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Related papers: Diffuse Molecular Cloud Densities from UV Measurem…

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(Abridged) We carried out a comprehensive far-ultraviolet (UV) survey of ^12CO and H_2 column densities along diffuse molecular Galactic sight lines in order to explore in detail the relationship between CO and H_2. We measured new CO…

Astrophysics · Physics 2009-11-13 Y. Sheffer , M. Rogers , S. R. Federman , N. P. Abel , R. Gredel , D. L. Lambert , G. Shaw

In this work, we report a study on the relationship between flux and intensity for molecular clouds. Our analysis is established on high-quality CO images from the Milky Way Imaging Scroll Painting (MWISP) project. The new flux-intensity…

Astrophysics of Galaxies · Physics 2024-06-13 Qing-Zeng Yan , Ji Yang , Yang Su , Yan Sun , Shaobo Zhang , Xin Zhou , Chen Wang , Yiping Ao , Xuepeng Chen , Min Wang

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…

Astrophysics of Galaxies · Physics 2017-02-21 B. Winkel , H. Wiesemeyer , K. M. Menten , M. Sato , A. Brunthaler , F. Wyrowski , D. Neufeld , M. Gerin , N. Indriolo

New and archival interferometric 12CO(1->0) datasets from six nearby galaxies are combined with H_2 2.122um and H-alpha maps to explore in detail the interstellar medium in different star-forming galaxies. We investigate the relation…

A longstanding problem in astrochemistry is how molecules can be maintained in the gas phase in dense inter- and circumstellar regions. Photodesorption is a non-thermal desorption mechanism, which may explain the small amounts of observed…

Astrophysics · Physics 2015-05-13 Karin I. Oberg , Ewine F. van Dishoeck , Harold Linnartz

High quality archival spectra of interstellar absorption from C I toward 9 stars, taken with the Goddard High Resolution Spectrograph on the Hubble Space Telescope, were analyzed. Our sample was supplemented by two sight lines, 23 Ori and…

Astrophysics · Physics 2009-11-07 J. Zsargo , S. R. Federman

The mobility of atoms, molecules and radicals in icy grain mantles regulate ice restructuring, desorption, and chemistry in astrophysical environments. Interstellar ices are dominated by H2O, and diffusion on external and internal (pore)…

Far Ultraviolet Spectroscopic Explorer (FUSE) data is used to investigate the molecular hydrogen (H_2) content of intermediate-velocity clouds (IVCs) in the lower halo of the Milky Way. We analyze interstellar absorption towards 56 (mostly…

Astrophysics · Physics 2009-11-07 P. Richter , B. P. Wakker , B. D. Savage , K. R. Sembach

Gravitational accretion accumulates the original mass, and this process is crucial for us to understand the initial phases of star formation. Using the specific infall profiles in optically thick and thin lines, we searched the clumps with…

Astrophysics of Galaxies · Physics 2020-09-02 Yang Yang , Zhibo Jiang , Zhiwei Chen , Shaobo Zhang , Shuling Yu , Yiping Ao

We report results from a FUSE survey of interstellar molecular hydrogen (H2) along 45 sight lines to AGN at high Galactic latitudes (|b| > 20 degrees). Most (39 of 45) of the sight lines show detectable Galactic H2 absorption from Lyman and…

Astrophysics · Physics 2009-11-13 Kristen Gillmon , J. Michael Shull , Jason Tumlinson , Charles Danforth

The $^{13}$CO molecule is often used as a column density tracer in regions where the $^{12}$CO emission saturates. The $^{13}$CO column density is then related to that of $^{12}$CO by a uniform isotopic ratio. A similar approximation is…

Astrophysics of Galaxies · Physics 2016-04-25 László Szűcs , Simon C. O. Glover , Ralf S. Klessen

We model the intensity of emission lines from the CO molecule, based on hydrodynamic simulations of spirals, mergers, and high-redshift galaxies with very high resolutions (3pc and 10^3 Msun) and detailed models for the phase-space…

Astrophysics of Galaxies · Physics 2015-02-25 F. Bournaud , E. Daddi , A. Weiss , F. Renaud , C. Mastropietro , R. Teyssier

We have detected the J=4-3 rotational transition of 12CO in absorption at z=0.89 towards the quasar PKS1830-211, but not the 12CO 5-4 or the 3P1-3P0 fine structure line of neutral carbon. The intervening molecular medium thus has a total…

Astrophysics · Physics 2009-10-30 M. Gerin , T. G. Phillips , D. J. Benford , K. H. Young , K. M. Menten , B. Frye

The aim of this study is to investigate systematic chemical differentiation of molecules in regions of high mass star formation. We observed five prominent sites of high mass star formation in HCN, HNC, HCO+, their isotopes, C18O, C34S and…

Astrophysics of Galaxies · Physics 2010-11-02 I. Zinchenko , P. Caselli , L. Pirogov

We mapped the kinetic temperature structure of the Orion molecular cloud 1 with para-H2CO(303-202, 322-221, and 321-220) using the APEX 12m telescope. This is compared with the temperatures derived from the ratio of the NH3(2,2)/(1,1)…

Astrophysics of Galaxies · Physics 2017-12-27 X. D. Tang , C. Henkel , K. M. Menten , F. Wyrowski , N. Brinkmann , X. W. Zheng , Y. Gong , Y. X. Lin , J. Esimbek , J. J. Zhou , Y. Yuan , D. L. Li , Y. X. He

We present CO observations of a large sample of ultraluminous IR galaxies out to z = 0.3. Most of the galaxies are interacting, but not completed mergers. All but one have high CO(1-0) luminosities, log(Lco [K-km/s-pc^2]) = 9.92 +/- 0.12.…

Astrophysics · Physics 2008-11-26 P. M. Solomon , D. Downes , S. J. E. Radford , J. W. Barrett

The interaction of CO with the Fe3O4(001)-(rt2xrt2)R45{\deg} surface was studied using temperature programmed desorption (TPD), scanning tunneling microscopy (STM) and x-ray photoelectron spectroscopy (XPS), the latter both under ultrahigh…

Aims. Photodissociation by UV light is an important destruction mechanism for CO in many astrophysical environments, ranging from interstellar clouds to protoplanetary disks. The aim of this work is to gain a better understanding of the…

Astrophysics of Galaxies · Physics 2015-05-13 R. Visser , E. F. van Dishoeck , J. H. Black

CO$_2$ is a major component of the icy mantles surrounding dust grains in planet and star formation regions. Understanding its photodesorption is crucial for explaining gas phase abundances in the coldest environments of the interstellar…

We report the detection of H2 in a zabs= 0.0963 Damped Lyman-{\alpha} (DLA) system towards zem = 0.4716 QSO J1619+3342. This DLA has log N(H I) = 20.55 (0.10), 18.13 < log N(H2) < 18.40, [S/H] = -0.62 (0.13), [Fe/S] = -1.00 (0.17) and the…

Astrophysics of Galaxies · Physics 2015-06-22 Raghunathan Srianand , Hadi Rahmani , Sowgat Muzahid , Vijay Mohan