HIGH-PRESSURE MU-SR STUDIES

The high pressure muSR spectrometer [1] formerly located at CERN has b een transferred to the muE1-beamline at PSI and put back into operatio n with only minor modifications. The essential features of the high pr essure apparatus are described below. The instrument covers a pressure range up to 0.7 GPa which can be extended to 1.4 GPa depending on the design of the high pressure cell. First measurements at PSI were succ essfully carried out with a single crystalline sample of Gd metal. New developments in high pressure cell design are presented. They are exp ected to further improve the signal/background ratio and to extend the pressure range to 1 GPa. One type of cell will allow temperatures abo ve 380 K.