Probing Super-Critical Electromagnetic Fields with Petawatt Lasers

该项目支持为国家科学基金会资助的新的高强度Zettawt当量超短脉冲激光系统(ZEUS)设施设计实验的努力。高峰值功率的激光器，如宙斯多拍瓦特激光器，可以通过将能量聚焦到一个微小的光点来产生极端的电磁场。这些场能够在十亿分之一秒内将带电粒子加速到接近光速，产生明亮的点状辐射源。在这样的强场中，高能伽马射线可以自发衰变成成对的物质-反物质粒子，导致物质从光中产生。该项目将为宙斯实验室设计实验，通过连锁反应测量物质的创造和放大过程。该项目将支持研究生，并将使研究密集和超短持续时间的反物质光束成为可能。Zeus激光设备将通过激光尾场加速产生几吉电子伏的电子束，这是一种在高功率超短脉冲激光之后利用等离子体中产生的加速场结构产生电子束的方法。通过将电子束与第二个紧聚焦的高功率激光脉冲碰撞，场强有望大大超过电子静止坐标系中的量子电动力学临界场，从而产生电子-正电子对。研究生将参与设计和制造用于Zeus实验的粒子探测器，用于控制稳定的单能光束注入和引导激光实现多GeV能量的等离子体目标，并使用先进的量子动力学代码对激光-电子碰撞物理进行建模。了解激光相互作用物理对于前沿宙斯实验的成功至关重要。在该项目的最后一年，预计与宙斯一起的激光时间将用于这一前沿实验的第一次运行。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project supports efforts to design experiments for the new National Science Foundation-funded high intensity Zettawatt-Equivalent Ultrashort pulse laser System (ZEUS) facility. High peak-power lasers, such as the ZEUS multi-Petawatt laser can generate extreme electromagnetic fields through focusing the power down to a tiny spot. These fields are capable of accelerating charged particles to near the speed of light in a fraction of a million billionth of a second, producing bright, point-like sources of radiation. In such strong fields, high-energy gamma-rays can spontaneously decay into pairs of matter-antimatter particles, leading to matter creation from light. This project will design experiments for the ZEUS facility to measure matter creation and amplification of the process through a chain reaction. The project will support graduate students and should enable a study of dense and ultrashort duration beams of antimatter.The ZEUS laser facility will generate few-gigaelectronvolt electron beams through laser wakefield acceleration, which is a method for generating beams of electrons using the accelerating field structure produced in a plasma in the wake of a high-power, ultrashort pulsed laser. By colliding the electron beam with a second, tightly focused, high-power laser pulse, the field strength is expected to greatly exceed the critical field of quantum electrodynamics in the electron rest frame, leading to electron-positron pair production. Graduate students will participate in designing and building particle detectors for ZEUS experiments, the plasma target for controlled injection of stable monoenergetic beams and guiding of the laser to achieve multi-GeV energies, and modelling the laser-electron collision physics using advanced quantum kinetic codes. Understanding the laser interaction physics is crucial for the frontier ZEUS experiments to be successful. In the final year of the project, laser time with ZEUS is anticipated to be available for the first runs for this frontier experiment.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.