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arXiv · 1305.3915

H3+ Spectroscopy and the Ionization Rate of Molecular Hydrogen in the Central Few Parsecs of the Galaxy

M. Goto·Nick Indriolo·T. R. Geballe·T. Usuda
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Abstract

We report observations and analysis of infrared spectra of H3+ and CO lines in the Galactic center, within a few parsecs of the central black hole, Sgr A*. We find a cosmic ray ionization rate typically an order of magnitude higher than outside the Galactic center. Notwithstanding, the elevated cosmic ray ionization rate is 4 orders of magnitude too short to match the proton energy spectrum as inferred from the recent discovery of the TeV gamma-ray source in the vicinity of Sgr A*.

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M. Goto, Nick Indriolo, T. R. Geballe, T. Usuda. 2013-05-16. H3+ Spectroscopy and the Ionization Rate of Molecular Hydrogen in the Central Few Parsecs of the Galaxy. https://doi.org/10.1021/jp400017s

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