| Paper | Title | Page |
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| MOPC17 | Harmonic Undulator Radiation and FEL Gain with Two-Peak Electron Beam Energy Distribution | 75 |
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In the recent past harmonic undulators[1-4] are proposed for enhancced free electron laser radiation at higher harmonics. In this paper we include the important influence of beam energy spread on harmonic undulator radiation. A two-peak electron beam energy distribution[5]is considered to enhance the spectrum broadening and gain reduction in the harmonic undulator free electron laser. [1] Jeeva Khan Hussain, Vikesh Gupta, G.Mishra, IL Nuovo Cimento B, In Press 2009. |
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| MOPC18 | Three-Frequency Undulator Radiation and Free-Electron Laser Gain | 79 |
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A new three frequency undulator has been proposed.[1] The authors assume that the electron moves on axis in a three harmonic undulator structure. Let us consider the case of the fundamental. The intensity at this frequency will be further enhanced by the contribution from the modulation at sum-difference frequencies. The fundamental intensity will be raised. For the next odd harmonics of the fundamental, there will be contributions from the harmonic field components to produce an enhanced intensity at the third odd harmonics. At this frequency there will be further contributions from the sum-frequency. However the intensity contributions from the sum-difference frequency will be small in comparison to the primary odd harmonics and the net result is that the third harmonic intensity will be raised . Thus the three frequency works in a similar way to that of the harmonic undulator scheme. In this paper we calculate the three frequency undulator radiation and discuss the feasibility of free electron laser operation with this undulator scheme. [1] V.I.R. Niculescu et al. Rom Journ. Phy. Vol.53, Nos.5-6, P.775-780 (2008) |
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| MOPC19 | Variable Polarized Harmonic Undulator Free Electron Laser and Effect of Beam Energy Spread | 83 |
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In the recent past, variable polarized undulators and variable polarized harmonic undulator [1-4] are proposed. The scheme consists of two identical linearly polarized magnets with high permeability shims in the gap of the undulator magnets. In this paper we include the important effects of beam energy spread on the variable polarized harmonic undulator radiation and discuss free electron laser gain. We have considered both single and two peak gaussian beam energy distribution to calculate intensity and gain reduction. We show that the variable polarized harmonic undulator scheme compensates the undesired effects of the beam energy spread in comparison to the standard variable polarized undulator free electron laser. [1] G. Dattoli, L. Bucci, Nuclear Instruments and Methods in Phy. Res. A, vol.450(2000)p-479. |