Kato-Usui partial compactifications over the toroidal compactifications of Siegel spaces

摘要

We construct fans which give Kato-Usui partial compactifications of perioddomains of weight -1. Similarly to the fans of toroidal compactifications,these fans are given by polyhedral decompositions. We also show a fibrationstructure for some kind of Kato-Usui boundary components.