All the $\lambda_1$'s on cyclic admissible covers

Abstract

We compute the degree of Hurwitz-Hodge classes $\lambda_1^e$ on one dimensional moduli spaces of cyclic admissible covers of the projective line. We also compute the degree of the the first Chern class of the Hodge bundle $\lambda_1$ for all one dimensional moduli spaces. In higher dimension, we express the divisor class $\lambda_1$ as a linear combination of $\psi$ classes and boundary strata.