Transactions of the Korean Nuclear Society Virtual Autumn Meeting December 17-18 Development of Trigger Control System for Beam Diagnostics at KOMAC Young-Gi Song*, Sung-Yun Cho, Jae-Ha Kim, Jeong-Jeung Dang Korea Multi-purpose Accelerator Complex, Korea Atomic Energy Research Institute, Gyeongju 38180, Korea *Corresponding author:ygsong@kaeri.re.kr 1. Introduction The KOMAC facility consists of low-energy component, including a 50-keV ion source, a low energy beam transport (LEBT), a 3-MeV radio- frequency quadrupole (RFQ), and a 20-MeV drift tube linac (DTL, as well as high-energy components, including seven DTL tanks for the 100-MeV proton beam. The KOMAC has been operating 20-MeV and 100-MeV proton beam lines to provide proton beams for various applications [1]. Each components of the pulsed operation mode has a timing trigger signal with precision synchronization. A timing system for beam extraction and for beam diagnostic components is required to provide precise pulse signals synchronized with a 300-MHz RF reference frequency. The KOMAC timing system was upgraded to a programmable event timing system that is synchronized with the reference signal such as RF and AC main frequency and is being used stably [2]. In the operating state of pulse mode, it is necessary to provide unlimited beam pulses within the RF operation repetition rate. The beam trigger control is implemented by commercial pulse delay generator BNC575 (B Berkeley Nucleonic Corporation) and sequence ram of timing system. The pulse delay generator is synchronized to the clock and trigger generated by the main timing system. In order to provide efficient beam pulses in the future, we plan to apply a control system that can automatically control the functions of beam pulses and beam counters. 2. Beam Pulse Control The timing system was fabricated using a versa module eurocard (VME) system composed of an event generator (EVG-230) and event receiver (EVR-230RF) based on EPICS software. The EVG is responsible for generating and sending out event codes over 2-Gbits/s fiber optic links to an array of EVR, which is programmed to decode specific event codes. The EVR generates trigger pulses for the linac components, such as the beam diagnostics, high-power RF system, and high-voltage power supply through the fan-out board. Fig 1 shows a MRF timing system and a schematic layout of the timing system with a 300-MHz external reference signal is described in Fig 2. Two methods are used to generate beam triggers: The first is to use a pulse generator and the second is to add software to the timing system. Fig 1. MRF timing system EVG EVR and fan-out Fig 2. Schematic layout of the event timing system in the klystron galley and beam experiment hall. 2.1 Pulse Delay Generator for Beam Trigger For beam extraction, timing was added to the beam injector with a BNC565 delay generator. The delay generator receives a 20 MHz clock and trigger signal from the EVR as described in Fig 3. Fig 3. Schematic for providing beam triggers to an injector and beam target rooms using timing system and pulse delay generator. The trigger signal determines the repetition rate for the beam service request, and the delay generator 가속기개발운영부/2020-10-16 14:16