IPAC2014 - List of Authors (Roncarolo, F.)

Paper	Title	Page
THPME048	Status and Plans for Linac4 Installation and Commissioning	3332
	M. Vretenar, A. Akroh, L. Arnaudon, P. Baudrenghien, G. Bellodi, J.C. Broere, O. Brunner, J.F. Comblin, J. Coupard, V.A. Dimov, J.-F. Fuchs, A. Funken, F. Gerigk, E. Granemann Souza, K. Hanke, J. Hansen, I. Kozsar, J.-B. Lallement, L. Lenardon, J. Lettry, A.M. Lombardi, C. Maglioni, Ø. Midttun, B. Mikulec, D. Nisbet, M.M. Paoluzzi, U. Raich, S. Ramberger, F. Roncarolo, C. Rossi, J.L. Sanchez Alvarez, R. Scrivens, J. Tan, C.A. Valerio, J. Vollaire, R. Wegner, S. Weisz, M. Yarmohammadi Satri, F. Zocca CERN, Geneva, Switzerland
	Linac4 is a normal conducting 160 MeV H⁻ linear accelerator presently being installed and progressively commissioned at CERN. It will replace the ageing 50 MeV Linac2 as injector of the PS Booster (PSB), increasing at the same time its brightness by a factor of two thanks to the higher injection energy. This will be the first step of a program to increase the beam intensity in the LHC injectors for the needs of the High-Luminosity LHC project. After a series of beam measurements on a dedicated test stand the 3 MeV Linac4 front-end, including ion source, RFQ and a beam chopping line, has been recommissioned at its final position in the Linac4 tunnel. Commissioning of the following section, the Drift Tube Linac, is starting. Beam commissioning will take place in steps of increasing energy, to reach the final 160 MeV in 2015. An extended beam measurement phase including testing of stripping equipment for the PSB and a year-long test run to assess and improve Linac4 reliability will take place in 2016, prior to the connection of Linac4 to the PSB that will take place during the next long LHC shut-down.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME048
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPME177	A Novel Approach to Synchrotron Radiation Simulation	3687
SUSPSNE077	use link to see paper's listing under its alternate paper code
	G. Trad, E. Bravin, A. Goldblatt, S. Mazzoni, F. Roncarolo CERN, Geneva, Switzerland G. Trad LPSC, Grenoble Cedex, France
	At the Large Hadron Collider (LHC) at CERN, synchrotron radiation (SR) is used to continuously monitor the transverse properties of the beams. Unfortunately the machine and beam parameters are such that the useful radiation emitted inside a separation dipole, chosen as source, is diffraction limited affecting heavily the accuracy of the measurement. In order to deconvolve the diffraction effects from the acquired beam images and in order to design an alternative monitor based on a double slit interferometer an extensive study of the synchrotron light source and of the optical propagation has been made. This study is based on simulations combining together several existing tools: SRW for the source, ZEMAX for the transport and MATLAB for the "glue" and analysis of the results. The resulting tool is very powerful and can be easily adapted to other synchrotron radiation problems. In this paper the simulation package and the way it is used will be described as well as the results obtained for the LHC and SPS cases.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME177
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPME179	Beam Diagnostics Measurements at 3MeV of the LINAC4 H⁻ Beam at CERN	3694
	F. Zocca, J.C. Allica Santamaria, M. Duraffourg, G.J. Focker, D. Gerard, B. Kolad, L. Lenardon, M. Ludwig, U. Raich, F. Roncarolo, M. Sordet, J. Tan, J. Tassan-Viol, C. Vuitton CERN, Geneva, Switzerland A. Feschenko MIPT, Dolgoprudniy, Moscow Region, Russia A. Feschenko RAS/INR, Moscow, Russia
	As part of the CERN LHC injector chain upgrade, LINAC4 will accelerate H⁻ ions to 160 MeV, replacing the old 50 MeV proton linac. The ion source, the Low Energy Beam Transfer (LEBT) line, the 3 MeV Radio Frequency Quadrupole and the Medium Energy Beam Transfer (MEBT) line hosting a chopper, have been first commissioned in a dedicated test stand and are now tested in the LINAC4 tunnel. Diagnostics devices are installed in the LEBT and MEBT line and in a movable diagnostics test bench which is temporarily added to the MEBT exit. The paper gives an overview of all the instruments used, including beam current transformers, beam position monitors, wire scanners and wire grids for transverse profile measurements, a longitudinal bunch shape monitor and a slit-and-grid emittance meter. The movable test bench also includes a spectrometer that allows measuring the beam energy spread in conjunction with a wire grid. The present understanding of the instrumentation performance is discussed and the measurement results that allowed characterizing the 3 MeV beam in the LINAC4 tunnel are summarized.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME179
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPME190	A Fibre Coupled, Low Power Laserwire Emittance Scanner at CERN LINAC4	3725
	S.M. Gibson, G.E. Boorman, A. Bosco, K.O. Kruchinin Royal Holloway, University of London, Surrey, United Kingdom C. Gabor STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom T. Hofmann, F. Roncarolo CERN, Geneva, Switzerland A.P. Letchford STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom J.K. Pozimski, P. Savage Imperial College of Science and Technology, Department of Physics, London, United Kingdom
	The new LINAC4 will accelerate H⁻ ions to 160 MeV and ultimately replace the existing 50 MeV LINAC2 in the injector chain for the LHC upgrade. During commissioning in 2013, a laserwire scanner and diamond strip detector were installed for non-invasive emittance measurements of the 3 MeV H⁻ beam. Synergy with the 3 MeV H⁻ Front End Test Stand at RAL, has stimulated collaborative development of a novel laserwire system. A low peak power (8kW) pulsed laser is fibre-coupled for remote installation and alignment free operation. Motorized focusing optics enable remote control of the thickness and position of the laserwire delivered to the vacuum chamber, in which the laser light neutralises a small fraction of H⁻ ions. Undeflected by a dipole magnet, these H atoms drift downstream, where their spatial profile is recorded by a highly sensitive diamond strip detector with ns-time resolution. We present first tests of the laserwire emittance scanner, including measurements of the photo detachment signal with respect to the background from residual gas interactions. The first laserwire transverse beam profile and emittance measurements are compared with conventional slit-grid diagnostics.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME190
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Status and Plans for Linac4 Installation and Commissioning

3332

M. Vretenar, A. Akroh, L. Arnaudon, P. Baudrenghien, G. Bellodi, J.C. Broere, O. Brunner, J.F. Comblin, J. Coupard, V.A. Dimov, J.-F. Fuchs, A. Funken, F. Gerigk, E. Granemann Souza, K. Hanke, J. Hansen, I. Kozsar, J.-B. Lallement, L. Lenardon, J. Lettry, A.M. Lombardi, C. Maglioni, Ø. Midttun, B. Mikulec, D. Nisbet, M.M. Paoluzzi, U. Raich, S. Ramberger, F. Roncarolo, C. Rossi, J.L. Sanchez Alvarez, R. Scrivens, J. Tan, C.A. Valerio, J. Vollaire, R. Wegner, S. Weisz, M. Yarmohammadi Satri, F. Zocca
CERN, Geneva, Switzerland

Linac4 is a normal conducting 160 MeV H⁻ linear accelerator presently being installed and progressively commissioned at CERN. It will replace the ageing 50 MeV Linac2 as injector of the PS Booster (PSB), increasing at the same time its brightness by a factor of two thanks to the higher injection energy. This will be the first step of a program to increase the beam intensity in the LHC injectors for the needs of the High-Luminosity LHC project. After a series of beam measurements on a dedicated test stand the 3 MeV Linac4 front-end, including ion source, RFQ and a beam chopping line, has been recommissioned at its final position in the Linac4 tunnel. Commissioning of the following section, the Drift Tube Linac, is starting. Beam commissioning will take place in steps of increasing energy, to reach the final 160 MeV in 2015. An extended beam measurement phase including testing of stripping equipment for the PSB and a year-long test run to assess and improve Linac4 reliability will take place in 2016, prior to the connection of Linac4 to the PSB that will take place during the next long LHC shut-down.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME048

Export •

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

THPME177

A Novel Approach to Synchrotron Radiation Simulation

3687

SUSPSNE077

use link to see paper's listing under its alternate paper code

G. Trad, E. Bravin, A. Goldblatt, S. Mazzoni, F. Roncarolo
CERN, Geneva, Switzerland
G. Trad
LPSC, Grenoble Cedex, France

At the Large Hadron Collider (LHC) at CERN, synchrotron radiation (SR) is used to continuously monitor the transverse properties of the beams. Unfortunately the machine and beam parameters are such that the useful radiation emitted inside a separation dipole, chosen as source, is diffraction limited affecting heavily the accuracy of the measurement. In order to deconvolve the diffraction effects from the acquired beam images and in order to design an alternative monitor based on a double slit interferometer an extensive study of the synchrotron light source and of the optical propagation has been made. This study is based on simulations combining together several existing tools: SRW for the source, ZEMAX for the transport and MATLAB for the "glue" and analysis of the results. The resulting tool is very powerful and can be easily adapted to other synchrotron radiation problems. In this paper the simulation package and the way it is used will be described as well as the results obtained for the LHC and SPS cases.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME177

Export •

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

THPME179

Beam Diagnostics Measurements at 3MeV of the LINAC4 H⁻ Beam at CERN

3694

F. Zocca, J.C. Allica Santamaria, M. Duraffourg, G.J. Focker, D. Gerard, B. Kolad, L. Lenardon, M. Ludwig, U. Raich, F. Roncarolo, M. Sordet, J. Tan, J. Tassan-Viol, C. Vuitton
CERN, Geneva, Switzerland
A. Feschenko
MIPT, Dolgoprudniy, Moscow Region, Russia
A. Feschenko
RAS/INR, Moscow, Russia

As part of the CERN LHC injector chain upgrade, LINAC4 will accelerate H⁻ ions to 160 MeV, replacing the old 50 MeV proton linac. The ion source, the Low Energy Beam Transfer (LEBT) line, the 3 MeV Radio Frequency Quadrupole and the Medium Energy Beam Transfer (MEBT) line hosting a chopper, have been first commissioned in a dedicated test stand and are now tested in the LINAC4 tunnel. Diagnostics devices are installed in the LEBT and MEBT line and in a movable diagnostics test bench which is temporarily added to the MEBT exit. The paper gives an overview of all the instruments used, including beam current transformers, beam position monitors, wire scanners and wire grids for transverse profile measurements, a longitudinal bunch shape monitor and a slit-and-grid emittance meter. The movable test bench also includes a spectrometer that allows measuring the beam energy spread in conjunction with a wire grid. The present understanding of the instrumentation performance is discussed and the measurement results that allowed characterizing the 3 MeV beam in the LINAC4 tunnel are summarized.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME179

Export •

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

THPME190

A Fibre Coupled, Low Power Laserwire Emittance Scanner at CERN LINAC4

3725

S.M. Gibson, G.E. Boorman, A. Bosco, K.O. Kruchinin
Royal Holloway, University of London, Surrey, United Kingdom
C. Gabor
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
T. Hofmann, F. Roncarolo
CERN, Geneva, Switzerland
A.P. Letchford
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
J.K. Pozimski, P. Savage
Imperial College of Science and Technology, Department of Physics, London, United Kingdom

The new LINAC4 will accelerate H⁻ ions to 160 MeV and ultimately replace the existing 50 MeV LINAC2 in the injector chain for the LHC upgrade. During commissioning in 2013, a laserwire scanner and diamond strip detector were installed for non-invasive emittance measurements of the 3 MeV H⁻ beam. Synergy with the 3 MeV H⁻ Front End Test Stand at RAL, has stimulated collaborative development of a novel laserwire system. A low peak power (8kW) pulsed laser is fibre-coupled for remote installation and alignment free operation. Motorized focusing optics enable remote control of the thickness and position of the laserwire delivered to the vacuum chamber, in which the laser light neutralises a small fraction of H⁻ ions. Undeflected by a dipole magnet, these H atoms drift downstream, where their spatial profile is recorded by a highly sensitive diamond strip detector with ns-time resolution. We present first tests of the laserwire emittance scanner, including measurements of the photo detachment signal with respect to the background from residual gas interactions. The first laserwire transverse beam profile and emittance measurements are compared with conventional slit-grid diagnostics.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME190

Export •

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