Momenta spectra of protons emitted following the capture of K − in 6Li and 12C have been measured with 1% resolution. The 12C spectrum is smooth whereas for 6Li a well defined peak appears at about 500 MeV/c. The first observation of a structure in this region was identified as a strange tribaryon or, possibly, a ¯K -nuclear state. The peak is correlated with a π − coming from Σ − decay in flight, selected by setting the π momentum larger than 275 MeV/c. The Σ − could be produced, together with a 500 MeV/c proton, by the capture of a K − in a deuteron-cluster substructure of the 6Li nucleus. The capture rate for such a reaction is (1.62± 0.23stat +0.71 −0.44(sys))%/K − stop, in agreement with the existing observations on 4He targets and with the hypothesis that the 6Li nucleus can be interpreted as a (d +α) cluster.
A study of the proton spectra following the capture of K- in Li-6 and C-12 with FINUDA RID G-4236-2010
FIORE, Enrichetta Maria;
2006-01-01
Abstract
Momenta spectra of protons emitted following the capture of K − in 6Li and 12C have been measured with 1% resolution. The 12C spectrum is smooth whereas for 6Li a well defined peak appears at about 500 MeV/c. The first observation of a structure in this region was identified as a strange tribaryon or, possibly, a ¯K -nuclear state. The peak is correlated with a π − coming from Σ − decay in flight, selected by setting the π momentum larger than 275 MeV/c. The Σ − could be produced, together with a 500 MeV/c proton, by the capture of a K − in a deuteron-cluster substructure of the 6Li nucleus. The capture rate for such a reaction is (1.62± 0.23stat +0.71 −0.44(sys))%/K − stop, in agreement with the existing observations on 4He targets and with the hypothesis that the 6Li nucleus can be interpreted as a (d +α) cluster.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
