At the Montreal Tandem accelerator, an experiment is being set up to measure
internal pair creation from the decay of nuclear excited states using a
multiwire proportional chamber and scintillator bars surrounding it from the
DAPHNE experiment. The acceptance covers a solid angle of nearly 4Ï€.
Preamplifiers and the data acquisition hardware have been designed and tested.
The water-cooled 7LiF target, mounted on an Al foil is in a thin carbon
fiber section of the beamline. The experiment will focus at first on a
measurement of the internal pair creation from the 18.15 MeV state of 8Be.
Assuming the ATOMKI evaluation of the electron-pair production rate from X17, a
Geant4 simulation predicts observation of a clear signal after about two weeks
of data taking with a 2 μA proton beam. The IPC measurement could
eventually be extended to the giant dipole resonance of 8Be, as well as to
other nuclei, in particular to 10B.Comment: 5 pages, 4 figures, Proceedings contribution, TRIUMF Ariel Workshop,
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