IBIC2015 - List of Authors (Lefevre, T.)

Paper	Title	Page
TUPB057	Development of a Versatile OTR-ODR Station for Future Linear Colliders	461
	R. Kieffer, M. Bergamaschi, T. Lefèvre, S. Mazzoni CERN, Geneva, Switzerland T. Aumeyr, P. Karataev Royal Holloway, University of London, Surrey, United Kingdom M.G. Billing, J.V. Conway, J.P. Shanks Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA L.M. Bobb DLS, Oxfordshire, United Kingdom N. Terunuma KEK, Ibaraki, Japan
	In order to study the feasibility of Optical Transition (OTR) and Diffraction (ODR) Radiation based profile measurement for the future electron-positron linear colliders (ILC, CLIC) a new dedicated instrument is under development at CERN to be installed in KEK-ATF2 beam line in fall 2015. To optimize sensitivity to micron and sub-micron beam sizes, we plan to observe ODR/OTR in the visible-UV wavelength range, down to approximately 150 nm. ODR light will be produced by narrow (25-500 μm) slits with non-uniform reflectivity. To improve our knowledge on the complex pattern produced by ODR, a preparatory experiment is being conducted on the CTF3 CALIFES beam line (CERN). This device produces interferences between two OTR screens in the visible optical range with the possibility to control the distance between them, i.e. to probe the shadowing region. The new results of this OTR interference measurement will be presented, together with the latest results from the ODR run in CesrTA (Wilson lab-Cornell).
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TUPB060	Development and Test of High Resolution Cavity BPMs for the CLIC Main Beam Linac	474
	J.R. Towler, T. Lefèvre, M. Wendt CERN, Geneva, Switzerland S.T. Boogert, A. Lyapin JAI, Egham, Surrey, United Kingdom B.J. Fellenz Fermilab, Batavia, Illinois, USA
	The main beam of the Compact LInear Collider (CLIC) requires the beam trajectory to be measured with 50 nm spatial resolution. It also requires a time resolution capable of making position measurements of the head and tail of the 156 ns long CLIC bunch train, for use in dispersion free steering based on an energy chirp applied along the train. For this purpose, a stainless steel 15 GHz cavity BPM prototype has been manufactured, installed at the CLIC Test Facility (CTF3) and tested with beam. An improved design has been fabricated from copper. We discuss results from the two types of the prototype pickups, both from laboratory tests and from beam tests. We also cover the development of the new downconverter electronics.
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WEDLA02	High Frequency Electro-Optic Beam Position Monitors for Intra-Bunch Diagnostics at the LHC	606
TUPB072	use link to see paper's listing under its alternate paper code
	S.M. Gibson, A. Arteche, G.E. Boorman, A. Bosco Royal Holloway, University of London, Surrey, United Kingdom P.Y. Darmedru, T. Lefèvre, T.E. Levens CERN, Geneva, Switzerland
	At the HL-LHC, proton bunches will be rotated by crab-cavities close to the interaction regions to maximize the luminosity. A method to rapidly monitor the transverse position of particles within each 1ns bunch is required. A novel, compact beam diagnostic to measure the bunch rotation is under development, based on electro-optic crystals, which have sufficient time resolution (<50ps) to monitor intra-bunch perturbations. The electro-optic beam position monitor uses two pairs of crystals, mounted on opposite sides of the beam pipe, whose birefringence is modified by the electric field of passing charged particle beam. The change of birefringence depends on the electric field which itself depends on the beam position, and is measured using polarized laser beams. The electro-optic response of the crystal to the passing bunch has been simulated for HL-LHC bunch scenarios. An electro-optical test stand including a high voltage modulator has been developed to characterize LiTaO3 and LiNiO3 crystals. Tests to validate the different optical configurations will be reviewed. The opto-mechanical design of an electro-optic prototype that will be installed in the CERN SPS will be presented.
	Slides WEDLA02 [46.475 MB]
	Poster WEDLA02 [10.813 MB]
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Paper

Title

Page

Development of a Versatile OTR-ODR Station for Future Linear Colliders

461

R. Kieffer, M. Bergamaschi, T. Lefèvre, S. Mazzoni
CERN, Geneva, Switzerland
T. Aumeyr, P. Karataev
Royal Holloway, University of London, Surrey, United Kingdom
M.G. Billing, J.V. Conway, J.P. Shanks
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
L.M. Bobb
DLS, Oxfordshire, United Kingdom
N. Terunuma
KEK, Ibaraki, Japan

In order to study the feasibility of Optical Transition (OTR) and Diffraction (ODR) Radiation based profile measurement for the future electron-positron linear colliders (ILC, CLIC) a new dedicated instrument is under development at CERN to be installed in KEK-ATF2 beam line in fall 2015. To optimize sensitivity to micron and sub-micron beam sizes, we plan to observe ODR/OTR in the visible-UV wavelength range, down to approximately 150 nm. ODR light will be produced by narrow (25-500 μm) slits with non-uniform reflectivity. To improve our knowledge on the complex pattern produced by ODR, a preparatory experiment is being conducted on the CTF3 CALIFES beam line (CERN). This device produces interferences between two OTR screens in the visible optical range with the possibility to control the distance between them, i.e. to probe the shadowing region. The new results of this OTR interference measurement will be presented, together with the latest results from the ODR run in CesrTA (Wilson lab-Cornell).

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TUPB060

Development and Test of High Resolution Cavity BPMs for the CLIC Main Beam Linac

474

J.R. Towler, T. Lefèvre, M. Wendt
CERN, Geneva, Switzerland
S.T. Boogert, A. Lyapin
JAI, Egham, Surrey, United Kingdom
B.J. Fellenz
Fermilab, Batavia, Illinois, USA

The main beam of the Compact LInear Collider (CLIC) requires the beam trajectory to be measured with 50 nm spatial resolution. It also requires a time resolution capable of making position measurements of the head and tail of the 156 ns long CLIC bunch train, for use in dispersion free steering based on an energy chirp applied along the train. For this purpose, a stainless steel 15 GHz cavity BPM prototype has been manufactured, installed at the CLIC Test Facility (CTF3) and tested with beam. An improved design has been fabricated from copper. We discuss results from the two types of the prototype pickups, both from laboratory tests and from beam tests. We also cover the development of the new downconverter electronics.

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WEDLA02

High Frequency Electro-Optic Beam Position Monitors for Intra-Bunch Diagnostics at the LHC

606

TUPB072

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

S.M. Gibson, A. Arteche, G.E. Boorman, A. Bosco
Royal Holloway, University of London, Surrey, United Kingdom
P.Y. Darmedru, T. Lefèvre, T.E. Levens
CERN, Geneva, Switzerland

At the HL-LHC, proton bunches will be rotated by crab-cavities close to the interaction regions to maximize the luminosity. A method to rapidly monitor the transverse position of particles within each 1ns bunch is required. A novel, compact beam diagnostic to measure the bunch rotation is under development, based on electro-optic crystals, which have sufficient time resolution (<50ps) to monitor intra-bunch perturbations. The electro-optic beam position monitor uses two pairs of crystals, mounted on opposite sides of the beam pipe, whose birefringence is modified by the electric field of passing charged particle beam. The change of birefringence depends on the electric field which itself depends on the beam position, and is measured using polarized laser beams. The electro-optic response of the crystal to the passing bunch has been simulated for HL-LHC bunch scenarios. An electro-optical test stand including a high voltage modulator has been developed to characterize LiTaO3 and LiNiO3 crystals. Tests to validate the different optical configurations will be reviewed. The opto-mechanical design of an electro-optic prototype that will be installed in the CERN SPS will be presented.

Slides WEDLA02 [46.475 MB]

Poster WEDLA02 [10.813 MB]

Export •

reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text, ※ RIS/RefMan, ※ EndNote (xml)