English
Related papers

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

200 papers

The cold neutral medium (CNM) is where neutral atomic hydrogen (HI) is converted into molecular clouds, so the structure and kinematics of the CNM are key drivers of galaxy evolution. Here we provide new constraints on the vertical…

Astrophysics of Galaxies · Physics 2024-09-30 Daniel R. Rybarczyk , Trey V. Wenger , Snezana Stanimirović

Galaxy disks are shown to contain a significant population of atomic clouds of 100pc linear size which are self-opaque in the 21cm transition. These objects have HI column densities as high as 10^23 and contribute to a global opacity…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Robert Braun

Radial density profiles for the sample of dense cores associated with high-mass star-forming regions from southern hemisphere have been derived using the data of observations in continuum at 250 GHz. Radial density profiles for the inner…

Astrophysics of Galaxies · Physics 2014-11-20 Lev E. Pirogov

A multitransitional study with the BIMA interferometric array was carried out toward the starless core found in the L673 region, in order to study the small-size structure of the cores detected with previous single--dish observations, which…

Astrophysics · Physics 2009-11-07 O. Morata , J. M. Girart , R. Estalella

The 23 GHz emission lines from the NH3 rotation inversion transitions are widely used to investigate the kinematics and physical conditions in dense molecular clouds. The line profile is composed of hyperfine components which can be used to…

Astrophysics · Physics 2009-11-07 Robeson S. McGary , Paul T. P. Ho

It is known that radial collapse around density peaks can explain the key features of evolution of correlation function in gravitational clustering in three dimensions. The same model also makes specific predictions for two dimensions. In…

Astrophysics · Physics 2009-10-30 J. S. Bagla , S. Engineer , T. Padmanabhan

Recent high-angular-resolution observations indicate the need for core growth to form high-mass stars. To understand the gas dynamics at the core scale in the very early evolutionary stages before being severely affected by feedback, we…

Astrophysics of Galaxies · Physics 2024-12-25 Kaho Morii , Patricio Sanhueza , Timea Csengeri , Fumitaka Nakamura , Sylvain Bontemps , Guido Garay , Qizhou Zhang

One of the longstanding issues in numerical relativity is to enable a simulation taking account of microphysical processes (e.g., weak interactions and neutrino cooling). We develop an approximate and explicit scheme in the fully general…

High Energy Astrophysical Phenomena · Physics 2010-12-09 Yuichiro Sekiguchi

We carried out synthetic observations of a theoretical model of interstellar carbon in CO, C I and C II including H2 formation. The theoretical model based on numerical simulations of H I gas converging at a velocity of 20 km/s by Inoue &…

Astrophysics of Galaxies · Physics 2018-11-07 Kengo Tachihara , Yasuo Fukui , Takahiro Hayakawa , Tsuyoshi Inoue

Core collapse is a prominent evolutionary stage of self-gravitating systems. In an idealised collisionless approximation, the region around the cluster core evolves in a self-similar way prior to the core collapse. Thus, its radial density…

Astrophysics of Galaxies · Physics 2018-12-05 Václav Pavlík , Ladislav Šubr

H$_{\rm I}$ 21-cm and $^{12}$CO 2.6-mm line emissions respectively trace the atomic and molecular gas phases, but they miss most of the opaque H$_{\rm I}$ and diffuse H$_2$ present in the Dark Neutral Medium (DNM) at the transition between…

High Energy Astrophysical Phenomena · Physics 2018-03-28 Q. Remy , I. A. Grenier , D. J. Marshall , J. M. Casandjian

We couple two-dimensional hydrodynamics to detailed one-dimensional multigroup flux-limited diffusion neutrino transport to investigate prompt convection in core collapse supernovae. Our initial conditions, time-dependent boundary…

We have observed the four hyperfine components of the 18 cm OH transition toward the translucent cloud eastward of Heiles Cloud 2 (HCL2E), the cold dark cloud L134N, and the photodissociation region of the $\rho$-Ophiuchi molecular cloud…

Astrophysics of Galaxies · Physics 2016-02-18 Yuji Ebisawa , Hiroshi Inokuma , Nami Sakai , Karl M. Menten , Hiroyuki Maezawa , Satoshi Yamamoto

The rotational transitions of carbon monoxide (CO) are the primary means of investigating the density and velocity structure of the molecular interstellar medium. Here we study the lowest four rotational transitions of CO towards…

Astrophysics · Physics 2009-10-31 James G. Ingalls , T. M. Bania , Adair P. Lane , Matthias Rumitz , Antony A. Stark

Constraining the physical and chemical evolution of molecular clouds is essential to our understanding of star formation. These investigations often necessitate knowledge of some local representative number density of the gas along the line…

Astrophysics of Galaxies · Physics 2025-04-02 Brandt A. L. Gaches , Michael Y. Grudić

Core-collapse supernova (SN) explosions may occur in the highly inhomogeneous molecular clouds (MCs) in which their progenitors were born. We perform a series of 3-dimensional hydrodynamic simulations to model the interaction between an…

High Energy Astrophysical Phenomena · Physics 2018-10-17 Dong Zhang , Roger A. Chevalier

We suggest that the high--velocity clouds (HVCs) are large clouds, with typical diameters of 25 kpc and containing 5e7 solar masses of neutral gas and 3e8 solar masses of dark matter, falling onto the Local Group; altogether the HVCs…

Astrophysics · Physics 2010-11-23 Leo Blitz , David N. Spergel , Peter J. Teuben , Dap Hartmann , W. Butler Burton

We propose a statistical tool to compare the scaling behaviour of turbulence in pairs of molecular cloud maps. Using artificial maps with well defined spatial properties, we calibrate the method and test its limitations to ultimately apply…

Solar and Stellar Astrophysics · Physics 2016-01-13 T. G. Arshakian , V. Ossenkopf

We attempt to visually classify the morphologies of 18190 molecular clouds, which are identified in the $^{12}$CO(1-0) spectral line data over $\sim$ 450 deg$^{2}$ of the second Galactic quadrant from the Milky Way Imaging Scroll Painting…

Astrophysics of Galaxies · Physics 2021-12-08 Lixia Yuan , Ji Yang , Fujun Du , Xunchuan Liu , Shaobo Zhang , Zehao Lin , Jingfei Sun , Qing-Zeng Yan , Yuehui Ma , Yang Su , Yan Sun , Xin Zhou

The global visibility of a singularity as an end state of the gravitational collapse of a spherically symmetric pressureless cloud is investigated. We show the existence of a non-zero measured set of parameters: the total mass and the…

General Relativity and Quantum Cosmology · Physics 2022-11-15 Karim Mosani , Dipanjan Dey , Pankaj S. Joshi
‹ Prev 1 8 9 10 Next ›