Chemical exchange saturation transfer effects are enhanced by forming, for each of a plurality of magnetization transfer offset frequencies within a specified first range, a respective image representing CEST effects. Another object of the present invention is to realize RTP communication for establishing sessions in accordance with SIP between an IPv6 terminal connected to an IPv6 network and an IPv4 terminal connected to an IPv4 network. An annular groove is provided on a top tube of the shaft of the umbrella.