Photo-and electro-production of narrow exotic states:From light quarks to charm and up to bottom

Accessing a full image of the inner content of hadrons represents a central endeavour of modern particle physics,with the main scientific motivation to investigate the strong interaction binding the visible matter.On the one hand,the structure of known exotic candidates is a fundamental open issue addressed widely by scientists.On the other hand,looking for new states of exotic nature is a central component for theoretical and experimental efforts from electron-positron machine and electron accelerator with fixed target to heavy ion and electron-ion colliders.In this article we present a succinct short overview of the attempt to search for exotic narrow N∗and Z states containing light quarks only or also charm,and its connotation for bottom regions(the latter two are also known as Pc(Zc)and Pb(Zb)states,respectively in the literature).We address the effort of searching for exotic narrow N∗and Z states in light quark sector.We focus on recent progress in searching for signal of Pc and Zc states photoproduction and its implication into the Pb and Zb photoproduction and their decay properties.We also discuss future perspectives for the field in electron-ion colliders,a good place to disentangle the nature of some of these states and investigate some other enlightening topics including QCD trace anomaly and quarkonium-nucleon scattering length.

Vector meson J/ψ,φ electro-production in QCD

We study the vector meson electro-production off the proton in a QCD inspired model. A calculation of the differential cross section is performed for the J/ψ, Ф meson off the proton. The theoretical results are consistent with the experimental data, and remind us to consider the contribution from the tensor glueball and Odderon to the differential cross section. Since gluons interact among themselves via self-interaction, the gluons can form a glueball with quantum numbers I^G, J^PC = 0^＋, 2^＋＋ with a decay width Гt = 100 MeV and mass of mG = 2.23 GeV. The three gluons can form a three gluon color bound state with charge conjugation quantum number C = -1. This study is quite important to verify the validity of QCD and to search for new particles （tensor glueball and Odderon） as well as quest for new physics.

Damage effect analysis and experiment for electronic equipment in impact vibration environment

This paper analyzes the electronic equipment＇s effect factors such as structure characteristics and environment.The radar equipment is taken as an experimental subject.The damage laws of electro-products in vibration environment are analyzed.The experiment shows that the damage of electro-products in vibration environment has relations with both the type and amplitude of vibration and their structure.

Baryon resonance analysis from SAID

We discuss the analysis of data from πN elastic scattering and single pion photo- and electroproduction. The main focus is a study of low-lying non-strange baryon resonances. Here we concentrate on some difficulties associated with resonance identification, in particular the Roper and higher P11 states.