The gas filled spectrograph increases the efficienc for detecting low yield ERs at near barrier energies. The technique is particularly useful for reactions using low intensity radioactive ion beams. The layout of gas filled split-pole spectrograph is shown below.
A mylar window of 0.94 micron is installed at the entrance of the spectrograph to separate the pressure in the target chamber and the magnet chamber. The focal plane detector consists of a position sensitive avalanche counter (PSAC) and a plastic scintillator. The detector provides position, timing and energy signals.