Seminarium Fizyki Wielkich Energii

Anomalous soft photons in excess of what is expected from electromagnetic bremsstrahlung have been experimentally observed in association with the production of mesons in high-energy hadron-hadron and e+e- collisions. We propose a quantum field theory model for the simultaneous production of mesons and anomalous soft photons in a flux tube to explain the phenomenon[1]. In such a theory, the bosonized QCD2+QED2 system for quarks with two flavors contains QCD2 and QED2 bound states, with an isoscalar photon at about 25 MeV and an isovector (I=1,I3=0) photon at about 44 MeV. Consequently, when a quark and an antiquark at the two ends of a string pull apart from each other at high energies, both hadrons and soft photons will be produced simultaneously in the string fragmentation process, leading to the production of associated soft photons during the meson production process. [1] C. Y. Wong, Phys. Rev. C81, 064903 (2010) [arXiv:1001.1691], and [arXiv:1011.6265].