Baryonremains

Baryonremains are a concept in high-energy particle physics describing the portion of an initial baryon that remains after a hadronic collision’s hard scattering. They consist of the valence and spectator partons that did not participate in the short-range interaction and thus carry the original baryon number into the final state.

Origin and structure: In proton–proton or heavy-ion collisions, after the parton-level scattering, the remaining quarks and gluons (the beam remnant) must be hadronized. The remnants are typically forward-moving and connect through color strings to the rest of the event, producing forward hadrons and sometimes baryons. Their exact composition depends on the initial hadrons and on which partons were involved in the interaction.

Theoretical treatment and modeling: Event generators simulate baryonremains with a beam-remnant module. Their detailed composition depends on the initial hadrons and on which partons were exchanged. Hadronization models, such as string fragmentation or cluster models, convert remnants into final-state particles and influence the underlying event, including particle correlations and forward-going yields.

Experimental relevance: Baryonremains contribute to particle yields at large rapidities and to baryon-number transport across rapidity gaps. They are studied with forward detectors and analyses of forward baryons, and they affect measurements of diffraction, multiplicity, and underlying-event activity. Understanding baryonremains helps improve the accuracy of collider event modeling and the interpretation of forward-region data.