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arXiv · 1910.03711

Breakthrough Listen Follow-up of the Random Transiter (EPIC 249706694/HD 139139) with the Green Bank Telescope

Bryan Brzycki·Andrew P. V. Siemion·Steve Croft·Daniel Czech·David DeBoer·Julia DeMarines·Jamie Drew·J. Emilio Enriquez·Vishal Gajjar·Nectaria Gizani·Howard Isaacson·Brian C. Lacki·Matt Lebofsky·David H. E. MacMahon·Imke de Pater·Daniel C. Price·Sofia Z. Sheikh·Claire Webb·S. Pete Worden
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Abstract

The star EPIC 249706694 (HD 139139) was found to exhibit 28 transit-like events over an 87 day period during the Kepler mission's K2 Campaign 15 (Rappaport et al. 2019). These events did not fall into an identifiable pattern and could not be explained by a multitude of transit scenarios explored by the authors. We conduct follow-up observations at C-band frequencies with the Green Bank Telescope as part of the ongoing Breakthrough Listen search for technosignatures. We search for narrow band signals above a signal-to-noise threshold of 10 and with Doppler drift rates within +-5 Hz/s. We detect no evidence of technosignatures from EPIC 249706694 and derive an upper limit for the EIRP (Equivalent Isotropic Radiated Power) of putative transmissions to be 10 TW.

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Bryan Brzycki, Andrew P. V. Siemion, Steve Croft, Daniel Czech, David DeBoer, Julia DeMarines, Jamie Drew, J. Emilio Enriquez, Vishal Gajjar, Nectaria Gizani, Howard Isaacson, Brian C. Lacki, Matt Lebofsky, David H. E. MacMahon, Imke de Pater, Daniel C. Price, Sofia Z. Sheikh, Claire Webb, S. Pete Worden. 2019-10-08. Breakthrough Listen Follow-up of the Random Transiter (EPIC 249706694/HD 139139) with the Green Bank Telescope. https://arxiv.org/abs/1910.03711

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