DAMA/LIBRA results on possible Pauli-exclusion-principle (PEP) violating processes (full text)

2009 - A new search for processes normally forbidden by the Pauli exclusion principle has been carried out in 23Na and 127I:

  • a new upper limit on the unit time probability of non-paulian emission of protons with energy Ep>10 MeV has been obtained to be:
    1.63 x 10-33 s-1 (90% C.L.).

    The corresponding limit on the relative strength (δ2) is: δ2 < (3 - 4) x 10-55 (90% C.L.).

  • PEP violating electron transitions in Iodine atoms have also been investigated.
    Lifetimes shorter than 4.7 x 1030 s are excluded at 90%C.L.; the derived limit on the relative strength is:
    δ2e < 1.28 x 10-47 (90% C.L.).

  • This latter limit can also be related to a possible finite size of the electron in composite models of quarks and leptons providing superficial violation of the PEP; the obtained upper limit on the electron size is:
    r0 > 5.7 x 10-18 cm
    (energy scale of E > 3.5 TeV).

    Further future devoted data taking is foreseen.