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arXiv · 1803.05442

Detection of HOCO+ in the protostar IRAS 16293-2422

Liton Majumdar·Pierre Gratier·Valentine Wakelam·Emmanuel Caux·Karen Willacy·Michael E. Ressler
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Abstract

The protonated form of CO2, HOCO+, is assumed to be an indirect tracer of CO2 in the millimeter/submillimeter regime since CO2 lacks a permanent dipole moment. Here, we report the detection of two rotational emission lines (4 0,4-3 0,3) and (5 0,5-4 0,4) of HOCO+ in IRAS 16293-2422. For our observations, we have used EMIR heterodyne 3 mm receiver of the IRAM 30m telescope. The observed abundance of HOCO+ is compared with the simulations using the 3-phase NAUTILUS chemical model. Implications of the measured abundances of HOCO+ to study the chemistry of CO2 ices using JWST-MIRI and NIRSpec are discussed as well.

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Liton Majumdar, Pierre Gratier, Valentine Wakelam, Emmanuel Caux, Karen Willacy, Michael E. Ressler. 2018-03-14. Detection of HOCO+ in the protostar IRAS 16293-2422. https://doi.org/10.1093/mnras%2Fsty703

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