IPAC2012 - List of Authors (Garion, C.)

Paper	Title	Page
WEPPD016	Development of Glassy Carbon Blade for LHC Fast Vacuum Valve	2528
	C. Garion, P. Coly CERN, Geneva, Switzerland
	An unexpected gas inrush in a vacuum chamber leads to the development of a fast pressure wave. It carries small particles that can compromise the functioning of sensitive machine systems such as the RF cavities or kickers. In the LHC machine, it has been proposed to protect these equipments by the installation of fast vacuum valves. The main requirements for the fast valves and in particular for the blade are: fast closure in the 20 ms range, high transparency and melting temperature in case of closure with beam in, dust free material to not contaminate sensitive adjacent elements and last but not least vacuum compatibility and adequate leak tightness across the blade. In this paper, a design based on a vitreous carbon blade is proposed. The main reasons for this material choice are given. The mechanical study of the blade behaviour under dynamic forces is shown. Fabrication considerations are addressed as well. Tests on prototypes have been carried out on pendulum type fast valves developed for LEP. Results on glassy carbon blades are presented as well as the motion parameter measurements. Qualification of the material for UHV applications has been carried out.

WEPPD017	Development of a New RF Finger Concept for Vacuum Beam Line Interconnections	2531
	C. Garion, A. Lacroix, H. Rambeau CERN, Geneva, Switzerland
	RF contact fingers are primarily used as a transition element to absorb the thermal expansion of vacuum chambers during bake-out and also to compensate for mechanical tolerances. They have to carry the beam image current to avoid the generation of Higher Order Modes and to reduce beam impedances. They are usually made out of copper beryllium thin sheets and are therefore very fragile and critical components. In this paper, a robust design based on a deformable finger concept is proposed. It allows the compensation of large longitudinal movements and also defaults such as transverse offset, twist or bending. The concept of this new RF fingers is first explained, then the design of the component is presented. The mechanical study based on a highly non linear Finite Element model is shown as well as preliminary tests, including fatigue assessment, carried out on prototypes.

WEPPD025	LHC Detector Vacuum System Consolidation for Long Shutdown 1 (LS1) in 2013-2014	2555
	M.A. Gallilee, J. Chaure, P. Cruikshank, J.E. Gallagher, C. Garion, J.M. Jimenez, R. Kersevan, H. Kos, L. Leduc, P. Lepeule, N. Provot, H. Rambeau, R. Veness CERN, Geneva, Switzerland
	The LHC has ventured into unchartered territory for Particle Physics accelerators. A dedicated consolidation program is required between 2013 and 2014 to ensure optimal physics performance. The experiments, ALICE, ATLAS, CMS, and LHCb, will utilise this shutdown, along with the gained experience of three years of physics running, to make optimisations to the detectors. New vacuum technologies have been developed for the experimental areas, to be integrated during this first phase shutdown. These technologies include bellows, vacuum chambers and ion pumps in aluminium, new beryllium vacuum chambers, and composite mechanical supports. An overview of this first phase consolidation program for the LHC experiments is presented.

Paper

Title

Page

Development of Glassy Carbon Blade for LHC Fast Vacuum Valve

2528

C. Garion, P. Coly
CERN, Geneva, Switzerland

An unexpected gas inrush in a vacuum chamber leads to the development of a fast pressure wave. It carries small particles that can compromise the functioning of sensitive machine systems such as the RF cavities or kickers. In the LHC machine, it has been proposed to protect these equipments by the installation of fast vacuum valves. The main requirements for the fast valves and in particular for the blade are: fast closure in the 20 ms range, high transparency and melting temperature in case of closure with beam in, dust free material to not contaminate sensitive adjacent elements and last but not least vacuum compatibility and adequate leak tightness across the blade. In this paper, a design based on a vitreous carbon blade is proposed. The main reasons for this material choice are given. The mechanical study of the blade behaviour under dynamic forces is shown. Fabrication considerations are addressed as well. Tests on prototypes have been carried out on pendulum type fast valves developed for LEP. Results on glassy carbon blades are presented as well as the motion parameter measurements. Qualification of the material for UHV applications has been carried out.

WEPPD017

Development of a New RF Finger Concept for Vacuum Beam Line Interconnections

2531

C. Garion, A. Lacroix, H. Rambeau
CERN, Geneva, Switzerland

RF contact fingers are primarily used as a transition element to absorb the thermal expansion of vacuum chambers during bake-out and also to compensate for mechanical tolerances. They have to carry the beam image current to avoid the generation of Higher Order Modes and to reduce beam impedances. They are usually made out of copper beryllium thin sheets and are therefore very fragile and critical components. In this paper, a robust design based on a deformable finger concept is proposed. It allows the compensation of large longitudinal movements and also defaults such as transverse offset, twist or bending. The concept of this new RF fingers is first explained, then the design of the component is presented. The mechanical study based on a highly non linear Finite Element model is shown as well as preliminary tests, including fatigue assessment, carried out on prototypes.

WEPPD025

LHC Detector Vacuum System Consolidation for Long Shutdown 1 (LS1) in 2013-2014

2555

M.A. Gallilee, J. Chaure, P. Cruikshank, J.E. Gallagher, C. Garion, J.M. Jimenez, R. Kersevan, H. Kos, L. Leduc, P. Lepeule, N. Provot, H. Rambeau, R. Veness
CERN, Geneva, Switzerland

The LHC has ventured into unchartered territory for Particle Physics accelerators. A dedicated consolidation program is required between 2013 and 2014 to ensure optimal physics performance. The experiments, ALICE, ATLAS, CMS, and LHCb, will utilise this shutdown, along with the gained experience of three years of physics running, to make optimisations to the detectors. New vacuum technologies have been developed for the experimental areas, to be integrated during this first phase shutdown. These technologies include bellows, vacuum chambers and ion pumps in aluminium, new beryllium vacuum chambers, and composite mechanical supports. An overview of this first phase consolidation program for the LHC experiments is presented.