Development of a Vertical Slow Positron Beamline at AIST

A new slow positron beamline with two measurement ports has been installed at AIST. Positrons are generated using the 70 MeV AIST LINAC and are guided to the measurement ports using a solenoid magnetic field. Both beam ports are arranged vertically with the positron beam incident on the sample from above and samples loaded horizontally. Port No. 1 is designed for positron annihilation lifetime spectroscopy (PALS) and Doppler broadening of annihilation radiation (DBAR) measurements with a ∼10 mm diameter positron beam. The beamline on port No. 2 contains a transmission type remoderator for a brightness enhanced positron microbeam, similar to the existing positron probe microanalyzer (PPMA) at AIST.