TY - CPAPER
AU - Mirian, N.S.
AU - Maraghechi, B.
AU - Salehi, E.
TI - Efficiency Enhancement of a Harmonic Lasing Free-Electron Laser
J2 - Proc. of FEL2015
AB - The harmonic lasing free-electron laser amplifier, in which two wigglers is employed in order for the fundamental resonance of the second wiggler to coincide with the third harmonic of the first wiggler to generate ultraviolet radiation, is studied. A set of coupled nonlinear first-order differential equations describing the nonlinear evolution of the system, for a long electron bunch, is solved numerically by CYRUS code. Thermal effects in the form of longitudinal velocity spread are also investigated. The second wiggler field decreases linearly and nonlinearly at the point where the radiation of the third harmonic saturates to enhance the efficiency. The optimum starting point and the slope of the tapering of the amplitude of the wiggler are found by a successive run of the code. It is found that tapering can increase the saturated power of the third harmonic considerably.
PB - JACoW
CY - Geneva, Switzerland
SP - 209
EP - 212
KW - wiggler
KW - electron
KW - radiation
KW - resonance
KW - FEL
DA - 2015/12
PY - 2015
SN - 978-3-95450-134-2
DO - 10.18429/JACoW-FEL2015-MOP074
UR - http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/mop074.pdf
ER -