Electromagnetic Form Factor of Doubly-Strange Hyperon

The standard model of particle physics is a well-tested theoretical framework, but there are still some issues that deserve experimental and theoretical investigation. The Ξ resonances with strangeness S=−2, the so-called doubly-strange hyperon, can provide important information to further test the standard model by studying their electromagnetic form factors, such as probing the limitation of the quark models and spotting unrevealed aspects of the QCD description of the structure of hadron resonances. In this work, we review some recent studies of the electromagnetic form factors on doubly-strange hyperons in pair production from positron–electron annihilation experiment.

Electromagnetic form factor of Ds∗ meson from Nf = 2 twisted mass lattice QCD

We investigate the electromagnetic form factor of [Formula: see text] meson using [Formula: see text] twisted mass lattice quantum chromodynamics gauge configurations. The numerical simulations are carried out under twisted boundary conditions which are helpful to increase the resolution in momentum space. We determine electromagnetic form factors with more small four-momentum transfer, and further fit the charge radius for [Formula: see text] meson.

Baryon Form Factors at BESIII

In this talk I present recent progress on the studies of baryon form factors at BESIII, including the measurements of the time-like proton electromagnetic form factor via e+e−→ pp̅ in the center-mass-system energy region 2.0 −3.08 GeV, as well as the electromagnetic form factors of Λ and Λc, respectively. These results are followed by a short discussion about the prospects of the BESIII program in this area.

The most correct ρ0(770) meson mass and width values

By application of the pion electromagnetic form factor and also the P-wave isovector ππ scattering phase shift parametrizations, following from the first principles, like unitarity and analyticity, for a description of the corresponding accurate data, it is clearly demonstrated that the ρ0(770) meson mass and width values obtained by the Gounaris-Sakurai model in a description of the same data can not be accepted as correct ones.