Joint experimental team, E17 lead by Professor Ryugo Hayano, University of Tokyo and E15, lead by Dr. Masahiko Iwasaki, Riken, has successfully confirmed kaon generation in the secondary beams at the K1.8BR, Hadron Facility, J-PARC. This result was reported by Dr. Takatoshi Suzuki, University of Tokyo, at "Workshop Celebrating the First Beam at Hadron Hall" held on March 25-26 at Tokai.

After the termination of the operation in JFY2008, they continued to analyze the recorded data very carefully. After adjusting time offsets between counter segments and correcting the time jitters due to signal height etc, as usually performed in high-energy experiments, the time of flight resolution was much improved. Then kaons can be identified in the improved time-of-flight spectrum shown in figure.1.

The quantity of kaons is about 1/500 of that of pions, consistent with the expected value for un-separated beam condition without the operation of the Electro-Static separator operation. The Electro-Static separator is designed to improve the kaon/pion yield ratio to be 1 or more. This confirmation of the kaon generation is a big step forward to utilize kaon beam at the hadron facility.

Figure 1  :  Improved time of flight spectrum.