MRI: Development of the IsoDAR Front-end

该奖项资助开发射频四极杆（Radio Frequency Quadrupole，缩写为ERF），用作离子注入回旋加速器（一种粒子加速器）前端的一部分。其结果将是一个新颖的，完全工作的前端仪器，可用于多种目的。基于最初于1981年提出的概念，但从未实现，这将是第一次演示直接注入紧凑的高强度回旋加速器。该设计具有潜在的变革性，并有望在经典前端回旋加速器设计的聚束和注入效率上提高3-5倍。它更紧凑，成本相当，大大推进了加速器技术。计划中的加速器系统依赖于传统的、众所周知的、经过验证的技术。创新在于这些技术的结合。挑战在于，一方面，各种组件（来自源的电流，电流和传输，以及与回旋加速器的耦合）的单独性能的演示，另一方面，它们集成到一个紧凑的，高束流的，具有成本效益的质子驱动器前端。质子驱动器具有广泛的影响;它们是研究工具（中微子物理学，凝聚态研究的次级粒子，中子源），未来能源的工具等等。高强度回旋加速器的发展对工业有两个重要的影响。第一是增加放射性药物回旋加速器的能量、强度和多功能性。例如，回旋加速器的质子可以有效地产生锶-82，这对医学成像很重要。此外，这项工作还与加速器驱动系统（ADS）技术有关，例如，用于驱动钍反应堆，从而支持安全核能源的开发。电流提高5-10倍将对这些领域产生重大影响。前端的开发和运行将包括麻省理工学院的本科生、研究生和博士后。这将提供出色的教育体验，增加大学的加速器科学，并为年轻科学家提供更多的硬件经验。成功演示后，新的前端可以用于IsoDAR（同位素静止衰变）实验，该实验有可能提高我们对无菌中微子的认识，并揭示中微子观察到的几个异常。目标是利用H2+的双注入到紧凑型回旋加速器中。每个H2+离子在剥离后提供2个质子，从而将所需的束电流降低2倍并降低空间电荷力，克服了将强质子束注入回旋加速器中心区域的限制。在四极结构中，RF注入使用RF辐射作为通过提高聚束效率来减轻离子源要求的方法。直接耦合的效率的回旋加速器的螺旋偏转器注入通道（两个加速器之间的束匹配的问题）是系统集成的一个微妙的部分;它必须被证明，是该项目的目标。

This award funds the development of a Radio Frequency Quadrupole (RFQ) to be used as part of a front-end for ion injection into a cyclotron, a type of particle accelerator. The outcome will be a novel, fully-working front-end instrument that can be used for multiple purposes. Based on a concept originally introduced in 1981, but never realized, this will be the first demonstration of RFQ direct injection into a compact, high intensity cyclotron. The design is potentially transformative and promises a 3-5 times increase in efficiency of bunching and injection over classic front-end cyclotron designs. It is more compact and of comparable cost, significantly advancing accelerator technology. The accelerator system planned relies on conventional, well known, proven technologies. The innovation is in the combination of these technologies. The challenges are in the demonstration of, on one hand, the individual performances of the various components (the current from a source, RFQ and transmission, and coupling to the cyclotron) and, on the other hand, their integration into a compact, high beam current, cost-effective proton driver front-end. Proton drivers have a broad impact; they are research tools (for neutrino physics, secondary particles for condensed matter research, neutron sources), tools for the future of energy, and more. The development of high intensity cyclotrons has two important impacts for industry. The first is to increase the energy, intensity and versatility of radiopharmaceutical cyclotrons. Protons from a cyclotron can, for example, efficiently produce Strontium-82, important for medical imaging. In addition, this work also has relevance to Accelerator Driven Systems (ADS) technology, applied, for example, to driving thorium reactors, thus supporting the development of safe nuclear energy sources. A factor of 5-10 improvement in current would have a significant impact in these areas. The development and running of the front-end will include MIT undergraduates, graduate students, and postdocs. This will provide an excellent educational experience, with increased accelerator science at universities and more hardware experience for young scientists. Upon successful demonstration, the new front-end could be used in the IsoDAR (Isotope Decay-At-Rest) experiment which has the potential to advance our knowledge about sterile neutrinos and shed light on several anomalies observed with neutrinos.The goal is to make use of RFQ injection of H2+ into a compact cyclotron. Each H2+ ion provides 2 protons after stripping thus reducing the necessary beam current by a factor of 2 and reducing space-charge forces, overcoming the limitations of injecting an intense proton beam into the cyclotron central region. The RFQ injection uses RF radiation in a quadrupole structure as a method to alleviate the ion source requirements by improving the bunching efficiency. The efficiency of the direct coupling of the RFQ to the spiral inflector injection channel of the cyclotron (a matter of bunch matching between the two accelerators) is a delicate part of system integration; it has to be demonstrated and is a goal of the project.