IBIC2018 - List of Keywords (luminosity)

Paper	Title	Other Keywords	Page
MOPA13	Fast Luminosity Monitoring for the SuperKEKB Collider (LumiBelle2 Project)	MMI, detector, feedback, monitoring	51
	C.G. Pang, P. Bambade, S. Di Carlo, D. Jehanno, V. Kubytskyi, Y. Peinaud, C. Rimbault LAL, Orsay, France Y. Funakoshi, S. Uehara KEK, Ibaraki, Japan
	LumiBelle2 is a fast luminosity monitoring system prepared for SuperKEKB. It uses sCVD diamond detectors placed in both the electron and positron rings to measure the Bhabha scattering process at vanishing scattering angle. Two types of online luminosity signals are provided, a Train-Integrated-Luminosity at 1 kHz as input to the dithering feedback system used to maintain optimum overlap between the colliding beams in horizontal plane, and Bunch-Integrated-Luminosities at about 1 Hz to check for variations along the bunch trains. Individual beam sizes and offsets can also be determined from collision scanning. This paper will describe the design of LumiBelle2 and report on its performance during the Phase-2 commissioning of SuperKEKB.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA13
About •	paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019
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MOPB06	DAΦNE Luminosity Monitor	detector, simulation, scattering, experiment	81
	A. De Santis, C. Bisegni, O.R. Blanco-García, O. Coiro, A. Michelotti, C. Milardi, A. Stecchi INFN/LNF, Frascati (Roma), Italy
	The DAΦNE collider instantaneous luminosity has been measured identifying Bhabha scattering events at low polar angle (∼10°) around the beam axis by using two small crystal calorimeters shared with the KLOE-2 experiment. Independent DAQ setup based on !CHAOS, a novel Control System architecture, has been designed and realized in order to implement a fast luminosity monitor, also in view of the DAΦNE future physics runs. The realized setup allows for measurement of Bunch-by-Bunch (BBB) luminosity that allows to investigate the beam-beam interaction for the Crab-Waist collisions at DAΦNE and luminosity dependence on the bunch train structure.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB06
About •	paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
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TUPC13	Early Commissioning of the Luminosity Dither Feedback for SuperKEKB	feedback, MMI, controls, electron	328
	M. Masuzawa, Y. Funakoshi, T. Kawamoto, S. Nakamura, T. Oki, M. Tobiyama, S. Uehara KEK, Ibaraki, Japan P. Bambade, S. Di Carlo, D. Jehanno, C.G. Pang LAL, Orsay, France D.G. Brown, A.S. Fisher, M.K. Sullivan SLAC, Menlo Park, California, USA D. El Khechen CERN, Geneva, Switzerland U. Wienands ANL, Argonne, Illinois, USA
	SuperKEKB is an electron-positron collider, which aims to achieve a peak luminosity of 8×10³⁵ cm^-2 s⁻¹ using what is known as the "nano-beam" scheme. This paper reports on the commissioning and performance of a luminosity dither feedback. The system, based on one previously used at SLAC for PEP-II, is employed for collision orbit feedback in the horizontal plane. Twelve air-core Helmholtz coils drive the positron beam sinusoidally at a frequency near 80 Hz, forming a closed bump at the interaction point. A lock-in amplifier detects the amplitude and phase of the corresponding frequency component of the luminosity signal. When the beams are aligned for peak luminosity, the magnitude of the luminosity component at the dithering frequency becomes zero. The magnitude grows as the beams are offset, and the phase shifts by 180 degrees when the direction of the necessary correction reverses. The hardware and algorithm were tested during SuperKEKB Phase II run. The electron beam orbit was successfully adjusted to minimize the amplitude of the dither frequency component of the luminosity signal, and the optimal condition was maintained by continuously adjusting the electron beam orbit.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC13
About •	paper received ※ 09 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019
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WEPB13	Beam-Gas Imaging Measurements at LHCb	detector, experiment, vacuum, injection	459
	G.R. Coombs, M. Ferro-Luzzi, R. Matev CERN, Meyrin, Switzerland
	The LHCb detector is one of the four large particle physics experiments situated around the LHC ring. The excellent spatial resolution of the experiment’s vertex locator (VELO) and tracking system allows the accurate reconstruction of interactions between the LHC beam and either residual or injected gas molecules. These reconstructed beam-gas interactions gives LHCb the ability, unique among experiments, to measure the shape and the longitudinal distribution of the beams. Analysis methods were originally developed for the purpose of absolute luminosity calibration, achieving an unprecedented precision of 1.2% in Run I. They have since been extended and applied for online beam-profile monitoring that is continuously published to the LHC, for dedicated cross-calibration with other LHC beam profile monitors and for studies of the dynamic vacuum effects due to the proximity of the VELO subdetector to the beam. In this talk, we give an overview of the LHCb experience with beam-gas imaging techniques, we present recent results on the outlined topics and we summarise the developments that are being pursued for the ultimate understanding of the Run II measurements.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB13
About •	paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPA13

Fast Luminosity Monitoring for the SuperKEKB Collider (LumiBelle2 Project)

MMI, detector, feedback, monitoring

51

C.G. Pang, P. Bambade, S. Di Carlo, D. Jehanno, V. Kubytskyi, Y. Peinaud, C. Rimbault
LAL, Orsay, France
Y. Funakoshi, S. Uehara
KEK, Ibaraki, Japan

LumiBelle2 is a fast luminosity monitoring system prepared for SuperKEKB. It uses sCVD diamond detectors placed in both the electron and positron rings to measure the Bhabha scattering process at vanishing scattering angle. Two types of online luminosity signals are provided, a Train-Integrated-Luminosity at 1 kHz as input to the dithering feedback system used to maintain optimum overlap between the colliding beams in horizontal plane, and Bunch-Integrated-Luminosities at about 1 Hz to check for variations along the bunch trains. Individual beam sizes and offsets can also be determined from collision scanning. This paper will describe the design of LumiBelle2 and report on its performance during the Phase-2 commissioning of SuperKEKB.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPA13

About •

paper received ※ 04 September 2018 paper accepted ※ 11 September 2018 issue date ※ 29 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPB06

DAΦNE Luminosity Monitor

detector, simulation, scattering, experiment

81

A. De Santis, C. Bisegni, O.R. Blanco-García, O. Coiro, A. Michelotti, C. Milardi, A. Stecchi
INFN/LNF, Frascati (Roma), Italy

The DAΦNE collider instantaneous luminosity has been measured identifying Bhabha scattering events at low polar angle (∼10°) around the beam axis by using two small crystal calorimeters shared with the KLOE-2 experiment. Independent DAQ setup based on !CHAOS, a novel Control System architecture, has been designed and realized in order to implement a fast luminosity monitor, also in view of the DAΦNE future physics runs. The realized setup allows for measurement of Bunch-by-Bunch (BBB) luminosity that allows to investigate the beam-beam interaction for the Crab-Waist collisions at DAΦNE and luminosity dependence on the bunch train structure.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-MOPB06

About •

paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPC13

Early Commissioning of the Luminosity Dither Feedback for SuperKEKB

feedback, MMI, controls, electron

328

M. Masuzawa, Y. Funakoshi, T. Kawamoto, S. Nakamura, T. Oki, M. Tobiyama, S. Uehara
KEK, Ibaraki, Japan
P. Bambade, S. Di Carlo, D. Jehanno, C.G. Pang
LAL, Orsay, France
D.G. Brown, A.S. Fisher, M.K. Sullivan
SLAC, Menlo Park, California, USA
D. El Khechen
CERN, Geneva, Switzerland
U. Wienands
ANL, Argonne, Illinois, USA

SuperKEKB is an electron-positron collider, which aims to achieve a peak luminosity of 8×10³⁵ cm^-2 s⁻¹ using what is known as the "nano-beam" scheme. This paper reports on the commissioning and performance of a luminosity dither feedback. The system, based on one previously used at SLAC for PEP-II, is employed for collision orbit feedback in the horizontal plane. Twelve air-core Helmholtz coils drive the positron beam sinusoidally at a frequency near 80 Hz, forming a closed bump at the interaction point. A lock-in amplifier detects the amplitude and phase of the corresponding frequency component of the luminosity signal. When the beams are aligned for peak luminosity, the magnitude of the luminosity component at the dithering frequency becomes zero. The magnitude grows as the beams are offset, and the phase shifts by 180 degrees when the direction of the necessary correction reverses. The hardware and algorithm were tested during SuperKEKB Phase II run. The electron beam orbit was successfully adjusted to minimize the amplitude of the dither frequency component of the luminosity signal, and the optimal condition was maintained by continuously adjusting the electron beam orbit.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC13

About •

paper received ※ 09 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPB13

Beam-Gas Imaging Measurements at LHCb

detector, experiment, vacuum, injection

459

G.R. Coombs, M. Ferro-Luzzi, R. Matev
CERN, Meyrin, Switzerland

The LHCb detector is one of the four large particle physics experiments situated around the LHC ring. The excellent spatial resolution of the experiment’s vertex locator (VELO) and tracking system allows the accurate reconstruction of interactions between the LHC beam and either residual or injected gas molecules. These reconstructed beam-gas interactions gives LHCb the ability, unique among experiments, to measure the shape and the longitudinal distribution of the beams. Analysis methods were originally developed for the purpose of absolute luminosity calibration, achieving an unprecedented precision of 1.2% in Run I. They have since been extended and applied for online beam-profile monitoring that is continuously published to the LHC, for dedicated cross-calibration with other LHC beam profile monitors and for studies of the dynamic vacuum effects due to the proximity of the VELO subdetector to the beam. In this talk, we give an overview of the LHCb experience with beam-gas imaging techniques, we present recent results on the outlined topics and we summarise the developments that are being pursued for the ultimate understanding of the Run II measurements.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-WEPB13

About •

paper received ※ 05 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)