Toroidal families and averages of L-functions, I

We initiate the study of certain families of L-functions attached to characters of subgroups of higher-rank tori, and of their average at the central point. In particular, we evaluate the average of the values L( 2 1 , chi a )L( 21 , chi b ) for arbitrary integers a and b when chi varies over Dirichlet characters of a given prime modulus.