Speaker
Description
The tensor form factors of the nucleon provide essential information
for understanding its internal spin structure. The monopole tensor
form factor at $Q^2=0$ is identified as the nucleon tensor charge,
which corresponds to the first moment of the leading-twist transverse
parton distribution function $h_1(x)$. While transversity has been
extensively studied both theoretically and experimentally, other
tensor form factors have received much less attention. In this talk,
we present recent results for the nucleon multipole tensor form
factors calculated within the framework of the chiral quark-soliton
model. The framework is based on the effective dynamics arising from
spontaneous chiral symmetry breaking and the mean-field description of
the nucleon at leading order in the large-$N_c$ limit. We find that
the tensor charge ($g_{T}^{u-d}=0.99$) and the tensor anomalous
magnetic moment ($\kappa_{T}^{u+d}=7.61$) are dominated by valence
quark contributions, whereas the tensor quadrupole moment
($Q_{T}^{u-d}=-7.02$) receives a significant contribution from the sea
quarks. We also explore the dependence of these moments on the soliton
size and the pion mass, and find the tensor nature of the nucleon are
fully relativistic. The results are in good agreement with available
lattice QCD data and provide predictions for unmeasured
quantities.
