Evidence for aΛπ+Resonance at 1480 MeV

An enhancement in the $\Lambda {\pi }^{+}$ mass spectrum has been observed at 1480 MeV in the reaction ${\pi }^{+}p\to K^{+}{\pi }^{+}\Lambda$ at 1.7 GeV/c. In addition, the $\Lambda$ polarization undergoes a sharp oscillation in the same $\Lambda \pi$ mass region. The best fit values for this resonance are $M=1480\mathrm{}\pm 15$ MeV and $\Gamma =35\mathrm{}\pm 20$ MeV.