Proton Triple Color Stringy Tube Structure in Electron-proton Deeply Virtual Compton Scattering

To solve the issue of single-color stringy proton model on the effective description of the data from the electron-proton deeply virtual Compton scattering at HERA, firstly we assume that the three constituent quarks inspiring three color stringy tubes, then we construct the proton profile function from these color tubes, finally we establish a triple-color stringy proton model in order to improve the topological structure of the single-color stringy proton model. The electron-proton deep virtual Compton scattering amplitudes are calculated, the results show the new topological structure increases the scattering amplitude leading to a better agreement between the triple color stringy proton model and the HERA measurements, which successfully solve the issue of the single-color stringy proton model. Meanwhile, the proton radius resulting from the triple-color stringy proton model is consistent with the one measured by GlueX group at Jefferson National Lab. Furthermore, we extend the triple-color stringy proton model to electron-ion deep virtual Compton scattering and calculate the scattering amplitude. The results show that the triple-color stringy structure plays a remarkable contribution to the amplitude, which indicates that the nucleus also has the information of the triple-color stringy structure. This outcome may play a significant role in the understanding of the spatial structure of a nucleus.