Progress Report on the NBS/LOS Alamos RTM

The NBS-Los Alamos 200 MeV Racetrack Microtron (RTM) is being built under a program aimed at developing the technology needed for high-current intermediateenergy CW electron accelerators. In this report we give an overview of the present status of the project. Recent progress includes: (1) completion of testing of the 100 keV chopper-buncher system demonstrating a normalized emittance well under the design goal of 2.6 π mm mrad at currents exceeding the design goal of 600 μA; (2) operation of the rf structures comprising the 5 MeV injector linac at power levels up to 50 kW/m, resulting in an accelerating gradient at ß=1 of 2 MV/m (compared to a design goal of 1.5 MV/m). The measured shunt impedance is 82.5 Mn/m; (3) construction and installation of the 30 ton end magnets of the RTM. Field mapping of one magnet has been completed and its uniformity exceeds the design goal of ±2 parts in 104; (4) performance tests (with beam) of prototype rf beam monitors which measure current, relative phase, and beam position in both transverse planes. (5) Installation and initial operation of the primary control system.