Eric Prebys
Accelerator Physics Center, Fermilab
04/21/23
CERN staged the most elaborate media event in the history of physics (history of science?) for the first circulating beam in the LHC on September 10, starting at 8:30AM (CEDT)
Fermilab staged a simultaneous event in the LHC@FNAL Remote Operations Center (ROC) 1:30 AM (CDT) -> “Pajama Party”
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Access to LHC eLogBook Via account logged into CERN network
Full CMS event displays Local web-based applications accessing data pools at the
CERN end Selected LHC accelerator processes
Java processes running on a PC inside the CERN’s “technical network”
Diplayed via a pipeline tunneled through the CERN unix cluster to a virtual Windows desktop running on a MAC in the ROC (yikes!) Beam current toroid (not really sensitive enough to see this
much beam) Beam loss monitors (seemed to really bog down the node,
so we stopped running it) BPM display (our primary tool for monitoring beam
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“Official” monitor of progress Hand updated? Available anywhere via web
Progress prior to event (added by me)
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From the LHC eLogBook:
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General procedure Proceed one octant at a time, closing collimators at the
next point. Take several shots to correct beam deviation
Beam 1 direction
Beam 2 direction (separate display)
New territory!
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9:35 – First beam injected 9:58 – beam past CMS to
point 6 dump 10:15 – beam to point 1
(ATLAS) 10:26 – First turn! …and there was much
rejoicing
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Got 3 turns on beam one Most people went home More cryo problems held off beam 2 for a bit 12:29 – First beam 2 injected More cryo problems Some corrector problems at point 6 14:59 – First full turn (2:30 hours)
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Investigating optics model Evidence of trim quad polarity problem
Focusing on beam 2 Captured beam with RF! Matching looks good ~2 hour lifetimes First wire scan (flying wire) data Measured tunes Increase beam intensity to 5e9 (enough to quench
magnets!) Planned to go back to beam 1, but started having
problems with transformer in IP8 Repaired as of 8:30 this morning, but not yet cold No beam until ~Wednesday
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Capture beams in both directions Continue to study beam optics Work to increase lifetimes Accelerate beam to ~1TeV
Configuration limit in tunnel must be changed to go higher Collide beams (450 GeV up to 1 TeV)
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