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H2 emission from CRL 618

F. Herpin·J. Cernicharo·A. Heras
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Abstract

We present a complete study of the H2 infrared emission, including the pure rotational lines, of the proto Planetary Nebulae CRL 618 with the ISO SWS. A large number of lines are detected. The analysis of our observations shows: (i) an OTP ratio very different from the classical value of 3, probably around 1.76-1.87; (ii) a stratification of the emitting region, and more precisely different regions of emission, plausibly located in the lobes, in an intermediate zone, and close to the torus; (iii) different excitation mechanisms, collisions and fluorescence.

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F. Herpin, J. Cernicharo, A. Heras. 2000-01-03. H2 emission from CRL 618. https://arxiv.org/abs/astro-ph/0001017

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