Ultrarelativistic magnetic monopole search with the ANITA-II balloon-borne radio interferometer

Abstract

We have conducted a search for extended energy deposition trails left by ultrarelativistic magnetic monopoles interacting in Antarctic ice. The nonobservation of any satisfactory candidates in the 31 days of accumulated ANITA-II (Antarctic Impulsive Transient Antenna) flight data results in an upper limit on the diffuse flux of relativistic monopoles. We obtain a 90% C.L. limit of order 10⊃-19(cm2ssr)⊃-1 for values of Lorentz factor, γ, 1010≤γ at the anticipated energy Etot=1016GeV. This bound is stronger than all previously published experimental limits for this kinematic range. © 2011 The American Physical Society.