The Spin $L$-function on $\mathrm{GSp}_6$ via a non-unique model

TL;DR

This paper constructs two global integrals for the Spin $L$-function on $ ext{GSp}_6$, revealing its analytic properties and connection to exceptional theta lifts, extending prior work on special cases.

Contribution

It introduces two new global integrals representing the Spin $L$-function on $ ext{GSp}_6$, generalizing previous results to broader classes of automorphic representations.

Findings

Partial Spin $L$-function is holomorphic except possibly at $s=1$

Pole at $s=1$ indicates an exceptional theta lift from $ ext{G}_2$

Extension of previous work to non-unique models

Abstract

We give two global integrals that unfold to a non-unique model and represent the partial Spin $L$-function on $\mathrm{GSp}_6$. We deduce that for a wide class of cuspidal automorphic representations $\pi,$ the partial Spin $L$-function is holomorphic except for a possible simple pole at $s=1$, and that the presence of such a pole indicates that $\pi$ is an exceptional theta lift from $\mathrm{G}_2$. These results utilize and extend previous work of Gan and Gurevich, who introduced one of the global integrals and proved these facts for a special subclass of these $\pi$ upon which the aforementioned model becomes unique. The other integral can be regarded as a higher rank analogue of the integral of Kohnen-Skoruppa on $\mathrm{GSp}_4$.