FEL2012 - List of Authors (Bakr, M. A.)

Paper	Title	Page
WEPD65	Design and Numerical Simulation of THz-FEL Amplifier in Kyoto University	519
	M. A. Bakr, Y.W. Choi, T. Kii, R. Kinjo, K. Masuda, H. Negm, H. Ohgaki, M. Omer, K. Shimahashi, K. Yoshida, H. Zen Kyoto University, Institute for Advanced Energy, Kyoto, Japan M. A. Bakr Assiut University, Assiut, Egypt
	Design of a compact and economic THz free-electron laser (FEL) amplifier, which consists of a BNL-type 1.6 cells photocathode radio frequency gun, Solenoid, transport line and short undulator, has been studied at Kyoto University. The electron beam energy to obtain FEL with a wavelength of the range 150~400 μm was calculated to be 4.1~7.0 MeV for a bunch charge of 1.0 nC/bunch. The numerical calculations of the electron beam from the RF gun up to the undulator entrance are carried out using Parmela code and the FEL properties from the undulator will be simulated using GENESIS 1.3. The expected FEL spectral was estimated using 4~5 undulator periods with ~30 cm length and 0.3 T magnetic field. Details of the design concept, numerical calculations and results will be presented in the conference.

WEPD38	Improvement of KU-FEL Performance by Replacing Undulator and Optical Cavity	449
	H. Zen, M. A. Bakr, Y.W. Choi, H. Imon, T. Kii, R. Kinjo, T. Konstantin, K. Masuda, H. Negm, H. Ohgaki, K. Okumura, M. Omer, S. Shibata, K. Shimahashi, K. Yoshida Kyoto University, Institute for Advanced Energy, Kyoto, Japan
	A mid-infrared FEL named as KU-FEL (Kyoto University FEL) has been developed for energy related sciences. The FEL achieved first lasing and saturation in 2008,*. However, the tunable range was limited from 10 to 13 micro-m because of insufficient macro-pulse duration of e-beam and FEL gain. The undulator of KU-FEL has been replaced with the undulator which was previously used for ERL-FEL in JAEA. The optical cavity has been replaced with optimized one. In addition the diameter of the coupling hole on the upstream cavity mirror has been reduced from 2 to 1 mm for reducing cavity loss. After installation, the tunable range of KU-FEL has been improved to 5-15 micro-m. Estimated FEL gain is greater than 30%, which was 1.5 times larger than original configuration. H. Zen, et al., Infrared Physics and Technology, Vol. 51, Issue 5, p.382 (2008) H. Ohgaki, et al., Proc. of FEL08, p.4 (2008) *H. Ohgaki, et al., Proc. of FEL09, p.572 (2009)

Paper

Title

Page

Design and Numerical Simulation of THz-FEL Amplifier in Kyoto University

519

M. A. Bakr, Y.W. Choi, T. Kii, R. Kinjo, K. Masuda, H. Negm, H. Ohgaki, M. Omer, K. Shimahashi, K. Yoshida, H. Zen
Kyoto University, Institute for Advanced Energy, Kyoto, Japan
M. A. Bakr
Assiut University, Assiut, Egypt

Design of a compact and economic THz free-electron laser (FEL) amplifier, which consists of a BNL-type 1.6 cells photocathode radio frequency gun, Solenoid, transport line and short undulator, has been studied at Kyoto University. The electron beam energy to obtain FEL with a wavelength of the range 150~400 μm was calculated to be 4.1~7.0 MeV for a bunch charge of 1.0 nC/bunch. The numerical calculations of the electron beam from the RF gun up to the undulator entrance are carried out using Parmela code and the FEL properties from the undulator will be simulated using GENESIS 1.3. The expected FEL spectral was estimated using 4~5 undulator periods with ~30 cm length and 0.3 T magnetic field. Details of the design concept, numerical calculations and results will be presented in the conference.

WEPD38

Improvement of KU-FEL Performance by Replacing Undulator and Optical Cavity

449

H. Zen, M. A. Bakr, Y.W. Choi, H. Imon, T. Kii, R. Kinjo, T. Konstantin, K. Masuda, H. Negm, H. Ohgaki, K. Okumura, M. Omer, S. Shibata, K. Shimahashi, K. Yoshida
Kyoto University, Institute for Advanced Energy, Kyoto, Japan

A mid-infrared FEL named as KU-FEL (Kyoto University FEL) has been developed for energy related sciences*. The FEL achieved first lasing and saturation in 2008**,***. However, the tunable range was limited from 10 to 13 micro-m because of insufficient macro-pulse duration of e-beam and FEL gain. The undulator of KU-FEL has been replaced with the undulator which was previously used for ERL-FEL in JAEA. The optical cavity has been replaced with optimized one. In addition the diameter of the coupling hole on the upstream cavity mirror has been reduced from 2 to 1 mm for reducing cavity loss. After installation, the tunable range of KU-FEL has been improved to 5-15 micro-m. Estimated FEL gain is greater than 30%, which was 1.5 times larger than original configuration.
*H. Zen, et al., Infrared Physics and Technology, Vol. 51, Issue 5, p.382 (2008)
**H. Ohgaki, et al., Proc. of FEL08, p.4 (2008)
***H. Ohgaki, et al., Proc. of FEL09, p.572 (2009)