A multi-detector array for high energy nuclear e+e- pair spectrosocopy
K.E. Stiebing, F.W.N. de Boer, O. Froehlich, H. Bokemeyer, K.A. Mueller, K. Bethge, J. van Klinken
Abstract
A multi-detector array has been constructed for the simultaneous measurement of energy- and angular correlation of electron-positron pairs produced in internal pair conversion (IPC) of nuclear transitions up to 18 MeV. The response functions of the individual detectors have been measured with mono-energetic beams of electrons. Experimental results obtained with 1.6 MeV protons on targets containing
11
B and
19
F show clear IPC over a wide angular range. A comparison with GEANT simulations demonstrates that angular correlations of
e
+
e
−
pairs of transitions in the energy range between 6 and 18 MeV can be determined with sufficient resolution and efficiency to search for deviations from IPC due to the creation and subsequent decay into
e
+
e
−
of a hypothetical short-lived neutral boson.