IPAC2012 - List of Authors (Kovermann, J.W.)

Paper	Title	Page
THPPC060	Commissioning of the First Klystron-based X-band Power Source at CERN	3428
	J.W. Kovermann, N. Catalan-Lasheras, S. Curt, S. Döbert, G. McMonagle, S.F. Rey, G. Riddone, K.M. Schirm, I. Syratchev, L. Timeo CERN, Geneva, Switzerland J.P. Eichner, A.A. Haase, D.W. Sprehn SLAC, Menlo Park, California, USA A. Hamdi, F. Peauger CEA/DSM/IRFU, France
	A new klystron based x-band rf power source working at 11.994GHz has been installed and commissioned at CERN in collaboration with CEA Saclay and SLAC for CLIC accelerating structure tests. The system comprises a solid state high voltage modulator, an XL5 klystron developed by SLAC, a cavity based SLED type pulse compressor, the necessary low level rf system including rf diagnostics and interlocks and the surrounding vacuum, cooling and controls infrastructure. The klystron can produce up to 50MW rf pulses of 1500ns pulse width and 50Hz repetition rate. After pulse compression, up to 100MW of rf power at 250ns pulse with are available in the structure test bunker. This paper describes in more detail this setup and the results of the commissioning which was necessary to arrive at the mentioned performance.

THPPC061	A 12 kV, 1 kHz, Pulse Generator for Breakdown Studies of Samples for CLIC RF Accelerating Structures	3431
	R.H. Soares, M.J. Barnes, S. Calatroni, J.W. Kovermann, W. Wuensch CERN, Geneva, Switzerland
	Compact Linear Collider (CLIC) RF structures must be capable of sustaining high surface electric fields, in excess of 200 MV/m, with a breakdown (BD) rate below 3×10^-7 breakdowns/pulse/m. Achieving such a low rate requires a detailed understanding of all the steps involved in the mechanism of breakdown. One of the fundamental studies is to investigate the statistical characteristics of the BD rate phenomenon at very low values to understand the origin of an observed dependency of the surface electric field raised to the power of 30. To acquire sufficient BD data, in a reasonable period of time, a high repetition rate pulse generator is required for an existing d.c. spark system at CERN. Following BD of the material sample the pulse generator must deliver a current pulse of several 10’s of Amperes for ~2 μs. A high repetition rate pulse generator has been designed, built and tested; this utilizes pulse forming line technology and employs MOSFET switches. This paper describes the design of the pulse generator and presents measurement results.

Paper

Title

Page

Commissioning of the First Klystron-based X-band Power Source at CERN

3428

J.W. Kovermann, N. Catalan-Lasheras, S. Curt, S. Döbert, G. McMonagle, S.F. Rey, G. Riddone, K.M. Schirm, I. Syratchev, L. Timeo
CERN, Geneva, Switzerland
J.P. Eichner, A.A. Haase, D.W. Sprehn
SLAC, Menlo Park, California, USA
A. Hamdi, F. Peauger
CEA/DSM/IRFU, France

A new klystron based x-band rf power source working at 11.994GHz has been installed and commissioned at CERN in collaboration with CEA Saclay and SLAC for CLIC accelerating structure tests. The system comprises a solid state high voltage modulator, an XL5 klystron developed by SLAC, a cavity based SLED type pulse compressor, the necessary low level rf system including rf diagnostics and interlocks and the surrounding vacuum, cooling and controls infrastructure. The klystron can produce up to 50MW rf pulses of 1500ns pulse width and 50Hz repetition rate. After pulse compression, up to 100MW of rf power at 250ns pulse with are available in the structure test bunker. This paper describes in more detail this setup and the results of the commissioning which was necessary to arrive at the mentioned performance.

THPPC061

A 12 kV, 1 kHz, Pulse Generator for Breakdown Studies of Samples for CLIC RF Accelerating Structures

3431

R.H. Soares, M.J. Barnes, S. Calatroni, J.W. Kovermann, W. Wuensch
CERN, Geneva, Switzerland

Compact Linear Collider (CLIC) RF structures must be capable of sustaining high surface electric fields, in excess of 200 MV/m, with a breakdown (BD) rate below 3×10^-7 breakdowns/pulse/m. Achieving such a low rate requires a detailed understanding of all the steps involved in the mechanism of breakdown. One of the fundamental studies is to investigate the statistical characteristics of the BD rate phenomenon at very low values to understand the origin of an observed dependency of the surface electric field raised to the power of 30. To acquire sufficient BD data, in a reasonable period of time, a high repetition rate pulse generator is required for an existing d.c. spark system at CERN. Following BD of the material sample the pulse generator must deliver a current pulse of several 10’s of Amperes for ~2 μs. A high repetition rate pulse generator has been designed, built and tested; this utilizes pulse forming line technology and employs MOSFET switches. This paper describes the design of the pulse generator and presents measurement results.