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arXiv · 1803.10187

Search for OH 18-cm radio emission from 1I/2017 U1 with the Green Bank telescope

Ryan S. Park·D. J. Pisano·T. Joseph W. Lazio·Paul W. Chodas·Shantanu P. Naidu
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Abstract

This paper reports the first OH 18-cm line observation of the first detected interstellar object 1I/2017 U1 (`Oumuamua) using the Green Bank Telescope. We have observed the OH lines at 1665.402 MHz, 1667.359, and 1720.53 MHz frequencies with a spectral resolution of 357 Hz (approximately 0.06 km-s^{-1}). At the time of the observation, `Oumuamua was at topocentric distance and velocity of 1.07 au and 63.4 km-s^{-1}, respectively, or at heliocentric distance and velocity of 1.8 au and 39 km-s^{-1}, respectively. Based on a detailed data reduction and an analogy-based inversion, our final results confirm the asteroidal origin of `Oumuamua (as discussed in Meech et al., 2017) with an upper bound of OH production of Q[OH] < 0.17 x 10^{28} s^{-1}.

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Ryan S. Park, D. J. Pisano, T. Joseph W. Lazio, Paul W. Chodas, Shantanu P. Naidu. 2018-03-27. Search for OH 18-cm radio emission from 1I/2017 U1 with the Green Bank telescope. https://doi.org/10.3847/1538-3881%2Faab78d

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