Diquark state of a_0 (980) meson and its decay width calculation in covariant quark model
Keywords:
diquark, covariant quark model, scalar meson, decay width, tetraquarkAbstract
In paper we study the quark structure and mechanism of the formation of a а0(980) meson’s bound state. Recently, the quark structure of the scalar meson а0(980) arouses great interest. Therefore, in our work we calculated the width of radiative decays for diquark states of а0(980) meson at different values of meson’s size in the covariant quark model, which is the effective quantum field approach to hadron interactions based on lagrangian interaction of hadrons with their constituent quarks. In this model there are no threshold singularity corresponding to the birth of the quarks due to introducing the infrared cutoff in the space of Fock-Schwinger parameters. The model has several free parameters: the mass of constituent quarks, the infrared cutoff parameter and the parameter that describe effective size of hadrons.The results obtained differ from the experimental data on the order. Thus assume that а0(980) meson is tetraquark system.
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