IPAC2021 - List of Authors (Forck, P.)

Paper	Title	Page
MOPAB279	Non-Invasive Beam Profile Monitoring for the HL-LHC Hollow Electron Lens	884
	A. Salehilashkajani, N. Kumar, O. Sedláček, C.P. Welsch, H.D. Zhang The University of Liverpool, Liverpool, United Kingdom M. Ady, N.S. Chritin, N. Jens, O.R. Jones, R. Kersevan, T. Lefèvre, S. Mazzoni, G. Papazoglou, A. Rossi, G. Schneider, R. Veness CERN, Meyrin, Switzerland P. Forck, S. Udrea GSI, Darmstadt, Germany N. Kumar, O. Sedláček, C.P. Welsch, H.D. Zhang Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Funding: This work was supported by the HL-LHC-UK phase II project funded by STFC under Grant Ref: ST/T001925/1 and the STFC Cockcroft core grant No. ST/G008248/1. A Hollow Electron Lens (HEL) is currently under development for the High-Luminosity upgrade of the Large Hadron Collider (HL-LHC). In this device, a hollow electron beam co-propagates with a central proton beam and provides active halo control in the LHC. To ensure the concentricity of the two beams, a non-invasive diagnostic instrument is currently being commissioned. This instrument is a compact version of an existing prototype that leverages beam induced fluorescence with supersonic gas curtain technology. This contribution includes the design features of this version of the monitor, recent progress, and future plans for tests at the Cockcroft Institute and the electron lens test stand at CERN.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB279
About •	paper received ※ 18 May 2021 paper accepted ※ 15 June 2021 issue date ※ 02 September 2021
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MOPAB283	Simulations of Space-Charge and Guiding Fields Effects on the Performance of Gas Jet Profile Monitoring	898
	O. Sedláček, N. Kumar, A. Salehilashkajani, C.P. Welsch, H.D. Zhang The University of Liverpool, Liverpool, United Kingdom P. Forck, S. Udrea GSI, Darmstadt, Germany N. Kumar, A. Salehilashkajani, O. Sedláček, C.P. Welsch, H.D. Zhang Cockcroft Institute, Warrington, Cheshire, United Kingdom S. Mazzoni, O. Sedláček CERN, Geneva, Switzerland
	Gas jet based profile monitors inject a usually curtain shaped gas jet across a charged particle beam and exploit the results of the minimally invasive beam-gas interaction to provide information about the beam’s transversal profile. Such monitor will be installed as part of the High Luminosity LHC upgrade at CERN in the Hollow Electron Lens (HEL). The HEL represents a new collimation stage increasing the diffusion rate of halo particles by placing a high intensity hollow electron beam concentrically around the LHC beam. The gas jet monitor will use the fluorescence radiation resulting due to the beam-gas interaction to create an image of the profiles of both hollow electron and LHC beams However, the high beam space-charge and strong guiding magnetic field of the electron beam cause significant displacements of the excited molecules, as they are also ionized, and thus image distortions. This work presents preliminary simulation results showing expected fluorescence images of the hollow electron profile as affected by space-charge and guiding fields using simulation tools such as IPMsim. The influence of the estimated electron beam and gas jet curtain parameters are investigated.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB283
About •	paper received ※ 18 May 2021 paper accepted ※ 28 July 2021 issue date ※ 19 August 2021
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MOPAB315	Beam Diagnostics for Commissioning and Operation of the FAIR Proton Linac	972
	T. Sieber, P. Forck, S. Udrea GSI, Darmstadt, Germany J. Herranz, A. Vizcaino-de-Julian Proactive Research and Development, Sabadell, Spain
	For the planned antiproton experiments at FAIR a dedicated proton injector Linac is currently under construction. It will be connected via the old UNILAC transfer beamline to SIS18 and has a length of ~30 m. The Linac will accelerate protons up to a final energy of 68 MeV, at a pulse length of 35 µs and a maximum repetition rate of 4 Hz. It will operate at 325 MHz and consists of a new so called "Ladder" RFQ type, followed by a chain of CH-cavities, partially coupled by rf-coupling cells. We have worked out a diagnostics system, which allows detailed measurement and study of all beam parameters during commissioning and later during regular operation. The diagnostics devices will - in a first step - be installed on a diagnostics testbench for stepwise commissioning. We present the concepts for Linac and testbench with some special emphasis on energy measurements with spectrometer and SEM Grid profile measurements.
	Poster MOPAB315 [3.149 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB315
About •	paper received ※ 14 May 2021 paper accepted ※ 24 June 2021 issue date ※ 30 August 2021
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Paper

Title

Page

Non-Invasive Beam Profile Monitoring for the HL-LHC Hollow Electron Lens

884

A. Salehilashkajani, N. Kumar, O. Sedláček, C.P. Welsch, H.D. Zhang
The University of Liverpool, Liverpool, United Kingdom
M. Ady, N.S. Chritin, N. Jens, O.R. Jones, R. Kersevan, T. Lefèvre, S. Mazzoni, G. Papazoglou, A. Rossi, G. Schneider, R. Veness
CERN, Meyrin, Switzerland
P. Forck, S. Udrea
GSI, Darmstadt, Germany
N. Kumar, O. Sedláček, C.P. Welsch, H.D. Zhang
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Funding: This work was supported by the HL-LHC-UK phase II project funded by STFC under Grant Ref: ST/T001925/1 and the STFC Cockcroft core grant No. ST/G008248/1.
A Hollow Electron Lens (HEL) is currently under development for the High-Luminosity upgrade of the Large Hadron Collider (HL-LHC). In this device, a hollow electron beam co-propagates with a central proton beam and provides active halo control in the LHC. To ensure the concentricity of the two beams, a non-invasive diagnostic instrument is currently being commissioned. This instrument is a compact version of an existing prototype that leverages beam induced fluorescence with supersonic gas curtain technology. This contribution includes the design features of this version of the monitor, recent progress, and future plans for tests at the Cockcroft Institute and the electron lens test stand at CERN.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB279

About •

paper received ※ 18 May 2021 paper accepted ※ 15 June 2021 issue date ※ 02 September 2021

Export •

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

MOPAB283

Simulations of Space-Charge and Guiding Fields Effects on the Performance of Gas Jet Profile Monitoring

898

O. Sedláček, N. Kumar, A. Salehilashkajani, C.P. Welsch, H.D. Zhang
The University of Liverpool, Liverpool, United Kingdom
P. Forck, S. Udrea
GSI, Darmstadt, Germany
N. Kumar, A. Salehilashkajani, O. Sedláček, C.P. Welsch, H.D. Zhang
Cockcroft Institute, Warrington, Cheshire, United Kingdom
S. Mazzoni, O. Sedláček
CERN, Geneva, Switzerland

Gas jet based profile monitors inject a usually curtain shaped gas jet across a charged particle beam and exploit the results of the minimally invasive beam-gas interaction to provide information about the beam’s transversal profile. Such monitor will be installed as part of the High Luminosity LHC upgrade at CERN in the Hollow Electron Lens (HEL). The HEL represents a new collimation stage increasing the diffusion rate of halo particles by placing a high intensity hollow electron beam concentrically around the LHC beam. The gas jet monitor will use the fluorescence radiation resulting due to the beam-gas interaction to create an image of the profiles of both hollow electron and LHC beams However, the high beam space-charge and strong guiding magnetic field of the electron beam cause significant displacements of the excited molecules, as they are also ionized, and thus image distortions. This work presents preliminary simulation results showing expected fluorescence images of the hollow electron profile as affected by space-charge and guiding fields using simulation tools such as IPMsim. The influence of the estimated electron beam and gas jet curtain parameters are investigated.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB283

About •

paper received ※ 18 May 2021 paper accepted ※ 28 July 2021 issue date ※ 19 August 2021

Export •

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

MOPAB315

Beam Diagnostics for Commissioning and Operation of the FAIR Proton Linac

972

T. Sieber, P. Forck, S. Udrea
GSI, Darmstadt, Germany
J. Herranz, A. Vizcaino-de-Julian
Proactive Research and Development, Sabadell, Spain

For the planned antiproton experiments at FAIR a dedicated proton injector Linac is currently under construction. It will be connected via the old UNILAC transfer beamline to SIS18 and has a length of ~30 m. The Linac will accelerate protons up to a final energy of 68 MeV, at a pulse length of 35 µs and a maximum repetition rate of 4 Hz. It will operate at 325 MHz and consists of a new so called "Ladder" RFQ type, followed by a chain of CH-cavities, partially coupled by rf-coupling cells. We have worked out a diagnostics system, which allows detailed measurement and study of all beam parameters during commissioning and later during regular operation. The diagnostics devices will - in a first step - be installed on a diagnostics testbench for stepwise commissioning. We present the concepts for Linac and testbench with some special emphasis on energy measurements with spectrometer and SEM Grid profile measurements.

Poster MOPAB315 [3.149 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB315

About •

paper received ※ 14 May 2021 paper accepted ※ 24 June 2021 issue date ※ 30 August 2021

Export •

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