On the occurrence of Hecke eigenvalues in sectors

Abstract

Let $\pi$ be a non-self-dual unitary cuspidal automorphic representation of non-solvable polyhedral type for GL(2) over a number field. We show that $\pi$ has a positive upper Dirichlet density of Hecke eigenvalues in any sector whose angle is at least 2.63 radians.

11 pages. Further details added; subsection 3.3 rewritten