Recognition by spectrum for simple classical groups in characteristic 2

Abstract

A finite group G is said to be recognizable by spectrum if every finite group with the same set of element orders as G is isomorphic to G. We prove that all finite simple symplectic and orthogonal groups over fields of characteristic 2, except S4(q), S6(2), O8+ (2), and S8(q), are recognizable by spectrum. This result completes the study of the recognition-by-spectrum problem for finite simple classical groups in characteristic 2.