Cancellation of 2013A Beamtime and New Deadline for 2013B Proposals

18 June 2013

Dear MLF Users,

You will all by now be aware of the accident that occurred at the Hadron Experimental Facility of J-PARC on 23 May 2013 that resulted in radioactive material leaking into the Hadron Hall and the external environment. Following the accident, there was a regrettably long delay in reporting the incident to local authorities and relevant government agencies due to time spent investigating and checking the circumstances of the accident and then determining the appropriate course of action.

We take this opportunity to express our sincere apologies to the wider MLF community for the trouble and concern that were caused by these events and our failure to act in a timely manner in response. J-PARC Center feels very strongly not only social, but also moral responsibility for this accident that should never have been allowed to happen within our facility.

In order to regain the trust that has been lost, we are now striving to uncover the causes of the accident and, going back to basics, will develop and implement measures to prevent a recurrence of such an incident. Under the guidance of relevant government agencies and, in close collaboration with JAEA and KEK, we are working towards restoring confidence in the facility as soon as possible.

The top priority for J-PARC Center at the present time is the investigation of the accident, the completion of a full safety review and the preparation of new policies and procedures to prevent such an accident happening again. To facilitate these activities, operations at all J-PARC facilities have been suspended until further notice.

Accordingly, MLF beamtime that was scheduled to be available until the end of July 2013 will no longer be offered and, as a result, it will not be possible to accommodate 2013A neutron and muon proposals that had been approved for this period.

Please note that there will be no 'carry over' of any 2013A proposals that were approved but not carried out as a result of the circumstances described above. All affected users are encouraged to apply again for beamtime by submitting a proposal in a future round. In this regard, we advise that the 2013B proposal submission deadline, that had been postponed indefinitely, has now been set for 17:00 (JST) on Monday 8 July 2013.

To be clear, it is not known at the present time if the 2013B operations period will go ahead as scheduled. This will depend on the outcome of the accident investigation and, I must emphasize, will be possible only after we obtain the approval of relevant authorities and the Japanese public.

We understand that these developments will cause disruption and inconvenience for the entire MLF user community but ask for your understanding as we work through this difficult period.

Yours sincerely,

Masatoshi Arai (Head, MLF Division, J-PARC Center)