中文
相关论文

相关论文: Small-area molecular clouds without shielding

200 篇论文

We are conducting COLD GASS, a legacy survey for molecular gas in nearby galaxies. Using the IRAM 30m telescope, we measure the CO(1-0) line in a sample of ~350 nearby (D=100-200 Mpc), massive galaxies (log(M*/Msun)>10.0). The sample is…

We aim at analysing systematically the distribution and physical properties of neutral and mildly ionised gas in the Milky Way halo, based on a large absorption-selected data set. Multi-wavelength studies were performed combining optical…

星系天体物理 · 物理学 2015-06-04 N. Ben Bekhti , B. Winkel , P. Richter , J. Kerp , U. Klein , M. T. Murphy

Recent submillimeter and far-infrared wavelength observations of absorption in the rotational ground-state lines of various simple molecules against distant Galactic continuum sources have opened the possibility of studying the chemistry of…

星系天体物理 · 物理学 2017-02-21 B. Winkel , H. Wiesemeyer , K. M. Menten , M. Sato , A. Brunthaler , F. Wyrowski , D. Neufeld , M. Gerin , N. Indriolo

Infrared dark clouds (IRDCs) are thought to be potential hosts of the elusive early phases of high-mass star formation. Here we conduct an in-depth kinematic analysis of one such IRDC, G034.43+00.24 (Cloud F), using high sensitivity and…

星系天体物理 · 物理学 2018-01-22 A. T. Barnes , J. D. Henshaw , P. Caselli , I. Jimenez-Serra , J. C. Tan , F. Fontani , A. Pon , S. Ragan

Our understanding of how molecular clouds form in the interstellar medium (ISM) would be greatly helped if we had a reliable observational tracer of the gas flows responsible for forming the clouds. Fine structure emission from singly…

星系天体物理 · 物理学 2019-05-14 Paul C. Clark , Simon C. O. Glover , Sarah E. Ragan , Ana Duarte-Cabral

The sample of 566 molecular clouds identified in the CO(2--1) IRAM survey covering the disk of M~33 is explored in detail.The clouds were found using CPROPS and were subsequently catalogued in terms of their star-forming properties as…

星系天体物理 · 物理学 2018-05-02 Jonathan Braine , Erik Rosolowsky , Pierre Gratier , Edvige Corbelli , Karl Schuster

We present an empirical dynamical model of the local interstellar medium based on 270 radial-velocity measurements for 157 sight lines toward nearby stars. Physical-parameter measurements (i.e., temperature, turbulent velocity, depletions)…

天体物理学 · 物理学 2007-09-28 Seth Redfield , Jeffrey L. Linsky

A set of HI sources extracted from the north Galactic polar region by the ongoing ALFALFA survey has properties that are consistent with the interpretation that they are associated with isolated minihalos in the outskirts of the Local Group…

宇宙学与河外天体物理 · 物理学 2015-05-14 Riccardo Giovanelli , Martha P. Haynes , Brian R. Kent , Elizabeth K. Adams

We have mapped cold atomic gas in 21cm line HI self-absorption (HISA) at arcminute resolution over more than 90% of the Milky Way's disk. To probe the formation of H2 clouds, we have compared our HISA distribution with CO J=1-0 line…

We apply gravity-based and density-based methods to identify clouds in numerical simulations of the star-forming, three-phase interstellar medium (ISM), and compare their properties and their global correlation with the star formation rate…

星系天体物理 · 物理学 2020-07-29 S. Alwin Mao , Eve C. Ostriker , Chang-Goo Kim

We combine data from our recent FUSE survey of interstellar molecular hydrogen absorption toward 50 high-latitude AGN with COBE-corrected IRAS 100 micron emission maps to study the correlation of infrared cirrus with H2. A plot of the H2…

天体物理学 · 物理学 2009-11-13 Kristen Gillmon , J. Michael Shull

The heliosphere serves as a probe of interstellar material (ISM) close to the Sun. Measurements of ISM inside and outside of the heliosphere show that we reside in typical warm partially ionized ISM that can be successfully modeled using…

天体物理学 · 物理学 2007-05-23 P. C. Frisch

We present BIMA observations of a 2$\arcmin$ field in the northeastern spiral arm of M31. In this region we find six giant molecular clouds that have a mean diameter of 57$\pm$13 pc, a mean velocity width of 6.5$\pm$1.2 \kms, and a mean…

天体物理学 · 物理学 2009-11-13 Kartik Sheth , Stuart N. Vogel , Christine D. Wilson , T. M. Dame

Observations show that the ISM contains sub-structure on scales less than 1 pc, detected in the form of spatial and temporal variations in column densities or optical depth. Despite the number of detections, the nature and ubiquity of the…

星系天体物理 · 物理学 2015-05-19 Soroush Nasoudi-Shoar , Philipp Richter , Klaas S. de Boer , Bart P. Wakker

Very sensitive 21cm HI measurements have been made at several locations around the Local Group galaxy M31 using the Green Bank Telescope (GBT) at an angular resolution of 9.1', with a 5$\sigma$ detection level of $\rm{N_{HI} = 3.9 \times…

星系天体物理 · 物理学 2016-01-27 Spencer A. Wolfe , Felix J. Lockman , D. J. Pisano

We present a 154 pointing IRAM NOEMA mosaic of the CO(1-0) line emission in and around the nearby starburst galaxy M82. The observations, complemented by zero--spacing observations, reach a spatial resolution of $\sim$30 pc ($\sim…

We present search results of 22 high latitude (b > 25 deg.) sightlines for OH 18-cm emission using the 305-m radio telescope at the Arecibo Observatory. These sightlines appear in neutral hydrogen emission at intermediate velocities (V_lsr…

星系天体物理 · 物理学 2023-05-10 Allison Smith , D. Anish Roshi

We report here the discovery of an apparent excess of 2MASS M giant candidates with dereddened 0.85 < J-K_S < 1.2 spanning a considerably large area of the celestial sphere between, at least, $100\degr < l < 150\degr$ and $-20\degr > b >…

We perform a systematic study of physical properties and distribution of neutral and ionised gas in the halo of the Milky Way (MW). Beside the large neutral intermediate- and high-velocity cloud (IVC, HVC) complexes there exists a…

星系天体物理 · 物理学 2010-07-21 N. Ben Bekhti , P. Richter , B. Winkel , J. Kerp , P. Kalberla , U. Klein , M. T. Murphy

Intermediate- and high-velocity clouds (IVCs, HVCs) are a potential source of fuel for star formation in the Milky Way (MW), but their origins and fates depend sensitively on their distances. We search for IVC and HVC in HST high-resolution…

星系天体物理 · 物理学 2022-04-20 N. Lehner , J. C. Howk , A. Marasco , F. Fraternali