Dear colleague,

As a director of the Kamioka Observatory, which owns and is responsible to operate and maintain the Super-Kamiokande detector, it is really sad that I have to announce the severe accident that occurred on November 12 and damaged the significant part of the detector. We would like to express our deep regret to Japanese, US and Korean people who have generously supported the Super-Kamiokande experiment. The cause and how to deal with the loss in future will be discussed by newly founded committees. However, even before discussing with my colleagues of the Super-K and K2K collaborations, I have decided to express my intention on behalf of the staff of the Kamioka Observatory.

We will rebuild the detector. There is no question. The strategy may be the following two steps, which will be proposed and discussed among my colleagues.

1. Quick restart of the K2K experiment.
(1) We will clear the safety measures which may be suggested by the committees, (2) reduce the number density of the photomultiplier tubes by about a half, (3) use the existing resources, (4) resume the K2K experiment as soon as possible; the goal may be within one year.

2. Preparation for the JHF-Kamioka experiment.
(1) Restore the full Super-Kamiokande detector armed with the state-of-the-art techniques. (2) The detector will be ready by the time of the commissioning of the JHF machine.

Needless to say, we will be able to study atmospheric neutrinos and search for proton decay with the step-1 detector. We will be able to maintain our watch for supernova with a somewhat higher-energy threshold.

To achieve our objective is formidable but we are determined to do so. We certainly need your encouragement, advice and help. I should appreciate it very much if you could support our effort as you have kindly done so before.


Best regards,
Yoji Totsuka
director, Kamioka Observatory
On behalf of the Kamioka Observatory staff