Establishing Limits for Positron Plasmas - -- Long Term Storage, Large Particle Numbers, and Cold Beams

涉及正电子（即电子的反粒子）的现象在许多领域都很重要，包括天体物理学、等离子体和原子物理学以及材料科学。最近，通过利用非中性等离子体技术的实验室实验，这些领域取得了很大进展。该提案描述了一项研究计划，旨在创建和理解参数空间新区域中单组分正电子等离子体新状态的物理学。该研究的一个关键等离子体物理重点是理解和优化单组分等离子体的径向压缩、扭矩平衡、稳态。这些状态是通过平衡不对称引起的膨胀和加热与旋转场压缩和回旋加速器冷却而产生的。该项目将使用低温高磁场陷阱来形成正电子等离子体和束流。近期目标是在超高真空环境中长期限制（即数天）= 1010 个正电子数天，并产生能量扩散小至 1 meV 的正电子束和新一代静电正电子束。这项工作中开发的高容量陷阱将用于开发多单元陷阱，以将正电子存储容量增加几个数量级。这项研究中开发的等离子体和束预计将产生广泛的科学和技术影响。应用包括电子-正电子等离子体的研究、用于基础物理测试的低能反氢原子、材料表征、原子物理、天体物理建模、反物质的长期存储以及最终便携式反物质陷阱的开发。该项目将成为优秀的科技人才培养基地。它将涉及研究生和博士后研究人员，包括各级代表性不足的群体的成员。 研究团队成员经常就研究的实际意义向学术和工业研究人员提供建议。他们开发的正电子陷阱和束现已在世界各地的许多实验室中使用。

Phenomena involving positrons (i.e., the antiparticles of electrons) are important in many fields including astrophysics, plasma and atomic physics, and materials science. Much progress has been made recently in these areas through laboratory experiments that exploit non-neutral plasma techniques. This proposal describes a program of research to create and understand the physics of novel states of single-component positron plasmas in new regions of parameter space. A key plasma physics focus of the research is understanding and optimizing radially compressed, torque-balanced, steady states of single component plasmas. These states are created by balancing asymmetry-induced expansion and heating with rotating-field compression and cyclotron cooling. This project will use a cryogenic, high-magnetic-field trap for positron plasma and beam formation. A near-term goal is long-term confinement (i.e., days) of = 1010 positrons in an ultra-high vacuum environment for days and the creation of positron beams with an energy spread as small as 1 meV and a new generation of electrostatic positron beams. The high-capacity trap developed in this work will be used to develop a multi-cell trap to increase positron storage capacity by additional orders of magnitude. The plasmas and beams developed in this research can be expected to have broad scientific and technological impact. Applications include study of electron-positron plasmas, the creation of low-energy anti-hydrogen atoms for tests of fundamental physics, materials characterization, atomic physics, astrophysical modeling, long term storage of antimatter, and eventually, the development of portable antimatter traps. This project will be an excellent training ground for scientific and technical personnel. It will involve graduate student and post-doctoral researchers, including members of underrepresented groups at all levels. Members of the research team frequently advise academic and industrial researchers on practical implications of the research. The positron traps and beams that they have developed are now used in a number of laboratories throughout the world.