论文标题
激光等离子体加速超明显电子束,可有效激发核异构体
Laser plasma accelerated ultra-intense electron beam for efficiently exciting nuclear isomers
论文作者
论文摘要
利用激光等离子体Wakefield来加速超高电荷电子光束对于许多开创性应用至关重要,例如,有效地生产出可能被广泛使用的寿命短的核异构体。但是,由于束负载效果,单个等离子体气泡中的电子电荷在数百个picocoulomb的水平上受到限制。在这里,我们通过实验表明,通过在密集的等离子体中的紧密焦点强烈的激光脉冲横向匹配,由一系列韦克菲尔德加速器链产生了一百公斤,二十纳米龙,数十个MEV准直的电子束。这种超明显的电子束归因于一种新型有效注入,即氮原子内壳电子被电离并连续注入多个等离子体气泡。通过光核反应,这种强烈的电子束已用于令人兴奋的核异构体,其超高峰值效率为$ 1.76 \ times10^{15} $颗粒/s。这种有效的异构体生产方法可广泛用于泵送具有激发态寿命的同位素降低到皮秒,这对于了解核过渡机制和刺激伽马射线激光器是有益的。
Utilizing laser plasma wakefield to accelerate ultra-high charge electron beam is critical for many pioneering applications, for example to efficiently produce nuclear isomers with short lifetimes which may be widely used. However, because of the beam loading effect, electron charge in a single plasma bubble is limited in level of hundreds picocoulomb. Here, we experimentally present that a hundred kilo-ampere, twenty nanocoulomb, tens of MeV collimated electron beam is produced from a chain of wakefield acceleration, via a tightly focused intense laser pulse transversely matched in dense plasma. This ultra-intense electron beam ascribes to a novel efficient injection that the nitrogen atom inner shell electrons are ionized and continuously injected into multiple plasma bubbles. This intense electron beam has been utilized to exciting nuclear isomers with an ultra-high peak efficiency of $1.76\times10^{15}$ particles/s via photonuclear reactions. This efficient production method of isomers can be widely used for pumping isotopes with excited state lifetimes down to picosecond, which is benefit for deep understanding nuclear transition mechanisms and stimulating gamma-ray lasers.