GAMS
Detectors
Ionization
chamber
Time-of-flight
detectors
Ionization
chamber
At the magnets exit the ions are detected
by a Frisch-grid ionization chamber. It's anode is divided into five section
in order to determine the specific energy loss dE/dx of the ions. An independent
signal for the total energy is taken from the grid which is coupled capacitively
to the cathode. The first and third of the energy loss sections are split
diagonally to determine the position and the horizontal angle of the ions.
The vertical angle is obtained from the time difference of the dE2
and dE4 signal. In order to achieve an homogeneous field potential
rings are placed aroud the detector (including entrance foil).
Time-of-flight
detectors
The TOF consists of two channel-plates
which detect the electrons eliberated from a thin carbon foil. Due to the
high enery achievable at a MP tandem the scattering in the foils is very
low. This allows a 3.5 m TOF path without any beam optical elements. The
achieved time resolution is at about 300 ps, corresponding to a mass resolution
of 1/500 at A=60.
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