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Growth rate for free-electron lasers through a warm beam layered model

Published online by Cambridge University Press:  16 June 2016

E. Peter*
Affiliation:
Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, 91501-970, Porto Alegre, RS, Brasil
F. B. Rizzato
Affiliation:
Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, 91501-970, Porto Alegre, RS, Brasil
A. Endler
Affiliation:
Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, 91501-970, Porto Alegre, RS, Brasil
*
Email address for correspondence: [email protected]

Abstract

In the present work, we describe the linear growth rate of the laser field for a one-dimensional theoretical single-pass free-electron laser, including space-charge and thermal effects, in the hydrodynamical regime. In a recent work (Peter, Endler & Rizzato, Phys. Plasmas, vol. 21, 2014, 113104), the thermal effects were already included for a water-bag initial distribution for the longitudinal velocities of the particles of the beam. Here, we extend the result for different and symmetrical initial distributions, considering that in the hydrodynamical regime, the beam can be thought of as a warm fluid composed of a sum of different fluids with different densities, where the initial distribution of each fluid is a water-bag distribution. The total pressure of the beam is related to the sum of the pressures of these fluids. This approach is much less complicated than the kinetic approach. We compare the results given by the linear set of equations and wave–particle simulations for water-bag and Gaussian initial distributions. The evolution of the particle distribution in the phase space is also shown in order to demonstrate that the assumption of the sum of different fluids reproduces the physics of the system in a reasonable fashion.

Type
Research Article
Copyright
© Cambridge University Press 2016 

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References

Babaei, S. & Maraghechi, B. 2008 Plasma-loaded free-electron laser with thermal electron beam and background plasma. Phys. Plasmas 15 (1), 013102.Google Scholar
Bonifacio, R., Casagrande, F., Cerchoni, G., de Salvo Souza, L., Pierini, P. & Piovella, N. 1990 Physics of the high-gain FEL and superradiance. Riv. del Nuovo Cimento 13 (9), 169.Google Scholar
Brau, C. 1990 Free-Electron Lasers. Academic.Google Scholar
Chakhmachi, A. & Maraghechi, B. 2009 Stability properties of free-electron laser in Raman regime with thermal electron beam. Phys. Plasmas 16 (4), 043110.Google Scholar
Coffey, T. P. 1971 Breaking of large amplitude plasma oscillations. Phys. Fluids 14 (7), 14021406.CrossRefGoogle Scholar
Freund, H. P. & Antonsen, T. M. 1996 Principles of Free-Electron Lasers. Chapman & Hall.Google Scholar
Freund, H. P., Davidson, R. C. & Kirkpatrick, D. A. 1991 Thermal effects on the linear gain in free-electron lasers. IEEE J. Quant. Electron. 27 (12), 25502559.Google Scholar
Ibanez, L. & Johnston, S. 1983 Finite-temperature effects in free-electron lasers. IEEE J. Quant. Electron. 19 (3), 339346.Google Scholar
Marshall, T. C. 1985 Free-Electron Lasers. Macmillan.Google Scholar
Monteiro, L. F., Serbeto, A., Tsui, K. H., Mendonça, J. T. & Galvão, R. M. O. 2013 Quantum fluid model of coherent stimulated radiation by a dense relativistic cold electron beam. Phys. Plasmas 20 (7), 073101.Google Scholar
Murphy, J. B., Pellegrini, C. & Bonifacio, R. 1985 Collective instability of a free electron laser including space charge and harmonics. Opt. Commun. 53 (3), 197202.Google Scholar
Peter, E., Endler, A. & Rizzato, F. B. 2014 Nonlinear model for thermal effects in free-electron lasers. Phys. Plasmas 21 (11), 113104.Google Scholar
Peter, E., Endler, A., Rizzato, F. B. & Serbeto, A. 2013 Mixing and space-charge effects in free-electron lasers. Phys. Plasmas 20 (12), 123104.CrossRefGoogle Scholar
Seo, Y. & Choi, E. H. 1997 A submillimeter Raman free-electron laser in a dense plasma background. IEEE Trans. Plasma Sci. 25 (2), 360363.Google Scholar
Sprangle, P., Tang, C.-M. & Manheimer, W. M. 1980 Nonlinear theory of free-electron lasers and efficiency enhancement. Phys. Rev. A 21, 302318.CrossRefGoogle Scholar
Wang, M., Xiao, X. & Liang, Z. 2006 Nonlinear study on Raman regime free electron laser with elliptical waveguide. J. Phys. D: Appl. Phys. 39 (15), 3332.Google Scholar