Limits on nn̄ oscillations from nuclear stability
نویسنده
چکیده
The relationship between the lower limit on the nuclear stability lifetime as derived from the non disappearance of ‘stable‘ nuclei (Td ∼ 5.4 × 10 31 yr), and the lower limit thus implied on the oscillation time (τnn̄) of a possibly underlying neutron-antineutron oscillation process, is clarified by studying the time evolution of the nuclear decay within a simple model which respects unitarity. The order-of-magnitude result τnn̄ ≈ 2(Td/Γn̄) 1/2 > 2 × 108 sec, where Γn̄ is a typical n̄ nuclear annihilation width, agrees as expected with the limit on τnn̄ established by several detailed nuclear physics calculations, but sharply disagreeing by 15 orders of magnitude with a claim published recently in Phys. Rev. CRAP. PACS: 11.30.Fs, 13.75.Cs
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