Inclusive hadronic fragmentation in K$^{\pm}$p interactions at 32 GeV/c and counting rules

Longitudinal invariant structure functions E d σ d x for a number oflow p t hadronic fragments produced in K +- interactions at 32 GeV/ c are presented. Data were obtained in the Mirabelle bubble chamber. The fragmentation modes investigated are K ± → K 0 , K̄ 0 , K ∗0,+ (890), K̄ ∗0,− (890), ϕ, ϱ 0 , π +- , Λ, ḡL, and p → p inel , Δ ++ (1236), Λ, ḡL, π ± , K 0 , ϱ 0 . These various fragmentation spectra clearly fall into a definite hierarchy, the invariant cross sections being more suppressed at large | x | the bigger the difference between initial and final state hadron quantum numbers. Invariant cross sections in the fragmentation regions are adequately fitted by a power law Edσ / dx ∝ (1 − | x |) n as suggested by dimensional or Regge counting The values of n are in general consistent with values obtained at FNAL and ISR energies for comparable data. They are in good overall agreement with the quark counting rules as recently reformulated, and the deviations observed suggest corrections due to strange (s) and light (u, d) quark mass differences. The power laws governing the kaon valence quark structure functions behave at large x as s K V ( x ) x →+1 ∼ (1 − x ) 0.5 and ū K V (x) x→+1 ∼ (1 − x) 1.5 .