DEGREE 16 STANDARD L-FUNCTION OF GSP(2)XGSP(2) - INTRODUCTION

By the doubling method; we have constructed a global integral of Ranki n-Selberg type, which has been proved to represent the degree 16 stand ard L-function of GSp(2) x GSp(2), where GSp(2) is the rank two group of symplectic similitudes. After our determination of the location and the degree of the possible poles of a family of Eisenstein series, wh ich is involved in the global convolution, and our establishing of two first term identities in the sense of Kudla-Rallis, the analytic prop erties of the global integral are completely determined. The local the ory of Rankin-Selberg convolution is also developed, but over the arch imedean field, the Local theory has not been completed as yet. This pa rt together with the applications of the L-function to automorphic rep resentation theory and number theory will be included in our future wo rks.