ICALEPCS2013 - List of Authors (Follin, F.)

Paper

Title

Page

Online Luminosity Optimization at the LHC

1351

F. Follin, R. Alemany-Fernandez, R. Jacobsson
CERN, Geneva, Switzerland

The online luminosity control of the LHC experiments consists of an automatic slow real-time feedback system controlled by a specific experiment software that communicates directly with an LHC application. The LHC application drives a set of corrector magnets to adjust the transversal beam overlap at the interaction point in order to keep the instantaneous luminosity aligned to the target luminosity provided by the experiment. This solution was proposed by the LHCb experiment and tested first in July 2010. It has been in routine operation during the first two years of physics luminosity data taking, 2011 and 2012, in LHCb. It was also adopted for the ALICE experiment during 2011. The experience provides an important basis for the potential future need of levelling the luminosity in all the LHC experiments. This paper describes the implementation of the LHC application controlling the luminosity at the experiments and the information exchanged that allows this automatic control.

Poster THPPC123 [1.344 MB]

THCOCB05

The LHCb Online Luminosity Monitoring and Control

1438

R. Jacobsson, R. Alemany-Fernandez, F. Follin
CERN, Geneva, Switzerland

The LHCb experiment searches for New Physics by precision measurements in heavy flavour physics. The optimization of the data taking conditions relies on accurate monitoring of the instantaneous luminosity, and many physics measurements rely on accurate knowledge of the integrated luminosity. Most of the measurements have potential systematic effects associated with pileup and changing running conditions. To cope with these while aiming at maximising the collected luminosity, a control of the LHCb luminosity was put in operation. It consists of an automatic real-time feedback system controlled from the LHCb online system which communicates directly with an LHC application which in turn adjusts the beam overlap at the interaction point. It was proposed and tested in July 2010 and has been in routine operation during 2011-2012. As a result, LHCb has been operating at well over four times the design pileup, and 95% of the integrated luminosity has been recorded within 3% of the desired luminosity. This paper motivates and describes the implementation and the experience with the online luminosity monitoring and control, including the mechanisms to perform the luminosity calibrations.

Slides THCOCB05 [1.368 MB]

Paper	Title	Page
THPPC123	Online Luminosity Optimization at the LHC	1351
	F. Follin, R. Alemany-Fernandez, R. Jacobsson CERN, Geneva, Switzerland
	The online luminosity control of the LHC experiments consists of an automatic slow real-time feedback system controlled by a specific experiment software that communicates directly with an LHC application. The LHC application drives a set of corrector magnets to adjust the transversal beam overlap at the interaction point in order to keep the instantaneous luminosity aligned to the target luminosity provided by the experiment. This solution was proposed by the LHCb experiment and tested first in July 2010. It has been in routine operation during the first two years of physics luminosity data taking, 2011 and 2012, in LHCb. It was also adopted for the ALICE experiment during 2011. The experience provides an important basis for the potential future need of levelling the luminosity in all the LHC experiments. This paper describes the implementation of the LHC application controlling the luminosity at the experiments and the information exchanged that allows this automatic control.
	Poster THPPC123 [1.344 MB]

THCOCB05	The LHCb Online Luminosity Monitoring and Control	1438
	R. Jacobsson, R. Alemany-Fernandez, F. Follin CERN, Geneva, Switzerland
	The LHCb experiment searches for New Physics by precision measurements in heavy flavour physics. The optimization of the data taking conditions relies on accurate monitoring of the instantaneous luminosity, and many physics measurements rely on accurate knowledge of the integrated luminosity. Most of the measurements have potential systematic effects associated with pileup and changing running conditions. To cope with these while aiming at maximising the collected luminosity, a control of the LHCb luminosity was put in operation. It consists of an automatic real-time feedback system controlled from the LHCb online system which communicates directly with an LHC application which in turn adjusts the beam overlap at the interaction point. It was proposed and tested in July 2010 and has been in routine operation during 2011-2012. As a result, LHCb has been operating at well over four times the design pileup, and 95% of the integrated luminosity has been recorded within 3% of the desired luminosity. This paper motivates and describes the implementation and the experience with the online luminosity monitoring and control, including the mechanisms to perform the luminosity calibrations.
	Slides THCOCB05 [1.368 MB]