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Related papers: HOCO+ toward the Galactic Center

200 papers

We present 44 and 226 GHz observations of the Galactic center within 20$"$ of Sgr A*. Millimeter continuum emission at 226 GHz is detected from eight stars that have previously been identified at near-IR and radio wavelengths. We also…

High Energy Astrophysical Phenomena · Physics 2017-08-02 F. Yusef-Zadeh , R. Schödel , M. Wardle , H. Bushouse , W. Cotton , M. J. Royster , D. Kunneriath , D. A. Roberts , E. Gallego-Cano

The cosmic-ray ionization rate (zeta) of dense molecular clouds is a key parameter for their dynamics and chemistry. Variations of zeta are well established, but it is unclear if these are related to source column density or to Galactic…

We present new observations of HCN and HCO+in the circumnuclear disk (CND) of the Galaxy, obtained with the APEX telescope. We have mapped emission in rotational lines of HCN J = 3-2, 4-3, and 8-7, as well as HCO+ J = 3-2, 4-3, and 9-8. We…

Astrophysics of Galaxies · Physics 2015-06-17 Elisabeth A. C. Mills , Rolf Güsten , Miguel A. Requena Torres , Mark R. Morris

This paper reports the diffuse X-ray features around the Galactic center observed with Chandra. We confirm the ASCA and Ginga discoveries of the large-scale thin-thermal plasma with strong lines in the Galactic center region. In addition,…

The results of a CO line survey in central cluster galaxies with cooling flows are presented. Cold molecular gas is detected with the IRAM 30m telescope, through CO(1-0) and CO(2-1) emission lines in 6-10 among 32 galaxies. The…

Astrophysics · Physics 2009-11-10 P. Salome , F. Combes

We present J=2-1, J=3-2, J=4-3 12CO maps as well as J=2-1, J=3-2 13CO and 492 GHz [CI] measurements of the central region in M51. The distribution of CO is strongly concentrated towards the spiral arms. The center itself is poor in, though…

Astrophysics · Physics 2009-11-11 F. P. Israel , R. P. J. Tilanus , F. Baas

We investigate the molecular gas properties of a sample of 23 galaxies in order to find and test chemical signatures of galaxy evolution and to compare them to IR evolutionary tracers. Observation at 3 mm wavelengths were obtained with the…

(Abridged) The goal of this work is to investigate if SiO, H2O and HCN maser emission within the ALMA frequency range can be detected with observable levels of fractional linear polarization in the regime where the Zeeman frequency (gOmega)…

Solar and Stellar Astrophysics · Physics 2015-06-12 A. F. Pérez-Sánchez , W. H. T. Vlemmings

We present a systematic study of the HNCO, C18O, 13CS, and C34S emission towards 13 selected molecular clouds in the Galactic center region. The molecular emission in these positions are used as templates of the different physical and…

Astrophysics · Physics 2009-11-13 S. Martin , M. A. Requena-Torres , J. Martin-Pintado , R. Mauersberger

CO(2-1) emission is often used as a tracer of the giant molecular clouds (GMCs) as an alternative to CO(1-0) emission in recent years. Therefore, understanding the environmental dependence of the line ratio of CO(2-1)/CO(1-0), $R_{21}$, on…

Astrophysics of Galaxies · Physics 2022-02-23 Fumiya Maeda , Fumi Egusa , Kouji Ohta , Yusuke Fujimoto , Asao Habe , Yoshihisa Asada

We present a synthesis of a number of recent observations in the near-IR H_2 and [Fe II] lines, OH (1720 MHz) maser line and various radio continuum measurements using the NICMOS of the HST, UNSWIRF on the AAT and the VLA. These…

Astrophysics · Physics 2007-05-23 F. Yusef-Zadeh , S. Stolovy , M. Burton , M. Wardle , F. Melia , J. Lazio , N. Kassim

We present the results of SiO (2-1) and SO2 (12-13) line observations of Sgr B2(N) made with the Atacama Large Millimeter/submillimeter Array (ALMA) at an angular resolution of ~2arcsec. Our analysis of the SiO and SO2 line emission reveals…

Astrophysics of Galaxies · Physics 2015-12-23 Aya E. Higuchi , Tetsuo Hasegawa , Kazuya Saigo , Patricio Sanhueza , James O. Chibueze

We present Submillimeter Array observations of H2CO and N2H+ emission in the disks around the T Tauri star TW Hya and the Herbig Ae star HD 163296 at 2"-6" resolution and discuss the distribution of these species with respect to CO…

Astrophysics of Galaxies · Physics 2015-06-12 Chunhua Qi , Karin Oberg , David Wilner

The H3O+ molecule probes the oxygen chemistry and the ionization rate of dense circumnuclear gas in galaxies. In particular, recent H3O+ observations show variations in the cosmic-ray ionization rate by factors of $>$10 within our Galaxy.…

Astrophysics · Physics 2009-11-13 Floris van der Tak , Susanne Aalto , Rowin Meijerink

We report the detection of the CO(12-11) line emission toward G09-83808 (or H-ATLAS J090045.4+004125), a strongly-lensed submillimeter galaxy at $z = 6.02$, with Atacama Large Millimeter/submillimeter Array observations. Combining…

Continuum low-frequency radio observations of the Galactic Center reveal the presence of two prominent radio sources, Sgr A East and its surrounding Halo, containing non-thermal particle distributions with power-law indices around 2.5-3.3…

Astrophysics · Physics 2009-10-30 Fulvio Melia , Farhad Yusef-Zadeh , Marco Fatuzzo

Observations of the molecular gas in galaxies are vital to understanding the evolution and star-forming histories of galaxies. However, galaxies with molecular gas maps of their whole discs having sufficient resolution to distinguish…

(Abridged) We present fine structure and recombination lines observations of the ionized gas toward a sample of 18 sources located within 300 pc of the center of the Galaxy (GC). The fine structure lines from [NII] and [SIII] have been…

Astrophysics · Physics 2009-11-10 N. J. Rodriguez-Fernandez , J. Martin-Pintado

We have surveyed the central molecular zone (CMZ) of our Galaxy in the CO J=3-2 line with the Atacama Submillimeter-wave Telescope Experiment (ASTE). Molecular gas in the Galactic center shows high J=3-2/J=1-0 intensity ratio (~ 0.9) while…

Astrophysics · Physics 2015-06-24 Tomoharu Oka , Makoto Nagai , Kazuhisa Kamegai , Kunihiko Tanaka , Nobuyuki Kuboi

We present near-infrared and millimetre-line observations of the Tornado nebula (G357.7-0.1). We detected 2.12 micron_m H2 1-0 S(1) line emission towards the suspected site of interaction with a molecular cloud revealed by the presence of…

Astrophysics · Physics 2009-11-10 J. S. Lazendic , M. Wardle , M. G. Burton , F. Yusef-Zadeh , A. J. Green , J. B. Whiteoak