Let F be a cuspidal Hermitian eigenform of degree two over ℚ(i), with first Fourier-Jacobi coefficient not identically zero. Building on a paper by Das and Jha, we prove the meromorphic continuation to ℂ and the functional equation of a degree six L-function attached to F by Gritsenko, twisted by a Dirichlet character.
Rafail Psyroukis (Fri,) studied this question.