Fig. 4

Evidence for proton energization in the collision of two fast plasmas in an ambient magnetic field. Proton spectra as recorded by the Thomson Parabola. Several spectra corresponding to unmagnetized shots are shown: a single foil irradiated with the L1 laser beam only (diamonds) and two foils irradiated with both beams (circles). Two duplicate shots with both foils and a 20 T imposed B-field (squares, triangles) are also shown. Error bars correspond to the noise level on the image plate diagnostic