Analysis of the hidden-charm pentaquark states based on magnetic moment and transition magnetic moment
Fei Guo, Hao-Song Li
Abstract
Abstract In this work, we calculate the magnetic moments of the $$P^{N^{0}}_{\psi }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>P</mml:mi> <mml:mi>ψ</mml:mi> <mml:msup> <mml:mi>N</mml:mi> <mml:mn>0</mml:mn> </mml:msup> </mml:msubsup> </mml:math> states and $$P^{\Delta ^{0}}_{\psi }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>P</mml:mi> <mml:mi>ψ</mml:mi> <mml:msup> <mml:mi>Δ</mml:mi> <mml:mn>0</mml:mn> </mml:msup> </mml:msubsup> </mml:math> states with valence quark content $${\bar{c}}cudd $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mover> <mml:mrow> <mml:mi>c</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>¯</mml:mo> </mml:mrow> </mml:mover> <mml:mi>c</mml:mi> <mml:mi>u</mml:mi> <mml:mi>d</mml:mi> <mml:mi>d</mml:mi> </mml:mrow> </mml:math> in molecular model, diquark–diquark–antiquark model and diquark–triquark model, as well as the transition magnetic moments in the molecular model. At the same time, we also calculate magnetic moments and transition magnetic moments of $$P^{\Delta ^{++}}_{\psi }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>P</mml:mi> <mml:mi>ψ</mml:mi> <mml:msup> <mml:mi>Δ</mml:mi> <mml:mrow> <mml:mo>+</mml:mo> <mml:mo>+</mml:mo> </mml:mrow> </mml:msup> </mml:msubsup> </mml:math> states and $$P^{\Delta ^{-}}_{\psi }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>P</mml:mi> <mml:mi>ψ</mml:mi> <mml:msup> <mml:mi>Δ</mml:mi> <mml:mo>-</mml:mo> </mml:msup> </mml:msubsup> </mml:math> states in the molecular model as additional products. Our results show that in the diquark–diquark–antiquark model, the magnetic moments of $$ \lambda $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>λ</mml:mi> </mml:math> excitation state are usually larger than the magnetic moments of $$ \rho $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>ρ</mml:mi> </mml:math> excitation state. We find some interesting proportional relationships between the expressions of transition magnetic moments. The results provide important insights for future experimental observation of hidden-charm pentaquark states and help to distinguish their inner structures. With these efforts, our understanding of the properties for the hidden-charm pentaquark states will become more abundant.