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XDR Chemistry in the Circumnuclear Disk of NGC 1068

A. Usero·S. Garcia-Burillo·A. Fuente·J. Martin-Pintado
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Abstract

We have studied the feedback influence that the central engine of the Seyfert 2 galaxy NGC 1068 may have on the chemistry of the 200 pc circumnuclear gas disk (CND). With this purpose, we have conducted a multi-species/multi-transition survey of molecular gas in the CND of NGC 1068 using the IRAM 30m telescope. Abundances of several molecular species have been estimated, including HCN, CN, CS, HCO+, SiO and HOC+. We report on the detection of significant SiO emission in this galaxy, as well as on the first extragalactic detection of the active radical HOC+. We conclude that the chemistry of the molecular gas reservoir in the CND can be best explained in the framework of X-rays Dominated Regions (XDR) models.

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A. Usero, S. Garcia-Burillo, A. Fuente, J. Martin-Pintado. 2003-10-28. XDR Chemistry in the Circumnuclear Disk of NGC 1068. https://arxiv.org/abs/astro-ph/0310783

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