Optical Properties of Cold Dense Electron-Positron Plasmas

中性等离子体是由相同数量的带正电荷和带负电荷的粒子组成的气体。这个项目涉及等离子体物理研究的一个前沿，在这个前沿中，两个电荷，负电子和正电子，是彼此的反粒子，具有完全相同的质量和相反的电荷。这类系统的简单行为将对理解和控制使用未来聚变能源技术发电所需的非等质量等离子体具有重要价值。等质量电子-正电子等离子体将在不同的密度和温度条件下进行检验，以验证其预测的比非等质量等离子体更大的稳定性。这项研究将在联邦指定的西班牙裔服务机构进行，随着时间的推移，将为本科生、研究生和博士后培训创造机会，从而支持校园和国家的教育和多样性目标。这一探索性项目的目标是演示极化正负电子等离子体在镶嵌在钻石等固体中的不同大小的腔中的捕获。短短10纳秒的~107个正电子爆发将通过一个薄窗口传递到空腔中。正电子将被固体的化学势所排斥，它们将吸引在注入过程中释放的同等数量的“热”电子。中性电子-正电子等离子体将在腔内积聚，并在常温下迅速平衡。等离子体的极化、温度和密度将从湮没速率和脉冲激发引起的等离子体振荡中推导出来。由于不存在由不等质量引起的不稳定性，等质量等离子体是探索其他可能与腔体几何形状或阻抗相关的不稳定性的理想系统。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。

A neutral plasma is a gas composed of equal numbers of particles with positive and negative charges. This project addresses a frontier in plasma physics research in which the two charges, negative electrons and positive positrons, are each other’s antiparticles, with exactly equal masses and opposite charges. The simpler behavior of this type of system will be of great value in the understanding and control of the non-equal mass plasmas required for power generation using future fusion energy technologies. The equal mass electron-positron plasma will be examined under various conditions of density and temperature to verify its predicted greater stability compared to the non-equal mass plasmas. This research will occur at a federally-designated Hispanic Serving Institution and over time will create opportunities for undergraduate, graduate, and postdoctoral training, thus supporting the education and diversity goals of the campus and the Nation.The goal of this exploratory project is to demonstrate the trapping of polarized electron-positron plasmas in cavities of various sizes from 1 mm to 50 micron embedded in a solid such as diamond. Short, 10 nanosecond, bursts of ~107 positrons will be delivered to the cavities through a thin window. The positrons will be repelled by the chemical potential of the solid, and they will attract an equal number of “hot” electrons released during the implantation. A neutral electron-positron plasma will build up in the cavity and rapidly equilibrate at a common temperature. The plasma polarization, temperature, and density will be deduced from the annihilation rate and from plasma oscillations induced by pulsed excitation. Being devoid of the instabilities that come from unequal mass, the equal mass plasma is the ideal system to explore other instabilities that might be associated with cavity geometry or impedance.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.