In this article, we explain the emittance exchange and partitioning by the phase-space rotation technique and its applications. Because the emittance has a large impact on the accelerator performance, the low emittance beam generation has been an important issue for accelerator science. Although there are many proposals to obtain such low emittance beam employing various state-of-the-art technologies, the phase-space rotation extend our access to new beam parameter region by adding new operability on the beam to the classical approach.

Planned muon to electron conversion search experiment (COMET) needs 8 GeV bunched proton beam with a 1 MHz pulse structure. In this experiment, an intensity ratio of in-between residual beam to main pulsed beam, which is expressed as extinction, should be less than the level of 10⁻¹⁰. In RUN78 (Jan. to Feb., 2018), we have succeeded in slow extraction of 8 GeV protons with 7.3×10¹² ppp, satisfies the COMET phase-I requirement, and the extinction derived from timing measurement of secondary particles generated from the target shows a promising result. A scenario to explain the measured extinction has been proposed.

It is essential to develop the high power EUV light source up to 1 kW to realize the 3 nm node to reduce stochastic variation and achieve higher throughput. To this end, our group has proposed an energy recovery linac (ERL)-based free electron laser (FEL) which will produce more than 10 kW EUV light to provide the light into several scanners. This article describes the present status of the EUV Lithography which is a starting point of HVM, and the future prospect of a high power EUV-FEL light source based on ERL accelerator technologies.

ILC will be a unique facility when it has come. While the main purpose of ILC is concentrated on the high-energy physics for the time being, it should be very useful to consider diversified usage of facility among the wide science fields. In order to reveal variety of ideas towards the diversified applications, workshop “ILC diversified application” was held twice. As results of workshop, we report potential of multilateral use of the ILC.

The Asian Linear Collider Workshop 2018 was held in Fukuoka from May 28 to June 1, 2018. This article briefly reports the workshop, the status of the International Linear Collider (ILC), and then a statement on “Towards the realization of the International Linear Collider,” that was issued during the workshop. The statement expressed (1) physics importance of the 250 GeV ILC, (2) maturity and application of superconducting RF technology, and (3) necessity of a positive message from the Japanese government in a timely manner.

Young Researchers Association of the Japan Beam Physics Club was established in March 2018. We will report a detail history and trigger of the establishment of our association, followed by the explanations of ourselves, which are the structure of our organization, members, activities and purposes. Lastly, we will discuss our future vision of Young Researchers Association of the Japan Beam Physics Club.

SOKENDAI plays the central role in postgraduate education of KEK. The School of High Energy Accelerator Science consists of three departments, Accelerator Science, Material Structure Science, and Particle and Nuclear Physics. Research staff of the Accelerator Laboratory and the Applied Science Laboratory takes charge of the faculty of the Department of Accelerator Science. Students are gathered from variety of universities, technical colleges and companies, and there are many international students from Asian countries. They pursue their graduate research by taking advantage of the environment of KEK, one of the world’s leading institute of accelerator science.

I stayed at Thomas Jefferson National Accelerator Facility as a JSPS Overseas Research Fellow for two years. Here, I describe experiences getting through a two-year stay and give some advices to be selected to a JSPS Overseas Research Fellow.