Speaker
Description
The production of $K$ mesons in $pp$ and $AA$ collisions at high energies is analyzed. We show that the ratio $R_K~=~\frac{\sigma_{K^+}+\sigma_{K^-}}{2\sigma_{K^0_S}}$ calculated within the similarity approach [1] and using the Lund model in the form of MC generator PYTHIA [2] is above 1 even at the conservation of the isospin-symmetry. It is about 1.18 at $\sqrt{s}=$11.9 GeV (the NA61/SHINE data [3]) and it decreases up to 1, when the energy increases up to a few TeV (ALICE data). The reason of this is related to the dynamics of the kaon production. This energy dependence of $R_K$ practically does not depend on the sort of beam or target.
Our calculations do not contradict to the world data at $\sqrt{s}=$ 6-40 GeV and $\sqrt{s}=$ 3 TeV. In the energy region 40 GeV $<\sqrt{s}<$ 200 GeV there is an excess of the STAR data, having too large error bars, over our calculations. Therefore, it is desirable to check the isospin-symmetry violation by improving the measurement accuracy.
References
[1] G.I. Lykasov, A.I. Malakhov, A.A. Zaitsev, Eur.Phys.J.A 60, 239 (2024).
[2] T. Sjoestrand, Comp. Phys. Commun, 82, 4 (1994).
[3] The NA61/SHINE Collaboration, F. Giacosa, M. Gorenstein,R. Poberezhniuk,S. Samanta, Nature Communications, 16, 2849 (2025). arXiv:2312.06572v6 [nucl-ex].
