Summary
A factor contributing to the apparent binding-energy difference between7HeΛ and7BeΛ is the possibility of the existence of an isomeric state for7HeΛ. A shell-model calculation has been performed for theE2, decay rate from this conjectured state and the results suggest a lower limit of 10−9 s for the lifetime. Comparison with estimates of the A decay lifetime for7HeΛ adds weight to the existence of the isomeric state.
Riassunto
Un fattore che contribuisce all’apparente differenza deU’energia di legame fra7Heλ e7BeΛ `e la possibile esistenza di uno stato isomerico del7Heλ. Si è effettuato, in base al modello a strati, un calcolo del rapporto di decadimentoE2 da questo ipotetico stato ed i risultati suggeriscono per la vita media un limite inferiore di 10−9s. Il confronto con le valutazioni del periodo medio del decadimento Λ del7HeΛ dà peso all’ipotesi dell’esistenza di questo stato isomerico.
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Law, J. The hyperfragment7HeΛ. Nuovo Cim 38, 807–816 (1965). https://doi.org/10.1007/BF02748599
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DOI: https://doi.org/10.1007/BF02748599