IBIC2022 - List of Authors (Krupa, M.)

Paper	Title	Page
WEP10	Detection of a DC Electric Field Using Electro-Optical Crystals	403
	A. Cristiano, M. Krupa CERN, Meyrin, Switzerland R. Hill University of Huddersfield, Huddersfield, United Kingdom
	Standard beam position monitors (BPM) are intrinsically insensitive to beams with no temporal structure, so-called DC beams, which many CERN experiments rely on. We therefore propose a novel detection technique in which the usual BPM electrodes are replaced with electro-optic (EO) crystals. When exposed to an electric field, such crystals change their optical properties. This can be exploited to encode the electric field magnitude onto the polarisation state of a laser beam crossing the crystal. An additional EO crystal, placed outside the vacuum chamber, can be used to control the system’s working point and to introduce a sinusoidal modulation, allowing DC measurements to be performed in the frequency domain. This contribution presents the working principle of this measurement technique, its known limitations, and possible solutions to further increase the system’s performance. Analytical results and simulations for a double-crystal optical chain are benchmarked against the experimental data taken on a laboratory test bench.
	Poster WEP10 [0.940 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-IBIC2022-WEP10
About •	Received ※ 07 September 2022 — Revised ※ 10 September 2022 — Accepted ※ 15 September 2022 — Issue date ※ 03 December 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP12	HL-LHC BPM System Development Status	408
	M. Krupa, I. Degl’Innocenti, D. Gudkov, G. Schneider CERN, Meyrin, Switzerland D.R. Bett JAI, Oxford, United Kingdom
	The demanding instrumentation requirements of the future High Luminosity LHC (HL-LHC) require 44 newly designed Beam Position Monitors (BPM) to be installed around the ATLAS and CMS experiments in 2026-2028. Three BPM types are now in pre-series production, with two more variants under design. Close to the collision point, a set of cryogenic directive coupler BPMs equipped with a brand new acquisition system based on nearly-direct digitization will resolve the position of the two counter-rotating LHC beams occupying a common vacuum chamber. Other new button and stripline BPMs will provide not only the transverse beam position, but also timing signals for the experiments, and diagnostics for the new HL-LHC crab cavities. This contribution summarizes the HL-LHC BPM specifications, gives an overview of the new BPM designs, reports on the pre-series BPM production status and plans for series manufacturing, outlines the foreseen acquisition system architecture, and highlights the first beam measurements carried out with the proof-of-concept electronics for the directive stripline BPMs.
DOI •	reference for this paper ※ doi:10.18429/JACoW-IBIC2022-WEP12
About •	Received ※ 09 September 2022 — Revised ※ 10 September 2022 — Accepted ※ 11 September 2022 — Issue date ※ 03 October 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Detection of a DC Electric Field Using Electro-Optical Crystals

403

A. Cristiano, M. Krupa
CERN, Meyrin, Switzerland
R. Hill
University of Huddersfield, Huddersfield, United Kingdom

Standard beam position monitors (BPM) are intrinsically insensitive to beams with no temporal structure, so-called DC beams, which many CERN experiments rely on. We therefore propose a novel detection technique in which the usual BPM electrodes are replaced with electro-optic (EO) crystals. When exposed to an electric field, such crystals change their optical properties. This can be exploited to encode the electric field magnitude onto the polarisation state of a laser beam crossing the crystal. An additional EO crystal, placed outside the vacuum chamber, can be used to control the system’s working point and to introduce a sinusoidal modulation, allowing DC measurements to be performed in the frequency domain. This contribution presents the working principle of this measurement technique, its known limitations, and possible solutions to further increase the system’s performance. Analytical results and simulations for a double-crystal optical chain are benchmarked against the experimental data taken on a laboratory test bench.

Poster WEP10 [0.940 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-IBIC2022-WEP10

About •

Received ※ 07 September 2022 — Revised ※ 10 September 2022 — Accepted ※ 15 September 2022 — Issue date ※ 03 December 2022

Cite •

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

WEP12

HL-LHC BPM System Development Status

408

M. Krupa, I. Degl’Innocenti, D. Gudkov, G. Schneider
CERN, Meyrin, Switzerland
D.R. Bett
JAI, Oxford, United Kingdom

The demanding instrumentation requirements of the future High Luminosity LHC (HL-LHC) require 44 newly designed Beam Position Monitors (BPM) to be installed around the ATLAS and CMS experiments in 2026-2028. Three BPM types are now in pre-series production, with two more variants under design. Close to the collision point, a set of cryogenic directive coupler BPMs equipped with a brand new acquisition system based on nearly-direct digitization will resolve the position of the two counter-rotating LHC beams occupying a common vacuum chamber. Other new button and stripline BPMs will provide not only the transverse beam position, but also timing signals for the experiments, and diagnostics for the new HL-LHC crab cavities. This contribution summarizes the HL-LHC BPM specifications, gives an overview of the new BPM designs, reports on the pre-series BPM production status and plans for series manufacturing, outlines the foreseen acquisition system architecture, and highlights the first beam measurements carried out with the proof-of-concept electronics for the directive stripline BPMs.

DOI •

reference for this paper ※ doi:10.18429/JACoW-IBIC2022-WEP12

About •

Received ※ 09 September 2022 — Revised ※ 10 September 2022 — Accepted ※ 11 September 2022 — Issue date ※ 03 October 2022

Cite •

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