The region was observed by the JCMT SCUBA-2/POL-2 polarimeter. The filament has a line mass (~80…

We employ the three-dimensional magnetohydrodynamic simulation including ambipolar diffusion to study the gravitationally-driven fragmentation of subcritical molecular clouds, in which the gravitational fragmentation is stabilized as long…

Solar and Stellar Astrophysics · Physics 2015-05-20 Takahiro Kudoh , Shantanu Basu

We performed sub-parsec (~0.06pc) scale simulations of two idealised molecular clouds with different masses undergoing a collision. Gas clumps with density greater than 1e-20 g/cm3 (0.3e4 cm-3) were identified as pre-stellar cores and…

Astrophysics of Galaxies · Physics 2015-06-22 Ken Takahira , Elizabeth J. Tasker , Asao Habe

We study the polarization of the SiO maser emission in a representative sample of evolved stars in order to derive an estimate of the strength of the magnetic field, and thus determine the influence of this magnetic field on evolved stars.…

Astrophysics · Physics 2007-05-23 Fabrice Herpin , Alain Baudry , Clemens Thum , Dave Morris , Helmut Wiesemeyer

The dust emission polarization spectrum -- how the polarization percentage changes with wavelength -- serves as a probe of dust grain properties in star-forming regions. In this paper, we present 89 $\mu$m - 214 $\mu$m polarization spectrum…

Solar and Stellar Astrophysics · Physics 2025-09-18 Erin G. Cox , Giles Novak , David T. Chuss , Dennis Lee , Marc Berthoud , Kaitlyn Karpovich , Joseph M. Michail , Zhi-Yun Li , Peter C. Ashton

We numerically model evolution of magnetic fields inside a neutron star under the influence of ambipolar diffusion in the weak-coupling mode in the one-fluid MHD approximation. Our simulations are three-dimensional and performed in…

High Energy Astrophysical Phenomena · Physics 2022-11-09 Andrei P. Igoshev , Rainer Hollerbach

We present results from radiation non-ideal magnetohydrodynamics (MHD) calculations that follow the collapse of rotating, magnetised, molecular cloud cores to stellar densities. These are the first such calculations to include all three…

Solar and Stellar Astrophysics · Physics 2018-02-07 James Wurster , Matthew R. Bate , Daniel J. Price

Turbulence and magnetic fields are expected to be important for regulating molecular cloud formation and evolution. However, their effects on subparsec to 100 parsec scales, leading to the formation of starless cores, is not well…

The currently most viable methods to estimate magnetic field strengths in molecular cloud cores are Zeeman measurements and the Chandrasekhar-Fermi (CF) method. The CF-method estimates magnetic field strengths from polarimetry and relies on…

Astrophysics · Physics 2007-05-23 F. Heitsch , P. S. Li

We review theoretical models of the early stages of star formation, in which gravitational collapse is strongly regulated by magnetic fields and the associated process of ambipolar diffusion. We discuss results of numerical simulations and…

Astrophysics · Physics 2007-05-23 Glenn E. Ciolek , Shantanu Basu

The characterization of magnetic fields within molecular clouds is fundamental to understanding star formation processes. Accurately gauging the three-dimensional structure of these fields presents a challenge, as observational techniques…

Astrophysics of Galaxies · Physics 2024-11-18 Brandon Shane , Blakesley Burkhart , Laura Fissel , Susan E. Clark , Philip Mocz , Michael M. Foley

A comparison of accretion and (turbulent) magnetic diffusion timescales for sheets and filaments demonstrates that dense star-forming clouds generally will -- under realistic conditions -- become supercritical due to mass accretion on…

Astrophysics of Galaxies · Physics 2015-06-19 Fabian Heitsch , Lee Hartmann

We present submillimeter polarimetry at 850 micron toward the filamentary star-forming region associated with the reflection nebulosity NGC 2068 in Orion B. These data were obtained using the James Clerk Maxwell Telescope's SCUBA…

Astrophysics · Physics 2009-11-07 B. C. Matthews , C. D. Wilson

In the present study, the magnetic field scaling on density, $|B| \propto \rho^{\kappa}$, was revealed in a single starless core for the first time. The $\kappa$ index of $0.78 \pm 0.10$ was obtained toward the starless dense core FeSt…

We present the first interferometric polarization map of the W51 e1/e2 molecular cores obtained with the BIMA array at 1.3 mm wavelength with approximately 3 arcsecond resolution. The polarization angle varies smoothly across the double…

Astrophysics · Physics 2009-11-06 Shih-Ping Lai , Richard M. Crutcher , Jose M. Girart , Ramprasad Rao

The ratio of mass and magnetic flux determines the relative importance of magnetic and gravitational forces in the evolution of molecular clouds and their cores. Its measurement is thus central in discriminating between different theories…

Solar and Stellar Astrophysics · Physics 2015-06-22 K. Tassis , K. Willacy , H. W. Yorke , N. J. Turner

Stars are born in dense cores of molecular clouds. The core mass function (CMF), which is the mass distribution of dense cores, is important for understanding the stellar initial mass function (IMF). We obtained 350 $\mu$m dust continuum…

Solar and Stellar Astrophysics · Physics 2014-04-10 Guoyin Zhang , Di Li , Ashley K. Hyde , Lei Qian , Hualei Lyu , Zhongzu Wu

Magnetic fields of molecular clouds in the Central Molecular Zone (CMZ) have been relatively underobserved at sub-parsec resolution. Here we report JCMT/POL2 observations of polarized dust emission in the CMZ, which reveal magnetic field…

The role played by magnetic field during star formation is an important topic in astrophysics. We investigate the correlation between the orientation of star-forming cores (as defined by the core major axes) and ambient magnetic field…

We present a set of 3-dimensional, radiation-magnetohydrodynamic calculations of the gravitational collapse of massive (300 Msun), star-forming molecular cloud cores. We show that the combined effects of magnetic fields and radiative…

Solar and Stellar Astrophysics · Physics 2013-03-18 Andrew T. Myers , Christopher F. McKee , Andrew J. Cunningham , Richard I. Klein , Mark R. Krumholz
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