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arXiv · 2105.03510

Detection of OH 18-cm Emission from Comet C/2020 F3 NEOWISE using the Arecibo Telescope

Allison J. Smith·D. Anish Roshi·Periasamy Manoharan·Sravani Vaddi·Benetge B. P. Perera·Anna McGilvray
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Abstract

We report the detection of emission from the OH 18 cm $\Lambda$-doublet transitions toward Comet C/2020 F3 NEOWISE using the Arecibo Telescope. The antenna temperatures are 113$\pm$3 mK for the 1667 MHz line and 57$\pm$3 mK for the 1665 MHz line. The beam averaged OH column density (centered on the comet nucleus) derived from the 1667 transition is $N_{OH}$=1.11$\pm0.06\times10^{13}$ cm$^{-2}$. We implemented the Haser model to derive an OH production rate. The estimated OH production rate using the 1667 MHz transition is Q$_{OH}$=3.6$\pm0.6\times10^{28}$ s$^{-1}$, a factor of 2.4 lower than optically derived values for the same observing day, the difference of which is likely explained by quenching.

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Allison J. Smith, D. Anish Roshi, Periasamy Manoharan, Sravani Vaddi, Benetge B. P. Perera, Anna McGilvray. 2021-05-07. Detection of OH 18-cm Emission from Comet C/2020 F3 NEOWISE using the Arecibo Telescope. https://arxiv.org/abs/2105.03510

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