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Related papers: W49A North - Global or Local or No Collapse?

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We recently proposed that molecular cloud dense cores undergo a prolonged period of quasi-static contraction prior to true collapse. This theory could explain the observation that many starless cores exhibit, through their spectral line…

Solar and Stellar Astrophysics · Physics 2015-05-19 Steven W. Stahler , Jeffrey J. Yen

Furukawa et al. 2009 reported the existence of a large mass of molecular gas associated with the super star cluster Westerlund 2 and the surrounding HII region RCW49, based on a strong morphological correspondence between NANTEN2…

The overwhelming evidence that the core collapse supernova mechanism is inherently multidimensional, the complexity of the physical processes involved, and the increasing evidence from simulations that the explosion is marginal presents…

The neutrino mechanism of core-collapse supernova is investigated via non-relativistic, two-dimensional (2D), neutrino radiation-hydrodynamic simulations. For the transport of electron flavor neutrinos, we use the interaction rates defined…

High Energy Astrophysical Phenomena · Physics 2016-01-27 Kuo-Chuan Pan , Matthias Liebendörfer , Matthias Hempel , Friedrich-Karl Thielemann

We have investigated the time scale for formation of molecular clouds by examining the conversion of HI to H2 using a time-dependent model. H2 formation on dust grains and cosmic ray and photo destruction are included in one-dimensional…

Astrophysics · Physics 2008-11-26 Paul F. Goldsmith , Di Li , Marko Krco

We present new two-dimensional (2D) axisymmetric neutrino radiation/hydrodynamic models of core-collapse supernova (CCSN) cores. We use the CASTRO code, which incorporates truly multi-dimensional, multi-group, flux-limited diffusion (MGFLD)…

Solar and Stellar Astrophysics · Physics 2015-06-19 Joshua C. Dolence , Adam Burrows , Weiqun Zhang

We report VLA HI Zeeman observations toward the W49A star-forming region and the SNR W49B. Line of sight magnetic fields (Blos) of 60 to 300 muG at 25" resolution were detected toward W49A at velocities of ~4 and ~7 km/s. The Blos values…

Astrophysics · Physics 2009-10-31 C. L. Brogan , T. H. Troland

We present in this paper the results of high spectral resolution ($R$=88,100) spectroscopy at 4.7 $\mu$m with iSHELL/IRTF of hot molecular gas close to the massive binary protostar W3 IRS5. The binary was spatially resolved and the spectra…

Astrophysics of Galaxies · Physics 2022-08-31 Jialu Li , Adwin Boogert , Andrew G. Barr , Alexander G. G. M. Tielens

A mapping observation of the $J=1/2$ $\Lambda$-type doubling transition (3.3 GHz) of CH has been conducted toward Heiles Cloud 2 (HCL2) in the Taurus molecular cloud complex to reveal its molecular cloud-scale distribution. The observations…

Solar and Stellar Astrophysics · Physics 2015-06-11 N. Sakai , H. Maezawa , T. Sakai , K. M. Menten , S. Yamamoto

To understand the formation process of massive stars, we present a multi-scale and multi-wavelength study of the W31 complex hosting two extended HII regions (i.e., G10.30-0.15 (hereafter, W31-N) and G10.15-0.34 (hereafter, W31-S)) powered…

Astrophysics of Galaxies · Physics 2022-07-27 A. K. Maity , L. K. Dewangan , H. Sano , K. Tachihara , Y. Fukui , N. K. Bhadari

We have observed 6 clouds along the line-of-sight toward W49A using the Submillimeter Wave Astronomy Satellite (SWAS) and several ground-based observatories. The ortho-H2O 1-0 and OH (1665 and 1667 MHz) transitions are observed in…

Spectral molecular line profile observations of star-forming molecular clouds sometimes show distinct red asymmetric double-peaked molecular line profiles with weaker blue peaks and stronger red peaks. For some star-forming molecular…

Solar and Stellar Astrophysics · Physics 2015-05-14 Yang Gao , Yu-Qing Lou

As a part of the Milky Way Imaging Scroll Painting (MWISP) survey, we performed a simultaneous 12CO(1-0), 13CO(1-0), C18O(1-0) mapping toward molecular clouds in a region encompassing 3.75 square degrees. We reveal three molecular clouds,…

Astrophysics of Galaxies · Physics 2016-03-30 Y. Gong , R. Q. Mao , M. Fang , S. B. Zhang , Y. Su , J. Yang , Z. B. Jiang , Y. Xu , M. Wang , Y. Wang , D. R. Lu , J. X. Sun

The C$_2$H $N=1-0$ transition was used to investigate the possible line of sight sub-structures from the dense and optically thick in $^{13}$CO $J=1-0$ regions in the Ophiuchus star forming molecular cloud. With a 0.2 K or lower noise,…

Astrophysics of Galaxies · Physics 2025-03-13 Lei qian , Zhichen Pan , Dongyue Jiang , Zichen Huang

We analyse column density and temperature maps derived from Herschel dust continuum observations of a sample of massive infrared dark clouds (G11.11-0.12, G18.82-0.28, G28.37+0.07, G28.53-0.25). We disentangle the velocity structure of the…

Astrophysics of Galaxies · Physics 2015-05-27 N. Schneider , T. Csengeri , R. S. Klessen , P. Tremblin , V. Ossenkopf , N. Peretto , R. Simon , S. Bontemps , C. Federrath

The construction of an accurate 3D model of the Milky Way center is necessary to understand inflow processes that drive its overall evolution, and to compare our Galactic nucleus to other galaxies' nuclei. A main point of contention is the…

We develop a semi-analytic model to explore the physical properties of cool pressure-confined circumgalactic clouds with mass ranging from $10$ to $10^{8} \, \rm M_{\odot}$ in a hot diffuse halo. We consider physical effects that control…

Astrophysics of Galaxies · Physics 2019-04-10 Ting-Wen Lan , Houjun Mo

The W49A star-forming region is embedded in a 10^6 solar mass molecular cloud, one of the most massive in our Galaxy. It has been long known as one of the most luminous radio HII regions, containing 30-40 compact and ultracompact HII…

Astrophysics · Physics 2007-05-23 N. L. Homeier , J. Alves

We present the results of a series of calculations studying the collapse of molecular cloud cores performed using a three-dimensional smoothed particle hydr odynamics code with radiative transfer in the flux-limited diffusion approximation.…

Astrophysics · Physics 2009-11-13 Stuart C. Whitehouse , Matthew R. Bate

Dynamically significant magnetic fields are routinely observed in molecular clouds, with mass-to-flux ratio lambda = (2 pi sqrt{G}) (Sigma/B) ~ 1 (here Sigma is the total column density and B is the field strength). It is widely believed…

Astrophysics · Physics 2009-11-13 Ruben Krasnopolsky , Charles F. Gammie