2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/47927We discuss the studies on structure functions at the possible future RCNP facility. At this stage, an electron-proton or proton-proton collider with sqrt{s}=5 - 10 GeV is considered. We explain large-x physics, nuclear modification of sea-quark and gluon distributions, and tensor spin structure function as the interesting topics at the facility. The large-x parton distributions are important for finding new physics beyond QCD in anomalous events such as the CDF jet data. The nuclear parton distributions are valuable in detecting a quark-gluon signature in heavy-ion reactions. The tensor structure function b_1 is a new field of high-energy spin physics. Considering these physics possibilities, we believe that the possible RCNP facility is important for the hadron-structure community.1+10 pages, LATEX2e with epsfig.sty, wrapfig.sty, and amsmath.sty, 5 eps figures. Talk given at the Workshop on Future Plan at RCNP, Osaka, Japan, March 9-10, 1998, to be published in proceedings. Complete postscript file including the figures is available at http://www.cc.saga-u.ac.jp/saga-u/riko/physics/quantum1/structure.html Email: 97sm16@edu.cc.saga-u.ac.jp, kumanos@cc.saga-u.ac.jpHigh Energy Physics - PhenomenologyHigh Energy Physics - ExperimentNuclear Theorytext