Betatron radiation from density tailored plasmas

Kim Ta Phuoc (1) , E. Esarey (2, 3) , V. Leurent (2) , E. Cormier-Michel (2, 3) , C. G. R. Geddes (2) , C. B. Schroeder (2) , Antoine Rousse (1) , W. P. Leemans (2, 3)

1 LOA - Laboratoire d'optique appliquée
2 LBNL - Lawrence Berkeley National Laboratory [Berkeley]
3 Department of Physics [Reno]

In laser wakefield accelerators, electron motion is driven by intense forces that depend on the plasma density. Transverse oscillations in the accelerated electron orbits produce betatron radiation. The electron motion and the resulting betatron radiation spectrum can therefore be controlled by shaping the plasma density along the orbit of the electrons. Here, a method based on the use of a plasma with a longitudinal density variation (density depression or step) is proposed to increase the transverse oscillation amplitude and the energy of the electrons accelerated in a wakefield cavity. For fixed laser parameters, by appropriately tailoring the plasma profile, the betatron radiation emitted by these electrons is significantly increased in both flux and energy.

Keywords: plasma accelerators; plasma density; plasma oscillations

Domains: Plasma Physics [physics.plasm-ph]

Kim Ta Phuoc, E. Esarey, V. Leurent, E. Cormier-Michel, C. G. R. Geddes, et al.. Betatron radiation from density tailored plasmas. Physics of Plasmas, 2008, 15 (6), pp.063102. ⟨10.1063/1.2918657⟩. ⟨hal-00573304⟩