Performance 2015

A re-commissioning year - normal cavaets particularly apply. Estimates based on 2012's Hubner factor and the indicated physics efficiency. Total consistent with the stated target for the year of 10 fb-1.

Phase Days Physics efficiency Integrated luminosity  
Initial low luminosity run 7 20% few pb-1 low number of bunches
50 ns intensity ramp-up 14 from 21 20% 0.1 fb-1 short fills plus issues: QPS, UFOs, MCS
25 ns phase beta*=80 cm 65 30% 4 fb-1 includes ramp-up and bedding in of 25 ns, beta* might be lowered (65 cm say) later in the run depending on stability, aperture etc. Issues with TDI limit number of injected bunches

Assumed parameters

Parameter 50 ns 25 ns phase 1 25 ns phase 2 - supressed following delays -not fully ruled out
Energy [TeV] 6.5 6.5 6.5
β* (1/2/5/8) [m] 0.8 / 10 / 0.8 / 3 0.8 / 10 / 0.8 / 3 0.4 / 10 / 0.4 / 3
Half X-angle (1/2/5/8) [μrad] -145 / 120 / 145 / -250 -145 / 120 / 145 / -250 -155 / 120 / 155 / -150
Number of colliding bunches (1/5) 1368 2376 (not likely given TDI limitations - scale accordingly) 2448
Bunch population 1.2e11 1.2e11 1.1e11
Emittance into Stable Beams [μm] 2.5 3.5 2.5
Bunch length [ns] - 4 sigma 1.25 1.25 1.25
Peak Luminosity 4.8e33 6.3e33 1.2e34
Peak mean pile-up (inelastic xsection 80 mb) 25 21 34

 

  • Number of bunches injected limited BCMS (144)
  • 80 mb inelastic cross section at 6.5 TeV

 

Updated August 2015

 

 

 

ML