IBIC2019 - List of Authors (Lefevre, T.)

Paper	Title	Page
TUPP034	Analysis of Quadrupolar Measurements for Beam Size Determination in the LHC	397
	D. Alves, M. Gąsior, T. Lefèvre CERN, Meyrin, Switzerland
	Due to limitations with non-invasive beam size diagnostics in the LHC, particularly during the energy ramp, there has been an interest to explore quadrupolar-based measurements for estimating the transverse beam size, and hence determining the transverse emittance. This technique is especially attractive as it is completely passive and can use the existing beam position instrumentation. In this work, we perform an analysis of this method and present recent measurements taken during energy ramps. Quadrupolar-based measurements are compared with wire-scanner measurements and a calibration strategy is proposed to overcome present limitations.
	Poster TUPP034 [0.897 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP034
About •	paper received ※ 03 September 2019 paper accepted ※ 09 September 2019 issue date ※ 10 November 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEAO04	Beam Measurements at the CERN SPS Using Interferometric Electro-Optic Pickups	457
	A. Arteche, A. Bosco, S.M. Gibson Royal Holloway, University of London, Surrey, United Kingdom S.E. Bashforth, A. Bosco, S.M. Gibson JAI, Egham, Surrey, United Kingdom M. Krupa, T. Lefèvre CERN, Geneva, Switzerland
	Funding: Work supported by UK STFC grants ST/N001583/1, JAI at Royal Holloway University of London and CERN. Since 2016 a prototype electro-optic pickup has been installed on the SPS as part of the ongoing development of a high bandwidth electro-optic beam position monitor for the High Luminosity LHC. Following the success of initial beam signal observations with the prototype, improvements of the sensitivity and stability of the pickup have become the main focus of the project. A new concept has been developed which uses an interferometric technique to measure the image field of a passing bunch. One arm of an interferometer passes through an electro-optic lithium niobate crystal, embedded in a pickup, whereas the other arm bypasses. The recombination after the pickup results in an interference pattern that changes as a bunch passes by, due to the electro-optic response of the crystal to the image field. This technique enhances the sensitivity to the field and improves control of the working point. Results from high intensity beams at the SPS are presented. These include a comparison between two different interferometric configurations that were tested on different pickups with similar beam conditions. The stability is assessed by frequency scanning interferometry during beam operation.
	Slides WEAO04 [52.252 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEAO04
About •	paper received ※ 10 September 2019 paper accepted ※ 12 September 2019 issue date ※ 10 November 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPP037	First Measurements of Cherenkov-Diffraction Radiation at Diamond Light Source	624
	D.M. Harryman, P. Karataev JAI, Egham, Surrey, United Kingdom M. Apollonio, L. Bobb DLS, Oxfordshire, United Kingdom M. Bergamaschi, R. Kieffer, M. Krupa, T. Lefèvre, S. Mazzoni CERN, Geneva, Switzerland A. Potylitsyn TPU, Tomsk, Russia
	Cherenkov Diffraction Radiation (ChDR), appearing when a charged particle moves in the vicinity of a dielectric medium with speed faster than the speed of light inside the medium, is a phenomenon that can be exploited for a range of non-invasive beam diagnostics. By using dielectric radiators that emit photons when in proximity to charged particle beams, one can design devices to measure beam properties such as position, direction and size. The Booster To Storage-ring (BTS) test stand at Diamond Light Source provides a 3 GeV electron beam for diagnostics research. A new vessel string has been installed to allow the BTS test stand to be used to study ChDR diagnostics applicable for both hadron and electron accelerators. This paper will discuss the commissioning of the BTS test stand, as well as exploring the initial results obtained from the ChDR monitor.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEPP037
About •	paper received ※ 04 September 2019 paper accepted ※ 09 September 2019 issue date ※ 10 November 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THAO01	Cherenkov Diffraction Radiation as a tool for beam diagnostics	660
	T. Lefèvre, D. Alves, M. Bergamaschi, A. Curcio, O.R. Jones, R. Kieffer, S. Mazzoni, N. Mounet, A. Schlogelhofer, E. Senes CERN, Geneva, Switzerland M. Apollonio, L. Bobb DLS, Oxfordshire, United Kingdom A. Aryshev, N. Terunuma KEK, Ibaraki, Japan M.G. Billing, Y.L. Bordlemay Padilla, J.V. Conway, J.P. Shanks Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA V.V. Bleko, S.Yu. Gogolev, A.S. Konkov, J.S. Markova, A. Potylitsyn, D.A. Shkitov TPU, Tomsk, Russia K.V. Fedorov, D.M. Harryman, P. Karataev, K. Lekomtsev JAI, Egham, Surrey, United Kingdom J. Gardelle CEA, LE BARP cedex, France K. Łasocha Jagiellonian University, Kraków, Poland
	During the last three years, the emission of Cherenkov Diffraction Radiation (ChDR), appearing when a relativistic charged particle moves in the vicinity of a dielectric medium, has been investigated with the aim of providing non-invasive beam diagnostics. ChDR has very interesting properties, with a large number of photons emitted in a narrow and well-defined solid angle, providing excellent conditions for detection with very little background. This contribution will present a collection of recent beam measurements performed at several facilities such as the Cornell Electron Storage Ring, the Advanced Test Facility 2 at KEK, the Diamond light source in the UK and the CLEAR test facility at CERN. Those results, complemented with simulations, suggest that the use of both incoherent and coherent emission of Cherenkov diffraction radiation could open up new beam instrumentation possibilities for relativistic charged particle beams.
	Slides THAO01 [10.658 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-THAO01
About •	paper received ※ 09 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Analysis of Quadrupolar Measurements for Beam Size Determination in the LHC

397

D. Alves, M. Gąsior, T. Lefèvre
CERN, Meyrin, Switzerland

Due to limitations with non-invasive beam size diagnostics in the LHC, particularly during the energy ramp, there has been an interest to explore quadrupolar-based measurements for estimating the transverse beam size, and hence determining the transverse emittance. This technique is especially attractive as it is completely passive and can use the existing beam position instrumentation. In this work, we perform an analysis of this method and present recent measurements taken during energy ramps. Quadrupolar-based measurements are compared with wire-scanner measurements and a calibration strategy is proposed to overcome present limitations.

Poster TUPP034 [0.897 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP034

About •

paper received ※ 03 September 2019 paper accepted ※ 09 September 2019 issue date ※ 10 November 2019

Export •

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

WEAO04

Beam Measurements at the CERN SPS Using Interferometric Electro-Optic Pickups

457

A. Arteche, A. Bosco, S.M. Gibson
Royal Holloway, University of London, Surrey, United Kingdom
S.E. Bashforth, A. Bosco, S.M. Gibson
JAI, Egham, Surrey, United Kingdom
M. Krupa, T. Lefèvre
CERN, Geneva, Switzerland

Funding: Work supported by UK STFC grants ST/N001583/1, JAI at Royal Holloway University of London and CERN.
Since 2016 a prototype electro-optic pickup has been installed on the SPS as part of the ongoing development of a high bandwidth electro-optic beam position monitor for the High Luminosity LHC. Following the success of initial beam signal observations with the prototype, improvements of the sensitivity and stability of the pickup have become the main focus of the project. A new concept has been developed which uses an interferometric technique to measure the image field of a passing bunch. One arm of an interferometer passes through an electro-optic lithium niobate crystal, embedded in a pickup, whereas the other arm bypasses. The recombination after the pickup results in an interference pattern that changes as a bunch passes by, due to the electro-optic response of the crystal to the image field. This technique enhances the sensitivity to the field and improves control of the working point. Results from high intensity beams at the SPS are presented. These include a comparison between two different interferometric configurations that were tested on different pickups with similar beam conditions. The stability is assessed by frequency scanning interferometry during beam operation.

Slides WEAO04 [52.252 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEAO04

About •

paper received ※ 10 September 2019 paper accepted ※ 12 September 2019 issue date ※ 10 November 2019

Export •

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

WEPP037

First Measurements of Cherenkov-Diffraction Radiation at Diamond Light Source

624

D.M. Harryman, P. Karataev
JAI, Egham, Surrey, United Kingdom
M. Apollonio, L. Bobb
DLS, Oxfordshire, United Kingdom
M. Bergamaschi, R. Kieffer, M. Krupa, T. Lefèvre, S. Mazzoni
CERN, Geneva, Switzerland
A. Potylitsyn
TPU, Tomsk, Russia

Cherenkov Diffraction Radiation (ChDR), appearing when a charged particle moves in the vicinity of a dielectric medium with speed faster than the speed of light inside the medium, is a phenomenon that can be exploited for a range of non-invasive beam diagnostics. By using dielectric radiators that emit photons when in proximity to charged particle beams, one can design devices to measure beam properties such as position, direction and size. The Booster To Storage-ring (BTS) test stand at Diamond Light Source provides a 3 GeV electron beam for diagnostics research. A new vessel string has been installed to allow the BTS test stand to be used to study ChDR diagnostics applicable for both hadron and electron accelerators. This paper will discuss the commissioning of the BTS test stand, as well as exploring the initial results obtained from the ChDR monitor.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-WEPP037

About •

paper received ※ 04 September 2019 paper accepted ※ 09 September 2019 issue date ※ 10 November 2019

Export •

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

THAO01

Cherenkov Diffraction Radiation as a tool for beam diagnostics

660

T. Lefèvre, D. Alves, M. Bergamaschi, A. Curcio, O.R. Jones, R. Kieffer, S. Mazzoni, N. Mounet, A. Schlogelhofer, E. Senes
CERN, Geneva, Switzerland
M. Apollonio, L. Bobb
DLS, Oxfordshire, United Kingdom
A. Aryshev, N. Terunuma
KEK, Ibaraki, Japan
M.G. Billing, Y.L. Bordlemay Padilla, J.V. Conway, J.P. Shanks
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
V.V. Bleko, S.Yu. Gogolev, A.S. Konkov, J.S. Markova, A. Potylitsyn, D.A. Shkitov
TPU, Tomsk, Russia
K.V. Fedorov, D.M. Harryman, P. Karataev, K. Lekomtsev
JAI, Egham, Surrey, United Kingdom
J. Gardelle
CEA, LE BARP cedex, France
K. Łasocha
Jagiellonian University, Kraków, Poland

During the last three years, the emission of Cherenkov Diffraction Radiation (ChDR), appearing when a relativistic charged particle moves in the vicinity of a dielectric medium, has been investigated with the aim of providing non-invasive beam diagnostics. ChDR has very interesting properties, with a large number of photons emitted in a narrow and well-defined solid angle, providing excellent conditions for detection with very little background. This contribution will present a collection of recent beam measurements performed at several facilities such as the Cornell Electron Storage Ring, the Advanced Test Facility 2 at KEK, the Diamond light source in the UK and the CLEAR test facility at CERN. Those results, complemented with simulations, suggest that the use of both incoherent and coherent emission of Cherenkov diffraction radiation could open up new beam instrumentation possibilities for relativistic charged particle beams.

Slides THAO01 [10.658 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-THAO01

About •

paper received ※ 09 September 2019 paper accepted ※ 10 September 2019 issue date ※ 10 November 2019

Export •

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