Koecher-Maass series of a certain half-integral weight modular form related to the Duke-Imamoglu-Ikeda lift

TL;DR

This paper derives an explicit formula for the Koecher-Maass series of a specific half-integral weight modular form related to the Duke-Imamoglu-Ikeda lift, connecting it to L-functions of associated forms.

Contribution

It provides a new explicit formula for the Koecher-Maass series of a certain half-integral weight modular form linked to the Duke-Imamoglu-Ikeda lift, expanding understanding of their L-function relationships.

Findings

Explicit Koecher-Maass series formula derived

Connection established between series and L-functions of h and f

Enhances understanding of modular forms related to Duke-Imamoglu-Ikeda lift

Abstract

Let k and n be positive even integers. For a cuspidal Hecke eigenform h in the Kohnen plus space of weight k-n/2+1/2, let f be the corresponding primitive form of weight 2k-n for SL(2,Z) under the Shimura correspondence, and I(h) the Duke-Imamoglu-Ikeda lift of h to the space of cusp forms of weight k of genus n. Moreover, let FJ(I(h),1) be the first Fourier-Jacobi coefficient of I(h) and s(FJ(I(h),1)) be the cusp form in the generalized Kohnen plus space of weight k-1/2 corresponding to FJ(I(h),1) under the Ibukiyama isomorphism. We then give an explicit formula for the Koecher-Maass series of s(FJ(I(h),1)) expressed in terms of the usual L-functions of h and f.