Undergraduate Research at Jefferson Lab

Using a Magnetron to Drive a Superconducting RF Cavity

Student: Joshua Vega

School: College of William & Mary

Mentored By: Haipeng Wang

Jefferson Labs is presently researching magnetrons as an alternative high-power source of radio frequency (RF) radiation to drive its acceleration cavities. Magnetrons are more efficient at DC-to-RF power conversion, making magnetrons an attractive potential RF source. The purpose of this project was to demonstrate amplitude modulation and injection phase locking performance for a water-cooled magnetron; additionally, a pair of trim magnet coils were designed, constructed and installed to control noise levels. The I-V curve, efficiency, injection and output powers of the magnetron were measured. The trimmed magnetic field with modulation was surveyed and is to be installed on the magnetron body for greater noise control. The results of our experiment demonstrate that high power magnetrons can be feasibly controlled with a stable phase, variable amplitude, and fast noise suppression control. However, the presence of sideband noise requires further investigation, and the noise level may still be too high for SRF cavity applications. The control technology itself can be scaled up and applied to any other magnetron systems for the accelerator facility using other RF sources, potentially leading to more efficient and cost-effective accelerators.

[Watch the presentation on YouTube]