The αdecay path of the Hoyle state in 12C (Ex = 7:654MeV) represents one ofthe most challenging questions of modern nuclear physics. Its knowledge can help in theunderstanding of cluster configurations in light nuclei and the possible existence of Bose-Einstein condensates in nuclei. In stars, it is involved in the so-called 3αprocess, wherethe 12C nucleosynthesis occurs. We studied the 14N(d; α2)12C(7:654) reaction at 10:5MeVincident energy to probe its direct decay component. We found, with a precision higherof a factor 5 than any other previous experiment, an almost total absence of direct decaysby-passing the ground state of 8Be. From our analysis, a new upper limit of such decayis found at 0:043% (95% C.L.). Astrophysical 3α process reaction rate calculations haveto be accordingly revised.
The α-decay of the Hoyle state in 12C: A new high-precision investigation / Dell'Aquila, D.; Lombardo, I.; Verde, Giuseppa; Vigilante, M.; Acosta, L.; Agodi, C.; Cappuzzello, F.; Carbone, D.; Cavallaro, M.; Cherubini, S.; Cvetinovic, A.; D'Agata, G.; Francalanza, L.; Guardo, G. L.; Gulino, M.; Indelicato, I.; La Cognata, M.; Lamia, L.; Ordine, A.; Pizzone, R. G.; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S.; Santagati, G.; Spartà, R.; Spadaccini, G.; Spitaleri, C.; Tumino, A.. - 184:(2018), pp. 1-8. (Intervento presentato al convegno 9th European Summer School on Experimental Nuclear Astrophysics, ENNAS 2017 tenutosi a Catania, ITALY nel SEP 17-24, 2017) [10.1051/epjconf/201818401005].
The α-decay of the Hoyle state in 12C: A new high-precision investigation
Dell'Aquila, D.
;
2018-01-01
Abstract
The αdecay path of the Hoyle state in 12C (Ex = 7:654MeV) represents one ofthe most challenging questions of modern nuclear physics. Its knowledge can help in theunderstanding of cluster configurations in light nuclei and the possible existence of Bose-Einstein condensates in nuclei. In stars, it is involved in the so-called 3αprocess, wherethe 12C nucleosynthesis occurs. We studied the 14N(d; α2)12C(7:654) reaction at 10:5MeVincident energy to probe its direct decay component. We found, with a precision higherof a factor 5 than any other previous experiment, an almost total absence of direct decaysby-passing the ground state of 8Be. From our analysis, a new upper limit of such decayis found at 0:043% (95% C.L.). Astrophysical 3α process reaction rate calculations haveto be accordingly revised.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
