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arXiv · 1310.6164

Bright gamma-rays from betatron resonance acceleration in near critical density plasma

B. Liu·H. Y. Wang·D. Wu·J. Liu·C. E. Chen·X. Q. Yan·X. T. He
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Abstract

We show that electron betatron resonance acceleration by an ultra-intense ultra-short laser pulse in a near critical density plasma works as a high-brightness gamma-ray source. Compared with laser plasma X-ray sources in under-dense plasma, near critical density plasma provides three benefits for electron radiation: more radiation electrons, larger transverse amplitude, and higher betatron oscillation frequency. Three-dimensional particle-in-cell simulations show that, by using a 7.4J laser pulse, 8.3mJ radiation with critical photon energy 1MeV is emitted. The critical photon energy $E_c$ increases with the incident laser energy %faster than a linear relation. $W_I$ as $E_c \propto W_I^{1.5}$, and the corresponding photon number is proportional to $W_I$. A simple analytical synchrotron-like radiation model is built, which can explain the simulation results.

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B. Liu, H. Y. Wang, D. Wu, J. Liu, C. E. Chen, X. Q. Yan, X. T. He. 2013-10-23. Bright gamma-rays from betatron resonance acceleration in near critical density plasma. https://arxiv.org/abs/1310.6164

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