Author/Authors :
Esirkepov، نويسنده , , Timur Zh. and Koga، نويسنده , , James K. and Sunahara، نويسنده , , Atsushi and Morita، نويسنده , , Toshimasa and Nishikino، نويسنده , , Masaharu and Kageyama، نويسنده , , Kei and Nagatomo، نويسنده , , Hideo and Nishihara، نويسنده , , Katsunobu and Sagisaka، نويسنده , , Akito and Kotaki، نويسنده , , Hideyuki and Nakamura، نويسنده , , Tatsufumi and Fukuda، نويسنده , , Yuji and Okada، نويسنده , , Hajime and Pirozhkov، نويسنده , , Alexander S. and Yogo، نويسنده , , Akifumi and Nishiuchi، نويسنده , , Mamiko and Kiriyama، نويسنده , , Hiromitsu and Kondo، نويسنده , , Kiminori and Kando، نويسنده , , Masaki and Bulanov، نويسنده , , Sergei V.، نويسنده ,
Abstract :
When a finite contrast petawatt laser pulse irradiates a micron-thick foil, a prepulse (including amplified spontaneous emission) creates a preplasma, where an ultrashort relativistically strong portion of the laser pulse (the main pulse) acquires higher intensity due to relativistic self-focusing and undergoes fast depletion transferring energy to fast electrons. If the preplasma thickness is optimal, the main pulse can reach the target accelerating fast ions more efficiently than an ideal, infinite contrast, laser pulse. A simple analytical model of a target with preplasma formation is developed and the radiation pressure dominant acceleration of ions in this target is predicted. The preplasma formation by a nanosecond prepulse is analyzed with dissipative hydrodynamic simulations. The main pulse interaction with the preplasma is studied with multi-parametric particle-in-cell simulations. The optimal conditions for hundreds of MeV ion acceleration are found with accompanying effects important for diagnostics, including high-order harmonics generation.
Keywords :
Petawatt laser , Laser-matter interaction , Ion acceleration , Plasma Diagnostics , Relativistic high order harmonic , Laser pulse contrast
