Title :
Beam dynamics enhancement due to accelerating field symmetrization in the BNL/SLAC/UCLA 1.6 cell S-band photocathode RF gun
Author :
Palmer, D.T. ; Wang, X.J. ; Ben-Zvi, I. ; Miller, R.H.
Author_Institution :
Linear Accel. Center, Stanford Univ., CA, USA
Abstract :
A 1.6 cell photocathode S-Band gun developed by the BNL/SLAC/UCLA collaboration is now in operation at the Brookhaven Accelerator Test Facility (ATF). One of the main features of this RF gun is the symmetrization of the RF coupling iris with a identical vacuum pumping port located in the full cell. The effects of the asymmetry caused by the RF coupling iris were experimentally investigated by positioning a metallic plunger at the back wall of the vacuum port iris. The higher order modes produced were studied using electron beamlets with 8-fold symmetry. The 8-fold beamlets were produced by masking the laser beam. These experimental results indicate that the integrated electrical center and the geometrical center of the gun are within 175 μm,. which is within the laser alignment tolerance of 250 μm
Keywords :
electron guns; electron sources; particle beam dynamics; BNL/SLAC/UCLA 1.6 cell S-band photocathode RF gun; RF coupling iris; accelerating field symmetrization; beam dynamics enhancement; electron beamlets; geometrical center; identical vacuum pumping port; integrated electrical center; metallic plunger; vacuum port iris; Acceleration; Cathodes; Collaboration; Electron beams; Iris; Laser modes; Life estimation; Particle beams; Radio frequency; Test facilities;
Conference_Titel :
Particle Accelerator Conference, 1997. Proceedings of the 1997
Conference_Location :
Vancouver, BC
Print_ISBN :
0-7803-4376-X
DOI :
10.1109/PAC.1997.752838
