$K^0_S$ meson production in inelastic p+p interactions at 31, 40 and 80 $\text {Ge}\hspace{-1.00006pt}\text {V}\!/\!c$ beam momentum measured by NA61$/$SHINE at the CERN SPS

The yields of $K^0_S$ mesons have been measured in inelastic p+p interactions at incident projectile momenta of 31, 40 and 80 GeV/c (√s N N = 7.7, 8.8 and 12.3 GeV, respectively). The data were recorded by the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron and the $K^0_S$ mesons identified via their decays into π+π− pairs. Double-differential distributions are presented as function of transverse momentum and rapidity. The mean multiplicities of $K^0_S$ mesons were determined to be (5.95 ± 0.19(stat) ± 0.30(sys)) × 10−2 at 31 GeV/c, (7.61 ± .13(stat) ± 0.43(sys)) × 10−2 at 40 GeV/c and (11.58 ± 0.12(stat) ± 0.55(sys))×10−2 at 80 GeV/c. The results on $K^0_S$ production are compared with the production of charged kaons in corresponding reactions and with model calculations (Epos1.99, SMASH 2.0 and PHSD) as well as with published data from other experiments