Title :
Microwave quadrupole structures for the CERN Linear Collider
Author :
Schnell, W. ; Wilson, I.
Author_Institution :
CERN, Geneva, Switzerland
Abstract :
Considerable transverse focusing power can be obtained from the high-gradient RF accelerating structure of a linear collider by making either the aperture or the main cell geometry asymmetric. Such structures, acting as microwave quadrupoles, can be used to stabilize transverse wakefields by creating a spread in the transverse oscillation frequencies of the particles within a bunch. The focusing properties of both slotted-iris structures with circular cells and circular-aperture structures with asymmetric cells have been analyzed using the MAFIA computer code and the results compared with the theoretically determined limiting value obtained for an infinitely thin slit. A suitable geometry for CLIC (CERN Linear Collider) 30-GHz structures has been established and a design based on the machine-and-braze technique is proposed.<>
Keywords :
beam handling equipment; focusing; linear accelerators; physics computing; CERN Linear Collider; CLIC; MAFIA computer code; asymmetric cells; circular cells; circular-aperture structures; high-gradient RF accelerating structure; infinitely thin slit; limiting value; machine-and-braze technique; main cell geometry; microwave quadrupoles; slotted-iris structures; transverse focusing power; transverse oscillation frequencies; transverse wakefields; Acceleration; Apertures; Current density; Damping; Geometry; Magnetic analysis; Magnetic fields; Plasma measurements; Radio frequency; Shape;
Conference_Titel :
Particle Accelerator Conference, 1991. Accelerator Science and Technology., Conference Record of the 1991 IEEE
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-7803-0135-8
DOI :
10.1109/PAC.1991.165246
