Strategies for scheduling experiments at a Neutron Scattering Facility

Abstract

Strategies for scheduling user experiments taking into consideration reliability issues at a neutron scattering facility were investigated. The facility produces beams of neutrons for experiments in materials science. Ideally, neutron beams produced continuously as scheduled; however, unforeseen outages occur. From data accumulated over a three-year period, a sequence of facility time-on and time-off for a twenty-year period was generated. This sequence was used to test several scheduling strategies for a range of short and long experiments. The tests identified a simple strategy that noticeably increases the chance that a user is able to complete an experiment. The tests were repeated ten times (equivalent to a 200 year period of operation) in order to show the of the study.

Keywords:

• scheduling
• experiments
• shared facility
• breakdowns
• simulation