English
Related papers

Related papers: Imaging diffuse clouds: Bright and dark gas mapped…

200 papers

There is a robust polyatomic chemistry in diffuse, partially-molecular interstellar gas that is readily accessible in absorption at radio/mm/sub-mm wavelengths. Accurate column densities are derived owing to the weak internal excitation, so…

Astrophysics of Galaxies · Physics 2023-02-15 Harvey Liszt , Maryvonne Gerin

The factor relating CO emission to molecular hydrogen column density, XCO, is still subject to uncertainty, in particular at low metallicity. Here, to quantify XCO at two different spatial resolutions, we exploit a dust-based method…

We present moderate (1'') and high resolution (0.2'') observations of the CO(2-1) emission at 43 GHz, and radio continuum emission at 1.47 GHz, from the z=4.7 QSO BRI 1202-0725 and the z=4.4 QSO BRI 1335--0417 using the Very Large Array.…

Astrophysics · Physics 2009-11-07 C. L. Carilli , K. Kohno , R. Kawabe , K. Ohta , C. Henkel , K. Menten , M. Yun , A. Petric , Y. Tutui

Using archival, high-resolution far-ultraviolet HST/STIS spectra of 34 Galactic O and B stars, we measure CI column densities and compare them with measurements from the literature of CO and H_2 with regard to understanding the presence of…

Astrophysics of Galaxies · Physics 2014-11-20 Eric B. Burgh , Kevin France , Edward B. Jenkins

Planck cold clumps are among the most promising objects to investigate the initial conditions of the evolution of molecular clouds. In this work, by combing the dust emission data from the survey of Planck satellite with the molecular data…

Solar and Stellar Astrophysics · Physics 2013-10-11 Tie Liu , Yuefang Wu , Huawei Zhang

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. However, until recently, we have not had spectrally resolved C+ surveys to…

Astrophysics of Galaxies · Physics 2015-06-18 W. D. Langer , T. Velusamy , J. L. Pineda , K. Willacy , P. F. Goldsmith

We analyse the CO-dark molecular gas content of simulated molecular clouds from the SILCC-Zoom project. The simulations reach a resolution of 0.1 pc and include H$_2$ and CO formation, radiative stellar feedback and magnetic fields. CO-dark…

Astrophysics of Galaxies · Physics 2020-01-08 D. Seifried , S. Haid , S. Walch , E. M. A. Borchert , T. G. Bisbas

We report observations of the dust cloud L1204 with the Onsala 25-m telescope in the 6 cm (1$_{11}-1_{10}$) transition of \htco. The observed region includes the S140 H${\alpha}$ arc. This spectral line is seen here in absorption against…

We used the ARO 12m antenna to observe emission from the J=1-0 lines of carbon monoxide, \hcop\ and HNC and the J=2-1 line of CS toward and around the continuum peak used for absorption studies and we compare them with CH, HNC, C\p\ and…

Astrophysics of Galaxies · Physics 2016-01-13 Harvey Liszt , Maryvonne Gerin

The 12CO J=4-3 to J=13-12 lines of the interstellar medium from nearby galaxies, newly observable with the Herschel SPIRE Fourier Transform Spectrometer (FTS), offer an opportunity to study warmer, more luminous molecular gas than that…

Astrophysics of Galaxies · Physics 2015-06-23 J. Kamenetzky , N. Rangwala , J. Glenn , P. R. Maloney , A. Conley

We use the moving mesh code AREPO coupled to a time-dependent chemical network to investigate the formation and destruction of molecular gas in simulated spiral galaxies. This allows us to determine the characteristics of the gas that is…

Astrophysics of Galaxies · Physics 2015-06-19 Rowan J. Smith , Simon C. O. Glover , Paul C. Clark , Ralf S. Klessen , Volker Springel

Far-infrared molecular emission is an important tool used to understand the excitation mechanisms of the gas in the inter-stellar medium of star-forming galaxies. In the present work, we model the emission from rotational transitions with…

Astrophysics of Galaxies · Physics 2016-11-23 M. V. Kazandjian , I. Pelupessy , R. Meijerink , F. P. Israel , C. M. Coppola , M. J. F. Rosenberg , M. Spaans

Using the Australia Telescope Compact Array (ATCA), we conducted a survey of CO J=1-0 and J=2-1 line emission towards strongly lensed high-redshift dusty star forming galaxies (DSFGs) previously discovered with the South Pole Telescope…

[Abridged] Do some environments favor efficient conversion of molecular gas into stars? To answer this, we need to be able to estimate the H2 mass. Traditionally, this is done using CO and a few assumptions but the Herschel observations in…

We present the first results on the diffuse transition clouds observed in [CII] line emission at 158 microns (1.9 THz) towards Galactic longitudes near 340deg (5 LOSs) and 20deg (11 LOSs) as part of the GOT C+ survey. Out of the total 146…

Astrophysics of Galaxies · Physics 2015-05-19 T. Velusamy , W. D. Langer , J. L. Pineda , P. F. Goldsmith , D. Li. , H. W. Yorke

We present the results of a survey of CO(1-0) emission in 14 infrared luminous dusty star forming galaxies (DSFGs) at 2 < z < 4 with the NSF's Karl G. Jansky Very Large Array. All sources are detected in CO(1-0), with an ~1arcsec angular…

We acquired ALMA ground state absorption profiles of HCO+ and other molecules toward 33 extragalactic continuum sources seen toward the Galactic anticenter, deriving N(H2) = N(HCO+)/3x10^{-9}. We observed J=1-0 CO emission with the IRAM 30m…

Astrophysics of Galaxies · Physics 2023-07-19 Harvey Liszt , Maryvonne Gerin

A reliable estimate of the molecular gas content in galaxies plays a crucial role in determining their dynamical and star-forming properties. However, H2, the dominant molecular species, is difficult to observe directly, particularly in the…

Astrophysics · Physics 2008-11-26 T. A. Bell , E. Roueff , S. Viti , D. A. Williams

Infrared-dark high-mass clumps are among the most promising objects to study the initial conditions of the formation process of high-mass stars and rich stellar clusters. In this work, we have observed the (3-2) rotational transition of…

Astrophysics of Galaxies · Physics 2015-06-04 F. Fontani , A. Giannetti , M. T. Beltran , R. Dodson , M. Rioja , J. Brand , P. Caselli , R. Cesaroni

We present spatially-resolved imaging obtained with the Australia Telescope Compact Array (ATCA) of three CO lines in two high-redshift gravitationally lensed dusty star-forming galaxies, discovered by the South Pole Telescope. Strong…