1. A user apparatus that communicates with a base station in a mobile communication system, comprising:a reception unit configured to receive a radio signal from the base station by a downlink control channel; and
a control information detection unit configured to detect control information, addressed to the user apparatus, mapped to a predetermined area in a time frequency resource of the downlink control channel by performing blind decoding in a plurality of candidate areas which are candidates of the predetermined area,
wherein the mobile communication system communicates using dual connectivity, and
wherein the control information detection unit performs the blind decoding in areas in which a part of areas is excluded from the plurality of candidate areas based on configuration information from a master base station (MeNB) of a plurality of base stations in the dual connectivity.