Results 1 to 10 of about 42,847 (320)
The Astrophysical Journal, 2023 We present the results of ALMA-ACA 7 m array observations in ^12 CO( J = 2–1), ^13 CO( J = 2–1), and C ^18 O( J = 2–1) line emission toward the molecular-gas disk in the Local Group spiral galaxy M33 at an angular resolution of 7.″31 × 6.″50 (30 × 26 pc).
Kazuyuki Muraoka +21 more
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Absorption-line Observations of and CO in Sight Lines Toward the Vela and W28 Supernova Remnants
The Astrophysical Journal, 2023 Supernova remnants act as particle accelerators, providing the cosmic-ray protons that permeate the interstellar medium and initiate the ion–molecule reactions that drive interstellar chemistry. Enhanced fluxes of cosmic-ray protons in close proximity to
Nick Indriolo
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A Search for OH 18 cm Emission from Intermediate-velocity Gas at High Galactic Latitudes
The Astrophysical Journal, 2023 We present search results of 22 high-latitude (∣ b ∣ > 25°) 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 −90 ≤ V _LSR ≤ −20 km
Allison J. Smith, D. Anish Roshi
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A Herschel [C II] Galactic plane survey II: CO-dark H2 in clouds [PDF]
, 2014 ABRIDGED: Context: HI and CO large scale surveys of the Milky Way trace the diffuse atomic clouds and the dense shielded regions of molecular hydrogen clouds.
Goldsmith, P. F. +4 more
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Abundance Ratios of OH/CO and HCO+/CO as Probes of the Cosmic-Ray Ionization Rate in Diffuse Clouds
The Astrophysical Journal, 2023 The cosmic-ray ionization rate (CRIR, ζ _2 ) is one of the key parameters controlling the formation and destruction of various molecules in molecular clouds. However, the current most commonly used CRIR tracers, such as ${{\rm{H}}}_{3}^{+}$ , OH ^+ , and
Gan Luo +8 more
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Galaxy chemical evolution models: The role of molecular gas formation [PDF]
, 2017 In our classical grid of multiphase chemical evolution models, star formation in the disc occurs in two steps: first, molecular gas forms, and then stars are created by cloud-cloud collisions or interactions of massive stars with the surrounding ...
Ascasibar, Yago +4 more
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Evidence for a Molecular Cloud Origin for Gamma-Ray Bursts: Implications for the Nature of Star Formation in the Universe [PDF]
, 2001 It appears that the majority of rapidly-, well-localized gamma-ray bursts with undetected, or dark, optical afterglows, or `dark bursts' for short, occur in clouds of size R > 10L_{49}^{1/2} pc and mass M > 3x10^5L_{49} M_{sun}, where L is the isotropic ...
Dal Fiume D. +7 more
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Two populations of diffuse molecular clouds
The Astrophysical Journal, 1988 Sensitive CO and (C-13)O measurements have been made toward a number of diffuse clouds and high-latitude molecular clouds (HLCs). The results suggest that the diffuse clouds are an inhomogeneous class of objects which can be separated according to their CO column density.
Elizabeth A. Lada, Leo Blitz
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Far-ultraviolet Dust Extinction and Molecular Hydrogen in the Diffuse Milky Way Interstellar Medium
The Astrophysical Journal, 2023 We aim to compare variations in the full-UV dust extinction curve (912–3000 Å), with the H i /H _2 /total H content along diffuse Milky Way sightlines, to investigate possible connections between ISM conditions and dust properties. We combine an existing
Dries Van De Putte +4 more
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Frontiers in Astronomy and Space Sciences, 2021 Stellar systems are often formed through the collapse of dense molecular clouds which, in turn, return copious amounts of atomic and molecular material to the interstellar medium.
Duncan V. Mifsud +6 more
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