IPAC2013 - List of Authors (Wuensch, W.)

Paper	Title	Page
TUPME049	Status of the Exploration of an Alternative CLIC First Energy Stage Based on Klystrons	1676
	D. Schulte, A. Grudiev, P. Lebrun, G. McMonagle, I. Syratchev, W. Wuensch CERN, Geneva, Switzerland
	The Compact Linear Collider is based on a two-beam scheme to accelerate the main, colliding beams. This scheme allows to reach very high centre-of-mass energies. At low collision energies the main beams could be accelerated by powering the accelerating structures with X-band instead of a second beam. We explore this option and indicate the parameters and conceptual design.

TUPME054	Experimental Study of the Effect of Beam Loading on RF Breakdown Rate in CLIC High-gradient Accelerating Structures	1691
	F. Tecker, R. Corsini, M. Dayyani Kelisani, S. Döbert, A. Grudiev, O. Kononenko, S. Lebet, J.L. Navarro Quirante, G. Riddone, I. Syratchev, W. Wuensch CERN, Geneva, Switzerland A. Solodko JINR, Dubna, Moscow Region, Russia
	RF breakdown is a key issue for the multi-TeV high-luminosity e⁺e⁻ Compact Linear Collider (CLIC). Breakdowns in the high-gradient accelerator structures can deflect the beam and decrease the desired luminosity. The limitations of the accelerating structures due to breakdowns have been studied so far without a beam present in the structure. The presence of the beam modifies the distribution of the electrical and magnetic field distributions, which determine the breakdown rate. Therefore an experiment has been designed for high power testing a CLIC prototype accelerating structure with a beam present in the CLIC Test Facility (CTF3). A special beam line allows extracting a beam with nominal CLIC beam current and duration from the CTF3 linac. The paper describes the beam optics design for this experimental beam line and the commissioning of the experiment with beam.

WEPFI018	Comparison of High Gradient Performance in Varying Cavity Geometries	2741
	T. Higo, T. Abe, Y. Arakida, Y. Higashi, S. Matsumoto, T. Shidara, T. Takatomi, M. Yamanaka KEK, Ibaraki, Japan A. Grudiev, G. Riddone, W. Wuensch CERN, Geneva, Switzerland
	Four types of CLIC prototype TW accelerator structures were high-gradient tested at Nextef, KEK, up to 100 MV/m level and the fifth is under test now. The ramping speed of each processing and the resultant breakdown rate were compared among them. From this comparison, it was found that the ramping speed of the structures with opening ports for HOM damping with magnetic coupling became slow and the resultant breakdown rate became high. It was also found that that with lower surface magnetic field showed faster ramping in processing and lower breakdown rate. This indicates the role of the magnetic field on vacuum breakdowns in copper structure at the region of several tens to 100 MV/m. In this paper, we review the processing stage and the high gradient performance of these structures trying to discuss the relevant parameters, surface electric field, surface magnetic field and other parameters such as Sc, “complex pointing vector”, to the performance difference.

THPWA034	Overview of CERN Technology Transfer Strategy and Accelerator-related Activities	3702
	E. Chesta, A. Bertarelli, F. Caspers, P. Chiggiato, S. Sgobba, T. Stora, M. Taborelli, W. Wuensch CERN, Geneva, Switzerland
	CERN, the European Organization for Nuclear Research, is actively engaged in identifying technologies developed for its accelerator complex that could be profitably used by partner research organizations or commercial companies in applications with potentially high socio-economic impact beyond pure fundamental physics research. In the first part of the paper, an overview of CERN current strategy in the field of Technology Transfer and Intellectual Property Management will be presented, with details on the most effective models, implementation tools and processes developed to achieve satisfactory dissemination and valorisation of the knowledge generated within the Organization. In the second part, CERN currently available technology portfolio will be described with focus on cases originated from the Accelerator and Technology Sector. A selection of promising on-going projects embracing a variety of technology fields and application areas will be detailed to showcase technical challenges and possible benefits of initiatives driven by (but not limited to) the needs of CERN scientific programme.

Paper

Title

Page

Status of the Exploration of an Alternative CLIC First Energy Stage Based on Klystrons

1676

D. Schulte, A. Grudiev, P. Lebrun, G. McMonagle, I. Syratchev, W. Wuensch
CERN, Geneva, Switzerland

The Compact Linear Collider is based on a two-beam scheme to accelerate the main, colliding beams. This scheme allows to reach very high centre-of-mass energies. At low collision energies the main beams could be accelerated by powering the accelerating structures with X-band instead of a second beam. We explore this option and indicate the parameters and conceptual design.

TUPME054

Experimental Study of the Effect of Beam Loading on RF Breakdown Rate in CLIC High-gradient Accelerating Structures

1691

F. Tecker, R. Corsini, M. Dayyani Kelisani, S. Döbert, A. Grudiev, O. Kononenko, S. Lebet, J.L. Navarro Quirante, G. Riddone, I. Syratchev, W. Wuensch
CERN, Geneva, Switzerland
A. Solodko
JINR, Dubna, Moscow Region, Russia

RF breakdown is a key issue for the multi-TeV high-luminosity e⁺e⁻ Compact Linear Collider (CLIC). Breakdowns in the high-gradient accelerator structures can deflect the beam and decrease the desired luminosity. The limitations of the accelerating structures due to breakdowns have been studied so far without a beam present in the structure. The presence of the beam modifies the distribution of the electrical and magnetic field distributions, which determine the breakdown rate. Therefore an experiment has been designed for high power testing a CLIC prototype accelerating structure with a beam present in the CLIC Test Facility (CTF3). A special beam line allows extracting a beam with nominal CLIC beam current and duration from the CTF3 linac. The paper describes the beam optics design for this experimental beam line and the commissioning of the experiment with beam.

WEPFI018

Comparison of High Gradient Performance in Varying Cavity Geometries

2741

T. Higo, T. Abe, Y. Arakida, Y. Higashi, S. Matsumoto, T. Shidara, T. Takatomi, M. Yamanaka
KEK, Ibaraki, Japan
A. Grudiev, G. Riddone, W. Wuensch
CERN, Geneva, Switzerland

Four types of CLIC prototype TW accelerator structures were high-gradient tested at Nextef, KEK, up to 100 MV/m level and the fifth is under test now. The ramping speed of each processing and the resultant breakdown rate were compared among them. From this comparison, it was found that the ramping speed of the structures with opening ports for HOM damping with magnetic coupling became slow and the resultant breakdown rate became high. It was also found that that with lower surface magnetic field showed faster ramping in processing and lower breakdown rate. This indicates the role of the magnetic field on vacuum breakdowns in copper structure at the region of several tens to 100 MV/m. In this paper, we review the processing stage and the high gradient performance of these structures trying to discuss the relevant parameters, surface electric field, surface magnetic field and other parameters such as Sc, “complex pointing vector”, to the performance difference.

THPWA034

Overview of CERN Technology Transfer Strategy and Accelerator-related Activities

3702

E. Chesta, A. Bertarelli, F. Caspers, P. Chiggiato, S. Sgobba, T. Stora, M. Taborelli, W. Wuensch
CERN, Geneva, Switzerland

CERN, the European Organization for Nuclear Research, is actively engaged in identifying technologies developed for its accelerator complex that could be profitably used by partner research organizations or commercial companies in applications with potentially high socio-economic impact beyond pure fundamental physics research. In the first part of the paper, an overview of CERN current strategy in the field of Technology Transfer and Intellectual Property Management will be presented, with details on the most effective models, implementation tools and processes developed to achieve satisfactory dissemination and valorisation of the knowledge generated within the Organization. In the second part, CERN currently available technology portfolio will be described with focus on cases originated from the Accelerator and Technology Sector. A selection of promising on-going projects embracing a variety of technology fields and application areas will be detailed to showcase technical challenges and possible benefits of initiatives driven by (but not limited to) the needs of CERN scientific programme.