论文标题
通过激光驱动的锥形目标产生明亮的准直涡流$γ$ ray
Generation of bright collimated vortex $γ$-ray via laser driven cone-fan target
论文作者
论文摘要
我们使用数值模拟来证明，可以通过照射强度约为$ 10^{22} \ rm {w/{w/{cm^2} $上的圆形极化激光来实现明亮的准直涡流$γ$ - 具有大轨道角动量的源。在研究的设置中，形成了数百个MEV和涡流激光脉冲的电子束。此外，产生高质量的涡旋$γ$ ray，$ 5^{\ circ} $和高峰光彩$ \ sim5 \ sim5 \ times10^{22} $ photons $ {\ rm \ rm \ rm \ rm \ cdot s^{ - 1}} $ 0.1 \％\ mathrm {bw} $ at $ 10 \ mathrm {mev} $。激光的角度动量很大一部分被转换为电子束和涡流$γ$ - 雷，分别为$ 27.8 \％$和$ 3 \％$。从激光到电子束和涡流$γ$ - 雷的能源转换效率约为$ 41 \％$ $和$ 3.8 \％$。此外，针对不同圆锥右半径的比较模拟表明，存在最佳尺寸，使最高的角动量$γ$ - 雷光子的光子约为$ 2.8 \ times10^6 \ hbar $。不同激光模式的比较模拟表明，选择循环极化激光比laguerre-gaussian更合适。
We use numerical simulations to demonstrate that a source of bright collimated vortex $γ$-ray with large orbital angular momentum can be achieved by irradiating a circularly polarized laser with an intensity about $10^{22}\rm{W/{cm^2}}$ on a cone-fan target. In the studied setup, electron beam of energy of hundreds of MeV and vortex laser pulse are formed. And furthermore a high quality vortex $γ$-ray is yielded with small divergence of $5^{\circ}$ and high peak brilliance $\sim5\times10^{22}$ photons ${\rm\cdot s^{-1} \cdot mm^{-2} \cdot mrad^{-2}}$ $0.1\%\mathrm{BW}$ at $10\mathrm{MeV}$. A considerable fraction of angular momentum of laser is converted to electron beam and vortex $γ$-ray, which are roughly $27.8\%$ and $3\%$, respectively. And the conversion efficiency of energy from laser to electron beam and vortex $γ$-ray are around $41\%$ and $3.8\%$. Moreover, comparative simulations for different right radius of cone reveal that there exists an optimal size that makes the highest angular momentum of $γ$-ray photons to be around $2.8\times10^6\hbar$. The comparative simulations for different laser modes exhibit that it is more appropriate to choose the circularly polarized laser to generate vortex $γ$-ray than the Laguerre-Gaussian one.
