ENHANCED PRODUCTION OF EVENTS AT LARGE-X AND Q(2) AT HERA AND THE MESON CLOUD IN THE NUCLEON

We examine to which degree the effect of the inclusion of target mass corrections in the description at low-Q(2) DIS and meson cloud effects may, after QCD evolution, modify DIS cross section at large x and Q(2 ). This is of interest in the context of recently reported excess of e vents observed by H1 and ZEUS collaborations at HERA. We predict an en hanced production of events at large-x in comparison to standard sets of quark distributions with rather mild Q(2)-dependence. Our analysis leaves some room for more exotic effects beyond parton approach and/or Standard Model. Our large-x effects can be verified in the future whe n the HERA luminosity will be increased. (C) 1997 Elsevier Science B.V .