Status of the KEKB project

KEKB, KEK B-Factory, is an asymmetric energy, two-ring, electron-positron collider for B-physics and is now under construction at KEK. Machine study done at the accumulation ring, AR, of TRISTAN, in 1996 showed that HOM-free normal-conducting cavities, called ARES, and superconducting, single-cell, single-mode cavities being developed could be used for KEKB. The fast beam-ion instability was also studied experimentally. Installation of equipment in the tunnel started in February 1997. Commissioning of the machine will start from the upgraded injector linac in May 1998 to the two rings in October 1998. We anticipate beam collision toward the end of the year, which will be followed by the start of physics experiments in early 1999.