Observation of the X-mode anomalous absorption in the plasma filament associated with the two upper-hybrid-plasmon decayLeanid Simonchik, Alexey Altukhov, Valery Arkhipenko, Alexey Gurchenko, Evgeniy Gusakov, Alexey Popov and Maxim UsachonakEPJ Web Conf., 157 (2017) 03050DOI: https://doi.org/10.1051/epjconf/201715703050