8th LHC Operations Evian Workshop

Session

Session 4: LHC Emittance Preservation

13 Dec 2017, 13:15

Hotel Ermitage

Conveners

Session 4: LHC Emittance Preservation

• Belen Maria Salvachua Ferrando (CERN)
• Roderik Bruce (CERN)

Presentation materials

evian_minutes_session_4.pdf

evian_minutes_session_4.tex

jacow.cls

35. Instrumentation performance and limitations (15 + 5')

Georges Trad (CERN)

13/12/2017, 13:15

Abstract:
Measuring the beam transverse emittance is fundamental in every accelerator, in particular for the LHC, where its precise determination and its preservation is essential to maximize the luminosity and thus the performance of the colliding beams. In this contribution, a review of the status of the synchrotron radiation monitors, the beam gas vertex detector and the wirescanners will...

36. Luminosity Measurements and systematics (15' + 5')

Jamie Boyd (CERN)

13/12/2017, 13:35

Abstract:
This talk will briefly outline the main methods to measure the luminosity and to calibrate the luminosity detectors in the LHC experiments. It will discuss the size of the systematic uncertainties on the measured luminosity at the online and offline level. In addition it will include a discussion on any possible imbalance between the luminosities delivered to ATLAS and CMS during the...

37. Emittance observations (20' + 5')

Michi Hostettler (Universitaet Bern (CH))

13/12/2017, 13:55

Abstract:
The emittance of the LHC beams when arriving in collisions is a key parameter for luminosity. Hence, the emittance of the beams from the injector complex needs to be preserved as well as possible throughout the cycle for maximum luminosity. Moreover, due to the V/H crossing scheme in IP1 and 5, non-round emittances yield different luminosities for ATLAS and CMS. Such a difference was...

38. Emittance intensity & Lumi modeling and evolution (20' + 5')

Stefania Papadopoulou (CERN/ University of Crete (GR))

13/12/2017, 14:20

Abstract:
The LHC luminosity model developed to describe and follow the evolution of the machine luminosity is presented and compared to 2017 data. The model is based on the main mechanisms of luminosity degradation, such as intrabeam scattering, synchrotron radiation, elastic scattering and luminosity burn-off. It was initially introduced for the 2016 run. For the 2017 run, the model is...