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Related papers: Small carbon chains in circumstellar envelopes

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Stromgren indices v and b are combined with broad-band index I, and a new index p, the short wavelength half of the v band, to estimate CN 4215A molecular absorption in a sample of stars in M22. The results have been used to estimate carbon…

Astrophysics · Physics 2007-05-23 David Peat , Raymond Butler

We present high angular resolution 1.3 mm continuum, methyl cyanide molecular line, and 7 mm continuum observations made with the Submillimeter Array and the Very Large Array, toward the most highly obscured and southern part of the massive…

Astrophysics · Physics 2009-11-13 Luis A. Zapata , Paul T. P. Ho , Luis F. Rodriguez , Peter Schilke , Stan Kurtz

We observe 84 candidate young high-mass sources in the rare isotopologues C17O and C18O to investigate whether there is evidence for depletion (freeze-out) towards these objects. Observations of the J=2-1 transitions of C18O and C17O are…

Astrophysics · Physics 2009-11-13 H. S. Thomas , G. A. Fuller

Spectra from the Keck HIRES instrument of the Lyman alpha forests in the lines of sight to the A and C components of the gravitationally lensed QSO Q1422+231 were used to investigate the structure of the intergalactic medium at mean…

Astrophysics · Physics 2009-11-06 Michael Rauch , Wallace L. W. Sargent , Thomas A. Barlow , Robert F. Carswell

We have made the first detection of circumstellar absorption lines of the 12C13C (Phillips) system 1-0 band and the 12C16O first-overtone 2-0 band in the spectrum of the post-AGB star HD56126 (IRAS07134+1005). The rotational temperatures…

Astrophysics · Physics 2009-10-30 Eric J. Bakker , David L. Lambert

21cm spectral-line and continuum observations of ten compact planetary nebulae have been made with the Very Large Array. Circumnebular atomic hydrogen is identified in the planetary nebulae SwSt1, M3-35, and possibly in Hu2-1. The…

Astrophysics · Physics 2015-06-24 G. T. Gussie , A. R. Taylor

We analyze circumgalactic medium (CGM) in a suite of high-resolution cosmological re-simulations of a Milky-Way size galaxy and show that CGM properties are quite sensitive to details of star formation--feedback loop modelling. The…

Astrophysics of Galaxies · Physics 2016-03-09 Cameron J. Liang , Andrey V. Kravtsov , Oscar Agertz

We have conducted Q-band (30 GHz $-$ 50 GHz) line survey observations toward a carbon-chain emission peak in the Serpens South cluster-forming region with the extended Q-band (eQ) receiver installed on the Nobeyama 45 m radio telescope.…

The C-rich AGB star IRC+10216 undergoes strong mass loss, and quasi-periodic density enhancements in the circumstellar matter have been reported. CO is ubiquitous in the CSE, while CCH emission comes from a spatially confined shell. With…

Observations of extragalactic objects need to be corrected for Galactic absorption and this is often accomplished by using the measured 21 cm HI column. However, within the beam of the radio telescope there are variations in the HI column…

Astrophysics · Physics 2009-11-10 Joel N. Bregman , Megan C. Novicki , Jessica E. Krick , John S. Arabadjis

We measured the galactic hydrogen column densities to the neutron-star binaries GX 17+2, 4U 1705-44, and 4U 1728-34 by modeling the Mg and Si absorption edges found in high-resolution X-ray spectra obtained by the Chandra X-ray Observatory.…

Astrophysics · Physics 2008-10-02 Patricia Wroblewski , Tolga Guver , Feryal Ozel

Circumstellar discs are expected to be the nursery of planets. Grain growth within such discs is the first step in the planet formation process. The Bok globule CB 26 harbours such a young disc. We present a detailed model of the edge-on…

The 21 cm hyperfine transition of the atomic hydrogen (HI) in ground state is a powerful probe of the neutral gas content of the universe. This radio frequency transition has been used routinely for decades to observe, both in emission and…

Astrophysics of Galaxies · Physics 2019-11-26 Preetha Saha , Nirupam Roy , Mukul Bhattacharya

A non-LTE analysis of C I lines at 1.068-1.069 micron was carried out for selected 46 halo/disk stars covering a wide metallicity range (-3.7 <[Fe/H]< +0.3), based on the spectral data collected with IRCS+AO188 of the Subaru Telescope, in…

Solar and Stellar Astrophysics · Physics 2015-06-15 Yoichi Takeda , Masahide Takada-Hidai

Within a few parsecs around the central Black Hole Sgr A*, chemistry in the dense molecular cloud material of the circumnuclear disk (CND) can be affected by many energetic phenomena such as high UV-flux from the massive central star…

The article "Confirmation of interstellar phosphine towards asymptotic giant branch star IRC+10216" by A. Manna and S. Pal uses ALMA data of the C-star envelope IRC+10216 to claim a confirmation of the detection of PH3 in this source. The…

Astrophysics of Galaxies · Physics 2025-02-05 M. Agundez , L. Velilla-Prieto , J. P. Fonfria , J. Cernicharo

We present the results from an analysis of the 8727ang forbidden [C I] line in high-resolution Gemini-S/bHROS spectra of three CEMP stars. We find the [C/Fe] ratios based on the [C I] abundances of the two most Fe-rich stars in our sample…

Astrophysics · Physics 2009-11-13 S. C. Schuler , S. J. Margheim , T. Sivarani , M. Asplund , V. V. Smith , K. Cunha , T. C. Beers

Observations of various molecular lines toward a disk region of a nearby galaxy are now feasible, and they are being employed as diagnostic tools to study star-formation activities there. However, the spatial resolution attainable for a…

Astrophysics of Galaxies · Physics 2019-07-17 Yuri Nishimura , Yoshimasa Watanabe , Nanase Harada , Kotaro Kohno , Satoshi Yamamoto

We have mapped 11 compact high-velocity clouds (CHVCs) in the 21-cm line emission of neutral, atomic hydrogen, using the Effelsberg 100-m radio telescope. The aim of our observations was to study the overall distribution of the warm neutral…

Astrophysics · Physics 2009-11-10 T. Westmeier , C. Bruens , J. Kerp

Diffuse gamma-ray emission from interstellar clouds results largely from cosmic ray (CR) proton collisions with ambient gas, regardless of the gas state, temperature, or dust properties of the cloud. The interstellar medium is predominantly…

High Energy Astrophysical Phenomena · Physics 2017-01-11 Ryan D. Abrahams , Alex Teachey , Timothy A. D. Paglione
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