The Fourth Moment of Dirichlet L-Functions for the Rational Function   Field
  We study the moments of the Dirichlet L-function when defined over the polynomial ring over finite fields. We find an asymptotic formula to the fourth moment of the central value of Dirichlet L functions in this context. We also find a lower bound to the 2kth moment of these L-functions. 
Nattalie Tamam
math.NT