The experimental system JUSO at the University of Osnabrück (Figure
2.2) is an UHV system with a base pressure in the
low mbar range. Primary ions are extracted from a
plasma ion source and mass analyzed by a 90
sector
field magnet. With an electric deflection system in front of the analyzing
magnet the primary beam can be pulsed to allow time-of-flight (TOF)
measurements. The scattering surface is mounted on a three axis manipulator
equipped with electron beam heating. A thermocouple is used for temperature
control. Downstream from the target, a TOF tube is mounted at a fixed
scattering angle of 10
. Scattered ions are separated
from scattered neutral particles by a postacceleration stage. Two
stacked microsphere plates (MSP) [15] are used as the detector.
The angle aperture for detection is 1.2
. Neutral primary
particles are produced by neutralization of the primary ion beam in
a gas cell, placed between the sector magnet and the target chamber.
March 2001 - Martin Wieser, Physikalisches Institut, University of Berne, Switzerland