Status of the 1.76 MeV Pulsed Light Ion Beamline at the Northrop Grumman Advanced Technology and Development Center

The Northrop Grumman Corporation (NGC) Advanced Technology and Development Center (ATDC) beamline has recently been upgraded to provide a 1.76 MeV beam for use in the testing of various types of targets for gamma ray production. The beam is produced by an RF Driven multicusp volume ion source. After transport through a dual solenoid LEBT, the beam is captured and accelerated to 1.013 MeV by an electroformed monolithic RFQ. The DTL boosts the 1.013 MeV output of the RFQ up to 1.76 MeV. A bunching cavity and three permanent magnet quadrupoles match the RFQ output to the DTL. Downstream of the DTL an electromagnetic quadrupole HEBT transports the beam to a diagnostic station housing target testing hardware. Automatic startup and control algorithms have been developed to simplify beamline operations. A new sequenced autostart has been developed to start up all three RF cavities and initiate amplitude, phase, and frequency control subsystems. The frequency-control system, which uses a sliding-short tuner and an I&Q tune sensor, is currently integrated into the main control system. This paper will discuss the status of the beamline with emphasis on the energy upgrade, automatic startup and control systems, and the frequency-control subsystem. Current Beamline Configuration The current beamline configuration is shown in Fig. 1. The beam is produced in a Berkeley type multicusp volume ion source. The source is 7 cm in diameter and the plasma is driven by up to 20 kW of 2 MHz RF. The amplifier is located at ground and is isolated from the HV at the source body and antenna by an integrated RF matching circuit and isolation transformer. Beam is extracted at 36.5 keV using a triode extraction electrode geometry for a final source beam energy of 32 keV. The LEBT consists of a pair of water cooled pancake coil solenoids and a pair of x-y steering magnets. The solenoids are capable of peak fields of about 5000 Gauss in the center (limited by the power supplies), and the steerers of 160 Gauss at 10 Amps. In the middle of the LEBT is a diagnostic station. A variety of diagnostics can be housed in the station including a Faraday cup, quartz plate viewscreen, emittance scanner and others. After the LEBT, an RFQ accelerates the beam to 1.013 MeV in about 1 meter. The RFQ is a twin to the BEAR (Beam Experiment Aboard Rocket) RFQ built for and flown Solenoid Focusing Magnets X-Y Steering Magnets Cryopump Beam Direction Ion Source RFQ Cavity Matching Section Cavity DTL Cavity EM Quadrapole Focusing Magnets