6533b857fe1ef96bd12b4e12

RESEARCH PRODUCT

Weak decay ofΛc+for the study ofΛ(1405)andΛ(1670)

subject

description

We study the ${\mathrm{\ensuremath{\Lambda}}}_{c}$ decay process to ${\ensuremath{\pi}}^{+}$ and the meson-baryon final state for the analysis of $\mathrm{\ensuremath{\Lambda}}$ resonances. Considering the Cabibbo-Kobayashi-Maskawa matrix, color suppression, diquark correlation, and the kinematical condition, we show that the final meson-baryon state should be in a pure $I=0$ combination, when the meson-baryon invariant mass is small. Because the $I=1$ contamination usually makes it difficult to analyze $\mathrm{\ensuremath{\Lambda}}$ resonances directly from experiments, the ${\mathrm{\ensuremath{\Lambda}}}_{c}$ decay is an ideal process to study $\mathrm{\ensuremath{\Lambda}}$ resonances. Calculating the final-state interaction by chiral unitary approaches, we find that the $\ensuremath{\pi}\mathrm{\ensuremath{\Sigma}}$ invariant mass distributions have the same peak structure in the all charge combination of the $\ensuremath{\pi}\mathrm{\ensuremath{\Sigma}}$ states related to the higher pole of the two poles of the $\mathrm{\ensuremath{\Lambda}}(1405)$. Furthermore, we obtain a clear $\mathrm{\ensuremath{\Lambda}}(1670)$ peak structure in the $\overline{K}N$ and $\ensuremath{\eta}\mathrm{\ensuremath{\Lambda}}$ spectra.