Astronomical Detection of the Interstellar Anion C10H− toward TMC-1 from the GOTHAM Large Program on the Green Bank Telescope

Using data from the Green Bank Telescope (GBT) Observations of TMC-1: Hunting for Aromatic Molecules (GOTHAM) survey, we report the first astronomical detection of the C10H− anion. The astronomical observations also provided the necessary data to refine the spectroscopic parameters of C10H−. From the velocity stacked data and the matched filter response, C10H− is detected at >9σ confidence level at a column density of 4.04−2.23+10.67×1011 cm−2. A dedicated search for the C10H radical was also conducted toward TMC-1. In this case, the stacked molecular emission of C10H was detected at a ∼3.2σ confidence interval at a column density of 2.02−0.82+2.68×1011 cm−2. However, as the determined confidence level is currently