Branched covers and pencils on hyperelliptic Lefschetz fibrations

Abstract: Generalizing work of I. Baykur, K. Hayano, and N. Monden (arXiv:1903.02906), we construct infinite families of symplectic 4-dimensional manifolds, obtained as total spaces of Lefschetz pencils constructed by explicit monodromy factorizations. Then, generalizing work of the author (arXiv:2108.04868), we show that each of these manifolds is diffeomorphic to a complex surface that is a fiber sum formed from two standard examples of hyperelliptic Lefschetz fibrations. Consequently, we see that these hyperelliptic Lefschetz fibrations, as well as all fiber sums of them, admit an infinite family of explicitly described Lefschetz pencils, which we observe are different from families formed by the degree doubling procedure.