First interstellar detection of OH

  title={First interstellar detection of OH},
  author={Friedrich Wyrowski and Karl M. Menten and Rolf Guesten and Arnaud Belloche},
  journal={arXiv: Astrophysics of Galaxies},
The Atacama Pathfinder Experiment (APEX) 12m telescope was used to observe the N=1-0, J=0-1 ground state transitions of OH+ at 909.1588 GHz with the CHAMP+ heterodyne array receiver. Two blended hyperfine structure transitions were detected in absorption against the strong continuum source Sagittarius B2(M) and in several pixels offset by 18". Both, absorption from Galactic center gas as well as absorption from diffuse clouds in intervening spiral arms in a velocity range from -116 to 38.5 km/s… 

Figures and Tables from this paper

Herschel/HIFI Discovery of HCL^+ in the Interstellar Medium

The radical ion HCl+, a key intermediate in the chlorine chemistry of the interstellar gas, has been identified for the first time in the interstellar medium with the Herschel Space Observatory's

Herschel/HIFI observations of interstellar OH+ and H2O+ towards W49N: a probe of diffuse clouds with a small molecular fraction

We report the detection of absorption by interstellar hydroxyl cations and water cations, along the sight-line to the bright continuum source W49N. We have used Herschel's HIFI instrument, in dual

The EDIBLES survey

We report cosmic ray ionization rates toward ten reddened stars studied within the framework of the EDIBLES (ESO Diffuse Interstellar Bands Large Exploration Survey) program, using the VLT-UVES. For

Ubiquitous Argonium, ArH⁺, in the Diffuse Interstellar Medium

ArH+ is isoelectronic with HCl. The J = 1-0 and 2-1 transitions of 36ArH+ near 617.5 and 1234.6 GHz, respectively, have been identified very recently as emission lines in spectra obtained with

Discovery of interstellar mercapto radicals (SH) with the GREAT instrument on SOFIA

We report the discovery of interstellar mercapto radicals (SH) along the sight-line to the submillimeter continuum source W49N. We have used the GREAT instrument on SOFIA to observe the 1383 GHz 2

Herschel observations of EXtra-Ordinary Sources (HEXOS): detecting spiral arm clouds by CH absorption lines

We have observed CH absorption lines (J = 3/2, N = 1 <- J = 1/2, N = 1) against the continuum source Sgr B2(M) using the Herschel/HIFI instrument. With the high spectral resolution and wide velocity


We present the detection of rotationally resolved electronic transitions in the OH+ A3Π–X3Σ− (0, 0) and (1, 0) bands toward CD-32 4348, HD 63804, HD 78344, and HD 80077. These four translucent clouds


The rotational spectrum of H2NCO+, the ground-state isomer of protonated HNCO, has been measured in a molecular beam in the centimeter band with a Fourier transform microwave spectrometer and in a

Detection of extragalactic argonium, ArH + , toward PKS 1830-211

Context. Argonium has recently been detected as a ubiquitous molecule in our Galaxy. Model calculations indicate that its abundance peaks at molecular fractions in the range of 10^(-4) to 10^(-3) and

The ionization rates of galactic nuclei and disks from Herschel/HIFI observations of water and its associated ions

Context. Dense gas in galactic nuclei is known to feed central starbursts and AGN, but the properties of this gas are poorly known because of the high obscuration by dust. Aims: Submm-wave



ISO-LWS observations of C+ and O lines in absorption toward SgrB2

High spectral resolution Fabry-P´erot observations of the [O I ] 63.2 and 145.5 µ m and [C II ] 157.7 µ m fine structure lines are presented for the center of the Sagittarius B2 complex (Sgr B2). The

A Molecular Line Survey of Orion KL in the 350 Micron Band

With the Caltech Submillimeter Observatory, we have carried out an unbiased spectral line survey of Orion KL throughout the 350 μm band (from 795 to 903 GHz). This is the first systematic study of

Infrared Space Observatory Long Wavelength Spectrometer Observations of C+ and O0 Lines in Absorption toward Sagittarius B2

High spectral resolution Fabry-Pérot observations of the [O I] 63.2 and 145.5 μm and [C II] 157.7 μm fine-structure lines are presented for the center of the Sagittarius B2 complex (Sgr B2). The data

The line-of-sight distribution of water in the SgrB2 complex

We report the detection, with the Caltech Submillimeter Observatory ? , of the 894-GHz HDO(11;1 00;0) transition, observed in absorption against the background continuum emission of the SgrB2 cores M

The Far-Infrared Spectrum of Arp 220

Infrared Space Observatory Long Wavelength Spectrometer grating observations of the ultraluminous infrared galaxy Arp 220 shows absorption in molecular lines of OH, H2O, CH, NH, and NH3, as well as

Cold atomic gas in the inner Galaxy

A new set of 21 cm H I absorption spectra were obtained toward 21 compact continuum sources in the Galactic plane is presented. The 21 cm line velocity-averaged absorption coefficient as a function

The ISO LWS high-resolution spectral survey towards Sagittarius B2

A full spectral survey was carried out towards the Giant Molecular Cloud complex, Sagittarius B2 (Sgr B2), using the ISO Long Wavelength Spectrometer Fabry-Perot mode. This provided complete

Oxygen isotopic ratios in galactic clouds along the line of sight towards Sagittarius B2

As an independent check on previous measurements of the isotopic abundance of oxygen through the Galaxy, we present a detailed analysis of the ground state rotational lines of 16 OH and 18 OH in

The Atacama Pathfinder EXperiment (APEX) : a new submillimeter facility for southern skies

APEX, the Atacama Pathfinder EXperiment, has been successfully commissioned and is operational. This novel submillimeter telescope is located at 5107 m altitude on Llano de Chajnantor in the Chilean

X-ray chemistry in the envelopes around young stellar objects

We present chemical models of the envelope of a young stellar object (YSO) exposed to a central X-ray source. The models are applied to the massive star-forming region AFGL 2591 for different X-ray