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Related papers: CO and C_2 Absorption Toward W40 IRS 1a

200 papers

The relative abundances of atomic and molecular species in planet-forming disks around young stars provide important constraints on photochemical disk models and provide a baseline for calculating disk masses from measurements of trace…

Solar and Stellar Astrophysics · Physics 2015-06-22 Kevin France , Gregory J. Herczeg , Matthew McJunkin , Steven V. Penton

Diffusion of species in icy dust grain mantles is a fundamental process that shapes the chemistry of interstellar regions; yet measurements of diffusion in interstellar ice analogs are scarce. Here we present measurements of CO diffusion…

Astrophysics of Galaxies · Physics 2018-01-24 Ilsa R. Cooke , Karin I. Öberg , Edith C. Fayolle , Zoe Peeler , Jennifer B. Bergner

Molecular hydrogen (H$_2$) is by far the most abundant molecule in the Universe. However, due to the low emissivity of H$_2$, carbon monoxide (CO) is widely used instead to trace molecular gas in galaxies. The relative abundances of these…

Astrophysics of Galaxies · Physics 2025-04-30 Sergei Balashev , Daria Kosenko , Pasquier Noterdaeme

We examine 20 diffuse and translucent Galactic sight lines and extract the column densities of the ^12CO and ^13CO isotopologues from their ultraviolet A--X absorption bands detected in archival Space Telescope Imaging Spectrograph data…

Astrophysics · Physics 2009-11-13 Y. Sheffer , M. Rogers , S. R. Federman , D. L. Lambert , R. Gredel

Using the IRAM 30m telescope and the Plateau de Bure interferometer we have detected the \ctwo and the CO 3$-$2, 4$-$3, 6$-$5, 7$-$6 transitions as well as the dust continuum at 3 and 1.2 mm towards the distant luminous infrared galaxy IRAS…

Astrophysics · Physics 2009-11-13 Y. Ao , A. Weiss , D. Downes , F. Walter , C. Henkel , K. M. Menten

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

We present new groundbased 3 $\mu$m spectra of 14 young stellar objects with H_2O ice absorption bands. The broad absorption feature at 3.47 $\mu$m was detected toward all objects and its optical depth is correlated with the optical depth…

Astrophysics · Physics 2009-10-31 T. Y. Brooke , K. Sellgren , T. R. Geballe

We present first results of neutral carbon ([CI], 3P1 - 3P0 at 492 GHz) and carbon monoxide (13CO, J = 1 - 0) mapping in the Vela Molecular Ridge cloud C (VMR-C) and G333 giant molecular cloud complexes with the NANTEN2 and Mopra…

Astrophysics of Galaxies · Physics 2015-06-23 N. Lo , M. R. Cunningham , P. A. Jones , L. Bronfman , P. C. Cortes , R. Simon , V. Lowe , L. Fissel , G. Novak

This paper presents Spitzer-IRS spectroscopy of the CO2 15.2 micron bending mode toward a sample of 50 embedded low-mass stars in nearby star-forming clouds, taken mostly from the ``Cores to Disks (c2d)'' Legacy program. The average…

We study four lines of sight that probe the transition from diffuse molecular gas to molecular cloud material in Taurus. Measurements of atomic and molecular absorption are used to infer the distribution of species and the physical…

We present the detection of carbon monoxide molecules (CO) at z=1.6408 towards the quasar SDSSJ160457.50+220300.5 using the VLT Ultraviolet and Visual Echelle Spectrograph. CO absorption is detected in at least two components in the first…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 P. Noterdaeme , C. Ledoux , R. Srianand , P. Petitjean , S. Lopez

We measure the CO-to-H$_2$ conversion factor ($\alpha_\mathrm{CO}$) in 37 galaxies at 2~kpc resolution, using dust surface density inferred from far-infrared emission as a tracer of the gas surface density and assuming a constant…

The dense cloud associated with W40, one of the nearby H II regions, has been studied in millimeter-wave molecular lines and in 1.2 mm continuum. Besides, 1280 MHz and 610 MHz interferometric observations have been done. The cloud has…

Astrophysics of Galaxies · Physics 2015-06-17 L. Pirogov , D. K. Ojha , M. Thomasson , Y. -F. Wu , I. Zinchenko

Carbon monoxide (CO) is the most commonly used tracer of molecular gas in the inner regions of protoplanetary disks. CO can be used to constrain the excitation and structure of the circumstellar environment. Absorption line spectroscopy…

Solar and Stellar Astrophysics · Physics 2021-09-06 Matthew McJunkin , Kevin France , Eric B. Burgh , Gregory J. Herczeg , Rebecca Schindhelm , Joanna Brown , Alexander Brown

Carbon dioxide is abundant in ice mantles of dust grains; some is found in the pure crystalline form as inferred from the double peak splitting of the bending profile at about 650 cm$^{-1}$. To study how CO$_2$ segregates into the pure form…

Instrumentation and Methods for Astrophysics · Physics 2017-11-01 Jiao He , Gianfranco Vidali

Using the Karl G. Jansky Very Large Array (VLA), we have detected absorption lines due to carbon-monoxide, CO(J=0-1), and the cyano radical, CN(N=0-1), associated with radio galaxy B2 0902+34 at redshift z=3.4. The detection of…

H$_{\rm I}$ 21-cm and $^{12}$CO 2.6-mm line emissions respectively trace the atomic and molecular gas phases, but they miss most of the opaque H$_{\rm I}$ and diffuse H$_2$ present in the Dark Neutral Medium (DNM) at the transition between…

High Energy Astrophysical Phenomena · Physics 2018-03-28 Q. Remy , I. A. Grenier , D. J. Marshall , J. M. Casandjian

Using the Atacama Large Millimeter/submillimeter Array, we have made the first high spatial and spectral resolution observations of the molecular gas and dust in the prototypical blue compact dwarf galaxy II Zw 40. The CO(2-1) and CO(3-2)…

Astrophysics of Galaxies · Physics 2016-09-07 Amanda A. Kepley , Adam K. Leroy , Kelsey E. Johnson , Karin Sandstrom , C. -H. Rosie Chen

FUSE and IUE observations of Sk -69 246, a WN 6 star to the north of 30 Dor, reveal the existence of LMC interstellar gas in at least 3 velocity components.In one of these components FUSE spectra show strong absorption by molecular hydrogen…

Astrophysics · Physics 2009-11-07 Hartmut Bluhm , Klaas S. de Boer

We have obtained a moderate resolution spectrum of the quasar PKS 0528-250 with the Red Channel Spectrograph on the Multiple Mirror Telescope (MMT) in order to study a damped Lyman alpha absorption line system at z = 2.8115. We obtain a new…

Astrophysics · Physics 2016-08-30 Jian Ge , Jill Bechtold , Constance Walker , John , H. Black