Experimental Studies of Transverse and Longitudinal Beam Dynamics in Photoinjector

Abstract

The structure of the T A P free energy of SK spin glasses of finite sizes is studied numerically. The extrapolation of the results to the thermodynamic limit indicates that a solution of the T A P equations corresponds to a saddle point on the boundary beyond which the validity condition of the T A P free energy no longer holds.

Picosecond pulse radiolysis: Dynamics of solvated electrons in ionic liquid and geminate ion recombination in liquid alkanes

“…The bunch length and electron charge in the bunch are variable with changing the laser injection phase in the rf gun, as described in Ref. Yang et al, 2005. In the pulse radiolysis, the laser injection phase is fixed to 30-degree. The bunch charge used is 2.5 nC.…”

“…The bunch charge used is 2.5 nC. The electron bunch length is 2 ps in root-mean-square (rms) obtained by measuring Cherenkov radiation emitted from the electron bunch in air at the exit of the accelerator with a femtosecond streak camera (HAMAMATSU, FESCA-200, C6138) (Yang et al, 2005).…”

“…The low emittance beam produced from the photocathode rf gun provides a high brightness beam with small beam spot size on the sample for the pulse radiolysis. The bunch length of the electron beam produced from the laser-driven electron accelerator is variable from sub-picosecond to ten picoseconds by using the rf compression effect with changing the injection phase of the laser light on the photocathode (Yang et al, 2005).…”

Effects of emittance and space-charge in femtosecond bunch compression

“…The accelerating rf phase in the linac is set as 85 for the minimum energy spread of 0.07% in root mean square (rms) and 94 in order to obtain an optimal energy-phase correlation (i.e., the bunch head is accelerated more than the bunch tail) for the bunch compression. The transverse emittance and the rms bunch length at the exit of the linac are 4.8 mm mrad and 2.0 ps for a bunch charge of 1 nC [15,19], respectively. The beam energy is 32 MeV.…”

Dynamic optical modulation of an electron beam on a photocathode RF gun: Toward intensity-modulated radiation therapy (IMRT)

“…Therefore the emittance does not increase as a result of coulomb repulsion in the low-energy state. A photocathode RF gun can generate a low-emittance pulsed electron beam (Yang et al, 2005(Yang et al, , 2006a.…”