Research Director's Report
17 July 2008
My tribute to Yoji
Arriving at DESY last Thursday, I heard the sad news of Yoji from home. This reminded me of the most enjoyable days I had in physics with him here at DESY in the Double-Arm Spectrometer (DASP) group lead by Björn Wiik and Guenter Wolf. When Prof. Masatoshi Koshiba decided to join the e+e- collision experiment by participating in the DASP collaboration, he first sent Yoji to DESY just before Christmas in 1972. I joined him half a year later, after my ten-month stay in Novosibirsk. Another half a year later Teruhiro Suda, who later became one of the first members of Kamiokande group to build it, arrived and we worked for the inner detector of DASP with colleagues from the University of Hamburg and DESY. Yoji and Teruhiro constructed its proportional tube counters for tracking. When DORIS began operation in 1974, the big news of the sharp peak at 3.1 GeV came from the US. The inner detector, which was the only detector available that time, could confirm the peak in Bhabha scattering as the machine hit the right energy. This was the start of an extremely exiting period which Yoij and I shared together with many friends at DESY. He stayed in Hamburg until he finished the construction of his part of the JADE detector. Then he went back to Tokyo to support logistics at home, which was crucial to conduct an international collaboration. This gave him a chance to do different physics at home and, maybe persuaded by Prof. Koshiba, Yoji joined Kamiokande and later resulted to lead Super-Kamiokande. Nevertheless, he kept his interest and sympathy for e+e- - physics. This was why he spent much effort for ILC years later when he served as the director general of KEK.
Not only the particle physics community but also cosmic ray physics and astrophysics communities lost a brilliant physicist and leader. I also lost one of the best friends from my graduate-student days. We had many experiences together since then even when we worked in somewhat different fields.
-- Sakue Yamada