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Related papers: Strong CH+ J=1-0 emission and absorption in DR21

200 papers

We present a 4.5-4.85 micron R=5000 spectrum of the low mass class I young stellar object GSS 30 IRS1 (L=25L_sun) in the rho Ophiuchus core, observed with the infrared spectrometer (ISAAC) on the Very Large Telescope (VLT-UT1). Strong line…

Astrophysics · Physics 2009-11-07 K. M. Pontoppidan , F. L. Schoeier , E. F. van Dishoeck , E. Dartois

We present Giant Metrewave Radio Telescope (GMRT) observations of redshifted 21-cm absorption from the $z=0.437$ metal line absorption system towards PKS 1243-072. HI absorption is clearly detected; the absorption profile has a velocity…

Astrophysics · Physics 2009-11-07 Nissim Kanekar , Ramana M. Athreya , Jayaram N. Chengalur

We have observed the rotational ground-state (J = 1-0) transitions of DCO+, HN13C and DNC with the IRAM 30m telescope toward the dark cloud LDN 1512 which has exceptionally narrow lines permitting hyperfine splitting to be resolved in part.…

Astrophysics of Galaxies · Physics 2015-05-14 Floris van der Tak , Holger Müller , Michael Harding , Jürgen Gauss

Neutral hydrogen traces gravitational potentials. In the nearby universe, 21cm emission-line surveys show that the bulk of the HI resides in well-formed, optically-luminous galaxies. At high redshift, 21cm line absorption against background…

Astrophysics · Physics 2007-05-23 F. H. Briggs

We report the detection of HCO+(1-0) emission towards the Cloverleaf quasar (z=2.56) through observations with the Very Large Array. This is the first detection of ionized molecular gas emission at high redshift (z>2). HCO+ emission is a…

We present the results of three separate searches for HI 21-cm absorption in a total of twelve damped Lyman-alpha absorption systems (DLAs) and sub-DLAs over the redshift range z = 0.86-3.37. We find no absorption in the five systems for…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. J. Curran , P. Tzanavaris , J. K. Darling , M. T. Whiting , J. K. Webb C. Bignell , R. Athreya , M. T. Murphy

The [CII] fine--structure line at 158um is an excellent tracer of the warm diffuse gas in the ISM and the interfaces between molecular clouds and their surrounding atomic and ionized envelopes. Here we present the initial results from…

We present follow-up observations to those of Geballe & Oka (2010), who found high column densities of H3+ ~100 pc off of the Galactic center (GC) on the lines of sight to 2MASS J17432173-2951430 (J1743) and 2MASS J17470898-2829561 (J1747).…

Astrophysics of Galaxies · Physics 2015-05-27 M. Goto , T. Usuda , T. R. Geballe , N. Indriolo , B. J. McCall , Th. Henning , T. Oka

We report additional detections of the chloronium molecular ion, H$_2$Cl$^+$, toward four bright submillimeter continuum sources: G29.96, W49N, W51, and W3(OH). With the use of the HIFI instrument on the Herschel Space Observatory, we…

Context: Existing SWAS observations and future HIFI/Herschel data require a clear sense of the information content of water emission and absorption lines. Aims: Investigate wether the ground-state transition of ortho-H2O, 1_(10)-1_(01), at…

Astrophysics · Physics 2009-11-11 D. R. Poelman , M. Spaans , A. G. G. M. Tielens

We derive the dense core structure and the water abundance in four massive star-forming regions which may help understand the earliest stages of massive star formation. We present Herschel-HIFI observations of the para-H2O 1_11-0_00 and…

Astrophysics of Galaxies · Physics 2015-05-19 M. Marseille , F. F. S. van der Tak , F. Herpin , F. Wyrowski , L. Chavarria , B. Pietropaoli , WISH consortium

We present detailed evidence for a warm absorber in the Seyfert 1 galaxy MCG--6-30-15 and dispute earlier claims for relativistic O line emission. The HETG spectra show numerous narrow, unresolved (FWHM < 200 km/s) absorption lines from a…

Seven rotational and fine-structure transitions of the deuterated molecular ion SD+ in the X 3S- ground electronic state have been measured in the 271-863 GHz region in the laboratory. This ion has been produced by DC-glow discharge using a…

Astrophysics of Galaxies · Physics 2024-03-25 Mitsunori Araki , Valerio Lattanzi , Christian P. Endres , Paula Caselli

Using the 100-m Green Bank Telescope, we have conducted a cm-wavelength search for CO J=1-0 line emission towards the high-redshift, far-infrared luminous object, HDF850.1 over the redshift interval 3.3<z<5.4. Despite the wealth of existing…

Astrophysics · Physics 2008-11-26 J. Wagg , D. H. Hughes , I. Aretxaga , E. L. Chapin , J. S. Dunlop , E. Gaztanaga , M. Devlin

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

The very massive star, Eta Carinae, is enshrouded in an unusual complex of stellar ejecta, which is highly depleted in C and O, and enriched in He and N. This circumstellar gas gives rise to distinct absorption components corresponding to…

Astrophysics · Physics 2009-11-11 E. Verner , F. Bruhweiler , K. E. Nielsen , T. R. Gull , G. Vieira Kober , M. Corcoran

HE0141-3932 (zem=1.80) is a bright blue radio-quite quasar which reveals an emission line spectrum with an unusually weak Ly-alpha line. In addition, large redshift differences (Delta z=0.05) are observed between high ionization and low…

Astrophysics · Physics 2009-11-11 S. A. Levshakov , I. I. Agafonova , D. Reimers , C. Fechner , E. Janknecht , S. Lopez

We present echelle spectrophotometry of the Galactic H II region S 311. The data have been taken with the Very Large Telescope UVES echelle spectrograph in the 3100 to 10400 angstroms range. We have measured the intensities of 263 emission…

Astrophysics · Physics 2009-11-13 J. Garcia-Rojas , C. Esteban , A. Peimbert , M. Peimbert , M. Rodriguez , M. T. Ruiz

We report the detection of HI absorption towards the inner double of the double-double radio galaxy (DDRG) J1247+6723 with the Giant Metrewave Radio Telescope (GMRT). The inner double is a Giga-hertz peaked spectrum (GPS) source with a…

Astrophysics · Physics 2008-11-26 D. J. Saikia , Neeraj Gupta , C. Konar

DR21(OH) is a pc-scale massive, 7000 Msun clump hosting three massive dense cores (MDCs) at an early stage of their evolution. We present a high angular-resolution mosaic, covering 70" by 100", with the IRAM PdBI at 3 mm to trace the dust…

Astrophysics of Galaxies · Physics 2015-05-30 T. Csengeri , S. Bontemps , N. Schneider , F. Motte , F. Gueth , J. L. Hora