# Discovery of the first Ca-bearing molecule in space: CaNC

## TL;DR

This paper reports the first detection of calcium isocyanide (CaNC) in space, specifically in the star IRC+10216, revealing new insights into metal-bearing molecules in stellar environments.

## Contribution

The discovery of CaNC in space and the analysis of its abundance and formation region in the circumstellar envelope are novel contributions.

## Key findings

- CaNC detected with a column density of (2.0±0.5)×10^{11} cm^{-2}
- CaNC is produced in the intermediate and outer envelope layers
- Abundance ratio of CaNC to MgNC is approximately 1/60, and to FeCN is about 1.

## Abstract

We report on the detection of calcium isocyanide, CaNC, in the carbon-rich evolved star IRC+10216. We derived a column density for this species of (2.0$\pm$0.5)$\times$10$^{11}$ cm$^{-2}$. Based on the observed line profiles and the modelling of its emission through the envelope, the molecule has to be produced in the intermediate and outer layers of the circumstellar envelope where other metal-isocyanides have previously been found in this source. The abundance ratio of CaNC relative to MgNC and FeCN is $\simeq$1/60 and $\simeq$1, respectively. We searched for the species CaF, CaCl, CaC, CaCCH, and CaCH$_3$ for which accurate frequency predictions are available. Only upper limits have been obtained for these molecules.