The Isoscalar Mesons and Exotic States in Light Front Holographic QCD

Understand

In this article a systematic quantitative analysis of the isoscalar bosonic states is performed in the framework of supersymmetric light front holographic QCD.

• It is shown that the spectroscopy of the $\eta$ and $h$ mesons can be well described if one additional mass parameter -- which corresponds to the hard breaking of chiral $U(1)$ symmetry in standard QCD -- is introduced.
• The mass difference of the $\eta$ and $\eta'$ isoscalar mesons is then determined by the strange quark mass content of the $\eta'$.
• The theory also predicts the existence of isoscalar tetraquarks which are bound states of diquarks and anti-diquarks.