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Related papers: Diffuse Gamma-ray Observations of the Orion Molecu…

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We performed new comprehensive $^{13}$CO($J$=2--1) observations toward NGC 2024, the most active star forming region in Orion B, with an angular resolution of $\sim$100'' obtained with NANTEN2. We found that the associated cloud consists of…

We present a high-resolution $1.5"$ observational study towards two massive dust-and-gas cores, ORI8nw\_2 and ORI2\_6 in Orion Molecular Cloud using the Combined Array for Research in Millimeter-wave Astronomy (CARMA). In both regions the…

Solar and Stellar Astrophysics · Physics 2015-06-16 Zhiyuan Ren , Di Li , Nicholas Chapman

This study presents a catalog of 8107 molecular clouds that covers the entire Galactic plane and includes 98% of the $^{12}$CO emission observed within $b\pm5^\circ$. The catalog was produced using a hierarchical cluster identification…

Astrophysics of Galaxies · Physics 2017-01-11 Marc-Antoine Miville-Deschênes , Norman Murray , Eve J. Lee

Although the deuterium fraction is known to be a powerful evolutionary tracer, its variation within individual molecular cloud cores is still poorly understood. The northern $\int$-shaped filament and 20 individual starless cores in the…

We study the effects of an asymmetric radiation field on the properties of a molecular cloud envelope. We employ observations of carbon monoxide (12CO and 13CO), atomic carbon, ionized carbon, and atomic hydrogen to analyze the chemical and…

Determining temperatures in molecular clouds from ratios of CO rotational lines or from ratios of continuum emission in different wavelength bands suffers from reduced temperature sensitivity in the high-temperature limit. In theory, the…

Astrophysics · Physics 2008-11-26 W. F. Wall

In this study, we investigate the shapes of starless and protostellar cores using hydrodynamic, self-gravitating adaptive mesh refinement simulations of turbulent molecular clouds. We simulate observations of these cores in dust emission,…

Astrophysics · Physics 2011-02-11 S. S. R. Offner , M. R. Krumholz

We have observed several cloud cores in the Orion B (L1630) molecular cloud in the 2-1 transitions of C18O, C17O and 13C18O. We use these data to show that a model where the cores consist of very optically thick C18O clumps cannot explain…

Astrophysics · Physics 2009-11-07 D. Savva , L. T. Little , R. R. Phillips , A. G. Gibb

We present the results of a wide-area mapping of the far-infrared continuum emission toward the Orion complex by using a Japanese balloon-borne telescope. The 155-um continuum emission was detected over a region of 1.5 deg^2 around the KL…

We present results from a 2300 arcmin^2 survey of the Orion A molecular cloud at 450 and 850 micron using the Submillimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope. The region mapped lies directly south of…

Astrophysics · Physics 2008-11-26 Doug Johnstone , John Bally

In this paper, we analyzed 12 years of Fermi LAT gamma-ray data towards three nearby giant molecular clouds (GMCs), i.e., R~CrA, Chamaeleon, and Lupus. We calibrated the gas column density of these regions by using the Planck dust opacity…

High Energy Astrophysical Phenomena · Physics 2023-04-28 Jiahao Liu , Bing Liu , Ruizhi Yang

Strong winds and ultraviolet (UV) radiation from O-type stars disrupt and ionize their molecular core birthplaces, sweeping up material into parsec-size shells. Owing to dissociation by starlight, the thinnest shells are expected to host…

Up to now, mostly relatively simple molecules have been detected in interstellar diffuse molecular clouds in our galaxy, but more complex species have been reported in the diffuse/translucent medium of a z = 0.89 spiral galaxy. We aim at…

Astrophysics of Galaxies · Physics 2017-09-20 V. Thiel , A. Belloche , K. M. Menten , R. T. Garrod , H. S. P. Müller

We present the first results from a new, high resolution, $^{12}$CO(1-0), $^{13}$CO(1-0), and C$^{18}$O(1-0) molecular line survey of the Orion A cloud, hereafter referred to as the CARMA-NRO Orion Survey. CARMA observations have been…

We have investigated the formation and kinematics of sub-mm continuum cores in the Orion A molecular cloud. A comparison between sub-mm continuum and near infrared extinction shows a continuum core detection threshold of $A_V\sim$ 5-10 mag.…

We present a study of the three-dimensional structure of the molecular clouds in the Galactic Centre (GC) using CO emission and OH absorption lines. Two CO isotopologue lines, $^{12}$CO ($J$=1$\rightarrow$0) and $^{13}$CO…

We report a CO(3-2) detection of 23 molecular clouds in the extended ultraviolet (XUV) disk of the spiral galaxy M83 with ALMA. The observed 1kpc^2 region is at about 1.24 times the optical radius (R25) of the disk, where CO(2-1) was…

To investigate the interstellar medium (ISM) and Galactic cosmic rays (CRs) in the solar neighborhood, we analyzed ${\gamma}$-ray data by Fermi Large Area Telescope (LAT) for five nearby molecular cloud regions. Our data includes the…

High Energy Astrophysical Phenomena · Physics 2025-06-23 Tsunefumi Mizuno , Katsuhiro Hayashi , Hinako Ochi , Igor V. Moskalenko , Elena Orlando , Andrew W. Strong

This paper deals with the cosmic-ray penetration into molecular clouds and with the related gamma--ray emission. High energy cosmic rays interact with the dense gas and produce neutral pions which in turn decay into two gamma rays. This…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Stefano Gabici

During the transition phase from a prestellar to a protostellar cloud core, one or several protostars can form within a single gas core. The detailed physical processes of this transition, however, still remain unclear. We present 1.3 mm…