A LIQUID HELIUM CRYOGENIC TARGET FOR SHOCK COMPRESSION EXPERIMENTS

A liquid helium cryogenic target,which has optimized structure,a separated vacuum interval for heat insulation and a stream-cooled shield is introduced.By using continuously flowing liquid helium and an exhausting pump to decrease the back pressure in the liquid helium reservoir,the temperature in the target gas space has reached 4.2 K under an about 100 Pa vacuum environment.The cryogenic target can be used for shock compression experiments of helium and other gas substances.