Enhanced production of charged over neutral kaons in Ar+Sc collisions measured by NA61/SHINE at CERN SPS
Abstract
The isospin symmetry, originating from similar masses of u and d quarks, if exact, would result in equal numbers of charged ( K + and K − ) and neutral ( K 0 and K 0 ) mesons produced in collisions of isospin-symmetric atomic nuclei. The charged and neutral K meson production in Ar+Sc collisions at a center-of-mass energy of 11.9 GeV per nucleon pair was measured by the NA61/SHINE Collaboration. The production of charged K mesons at mid-rapidity is (18.4 ± 6.1)% higher than that of the neutral K mesons. The models of hadron production, including known isospin-symmetry breaking effects, cannot explain the measurements.
Fields of Study & Subjects
High-Energy Particle Collisions Research
Particle physics theoretical and experimental studies
Quantum Chromodynamics and Particle Interactions
Publication details
- Journal / source
- EPJ Web of Conferences
- Publisher
- EDP Sciences
- Volume
- 378
- Pages
- 03001–03001
- Publication date
- 1 January 2026
- Language
- EN