Search H₁ In Decay Of Heavy Quarkonium & Study ρ-ω Mixing In B→Dππ

There are two parts in this thesis:a, σ - ω mixing in B →Dπ+π-; b, Search h1 in heavy quarkonium.Part one:B~0 →/ψπ+π- had been done in chiral unitary. But there is a difference in peak with the data from LHCb. A isospin violation between I= 0(ω) and I=1(p) may cause the difference in peak. Similarly, there should be a isospin violation in B B→ Dπ+π-. We try to calculate the decay precisely, which includes the isospin violation. Based on the technic used in B~0→ J/ψπ+π-, we get the mass distribution of B decay to Dπ+π-, We use the parameters in B~0→ J/ψπ+π-, which fits the peak in the data from LHCb well.Part two:I calculated some processes based chiral unitary and local hidden gauge. In such progresses, T to ηch1, ηcD*D*, ηb→J/ψD*D*,ψD*D*,ψ(3770)→ ηK*K*, ψ(3686)→ηK*K*, I got the results of three-body decays. There may exist h1 consisted of D*D* and K*K*. Based on my results, labs can design experiments to search h1 and make sure the structure of h1. The details are contrast the data with lines in my calculations. Then, we can get the information of the structure of h1, the interaction is dynamical potential comes from local hidden gauge, constant potential or others. As the calculation expresses the data well, it will be a good news for local hidden gauge, or we can use constant potential to deal with many issues.