Search for a narrow baryonic state decaying to pKS0 and p‾KS0 in deep inelastic scattering at HERA

Abstract A search for a narrow baryonic state in the p K S 0 and p ‾ K S 0 systemhas been performed in ep collisions at HERAwith the ZEUS detector using an integrated luminosity of 358 pb − 1 taken in 2003–2007. The search was performed with deep inelastic scatteringevents at an ep centre-of-mass energy of 318 GeV for exchanged photon virtuality, Q 2 , between 20 and 100 GeV 2 . Contrary to evidence presented for such a state around 1.52 GeV in a previous ZEUS analysis using a sample of 121 pb − 1 taken in 1996–2000, no resonance peak was found in the p ( p ‾ ) K S 0 invariant- mass distributionin the range 1.45–1.7 GeV. Upper limits on the production cross section are set.