Detection of HOCO+ in the protostar IRAS 16293-2422

TL;DR

This paper reports the first detection of HOCO+ in the protostar IRAS 16293-2422, using IRAM 30m telescope observations, and discusses its implications for understanding CO2 ice chemistry.

Contribution

First detection of HOCO+ in a protostar, linking observations with chemical models and future JWST studies.

Findings

Detected two rotational lines of HOCO+ in IRAS 16293-2422.

Compared observed HOCO+ abundance with chemical model simulations.

Discussed implications for CO2 ice chemistry studies with JWST.

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.