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”

04/21/23 2All Experimenters' Meeting

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

progress)04/21/23 3All Experimenters' Meeting

“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!

04/21/23 7All Experimenters' Meeting

04/21/23 8All Experimenters' Meeting

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)

04/21/23 10All Experimenters' Meeting

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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04/21/23 12All Experimenters' Meeting

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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