SSRL Experimental Run Schedule

SSRL generally operates November through August, using the shutdown period for upgrades and maintenance projects. SSRL operates at 500mA and employs a frequent fill schedule to maintain the SPEAR3 current approximately constant. Automatic injections will be conducted every 5 minutes. Automatic injections will only occur at the designated 5 minute intervals (i.e., on the hour and every 5 minutes thereafter). If the injector is not functional at the designated fill time, then the fill will be skipped and a PA announcement will be made. The current will be replenished at the next scheduled fill time after the injector is repaired and normal injection intervals will resume. The operator will give an audible announcement prior to first injection if the current has decreased more than 10%. If consecutive missed fills or a step loss result in SPEAR3 current falling below 450 mA, SPEAR3 Operator will give 10-minute warning before resuming top off to give users opportunity to restart or postpone scans. If SPEAR3 current is above 450 mA following consecutive missed fills or a step loss, SPEAR3 Operator will announce top off to resume on next 5-minute top up interval.

Beam time shifts with the "low alpha" operating mode are scheduled periodically. During these low alpha shifts, SSRL will operate with reduced current in the 100 mA range and top off will be less frequent depending on user requirements, anticipated every 20 minutes rather than every 5 minutes. In 2013-2014, "low alpha" mode was scheduled Feb. 7-10, 2014; Apr. 18-21, 2014; June 13-16, 2014. In 2015, "low alpha" modes are planned:

  • 0600 Friday, February 6, 2015 through 0600 Monday, February 9, 2015
  • 0600 Friday, April 17, 2015 through 0600 Monday, April 20, 2015
  • 0600 Friday, June 12, 2015 through 0600 Monday, June 15, 2015


SSRL User Beam Time Schedules for the 2014-2015 Run Year (~November 17, 2014 - August 10, 2015) will be posted in September.

Submit new proposals and beam time requests through the user portal for the 2015 run by the posted deadlines.

See links to the 2013-2014 schedule below:

SSRL SPEAR Operation/Maintenance Schedule

Accelerator Schedule (for staff)

LCLS Experimental Run Schedules

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