2000 character limit reached
Baryonic resonances close to the Kbar-N threshold: the case of Sigma(1385)^+ in pp collisions (1109.6806v1)
Published 30 Sep 2011 in nucl-ex
Abstract: We present results of an exclusive measurement of the first excited state of the Sigma hyperon, Sigma(1385)+, produced in p+p -> Sigma+ + K+ + n at 3.5 GeV beam energy. The extracted data allow to study in detail the invariant mass distribution of the Sigma(1385)+. The mass distribution is well described by a relativistic Breit-Wigner function with a maximum at m_0 = 1383.2 +- 0.9 MeV/c2 and a width of 40.2 +- 2.1 MeV/c2. The exclusive production cross-section comes out to be 22.27 +- 0.89 +- 1.56 +3.07 -2.10 mu b. Angular distributions of the Sigma(1385)+ in different reference frames are found to be compatible with the hypothesis that 33 % of Sigma(1385)+ result from the decay of an intermediate Delta{++} resonance.