COMMISSIONING AND TUNING OF THE NEW BUNCHER SYSTEM IN THE 870 KEV INJECTION BEAMLINE

During the shutdown period 2006 the buncher system in the 870 keV injection line of PSI Injector 2 has been modified. The new buncher configuration consists of a 50 MHz main buncher followed by a low amplitude 150 MHz debunching stage. The motivation for the alternation is outlined. Results of the commissioning and first high intensity beam tests are reported. MOTIVATION Since 2003 PSI's high power proton accelerator facility undergoes an upgrade project with the ambitious goal to enhance the beam intensity from 1.9 mA nowadays towards 3 mA (1,2). Part of this upgrade programme is the modification of the bunching devices in the 870 keV beamline, performed during the shutdown period 2006. The new buncher configuration consists of a 50 MHz main buncher followed by a low amplitude 150 MHz debunching stage. This allows to enhance the beam intensity accelerated with Injector 2 to the desired level without increasing the proton current produced at the ion source.