Calciumcyclopropynylidene, CaC₂, is a homolog of MgC₂ and somewhat related to silacyclopropynylidene, SiC₂.
H. Gupta, P. B. Changala, J. Cernicharo, J. R. Pardo, M. Agúndez, C. Cabezas, B. Tercero, M. Guélin, and M. C. McCarthy
reported on the
Calcium Chemistry in Carbon-rich Circumstellar Environments: The Laboratory and Astronomical Discovery of Calcium Dicarbide, CaC₂
Astrophys. J. Lett 966, Art. No. L28 (2024).
Ten a-type lines with 1 ≤ J ≤ 7 and K_a ≤ 4 between 41 and 150 GHz were identified for the main ²⁴Mg isotopolog employing the Yebes 40 m and IRAM 30 m dishes in the couses of molecular line surveys of CW Leonis. These lines have good to reasonable signal-to-noise ratios, and several lines are unblended. One and three lines were identified for the ²⁵Mg and ²⁶Mg minor isotopologs, respectively. The isotopic ratios are compatible with solar values within uncertainties. The derived MgC₂ : MgC₂H : MgC₄H : MgC₆H abundance raios are about 1 : 2 : 22 : 20.

Contributor(s): H. S. P. Müller; 05, 2024