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Related papers: DR 21(OH): a highly fragmented, magnetized, turbul…

200 papers

We present high-angular-resolution ALMA (Atacama Large Millimeter Array) images of N$_{2}$H$^{+}$ (1--0) that has been combined with those from the Nobeyama telescope toward OMC-2 and OMC-3 filamentary regions. The filaments (with typical…

Astrophysics of Galaxies · Physics 2021-11-05 Xuefang Xu , Di Li , Y. Sophia Dai , Gary A. Fuller , Nannan Yue

We have performed 2D hydromagnetic simulations with an adaptive mesh refinement code to examine the response of a pre-existing initially spherical dense core to a non-linear fast-mode wave. One key parameter is the ratio of the wavelength…

Astrophysics · Physics 2008-11-26 S. Van Loo , S. A. E. G. Falle , T. W. Hartquist

The results of a near-infrared (J H K LP) imaging linear polarimetry survey of 20 young stellar objects (YSOs) in rho Ophiuchi are presented. The majority of the sources are unresolved, with K-band polarizations, P_K < 6 per cent. Several…

Astrophysics · Physics 2009-11-13 A. F. Beckford , P. W. Lucas , A. C. Chrysostomou , T. M. Gledhill

The early-type chemically peculiar stars often show strong magnetic fields on their surfaces. These magnetic topologies are organized on large scales and are believed to be close to an oblique dipole for most of the stars. In a striking…

Solar and Stellar Astrophysics · Physics 2015-05-20 Oleg Kochukhov , Andreas Lundin , Iosif Romanyuk , Dmitry Kudryavtsev

Light scattered off particles can become linearly polarized. Stars surrounded by oblique, co-rotating envelopes are therefore expected to manifest periodic linear polarimetric variations. The electron scattering magnetospheres of magnetic…

Solar and Stellar Astrophysics · Physics 2022-01-05 M. S. Munoz , G. A. Wade , D. M. Faes , A. C. Carciofi , J. Labadie-Bartz

Cha-MMS1 was mapped in the NH_3(1,1) line and the 1.2 cm continuum using the Australia Telescope Compact Array, ATCA. The angular resolution of the ATCA observations is 7'' (~ 1000 AU), and the velocity resolution is 50 m s^{-1}. The core…

Astrophysics of Galaxies · Physics 2017-05-26 M. S. Väisälä , J. Harju , M. J. Mantere , O. Miettinen , R. S. Sault , C. M. Walmsley , J. B. Whiteoak

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

We employ the first fully three-dimensional simulation to study the role of magnetic fields and ion-neutral friction in regulating gravitationally-driven fragmentation of molecular clouds. The cores in an initially subcritical cloud develop…

Astrophysics · Physics 2008-11-26 Takahiro Kudoh , Shantanu Basu , Youichi Ogata , Takashi Yabe

The role of magnetic fields in the early stages of star formation is not well constrained. In order to discriminate between different star formation models, we analyze 3D magnetohydrodynamic simulations of low-mass cores and explore the…

Astrophysics of Galaxies · Physics 2017-01-18 Joyce W. Y. Lee , Charles L. H. Hull , Stella S. R. Offner

We present broadband imaging polarimetry of DR21 at 2.2$\mu$m. Background stars shining through the lobes of the bipolar outflow show polarization aligned with the long axis of the outflow, indicating a magnetic field geometry oriented…

Astrophysics · Physics 2009-11-07 Terry Jay Jones , Hassib Amini

Sharp fronts observed by Chandra satellite between dense cool cluster cores moving with near-sonic velocity through the hotter intergalactic gas, require strong suppression of thermal conductivity across the boundary. This may be due to…

Astrophysics · Physics 2009-11-11 Maxim Lyutikov

Fragmentation is a key step in the process of transforming clouds (and their substructures such as filaments, clumps, and cores) into protostars. The thermal gas pressure and gravitational collapse are believed to be the primary agents…

Astrophysics of Galaxies · Physics 2023-06-21 Anirudh R. , Chakali Eswaraiah , Sihan Jiao , Jessy Jose

We report new, $\sim$1000 AU spatial resolution observations of 225 GHz dust continuum emission towards the OB cluster-forming molecular clump G33.92+0.11. On parsec scales, this molecular clump presents a morphology with several arm-like…

For a molecular cloud clump to form stars some transport of magnetic flux is required from the denser, inner regions to the outer regions of the cloud, otherwise this can prevent the collapse. Fast magnetic reconnection which takes place in…

High Energy Astrophysical Phenomena · Physics 2015-06-11 M. R. M. Leão , E. M. de Gouveia Dal Pino , R. Santos-Lima , A. Lazarian

Methods: We observed the high-mass hot core region G351.77-0.54 with ALMA and more than 16km baselines. Results: At a spatial resolution of 18/40au (depending on the distance), we identify twelve sub-structures within the inner few thousand…

Solar and Stellar Astrophysics · Physics 2019-01-16 H. Beuther , A. Ahmadi. J. C. Mottram , H. Linz , L. T. Maud , Th. Henning , R. Kuiper , A. J. Walsh , K. G. Johnston , S. N. Longmore

We have discovered 12 new molecular hydrogen emission-line objects (MHOs) in the vicinity of the candidate massive young stellar object Mol 121, in addition to five that were previously known. H2 2.12-micron/H2 2.25-micron flux ratios…

Astrophysics of Galaxies · Physics 2015-06-12 G. Wolf-Chase , K. Arvidsson , M. Smutko , R. Sherman

Thermal dust continuum polarimetry is a powerful indirect probe of magnetic field geometry in dense molecular clouds while at the same time providing information on the alignment of dust grains with the magnetic field. The leading theory of…

We present a detailed study of the Cep B molecular cloud based on sub-mm dust polarization and $^{13}$CO (J=3--2) spectral line observations obtained with SCUBA-2/POL-2 and HARP on the James Clerk Maxwell Telescope (JCMT). The 850 $\mu$m…

We present 850~$\mu$m linear polarization and C$^{18}$O~(3-2) and $^{13}$CO~(3-2) molecular line observations toward the filaments (F13 and F13S) in the Cocoon Nebula (IC~5146) using the JCMT POL-2 and HARP instruments. F13 and F13S are…

Astrophysics of Galaxies · Physics 2024-05-28 Eun Jung Chung , Chang Won Lee , Shinyoung Kim , Mario Tafalla , Hyunju Yoo , Jungyeon Cho , Woojin Kwon

Recent work by Mitra et al. (2014) has shown that in strongly stratified forced two-layer turbulence with helicity and corresponding large-scale dynamo action in the lower layer, a magnetic field occurs in the upper layer in the form of…

Solar and Stellar Astrophysics · Physics 2015-06-03 Sarah Jabbari , Axel Brandenburg , Nathan Kleeorin , Dhrubaditya Mitra , Igor Rogachevskii