M. A. Siebert, K. L. K. Lee, A. J. Remijan, A. M. Burkhardt, The GOTHAM Collaboration, R. A. Loomis, M. C. McCarthy, and B. A. McGuire
reported on the
CH3-Terminated Carbon Chains in the GOTHAM Survey of TMC-1: Evidence of Interstellar CH₃C₇N
Astrophys. J. 924 (2022), Art. No. 21.
The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the ¹⁴N hyperfine structure splitting. Methylcyanotriacetylene, aka cyanoheptatriyne, was indentified through line-stacking with a signal-to-noise ratio that was slightly below the 5σ level deemed to be required for a secure detection, and thus viewed as a tentative detection. The derived low excitation temperature and the column density appear to be in line with trends from methylcyanoacetylene and methylcyanodiacetylene.

Contributor(s): H. S. P. Müller; 03, 2022