The DAQ system of a new biomacromolecular single-crystal neutron time-of-flight diffractometer in J-PARC/MLF

Tomoyori, Katsuaki; Kurihara, Kazuo; Tamada, Taro; Kuroki, Ryota

A new diffractometer data acquisition system will be designed to adopt the distributed structure in DAQ and storage servers. The DAQ system primarily consists of a number of distributed DAQ nodes, storage servers, and of multiple clients that can retrieve and display histogram images on diffraction image viewing software. The index database that manage all distributed data location mediates between storage server (or archiving) and the multiple clients. We will introduce "DAQ-Middleware", which is the standard DAQ software in J-PARC/MLF. The dynamic device control software can concurrently control the neutron optics and sample environment devices as well as the DAQ in the instrument. The instrument control software framework called "IROHA" integrates the DAQ and device control. The compliant software regarding TOF single-crystal neutron diffraction measurements must provide a predictable user interface and functionality sufficient to review diffraction histogram data for the purpose of decision-making by ordering experimenter. Besides these functions, not only the real time (RT) display for monitoring the status of diffraction experiments but also the RT analysis including data corrections as well as peak searching, cell determination, indexing and integration functionality would be considered to be indispensable especially in order to confirm the validity of measurements.