Article

# Invariant-mass distributions for the pp $\rightarrow$ pp $\eta$ reaction at Q = 10 MeV

European Physical Journal A (Impact Factor: 2.04). 01/2010; DOI:10.1140/epja/i2009-10900-9
Source: arXiv

ABSTRACT Proton-proton and proton- $\eta$ invariant-mass distributions and the total cross-section for the pp $\rightarrow$ pp $\eta$ reaction have been determined near the threshold at an excess energy of Q = 10 MeV. The experiment has been conducted using the COSY-11 detector setup and the cooler synchrotron COSY. The determined invariant-mass spectra reveal significant enhancements in the region of low proton-proton relative momenta, similarly as observed previously at higher excess energies of Q = 15.5 MeV and Q = 40 MeV.

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