Test of the pauli exclusion principle for atomic electrons and for nucleons

V. M. Novikov and A. A. Pomansky Institute for Nuclear Research, Academy of Sciences of the USSR, Moscow (USSR) D. Miljanic and A. Ljubicic Institute Rudjer Boskovic, Zagreb, Yugoslavia B . A. Logan, Department of Physics, University of Ottawa (Canada) Accelerator mass spectrometry at the Munich accelerator laboratory was used to test the validity of the Pauli exclusion principle (PEP) for atomic electrons and for nucleons. In natural samples, upper limits for the concentrations of anomalous atoms where three elec­ trons are occupying the K shell and of anomalous nuclei with three protons in the nuclear ls1;2 shell thus violating PEP were obtained. In the case of anomalous 20Ne atoms with three electrons in the K shell, a limit of 20Ne/20Ne < 2 · 1 0-21 was measured with a time-of­ flight technique. In the case of anomalous 36Ar atoms, a limit of 36Ar/36Ar < 4 · 10-17 was obtained detecting hydrogenlike Ar ions. For anomalous 5Li nuclei with three protons in the nuclear ls112 shell, a limit of 5Li/Li < 2 · 10-14 was measured with a time-of-flight technique for binding energies of anomalous 5Li between 0 and 40 MeV. 1supported by BMFT