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Related papers: Interstellar OH+, H2O+ and H3O+ along the sight-li…

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Submillimeter rotational lines of H2O are a powerful probe in warm gas regions of the ISM, tracing scales and structures ranging from kpc disks to the most compact and dust-obscured regions of galactic nuclei. The ortho-H2O(423-330) line at…

Astrophysics of Galaxies · Physics 2020-02-05 C. Yang , E. González-Alfonso , A. Omont , M. Pereira-Santaella , J. Fischer , A. Beelen , R. Gavazzi

We have made HI 21cm-line absorption measurements using the GMRT towards 15 directions in the Galaxy which are known to have high random velocity clouds as seen in the optical absorption lines of CaII and NaI. For the first time, in 6 out…

Astrophysics · Physics 2007-05-23 Rekhesh Mohan , K. S. Dwarakanath , G. Srinivasan , Jayaram N. Chengalur

Near ultraviolet observations of OH+ and OH in diffuse molecular clouds reveal a preference for different environments. The dominant absorption feature in OH+ arises from a main component seen in CH+ (that with the highest CH+/CH column…

Astrophysics of Galaxies · Physics 2015-06-18 A. J. Porras , S. R. Federman , D. E. Welty , A. M. Ritchey

A high latitude HI 21 cm-line absorption survey toward extragalactic sources was recently completed using the Giant Meterwave Radio Telescope (GMRT). A total of 104 sources with mod(b) > 15 deg. and with a 21 cm flux density greater than 1…

Astrophysics · Physics 2007-05-23 K. S. Dwarakanath

Circumstellar envelopes (CSEs) of a variety of evolved stars have been found to contain ammonia (NH3) in amounts that exceed predictions from conventional chemical models by many orders of magnitude. The observations reported here were…

Results: We report the detection of broad HCO+(1-0) lines (10 mK < T < 0.5 K). The interpretation of 10 of the HCO+ velocity components is conducted in conjunction with that of the associated optically thin 13CO emission. The derived HCO+…

Astrophysics · Physics 2016-08-15 E. Falgarone , G. Pineau Des Forêts , P. Hily-Blant , P. Schilke

We have serendipitously detected a strong O VI-bearing Lyman limit system at z_abs = 0.3558 toward the QSO J1009+0713 (z_em = 0.456) in our survey of low-redshift galaxy halos with the Hubble Space Telescope's Cosmic Origins Spectrograph.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 J. Tumlinson , J. K. Werk , C. Thom , J. D. Meiring , J. X. Prochaska , T. M. Tripp , J. M. O'Meara , M. Okrochkov , K. R. Sembach

As part of the search for the "dark molecular gas (DMG)," we report on the results of HCO$^+$ J = 1-0 absorption observations toward nine bright extragalactic millimeter wave continuum sources. The extragalactic sources are at high Galactic…

Astrophysics of Galaxies · Physics 2018-07-04 Geumsook Park , Bon-Chul Koo , Kee-Tae Kim , Do-Young Byun , Carl E. Heiles

Interstellar ices are largely composed of frozen water. It is important to derive fundamental parameters for H$_2$O ice such as absorption and scattering opacities for which accurate complex refractive indexes are needed. The primary goal…

Instrumentation and Methods for Astrophysics · Physics 2023-12-20 W. R. M. Rocha , M. G. Rachid , M. K. McClure , J. He , H. Linnartz

New HI images from the VLA Galactic Plane Survey (VGPS) show clear absorption features associated with the supernova remnant (SNR) G18.8+0.3. High-resolution $^{13}$CO images reveal that molecular clouds overlap the radio filaments of…

Astrophysics · Physics 2009-11-13 W. W. Tian , D. A. Leahy , Q. D. Wang

We report the detection of \HI 21-cm absorption in the $z=0.96$ early-type lensing galaxy towards MG J0414+0534 with the Green Bank Telescope. The absorption, with total $N_{\rm HI}=1.6 \times 10^{18} (T_{\rm s}/f) {\rm cm}^{-2}$, is…

Astrophysics · Physics 2009-11-13 S. J. Curran , J. Darling , A. D. Bolatto , M. T. Whiting , C. Bignell , J. K. Webb

We report the detection of 23 OH+(1-0) absorption, emission, or P-Cygni-shaped lines and CO(9-8) emission lines in 18 Herschel-selected z=2-6 starburst galaxies with ALMA and NOEMA, taken as part of the Gas And Dust Over cosmic Time (GADOT)…

Astrophysics of Galaxies · Physics 2021-06-23 Dominik A. Riechers , Asantha Cooray , Ismael Perez-Fournon , Roberto Neri

We present new measurements of the interstellar gas-phase oxygen abundance along the sight lines towards 19 early-type galactic stars at an average distance of 2.6 kpc. We derive O {\small I} column densities from {\it HST}/STIS…

We are currently undertaking a large survey for redshifted atomic and molecular absorption ... only one clear and one tentative detection were obtained: HI absorption at z = 0.097 in PKS 1555-140 and OH absorption at z =0.126 in PKS…

Context. The high intensities and narrow bandwidths exhibited by some astronomical masers make them ideal tools for studying star-forming giant molecular clouds. The water maser transition $J_{K_{-1}K_{1}}=5_{32}-4_{41}$ at 620.701 GHz can…

Astrophysics of Galaxies · Physics 2014-09-05 S. C. Jones , M. Houde , M. Harwit , M. Kidger , A. Kraus , C. McCoey , A. Marston , G. Melnick , K. M. Menten , P. Morris , D. Teyssier , V. Tolls

We present MERLIN observations of OH, water and methanol masers towards the young high mass stellar object IRAS 20126+4104. Emission from the 1665-MHz OH, 22-GHz H_2O and 6.7-GHz CH_3OH masers is detected and all originates very close to…

Astrophysics of Galaxies · Physics 2011-07-05 K. A. Edris , G. A. Fuller , R. J. Cohen , S. Etoka

We have used the Submillimeter Wave Astronomy Satellite to map the ground-state 1_{10}-1_{01} transition of ortho-water at 557 GHz in the Orion molecular cloud. Water emission was detected in Orion over an angular extent of about 20 arcmin,…

Using the Very Long Baseline Array and the European VLBI Network, we have observed 22.2 GHz H_2O and 1612 MHz OH masers in the "water fountain" source IRAS 18460-0151. The H_2O maser spectrum has a very wide line-of-sight velocity range…

Solar and Stellar Astrophysics · Physics 2015-06-16 Hiroshi Imai , Shuji Deguchi , Jun-ichi Nakashima , Sun Kwok , Philip J. Diamond

We present a new Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) absorption-line survey to study halo gas around 16 luminous red galaxies (LRGs) at z=0.21-0.55. The LRGs are selected uniformly with stellar mass Mstar>1e11…

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