Regular poles for spinor L-series attached tosplit Bessel models of GSp(4)

For irreducible smooth representations of GSp(4, k) over a nonarchimedean local field k, Piatetski-Shapiro and Soudry (1981) have constructed an L-factor depending on the choice of a Bessel model.It factorizes into a regular part and an exceptional part.We determine the regular part for the case of split Bessel models.1. Introduction 137 2. Representations of Gl a (1) 142 3. Representations of affine linear groups in general 152 4. Siegel induced representations 166 5. Main results