Jefferson Lab > Physics
Privacy and Security Notice

Accelerator and Experimental Schedule

Experimental Schedule Terms Defined

Commission Commissioning is the period between installation of equipment and systems and their operational use, such as in an experiment. A commissioning period may include initial testing, debugging, reconfiguration, calibration, final testing, operator training, and other activities required to produce fully operational equipment and systems.
 
Date An activity starts at 8 A.M. on the scheduled date and ends at 8 A.M. on the day after the last day it is shown on the schedule.
 
Development Accelerator development (also known as machine development or beam development) is a period set aside for investigating and determining operating characteristics of accelerator equipment and systems. Approved, written test plans are the vehicle for conducting these investigations.
 
Deinstall Deinstall is a period assigned to a hall for the removal of special equipment used for a particular experiment or a set of experiments. Operations may continue in other halls when one hall has a dismount period.
 
Facility Facility Development is a period scheduled by the Nuclear Physics Experiment Scheduling Committee which is used to meet priority needs of the moment, including experiments, commissioning new equipment, and accelerator development.
 
GeV/pass//Pol The energy per pass is specified, such as .8 GeV/pass. Pol asks if the electron beam is polarized or not. Each row in the table will indicate Yes or No as appropriate.
 
GeV/uA The beam energy scheduled for each Hall is indicated in the table, such as 2.3 GeV. The beam current is also indicated in the table, such as 25 uA.
 
Holiday The accelerator and experimental halls are "locked-out" during holiday periods, and no work or operations are scheduled without Head of Operations or Experimental Hall Leader approval.
 
Install Installation is a period assigned to a hall for installing additional or new equipment. Operations may continue in other halls during an install period. If the equipment is to be removed, this will occur typically during a dismount or shutdown period.
 
Maintenance A scheduled accelerator maintenance period normally consists of one shift of tunnel access followed by two shifts of restore. If satisfactory beam is produced in less than two shifts of restore, the available time is normally used for accelerator development. During operating periods, it is normal to have a maintenance day scheduled every other Tuesday.
 
Restore Restore is a period assigned to startup the accelerator and/or to tune the beam to meet specifications for its next scheduled use. Three or more days of restore may be scheduled after a major shutdown or holiday period. Up to two shifts of restore may be scheduled after one shift of maintenance. Short periods of restore may be scheduled after a target or energy change in a hall. Restore may also be referred to as planned or scheduled tuning.
 
Shutdown Normally, a major shutdown is scheduled three times a year, one in January, one after either Memorial Day or Independence Day, and one after Labor Day. A major shutdown applies to the accelerator and all experimental halls, and typically is for at least one week. Extensive preventive and corrective maintenance and possibly installation of new equipment are scheduled for the accelerator and the experimental halls during shutdown. During these periods, beam and RF testing and recertification of the Personnel Safety System (PSS) may be scheduled during periods when they do conflict with scheduled shutdown activities.