We are constructing an isochronous storage ring named “Rare-RI Ring (R3)” at RIKEN RI Beam Factory. R3 is the most favorable equipment for measuring the mass of rare-RIs in a precision of the order of ppm by using the relative TOF measurement method. Recently, we carried out a commissioning run using ⁷⁸Kr beam and the basic performances of R3 were verified. In this article, we describe the history of the past, the results of the commissioning run, and future prospects.

We have developed portable X-band (9.3 GHz) 950 keV/3.95 MeV linac X-ray sources. We are applying the 950 keV system for nondestructive testing testing of industrial and societal infrastructures such as reaction tower, pier and bridge (thinner than 400 mm). Not only the inner structure, but also dynamic image of the inner fluid can be obtained. We have joined the benchmark test for cut samples of a real bridge with other NDT methods hosted by National Institute of Land and Infrastructure Management. We have successfully performed 3.95 MeV electron linac X-ray inspection of bridge sample at Public Works Research Institute for the first time in Japan. We use flat-panel X-ray camera, imaging plate, partial angle CT and Tomosynthesis so that iron-wires of 7 mm diameter can be reconstructed with 1 mm spatial resolution.