New lifetime limits on the charge non-conserving (CNC) electron capture with excitation of the 417.9 keV nuclear level in the 127 I are established by using the coincidence technique. The analysed exposure is 0.87 ton × yr, collected deep underground at the Gran Sasso National Laboratory of the INFN by the highly radiopure DAMA/LIBRA setup (≈250 kg of highly radiopure NaI(Tl)). The new limit on the mean life is τ > 1.2 × 10 24 yr (90 % C.L.), about one order of magnitude larger than those

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... usly available for CNC electron capture involving nuclear level excitations of 127 I and of the same order of magnitude than those achieved for analogous processes in 129 Xe.