Further study of narrow baryon resonance decaying into $K^0_s p$ in $pA$-interactions at $70 GeV/c$ with SVD-2 setup

Abstract

The inclusive reaction $p A \to pK^0_s + X$ was studied at IHEP accelerator with $70 GeV$ proton beam using SVD-2 detector. Two different samples of $K^0_s$, statistically independent and belonging to different phase space regions were used in the analyses and a narrow baryon resonance with the mass $M=1523\pm 2(stat.)\pm 3(syst.) MeV/c^2$ was observed in both samples of the data. The statistical significance was estimated to be of $8.0 \sigma$ (392 signal over 1990 background events). Using the part of events reconstructed with better accuracy the width of resonance was estimated to be $\Gamma < 14 MeV/c^2$ at 95% C.L.