IPAC2012 - List of Authors (Chritin, N.)

Paper	Title	Page
MOPPR057	Development of a Cavity Beam Position Monitor for CLIC	915
	F.J. Cullinan, S.T. Boogert, N.Y. Joshi, A. Lyapin JAI, Egham, Surrey, United Kingdom E. Calvo, N. Chritin, F. Guillot-Vignot, T. Lefèvre, L. Søby CERN, Geneva, Switzerland A. Lunin, M. Wendt, V.P. Yakovlev Fermilab, Batavia, USA S.R. Smith SLAC, Menlo Park, California, USA
	The Compact Linear Collider (CLIC) project presents many challenges to its subsystems and the beam diagnostics in particular must perform beyond current limitations. The requirements for the CLIC main beam position monitors foresee a spacial resolution of 50 nm while delivering a 10 ns temporal resolution within the bunch train. We discuss the design of the microwave cavity pick-up and associated electronics, bench top tests with the first prototype cavity, as well as some of the machine-specific integration and operational issues.

WEPPD029	The Mechanical Design of a Collimator and Cryogenic Bypass for Installation in the Dispersion Suppressors of the LHC	2567
	D. Ramos, L. Alberty Vieira, A. Bertarelli, A. Cherif, N. Chritin, R. Claret, L. Gentini, D. Lombard, P. Minginette, P. Moyret, M. Redondas Monteserin, T. Renaglia, M.A. Timmins CERN, Geneva, Switzerland
	A project to install collimators in the dispersion suppressor regions of the LHC was launched early 2010, aiming to reduce the power deposition in superconducting magnets by a factor of 10. To be placed in the continuous arc cryostat, the design of such collimators had to comply with challenging integration, functional and time constraints. A pre-study for a cold collimator solution was launched in parallel with an alternative design consisting of a room temperature collimator and a cryogenic bypass. The second was eventually preferred, as it was based on proven LHC technologies for cryogenic, vacuum, electrical and collimator material solutions, despite the increased difficulty on the mechanical integration and assembly. This paper presents the mechanical design of a cryogenic bypass for the LHC continuous cryostat and respective collimator unit, both made to comply with the functionality of existing LHC systems. The approach taken to achieve a reliable design within schedule will be explained alongside the measures adopted to validate new solutions, in particular, when dealing with welding distortions, systems routing, thermal loads and precision mechanics.

WEPPD074	Issues and Feasibility Demonstration of Positioning Closed Loop Control for the CLIC Supporting System Using a Test Mock-up with Five Degrees of Freedom	2696
	M. Sosin, M. Anastasopoulos, N. Chritin, J. Kemppinen, H. Mainaud Durand, V. Rude, G. Sterbini, S. griffet CERN, Geneva, Switzerland
	Since several years, CERN is studying the feasibility of building a high energy e⁺ e⁻ linear collider: the CLIC (Compact LInear Collider). One of the challenges of such a collider is the pre-alignment precision and accuracy requirement on the transverse positions of the linac components, which is typically 14 μm over a window of 200 m. To ensure the possibility of positioning within such tight constraints, CERN Beams Department’s Survey team has worked intensively at developing the methods and technology needed to achieve that objective. This paper describes activities which were performed on a test bench (mock-up) with five degrees of freedom (DOF) for the qualification of control algorithms for the CLIC supporting system active-pre-alignment. Present understanding, lessons learned (“know how”), issues of sensors noise and mechanical components nonlinearities are presented.

THPPP011	Studies on a Wideband, Solid-state Driven RF System for the CERN PS Booster	3749
	M.M. Paoluzzi, L. Arnaudon, N. Chritin, M. Haase, K. Hanke, B. Mikulec, T. Tardy CERN, Geneva, Switzerland
	In the framework of the LHC Injectors Upgrade project (LIU) the PS Booster (PSB) RF systems will undergo in depth consolidation and upgrade programs. The aim is increasing the extraction energy to 2 GeV and allowing reliable operations during next 25 years. Substantial improvements could come from the replacement of the existing narrowband, tuned systems covering the h=1 and h=2 frequency ranges (0.6 / 1.8 MHz and 1.2 / 3.6 MHz respectively) with wideband (0.5 / 4 MHz) Finemet® loaded cavities. The new system would be modular, allow multi-harmonic operation, use solid-state power stages and include fast RF feedback to compensate beam loading effects to some extent. A prove of principle system providing ≈3.0 kV accelerating voltage has been designed, constructed and installed in one of the PSB rings. This paper provides details on the design and measurements as well as information on the project status.

Paper

Title

Page

Development of a Cavity Beam Position Monitor for CLIC

915

F.J. Cullinan, S.T. Boogert, N.Y. Joshi, A. Lyapin
JAI, Egham, Surrey, United Kingdom
E. Calvo, N. Chritin, F. Guillot-Vignot, T. Lefèvre, L. Søby
CERN, Geneva, Switzerland
A. Lunin, M. Wendt, V.P. Yakovlev
Fermilab, Batavia, USA
S.R. Smith
SLAC, Menlo Park, California, USA

The Compact Linear Collider (CLIC) project presents many challenges to its subsystems and the beam diagnostics in particular must perform beyond current limitations. The requirements for the CLIC main beam position monitors foresee a spacial resolution of 50 nm while delivering a 10 ns temporal resolution within the bunch train. We discuss the design of the microwave cavity pick-up and associated electronics, bench top tests with the first prototype cavity, as well as some of the machine-specific integration and operational issues.

WEPPD029

The Mechanical Design of a Collimator and Cryogenic Bypass for Installation in the Dispersion Suppressors of the LHC

2567

D. Ramos, L. Alberty Vieira, A. Bertarelli, A. Cherif, N. Chritin, R. Claret, L. Gentini, D. Lombard, P. Minginette, P. Moyret, M. Redondas Monteserin, T. Renaglia, M.A. Timmins
CERN, Geneva, Switzerland

A project to install collimators in the dispersion suppressor regions of the LHC was launched early 2010, aiming to reduce the power deposition in superconducting magnets by a factor of 10. To be placed in the continuous arc cryostat, the design of such collimators had to comply with challenging integration, functional and time constraints. A pre-study for a cold collimator solution was launched in parallel with an alternative design consisting of a room temperature collimator and a cryogenic bypass. The second was eventually preferred, as it was based on proven LHC technologies for cryogenic, vacuum, electrical and collimator material solutions, despite the increased difficulty on the mechanical integration and assembly. This paper presents the mechanical design of a cryogenic bypass for the LHC continuous cryostat and respective collimator unit, both made to comply with the functionality of existing LHC systems. The approach taken to achieve a reliable design within schedule will be explained alongside the measures adopted to validate new solutions, in particular, when dealing with welding distortions, systems routing, thermal loads and precision mechanics.

WEPPD074

Issues and Feasibility Demonstration of Positioning Closed Loop Control for the CLIC Supporting System Using a Test Mock-up with Five Degrees of Freedom

2696

M. Sosin, M. Anastasopoulos, N. Chritin, J. Kemppinen, H. Mainaud Durand, V. Rude, G. Sterbini, S. griffet
CERN, Geneva, Switzerland

Since several years, CERN is studying the feasibility of building a high energy e⁺ e⁻ linear collider: the CLIC (Compact LInear Collider). One of the challenges of such a collider is the pre-alignment precision and accuracy requirement on the transverse positions of the linac components, which is typically 14 μm over a window of 200 m. To ensure the possibility of positioning within such tight constraints, CERN Beams Department’s Survey team has worked intensively at developing the methods and technology needed to achieve that objective. This paper describes activities which were performed on a test bench (mock-up) with five degrees of freedom (DOF) for the qualification of control algorithms for the CLIC supporting system active-pre-alignment. Present understanding, lessons learned (“know how”), issues of sensors noise and mechanical components nonlinearities are presented.

THPPP011

Studies on a Wideband, Solid-state Driven RF System for the CERN PS Booster

3749

M.M. Paoluzzi, L. Arnaudon, N. Chritin, M. Haase, K. Hanke, B. Mikulec, T. Tardy
CERN, Geneva, Switzerland

In the framework of the LHC Injectors Upgrade project (LIU) the PS Booster (PSB) RF systems will undergo in depth consolidation and upgrade programs. The aim is increasing the extraction energy to 2 GeV and allowing reliable operations during next 25 years. Substantial improvements could come from the replacement of the existing narrowband, tuned systems covering the h=1 and h=2 frequency ranges (0.6 / 1.8 MHz and 1.2 / 3.6 MHz respectively) with wideband (0.5 / 4 MHz) Finemet® loaded cavities. The new system would be modular, allow multi-harmonic operation, use solid-state power stages and include fast RF feedback to compensate beam loading effects to some extent. A prove of principle system providing ≈3.0 kV accelerating voltage has been designed, constructed and installed in one of the PSB rings. This paper provides details on the design and measurements as well as information on the project status.