TEST OF THE PAULI EXCLUSION-PRINCIPLE FOR NUCLEONS AND ATOMIC ELECTRONS BY ACCELERATOR MASS-SPECTROMETRY

The Pauli exclusion principle was tested by searching with accelerator mass spectrometry for non-Paulian atoms with three electrons in the K-shell and for non-Paulian nuclei with three protons or three neutrons in the nuclear 1s1/2 shell. For non-Paulian atoms of Ne-20 and Ar-36 the following limits have been obtained: N(Ne-20)/N(Ne-20) < 2.10(-21) and N(Ar-36)/N(Ar-36) < 4.10(-17). For non-Paulian nuclei of Li-5 and He-5 with three protons or three neutrons, respectively, in the nuclear 1 s1/2 shell the following limits have been measured: N(Li-5)/N(Li-6) < 0.8.10(-17) for a range of proton separation energies of Li-5 between 0 and 50 MeV and N(He-5)/N(He-4) < 2.10(-15) for neutron separation energies between 0 and 32 MeV. The result for Li-5 is used to deduce a limit for the probability beta-2/2 of finding two colliding protons in the symmetric state with respect to exchange to be beta-2/2 < 0.5.10(-32).