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Critical Beam Change Request

Requests for a critical beam change require review by the ATLAS safety committees. Critical beam changes include requests for:

  • increment in maximum beam energy or intensity
  • use of different end station
  • use of different beam species
  • beam time extension/reduction

Please submit your review requests for a critical beam change by completing the Critical Beam Change Request Form.

Scheduling Process

Scheduling Considerations

The ATLAS schedule is developed with the goals of optimizing the productive use of beam time while allowing for proper facility staffing and maintenance.

  • Beamtime at ATLAS is normally scheduled in two-month blocks.
  • During periods of 7-day-per-week operations, no new experiments will start and no change of beam species will occur over weekends. In addition, the number of new beam tunes (i.e., experiment starts) on Fridays will be kept to a minimum. 
  • Every effort will be made to conduct required and emergency maintenance in a way that minimizes impact on the experimental program.
  • Every effort will be made to minimize conflicts between experiments.
  • Experiments using similar equipment and/or the same beam species will be scheduled sequentially whenever possible unless it places undue burden on one or more of the experimental groups involved. 
  • Schedules of outside users will be accommodated to the extent possible when experiment dates are requested.