Long-range attraction of an ultrarelativistic electron beam by a column of neutral plasma

E. Adli (1) , C A Lindstrøm (1) , J Allen (2) , C. Clarke (2) , J. Frederico (2) , S. Gessner (2) , S. Green (2) , M J Hogan (2) , M D Litos (2) , B O'Shea (2) , V. Yakimenko (2) , W An (3) , C E Clayton (3) , K A Marsh (3) , W B Mori (3) , C. Joshi (3) , N. Vafaei-Najafabadi (3) , Sébastien Corde (4) , W Lu (5)

1 Department of Physics [Oslo]
2 SLAC - SLAC National Accelerator Laboratory
3 UCLA - University of California [Los Angeles]
4 LOA - Laboratoire d'optique appliquée
5 Department of Engineering Physics, Tsinghua University

We report on the experimental observation of the attraction of a beam of ultrarelativistic electrons towards a column of neutral plasma. In experiments performed at the FACET test facility at SLAC we observe that an electron beam moving parallel to a neutral plasma column, at an initial distance of many plasma column radii, is attracted into the column. Once the beam enters the plasma it drives a plasma wake similar to that of an electron beam entering the plasma column head-on. A simple analytical model is developed in order to capture the essential physics of the attractive force. The attraction is further studied by 3D particle-in-cell numerical simulations. The results are an important step towards better understanding of particle beam–plasma interactions in general and plasma wakefield accelerator technology in particular.

Mots clés: electron beams; plasma physics; plasma wakefield acceleration; transverse beam dynamics; FACET user facility

Domaines: Physique des plasmas [physics.plasm-ph]

E. Adli, C A Lindstrøm, J Allen, C. Clarke, J. Frederico, et al.. Long-range attraction of an ultrarelativistic electron beam by a column of neutral plasma. New Journal of Physics, 2016, 18 (10), pp.103013 - 103013. ⟨10.1088/1367-2630/18/10/103013⟩. ⟨hal-01612782⟩