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In this paper we report on a systematic search for a neutral boson in themass range between 5 and 15 MeV/c$^{2}$ in the decay of highly excited nuclei.Its signature is found a deviation in the angular correlation of the $e^+e^-$pairs from conventional internal pair conversion (IPC) resulting from of itstwo-body decay kinematics. With an $e^{+}e^{-}$ pair-spectrometer, a number oftransitions has been investigated in the  ${\alpha}$--nuclei $^{8}$Be, $^{12}$C and $^{16}$O, following light ioninduced reactions at low bombarding energies, first at IKF in Frankfurt andduring the last years at ATOMKI in Debrecen. Startlingly, in all isoscalartransitions excess $e^{+}e^{-}$ pairs are found at large angles with branchingratios with respect to the total yield ranging from 10$^{-2}$ to 10$^{-6}$. Ifthese deviations are all related to the two-body decay of an $X$-boson, thisobservation implies plural $X$-bosons. An analysis of all angular spectra witha boson search program, yields a pandemonium of more than ten candidate bosons.Comment: 7 pages, 2 figures, contributed paper to the Int. Symposium on Exotic  Nuclear Systems (ENS05), ATOMKI, Debrecen, Hungary, 20-25 June 200

Anomalous Internal Pair Conversion Signaling Elusive Light Neutral Particles