Development of a 10 K automated sample exchange cryostat for SANS_CSNS

The Small-angle Neutron Spectrometer at China Spallation Neutron Source (SANS_CSNS) is a functional apparatus utilized for the examination of structures and inhomogeneities within the size range of 1 to 100 nm. The development of sample environments for in situ experiments at low temperatures at SANS_CSNS is urgent in order to address the increasing demands of users. The CSNS Sample Environment Group has successfully designed and constructed an automated sample exchange cryostat for SANS experiments, capable of operating in a temperature range of 10 ∼ 500 K. This cryostat has been specifically engineered to accommodate up to four samples simultaneously and exchange samples automatically in order to optimize the utilization of neutron beams by minimizing the downtime associated with manual sample handling. The results of simulation and temperature measurement proved that sample temperature could be accurately controlled from 10 K to 500 K through the incorporation of a 4 K GM cryocooler and a heater. Furthermore, neutron scattering studies conducted on SANS_CSNS proved that this cryostat exhibits commendable temperature control capabilities and minimal background interference. This automated sample exchange cryostat will be available to researchers of SANS_CSNS in the following user programs.