  To explore the hypothesis that KIC 8462852's aperiodic dimming is caused by
artificial megastructures in orbit (Wright et al. 2015), rather than a natural
cause such as cometary fragments in a highly elliptical orbit (Marengo et al.
2015), we searched for electromagnetic signals from KIC 8462852 indicative of
extraterrestrial intelligence. The primary observations were in the visible
optical regime using the Boquete Optical SETI Observatory in Panama. In
addition, as a preparatory exercise for the possible future detection of a
candidate signal (Heidmann 1991), three of six observing runs simultaneously
searched radio frequencies at the Allen Telescope Array in California. No
periodic optical signals greater than 67 photons/m2 within a time frame of 25
ns were seen. This limit corresponds to isotropic optical pulses of 8E22
joules. If, however, any inhabitants of KIC 8462852 were targeting our solar
system (Shostak & Villard 2004), the required energy would be reduced greatly.
The limits on narrowband radio signals were 180 - 300 Jy Hz at 1 and 8 GHz,
respectively, corresponding to a transmitter with an effective isotropic
radiated power of 4E15 W (and 7E15 W) at the distance of KIC 8462852. While
these powers requirements are high, even modest targeting could - just as for
optical signals - lower these numbers substantially.
