Relativistic positron production with ultra-intense short-pulse lasers

Ultra-intense laser interactions with solid foils are studied as a means to produce relativistic positron plasmas, which has been proposed as a potential laboratory for understanding positron-electron plasma aspects of gamma-ray bursts [1]. Initial experiments with high energy Nd:glass lasers have revealed a strong dependence of the positron yield, and energy distribution, on the thin-foil target thickness [2]. This arises from the contribution of so-called “trident” electro-production positrons, beyond the photo-production which dominates in thick targets [3]. Prospects for thin-target positron production and detection in 100 TW-class ultra-short pulse laser experiments will be presented

References
[1] E.P. Liang, S.C. Wilks and M. Tabak, Phys. Rev. Lett. 81, 4887 (1998).
[2] T. E. Cowan et al., Laser Part. Beams 17, 773 (1999).
[3] H. Chen et al., Phys. Rev. Lett. 102, 105001 (2009).