[17p-A501-1~12] 3.5 Ultrashort-pulse and high-intensity lasers (formerly 3.6)

▲ [17p-A501-7] BISER experiments with the Astra and J-KAREN-P lasers

〇Alexander Pirozhkov¹, A.N. Shatokhin², A. Sagisaka¹, K. Ogura¹, T.A. Pikuz³, A.V. Kotov⁴, T. Dzelzainis⁵, A. Bierwage¹, Ko. Kondo¹, H. Ohiro⁶, S. Lorenz⁷, Y.-K. Liu⁸, G.M. Grittani⁷, T.M. Jeong⁷, N. Nakanii¹, K. Huang¹, A. Kon¹, Y. Miyasaka¹, G. Hull⁵, S. Dann⁵, E.A. Vishnyakov⁷, A.O. Kolesnikov², M. Koike¹, P. Chen⁸, T.Zh. Esirkepov¹, J.K. Koga¹, R. Gray⁹, A.A. Soloviev⁴, E.N. Ragozin², S.V. Bulanov⁷ (1.QST, 2.LPI RAS, 3.Osaka Univ., 4.IAP RAS, 5.CLF RAL, 6.Hiroshima Univ., 7.ELI Beamlines, 8.Nat. Taiwan Univ., 9.Strathclyde Univ.)

Keywords:Ultrabright coherent x-ray source, Relativistic laser plasma, Burst Intensification by Singularity Emitting Radiation (BISER)

BISER is an ultrabright temporally&spatially coherent x-ray source. We performed BISER experiments with the Astra and J-KAREN-P lasers.
As reported earlier, in the 7 TW Astra experiment we obtained unusually bright ~μJ pulses (17-34nm range, 0.3°×0.2° acceptance angle). Understanding bright coherent x-ray generation physics is an outstanding scientific problem. Here we report on our efforts to perform time-resolved diagnostics of relativistic plasma singularities.
Another outstanding task is to measure the total BISER pulse energy, for which we need to know its near-axis angular distribution. This requires placing x-ray diagnostics close to the interaction point. The challenge is to avoid x-ray filter damage and multi-TW laser focusing onto an x-ray CCD. In the J-KAREN-P experiment, we performed filter damage threshold studies, followed by the damage-free BISER angular distribution measurements in the ±2.5° cone. It showed that under optimum conditions BISER had ~100μJ pulses.