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Related papers: Mid- and high-J CO observations towards UCHIIs

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We present Very Large Array 7 mm continuum observations of four Ultra-Compact (UC)HII regions, observed previously at 1.3 cm, in order to investigate the nature of the compact radio sources associated with these regions. We detected a total…

Interferometer observations of millimeter-continuum (OVRO) and single-dish observations of HCO+ and H13CO+ J=1-0, 3-2, and 4-3 (JCMT, IRAM 30m) are presented of nine embedded low-mass young stellar objects (YSOs) in Taurus. All nine objects…

We present CO observations of 9 ULIRGs at z~2 with S(24\mu m)>1mJy, previously confirmed with the mid-IR spectra in the Spitzer First Look Survey. All targets are required to have accurate redshifts from Keck/GEMINI near-IR spectra. Using…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Lin Yan , L. ~J. Tacconi , N. Fiolet , A. Sajina , A. Omont , D. Lutz , M. Zamojski , R. Neri , P. Cox , K. ~M. Dasyra

We present the results of our ALMA observations of eleven (ultra)luminous infrared galaxies ((U)LIRGs) at J=4-3 of HCN, HCO+, HNC and J=3-2 of HNC. This is an extension of our previously published HCN and HCO+ J=3-2 observations to multiple…

Astrophysics of Galaxies · Physics 2018-04-18 Masatoshi Imanishi , Kouichiro Nakanishi , Takuma Izumi

Expansion of wind-blown bubbles or HII regions lead to formation of shocks in the interstellar medium, which compress surrounding gas into dense layers. We made spatially and velocity-resolved observations of the RCW~120 PDR and nearby…

Astrophysics of Galaxies · Physics 2023-01-18 M. S. Kirsanova , Ya. N. Pavlyuchenkov , A. O. H. Olofsson , D. A. Semenov , A. F. Punanova

We report on one of the highest sensitivity surveys for molecular lines in the frequency range 6.0 to 7.4 GHz conducted to date. The observations were done with the 305m Arecibo Telescope toward a sample of twelve intermediate/high-mass…

Astrophysics of Galaxies · Physics 2020-07-08 W. S. Tan , E. D. Araya , L. E. Lee , P. Hofner , S. Kurtz , H. Linz , L. Olmi

We have detected CO(4-3) in the z=3.8 radio galaxy 4C 41.17 with the IRAM Interferometer. The CO is in two massive (M_dyn ~ 6 x 10^10 M_Sun) systems separated by 1.8" (13 kpc), and by 400 km/s in velocity, which coincide with two different…

We present in this paper the results of high spectral resolution ($R$=88,100) spectroscopy at 4.7 $\mu$m with iSHELL/IRTF of hot molecular gas close to the massive binary protostar W3 IRS5. The binary was spatially resolved and the spectra…

Astrophysics of Galaxies · Physics 2022-08-31 Jialu Li , Adwin Boogert , Andrew G. Barr , Alexander G. G. M. Tielens

The eastern border of the SNR G18.8+0.3, close to an HII regions complex, is a very interesting region to study the molecular gas that it is probably in contact with the SNR shock front. We observed the aforementioned region using the…

Astrophysics of Galaxies · Physics 2015-06-11 S. Paron , M. E. Ortega , A. Petriella , M. Rubio , G. Dubner , E. Giacani

Context: We analyze the NGC 2024 HII region and molecular cloud interface using [12CII] and [13CII] observations. Aims: We attempt to gain insight into the physical structure of the interface layer between the molecular cloud and the HII…

Astrophysics of Galaxies · Physics 2015-06-04 U. U. Graf , R. Simon , J. Stutzki , S. W. J. Colgan , X. Guan , R. Güsten , R. Hartogh , C. E. Honingh , H. -W. Hübers

Context. The derived physical parameters for young HII regions are normally determined assuming the emission region to be optically thin. However, this assumption is unlikely to hold for young HII regions such as hyper-compact HII(HCHII)…

The offsets between the radial velocities of the rotational transitions of carbon monoxide and the fine structure transitions of neutral and singly ionized carbon are used to test the hypothetical variation of the fine structure constant,…

Astrophysics of Galaxies · Physics 2017-08-23 S. A. Levshakov , K. -W. Ng , C. Henkel , B. Mookerjea

Photon Dominated Regions (PDRs) are interfaces between the mainly ionized and mainly molecular material around young massive stars. Analysis of the physical and chemical structure of such regions traces the impact of far-ultraviolet…

Astrophysics of Galaxies · Physics 2017-02-22 Z. Nagy , Y. Choi , V. Ossenkopf-Okada , F. F. S. van der Tak , E. A. Bergin , M. Gerin , C. Joblin , M. Roellig , R. Simon , J. Stutzki

(Abridged) Context. Massive star formation is associated with energetic processes, which result in significant gas cooling via far-infrared (IR) lines. Velocity-resolved observations can constrain the kinematics of the gas, allowing the…

Astrophysics of Galaxies · Physics 2023-11-29 Hoang Thanh Dat , Agata Karska , Min Young Lee , Friedrich Wyrowski , Le Ngoc Tram , Aiyuan Y. Yang , Karl M. Menten

We present an analysis of the HI and CO gas in conjunction with the Planck/IRAS submillimeter/far-infrared dust properties toward the most outstanding high latitude clouds MBM 53, 54, 55 and HLCG 92-35 at b = -30 deg to -45 deg. The CO…

This is the second paper of a series making use of Herschel/PACS spectroscopy of evolved stars in the THROES catalogue to study the inner regions of their circumstellar envelopes (CSEs). We analyze the CO emission spectra, including a large…

Solar and Stellar Astrophysics · Physics 2019-02-13 J. M. da Silva Santos , J. Ramos-Medina , C. Sánchez Contreras , P. García-Lario

Motivated by recent observations with Herschel/PACS, and the availability of new rate coefficients for the collisional excitation of CO (Yang et al. 2010), the excitation of warm astrophysical CO is revisited with the use of numerical and…

Astrophysics of Galaxies · Physics 2015-06-04 David A. Neufeld

Absorption lines at high redshift in front of quasars are rare in the mm domain. Only five associated and five intervening systems have been reported in the literature. These bring very useful information complementary to emission lines,…

Astrophysics of Galaxies · Physics 2023-12-19 Francoise Combes , Neeraj Gupta

Atomic carbon ([CI]) is a key species in the carbon chemistry of the interstellar medium (ISM). Using the Submillimeter Wave Astronomy Satellite (SWAS), we conducted a [CI]($^3$P$_1$--$^3$P$_0$) 492 GHz survey covering approximately 4…

Context: We investigated the molecular gas associated with 6.7 GHz methanol masers throughout the Galaxy using a J=1-0 transition of the CO isotopologues. Methods:Using the 13.7-meter telescope at the Purple Mountain Observatory (PMO), we…

Solar and Stellar Astrophysics · Physics 2014-09-05 Zhiyuan Ren , Yuefang Wu , Tie Liu , Lixin Li , Di Li , Binggang Ju