基于激光等离子体的X/γ辐射研究进展

Research progress of X/γphoton emission in laser-plasma interaction

随着激光技术的不断发展,激光功率突破10 PW量级,激光与物质相互作用进入近量子电动力学(QED)范畴。从弱相对论激光到相对论激光再到强相对论激光,激光场与物质的耦合可以产生能量从keV到MeV甚至GeV的X/γ射线。这些辐射具有通量大、亮度高、能量高和脉宽短等特点,在核物理、高能量密度物理、天体物理等基础研究以及材料科学、成像、医学等领域具有广泛应用前景。系统梳理了近年来相对论强激光与气体、近临界密度等离子体及固体靶相互作用,通过诸如同步辐射、betatron和类betatron辐射、Thomson散射和非线性Compton散射过程等产生高能X/γ射线的最新研究进展,总结了各种方案产生的X/γ射线的品质因子和潜在应用,并为下一步基于强激光大科学装置的实验研究提供理论参考。

With the continuous development of technology,the laser power has exceeded 10 PW.The interaction between such intense laser pulse and matter enters the near quantum electrodynamics(QED)regime.From the non-relativistic laser pulse,relativistic one,to ultra-relativistic one,the coupling of light field and matter can produce X/γ-rays with the photon energy from keV,MeV to even GeV.These radiation sources have the characteristics of large flux,high brilliance,high energy and short duration,which have a wide range of application prospects in material science,imaging,and medicine fields and fundamental researches in nuclear physics,high-energy-density physics and astrophysics.In this review,we systematically introduce the recent advances in X/γ-ray generation through the interaction of relativistic high intensity laser with gas,near-critical-density plasma and solid targets via synchrotron radiation,betatron radiation,betatron-like radiation,Thomson scattering and nonlinear Compton scattering.The characteristics and potential applications of high energy X/γ-ray from various schemes are also summarized,which provide theoretical reference for the future experimental researches based on laser facilities.