Values of Twisted Tensor L-functions of Automorphic Forms Over Imaginary Quadratic Fields

摘要

Let K be a complex quadratic extension of Q and let A_K denote the adeles of K. We find special values at all of the critical points of twisted tensor L-functions attached to cohomological cuspforms on GL_2(A_K) and establish Galois equivariance of the values. To investigate the values, we determine the archimedean factors of a class of integral representations of these L-functions, thus proving a conjecture due to Ghate. We also investigate analytic properties of these L-functions, such as their functional equations.