Magnetic and quadrupole moments of the Zc(3900)

Abstract

The electromagnetic properties of the tetraquark state Zc(3900) are investigated in the diquarkantidiquark picture and its magnetic and quadrupole moments are extracted. To this end, the light-cone QCD sum rule in electromagnetic background field is used. The magnetic and quadrupole moments encode the spatial distributions of the charge and magnetization in the particle. The result obtained for the magnetic moment is quite large and can be measured in future experiments. We obtain a nonzero but small value for the quadrupole moment of Zc(3900) indicating a nonspherical charge distribution.

The magnetic moment of the $$Z_c(3900)$$ Z c ( 3900 ) as an axialvector tetraquark state with QCD sum rules

“…[25], Ozdem and Azizi obtain the magnetic moment μ Z = 0.67 ± 0.32 μ N from the light-cone QCD sum rules, where the μ Z decreases monotonously with increase of the Borel parameter, the Borel window is not flat enough. Compared to the QCD sum rules in the external electromagnetic field, the light-cone QCD sum rules have more parameters with limited precision.…”

“…So it is interesting to study the interaction of the Z c (3900) with the photon, which plays an important role in understanding its nature. In fact, the works on the magnetic moments of the exotic particles X , Y , Z are few, only the magnetic moments of the Z c (3900), X (5568) and Z b (10610) are studied with the light-cone QCD sum rules [25][26][27].…”

“…As far as the Z c (3900) is concerned, the mass and decay width of the Z c (3900) have been studied with the QCD sum rules in details [10,11,18,19,23,24], while the magnetic moment of the a e-mail: zgwang@aliyun.com Z c (3900) is only studied with the light-cone QCD sum rules [25]. The magnetic moment of the Z c (3900) is a fundamental parameter as its mass and width, which also has copious information about the underlying quark structure, can be used to distinguish the preferred configuration from various theoretical models and deepen our understanding of the underlying dynamics.…”

The electromagnetic multipole moments of the charged open-flavor ${Z}_{\bar{c}q}$ states

“…There are many studies in the literature devoted to the investigation of the electromagnetic multipole moments of the standard hadrons, but unfortunately relatively little are known the electromagnetic multipole moments of the exotic hadrons. There are a few studies in the literature where the magnetic dipole and quadrupole moments of the exotic states are studied: see [27][28][29] for tetraquarks and [30][31][32][33][34][35] for pentaquarks. More detailed analyses are needed in order to get useful knowledge on the charge distribution, electromagnetic multipole moments and geometric shapes of the non-conventional hadrons.…”

The electromagnetic multipole moments of the possible charm-strange pentaquarks in light-cone QCD

“…There exist a lot of studies in the literature in which the electromagnetic properties of conventional hadrons are studied and electromagnetic multipole moments are obtained, but unluckily our knowledge on the electromagnetic multipole moments of the non-conventional hadrons are very limited. There exist only few studies in the literature devoted to the study of the electromagnetic multipole moments of the exotic states [21][22][23][24][25][26][27][28][29][30][31][32][33][34]. Theoretical works can play important roles in this respect since direct experimental information about the electromagnetic multipole moments of exotic particles is very limited.…”