Cryogenic sample environments shared at the MLF,J-PARC

Abstract

We present the status of the low-temperature devices shared by several neutron instruments of the Materials and Life Science Experimental Facility (MLF), J-PARC. In recent years, the Cryogenics and Magnets group of the Sample Environment (SE) team has introduced three cryostats at the MLF: a top-loading ⁴He cryostat, a bottom-loading ³He cryostat, and a ³He–⁴He dilution refrigerator insert. The group also manages a superconducting magnet which entered into service in 2012. Progress has been made with these SE, including the development of a new system for controlling the ³He cryostat and an oscillating radial collimator for using efficiently the superconducting magnet. These innovations have significantly increased the frequency with which these cryostats and magnet are used. During the last Japanese fiscal year, some of them were used approximately half of the total number of days of beam operation.