IBIC2022 - List of Authors (Forck, P.)

Paper	Title	Page
TUP17	HL-LHC Beam Gas Fluorescence Studies for Transverse Profile Measurement	261
	O. Sedláček, M. Ady, C. Castro Sequeiro, A.R. Churchman, S. Mazzoni, G. Schneider, K. Sidorowski, R. Veness CERN, Meyrin, Switzerland P. Forck, S. Udrea GSI, Darmstadt, Germany M. Sameed European Organization for Nuclear Research (CERN), Geneva, Switzerland O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang The University of Liverpool, Liverpool, United Kingdom O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang Cockcroft Institute, Warrington, Cheshire, United Kingdom
	In a gas jet monitor, a supersonic gas curtain is injected into the beam pipe and interacts with the charged particle beam. The monitor exploits fluorescence induced by beam-gas interactions, thus providing a minimally invasive transverse profile measurement. Such a monitor is being developed as part of the High Luminosity LHC upgrade at CERN. As a preliminary study, the fluorescence cross section of relevant gases must be measured for protons at 450 GeV and 6.8 TeV (i.e. the LHC injection and flat top energies). In these measurements, neon, or alternatively nitrogen gas, will be injected into the LHC vacuum pipe by a regulated gas valve to create an extended pressure bump. This work presents the optical detection system that was installed in 2022 in the LHC to measure luminescence cross-section and horizontal beam profile. Preliminary measurements of background light and first signals are presented in this paper.
	Poster TUP17 [0.673 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-IBIC2022-TUP17
About •	Received ※ 07 September 2022 — Revised ※ 10 September 2022 — Accepted ※ 14 September 2022 — Issue date ※ 21 November 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP25	Simulation and Measurements of the Fast Faraday Cups at GSI UNILAC	286
	R. Singh, P. Forck, T. Reichert, A. Reiter GSI, Darmstadt, Germany S. Klaproth THM, Friedberg, Germany G.O. Rodrigues IUAC, New Delhi, India
	Funding: This work is supported by the German Federal Ministry of Education and Research (BMBF) under contract no. 05P21RORB2. Joint Project 05P2021 - R&D Accelerator (DIAGNOSE) The longitudinal charge profiles of the high intensity heavy ion beam accelerated at the GSI UNILAC upto 11.4 MeV/u can differ significantly in consecutive macro-pulses. Variations in bunch shape and mean energy were also observed within a single macro-pulse. In order to have an accurate and fast determination of bunch shape and its evolution within a macro-pulse, a study of fast Faraday Cup designs is underway at GSI. In this contribution, we present CST particle in cell (PIC) simulations of radially coupled co-axial Fast Faraday Cup (RCFFC) and conventional axially coupled FFC (ACFFC) design. The simulation results are compared to the measurements performed under comparable beam conditions primarily with RCFFCs. A rather large impact of secondary electron emission is observed in simulations and experiments. The biasing of the FFC central electrode as a mitigation mechanism on the measured profiles is discussed.
DOI •	reference for this paper ※ doi:10.18429/JACoW-IBIC2022-TUP25
About •	Received ※ 15 September 2022 — Revised ※ 17 September 2022 — Accepted ※ 25 October 2022 — Issue date ※ 02 November 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP36	Beam Characterization of Slow Extraction Measurement at GSI-SIS18 for Transverse Emittance Exchange Experiments	318
	J. Yang, P. Boutachkov, P. Forck, T. Milosic, R. Singh, S. Sorge GSI, Darmstadt, Germany
	Funding: This project has received funding from the European Union’s Horizon 2020 Research and Innovation programme under GA No 101004730. The quality of slowly, typically several seconds, extracted beams from the GSI synchrotron SIS18 is characterized with respect to the temporal beam stability, the so-called spillμstructure on the 100 µs scale. A pilot experiment was performed utilizing transverse emittance exchange to reduce the beam size in the extraction plane, and the improvement of spillμstructure was found. Important beam instrumentation comprises an Ionization Profile Monitor for beam profile measurement inside the synchrotron and a plastic scintillator at the external transfer line for ion counting with up to several 10⁶ particles per second and 20 µs time slices. The performant data acquisition systems, including a scaler and a fast Time-to-Digital Converter (TDC), allow for determining the spill quality. The application of the TDC in the measurement and related MAD-X simulations are discussed.
DOI •	reference for this paper ※ doi:10.18429/JACoW-IBIC2022-TUP36
About •	Received ※ 08 September 2022 — Revised ※ 10 September 2022 — Accepted ※ 11 September 2022 — Issue date ※ 11 October 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP17	Electron Emission (SEM) Grids for the FAIR Proton Linac	426
	J. Herranz Proactive Research and Development, Sabadell, Spain I. Bustinduy, Á. Rodríguez Páramo ESS Bilbao, Zamudio, Spain P. Forck, T. Sieber GSI, Darmstadt, Germany A. Navarro Fernandez CERN, Meyrin, Switzerland
	New SEM-Grid has been developed for FAIR Proton Linac, the instrument consists of 2 harps fixed together in an orthogonal way. This SEM-Grid will provide higher resolution and accuracy measurements as each harp consists of 64 tungsten wires 100 micro-meter in diameter and 0.5 mm pitch. Each wire is fixed to a ceramic PCB with an innovative dynamic stretching system, this system assures wire straightness under typical thermal expansion due to beam heat deposition. Electric field distribution has been performed, 3 main parameters have been optimized, wires distribution, quantity of polarization electrodes and distance between electrodes and wires. The design and production of the SEM-Grids have been performed by the company Proactive R&D that has count on the expertise of ESS-Bilbao to define safe operation limits and signal estimation by means of a code developed specifically for this type of calculations. Preliminary validations of the first prototypes shown good values of electric field behaviour signal. After additional beam test validations to be performed on June 2022, final series of the SEM-Grid will be produced and installed on FAIR proton LINAC.
DOI •	reference for this paper ※ doi:10.18429/JACoW-IBIC2022-WEP17
About •	Received ※ 07 September 2022 — Revised ※ 15 September 2022 — Accepted ※ 18 September 2022 — Issue date ※ 22 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

HL-LHC Beam Gas Fluorescence Studies for Transverse Profile Measurement

261

O. Sedláček, M. Ady, C. Castro Sequeiro, A.R. Churchman, S. Mazzoni, G. Schneider, K. Sidorowski, R. Veness
CERN, Meyrin, Switzerland
P. Forck, S. Udrea
GSI, Darmstadt, Germany
M. Sameed
European Organization for Nuclear Research (CERN), Geneva, Switzerland
O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang
The University of Liverpool, Liverpool, United Kingdom
O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang
Cockcroft Institute, Warrington, Cheshire, United Kingdom

In a gas jet monitor, a supersonic gas curtain is injected into the beam pipe and interacts with the charged particle beam. The monitor exploits fluorescence induced by beam-gas interactions, thus providing a minimally invasive transverse profile measurement. Such a monitor is being developed as part of the High Luminosity LHC upgrade at CERN. As a preliminary study, the fluorescence cross section of relevant gases must be measured for protons at 450 GeV and 6.8 TeV (i.e. the LHC injection and flat top energies). In these measurements, neon, or alternatively nitrogen gas, will be injected into the LHC vacuum pipe by a regulated gas valve to create an extended pressure bump. This work presents the optical detection system that was installed in 2022 in the LHC to measure luminescence cross-section and horizontal beam profile. Preliminary measurements of background light and first signals are presented in this paper.

Poster TUP17 [0.673 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-IBIC2022-TUP17

About •

Received ※ 07 September 2022 — Revised ※ 10 September 2022 — Accepted ※ 14 September 2022 — Issue date ※ 21 November 2022

Cite •

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

TUP25

Simulation and Measurements of the Fast Faraday Cups at GSI UNILAC

286

R. Singh, P. Forck, T. Reichert, A. Reiter
GSI, Darmstadt, Germany
S. Klaproth
THM, Friedberg, Germany
G.O. Rodrigues
IUAC, New Delhi, India

Funding: This work is supported by the German Federal Ministry of Education and Research (BMBF) under contract no. 05P21RORB2. Joint Project 05P2021 - R&D Accelerator (DIAGNOSE)
The longitudinal charge profiles of the high intensity heavy ion beam accelerated at the GSI UNILAC upto 11.4 MeV/u can differ significantly in consecutive macro-pulses. Variations in bunch shape and mean energy were also observed within a single macro-pulse. In order to have an accurate and fast determination of bunch shape and its evolution within a macro-pulse, a study of fast Faraday Cup designs is underway at GSI. In this contribution, we present CST particle in cell (PIC) simulations of radially coupled co-axial Fast Faraday Cup (RCFFC) and conventional axially coupled FFC (ACFFC) design. The simulation results are compared to the measurements performed under comparable beam conditions primarily with RCFFCs. A rather large impact of secondary electron emission is observed in simulations and experiments. The biasing of the FFC central electrode as a mitigation mechanism on the measured profiles is discussed.

DOI •

reference for this paper ※ doi:10.18429/JACoW-IBIC2022-TUP25

About •

Received ※ 15 September 2022 — Revised ※ 17 September 2022 — Accepted ※ 25 October 2022 — Issue date ※ 02 November 2022

Cite •

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

TUP36

Beam Characterization of Slow Extraction Measurement at GSI-SIS18 for Transverse Emittance Exchange Experiments

318

J. Yang, P. Boutachkov, P. Forck, T. Milosic, R. Singh, S. Sorge
GSI, Darmstadt, Germany

Funding: This project has received funding from the European Union’s Horizon 2020 Research and Innovation programme under GA No 101004730.
The quality of slowly, typically several seconds, extracted beams from the GSI synchrotron SIS18 is characterized with respect to the temporal beam stability, the so-called spillμstructure on the 100 µs scale. A pilot experiment was performed utilizing transverse emittance exchange to reduce the beam size in the extraction plane, and the improvement of spillμstructure was found. Important beam instrumentation comprises an Ionization Profile Monitor for beam profile measurement inside the synchrotron and a plastic scintillator at the external transfer line for ion counting with up to several 10⁶ particles per second and 20 µs time slices. The performant data acquisition systems, including a scaler and a fast Time-to-Digital Converter (TDC), allow for determining the spill quality. The application of the TDC in the measurement and related MAD-X simulations are discussed.

DOI •

reference for this paper ※ doi:10.18429/JACoW-IBIC2022-TUP36

About •

Received ※ 08 September 2022 — Revised ※ 10 September 2022 — Accepted ※ 11 September 2022 — Issue date ※ 11 October 2022

Cite •

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

WEP17

Electron Emission (SEM) Grids for the FAIR Proton Linac

426

J. Herranz
Proactive Research and Development, Sabadell, Spain
I. Bustinduy, Á. Rodríguez Páramo
ESS Bilbao, Zamudio, Spain
P. Forck, T. Sieber
GSI, Darmstadt, Germany
A. Navarro Fernandez
CERN, Meyrin, Switzerland

New SEM-Grid has been developed for FAIR Proton Linac, the instrument consists of 2 harps fixed together in an orthogonal way. This SEM-Grid will provide higher resolution and accuracy measurements as each harp consists of 64 tungsten wires 100 micro-meter in diameter and 0.5 mm pitch. Each wire is fixed to a ceramic PCB with an innovative dynamic stretching system, this system assures wire straightness under typical thermal expansion due to beam heat deposition. Electric field distribution has been performed, 3 main parameters have been optimized, wires distribution, quantity of polarization electrodes and distance between electrodes and wires. The design and production of the SEM-Grids have been performed by the company Proactive R&D that has count on the expertise of ESS-Bilbao to define safe operation limits and signal estimation by means of a code developed specifically for this type of calculations. Preliminary validations of the first prototypes shown good values of electric field behaviour signal. After additional beam test validations to be performed on June 2022, final series of the SEM-Grid will be produced and installed on FAIR proton LINAC.

DOI •

reference for this paper ※ doi:10.18429/JACoW-IBIC2022-WEP17

About •

Received ※ 07 September 2022 — Revised ※ 15 September 2022 — Accepted ※ 18 September 2022 — Issue date ※ 22 September 2022

Cite •

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