High power conditioning of the DTL for J-PARC

The high-power conditioning of the three DTL tanks for the J-PARC has been started in October 2006. The design rf peak-power levels for beam acceleration of the tanks are about 1.1 MW (DTL1), 1.2 MW (DTL2) and 1.0 MW (DTL3), respectively. As a result of the conditioning, we have achieved that the rf power levels are about 1.3 MW, 1.45 MW and 1.23 MW of which are 1.2 times the power levels of the desired one (the pulse length is 650 mus and the pulse repetition is 25 Hz). During the linac beam commissioning, the DTLs can keep the required rf power stable now.