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Related papers: Modeling of diffuse molecular gas applied to HD 10…

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We present a comprehensive survey of boron abundances in diffuse interstellar clouds from observations made with the Space Telescope Imaging Spectrograph (STIS) of the Hubble Space Telescope. Our sample of 56 Galactic sight lines is the…

Astrophysics of Galaxies · Physics 2011-02-02 A. M. Ritchey , S. R. Federman , Y. Sheffer , D. L. Lambert

We present a detailed analysis of the H_2 and HD absorption lines detected in the Damped Lyman-alpha (DLA) system at z_abs=2.3377 towards the quasar Q1232+082. We show that this intervening cloud has a covering factor smaller than unity and…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-10 A. V. Ivanchik , P. Petitjean , S. A. Balashev , R. Srianand , D. A. Varshalovich , C. Ledoux , P. Noterdaeme

We present fully sampled ^{12}$CO, ^{13}CO J=2-1, 3-2 maps of the inner $\sim 1'\times 1'$ region of NGC 1068. We combine these measurements with an existing interferometric map of ^{12}CO J=1-0 that includes single dish data and thus…

Astrophysics · Physics 2009-10-31 Padeli. P. Papadopoulos , E. R. Seaquist

We devise a physical model of formation and distribution of molecular gas clouds in galaxies. We use the model to predict the intensities of rotational transition lines of carbon monoxide (CO) and the molecular hydrogen (H$_{\rm 2}$)…

Astrophysics of Galaxies · Physics 2020-10-14 Shigeki Inoue , Naoki Yoshida , Hidenobu Yajima

We aim to better understand the emission of molecular tracers of the diffuse and dense gas in giant molecular clouds and the influence that metallicity, optical extinction, density, far-UV field, and star formation rate have on these…

We report a detection in the interstellar medium of an infrared transition within the electronic ground state of the deuterated hydrogen molecule, HD. Through a deep integration with the Short-Wavelength-Spectrometer on ISO, the pure…

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

HCN is considered a good tracer of the dense molecular gas that serves as fuel for star formation. However, recent large-scale surveys of giant molecular clouds (GMCs) have detected extended HCN line emission. Such observations often…

Astrophysics of Galaxies · Physics 2022-02-02 J. R. Goicoechea , F. Lique , M. G. Santa-Maria

Chemical reactions in starless molecular clouds are heavily dependent on interactions between gas phase material and solid phase dust and ices. We have observed the abundance and distribution of molecular gases in the cold, starless core DC…

Astrophysics of Galaxies · Physics 2013-01-15 E. E. Hardegree-Ullman , J. Harju , M. Juvela , O. Sipila , D. C. B. Whittet , S. Hotzel

We present a spectral line analysis of the hot molecular core G10.47+0.03 (hereafter, G10). Our aim is to determine molecular abundances and excitation conditions across a wide spectral range inaccessible to ground-based observatories. We…

A new molecular hydrogen cloud is found in the sub-damped Ly-alpha absorber [log N(HI)=19.88+/-0.05] at the redshift z=1.15 toward the bright quasar HE0515-4414 (zem = 1.71). More than 30 absorption features in the Lyman band system of H2…

Astrophysics · Physics 2009-11-10 D. Reimers , R. Baade , R. Quast , S. A. Levshakov

We use high signal-to-noise ratio, high-resolution VLT-UVES data of Q J0643-5041 amounting to a total of more than 23 hours exposure time and fit the neutral hydrogen, metals and H2 absorption features with multiple-component Voigt…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-09 D. Albornoz Vásquez , H. Rahmani , P. Noterdaeme , P. Petitjean , R. Srianand , C. Ledoux

Physical conditions within DLAs can reveal the star formation history, determine the chemical composition of the associated ISM, and hence document the first steps in the formation of present day galaxies. Here we present calculations that…

Astrophysics · Physics 2009-09-29 Raghunathan Srianand , Gargi Shaw , Gary Ferland , Patrick Petitjean , Cedric Ledoux

We present the Spitzer spectroscopic mapping observations toward the central kpc region of the nearby elliptical LINER galaxy, NGC 4278, by using the Infrared Spectrograph (IRS). These observations reveal rich mid-IR emission features of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Yuping Tang , Qiusheng Gu , Shuinai Zhang , Baitian Tang

We report on the detection of deuterated molecular hydrogen, HD, at $z = 0.18$. HD and H$_{\rm 2}$ are detected in HST/COS data of a low metallicity ($Z \sim 0.07Z_\odot$) damped Ly$\alpha$ system at $z = 0.18562$ toward QSO B0120$-$28,…

Astrophysics of Galaxies · Physics 2015-06-18 Cristina M. Oliveira , Kenneth R. Sembach , Jason Tumlinson , John O'Meara , Christopher Thom

We derive total (atomic + molecular) hydrogen densities in giant molecular clouds (GMCs) in the nearby spiral galaxy M33 using a method that views the atomic hydrogen near regions of recent star formation as the product of…

Astrophysics of Galaxies · Physics 2015-05-27 J. S. Heiner , R. J. Allen , P. C. van der Kruit

We aim to compare variations in the full-UV dust extinction curve (912-3000 Angstrom), with the HI/H$_2$/total H content along diffuse Milky Way sightlines, to investigate possible connections between ISM conditions and dust properties. We…

Astrophysics of Galaxies · Physics 2023-02-15 Dries Van De Putte , Stefan I. B. Cartledge , Karl D. Gordon , Geoffrey C. Clayton , Julia Roman-Duval

We present Atacama Large Millimeter/submillimeter Array Band 3 observations of N$_2$H$^+$ (1-0) and CH$_3$CN (5-4), as well as Band 7 observations of the H$_2$CO molecular line emissions from the protostellar system GGD 27-MM2(E). Through…

Context. Molecular Clouds (MCs) are the place where stars are formed and their feedback starts to take place, regulating the evolution of galaxies. Therefore, MCs represent the critical scale at which to study how ultra-violet (UV) photons…

Astrophysics of Galaxies · Physics 2025-03-12 Fabio Di Mascia , Andrea Pallottini , Laura Sommovigo , Davide Decataldo

Molecular outflows powered by young protostars strongly affect the kinematics and chemistry of the natal molecular cloud through strong shocks resulting in substantial modifications of the abundance of several species. As part of the…

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