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arXiv · 1310.2755

Evidence of resonant surface wave excitation in the relativistic regime through measurements of proton acceleration from grating targets

T. Ceccotti·V. Floquet·A. Sgattoni·A. Bigongiari·O. Klimo·M. Raynaud·C. Riconda·A. Heron·F. Baffigi·L. Labate·L. A. Gizzi·L. Vassura·J. Fuchs·M. Passoni·M. Kveton·F. Novotny·M. Possolt·J. Prokupek·J. Proska·J. Psikal·L. Stolcova·A. Velyhan·M. Bougeard·P. D'Oliveira·O. Tcherbakoff·F. Reau·P. Martin·A. Macchi
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Abstract

The interaction of laser pulses with thin grating targets, having a periodic groove at the irradiated surface, has been experimentally investigated. Ultrahigh contrast ($\sim 10^{12}$) pulses allowed to demonstrate an enhanced laser-target coupling for the first time in the relativistic regime of ultra-high intensity $>10^{19} \mbox{W/cm}^{2}$. A maximum increase by a factor of 2.5 of the cut-off energy of protons produced by Target Normal Sheath Acceleration has been observed with respect to plane targets, around the incidence angle expected for resonant excitation of surface waves. A significant enhancement is also observed for small angles of incidence, out of resonance.

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T. Ceccotti, V. Floquet, A. Sgattoni, A. Bigongiari, O. Klimo, M. Raynaud, C. Riconda, A. Heron, F. Baffigi, L. Labate, L. A. Gizzi, L. Vassura, J. Fuchs, M. Passoni, M. Kveton, F. Novotny, M. Possolt, J. Prokupek, J. Proska, J. Psikal, L. Stolcova, A. Velyhan, M. Bougeard, P. D'Oliveira, O. Tcherbakoff, F. Reau, P. Martin, A. Macchi. 2013-10-10. Evidence of resonant surface wave excitation in the relativistic regime through measurements of proton acceleration from grating targets. https://doi.org/10.1103/physrevlett.111.185001

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