The Physics Society of Iran Iranian Journal of Physics Research 1682-6957 20 2 2020 08 22 Simulation of pre-bunched free electron laser oscillator in the THz regime Simulation of pre-bunched free electron laser oscillator in the THz regime 187 193 1607 10.47176/ijpr.20.2.25731 FA F Bazouband 1. Department of Physics, Faculty of Science, Fasa University, Fasa, Iran E Mir 2. Department of Photonics, Faculty of Sciences and New Technologies, Graduate University of Advanced Technology, Kerman, Iran Journal Article 2018 10 09 One of the long-term objectives in the development of high gain free electron lasers (FEL) is to reduce the necessary electron beam voltage for a strong FEL interaction at a given frequency. FEL oscillators (FELOs) play the main role to this end. In this paper, the simulation of one dimensional FELO with planar wiggler is done at the applicable Tera-hertz regime. The effect of pre-bunched electron beam on the gain improvement or on the laser length is investigated. To study the evolution of system, a set of self-consistent nonlinear differential equations are solved numerically by the Runge-Kutta method and the averaging of electron beam is done by the Simpson method. One of the long-term objectives in the development of high gain free electron lasers (FEL) is to reduce the necessary electron beam voltage for a strong FEL interaction at a given frequency. FEL oscillators (FELOs) play the main role to this end. In this paper, the simulation of one dimensional FELO with planar wiggler is done at the applicable Tera-hertz regime. The effect of pre-bunched electron beam on the gain improvement or on the laser length is investigated. To study the evolution of system, a set of self-consistent nonlinear differential equations are solved numerically by the Runge-Kutta method and the averaging of electron beam is done by the Simpson method. https://ijpr.iut.ac.ir/article_1607_9597353e41e6957b5e7aa79214fcb256.pdf