English

A Fourier-Jacobi Dirichlet series for cusp forms on orthogonal groups

Number Theory 2025-09-22 v2

Abstract

We investigate a Dirichlet series involving the Fourier-Jacobi coefficients of two cusp forms F,GF,G for orthogonal groups of signature (2,n+2)(2,n+2). In the case when FF is a Hecke eigenform and GG is a Maass lift of a Poincar\'e series, we establish a connection with the standard LL-function attached to FF. What is more, we find explicit choices of orthogonal groups, for which we obtain a clear-cut Euler product expression for this Dirichlet series. Through our considerations, we recover a classical result for Siegel modular forms, first introduced by Kohnen and Skoruppa, but also provide a range of new examples, which can be related to other kinds of modular forms, such as paramodular, Hermitian, and quaternionic.

Keywords

Cite

@article{arxiv.2407.18663,
  title  = {A Fourier-Jacobi Dirichlet series for cusp forms on orthogonal groups},
  author = {Rafail Psyroukis},
  journal= {arXiv preprint arXiv:2407.18663},
  year   = {2025}
}

Comments

31 pages, accepted version in "Research in Number Theory"

R2 v1 2026-06-28T17:54:29.522Z