Resonant Polarimetry and Magnetometry

The next generation DOE physics accelerator, The Electron Ion Collider (EIC) will collide spin oriented electrons and ions with unprecedented focus at the interaction point. For accelerator operators to maintain these spin polarized beams they must have a way to noninvasively measure spin orientation as the beam travels through the accelerator. To achieve the unprecedented focus at the collision point, a magnetized beam of electrons will be recycled to cool the ions and improve their focus. To manage and maintain this magnetized beam, accelerator operators need non-invasive real-time beam magnetometers. Accelerator operators and designers currently do not have real time, non-invasive polarization monitors, or bunch magnetometers, and no direct way to automate polarization quality optimization or beam magnetization in real time. The Thomas Jefferson National Laboratory (JLAB), Cornell’s Laboratory of Elementary-Particle Physics (LEPP) and, Electrodynamic, have joined together in a collaboration dedicated to finding solutions to this urgent need. During phase I a prototype resonant polarimeter was installed on CEBAF and beam measurement with it using a phase sensitive receiver were extremely informative but inconclusive. The experience defined the experimental challenges and informed the design and development of new experimental apparatus that was constructed during Phase I and will be installed at JLAB in the first months of Phase II. Since Phase I concluded, two new beamlines have become available for testing resonant polarimeters and magnetometers. A polarized beam line at Jlab’s Upgrade Injector Test Stand and a magnetized beamline on Jlab’s Gun test stand (GTS). Experiments are planned at both of these facilities and again at CEBAF during this Phase II. This Phase II SBIR will develop non-invasive, real-time, resonant polarimeters and magnetometers that will improve the optimization and control of spin polarized and magnetized beams. Commercial Applications: Low-noise phase sensitive receivers have many applications in charged particle acceleration including polarimetery and high resolution beam position monitoring. The hardware in development has applications in several facilities.