Higher twist contributions to the inclusif production of single (RHO) and double (RHO or PION) meson in proton-proton and proton-antiproton collisions

In this thesis, we calculate the contribution of the higher–tivist Feynman diagrams to the large–𝑝𝑇 inclusive single (𝑝 + 𝑝̅→ 𝜌 +(𝜌 −) + 𝛾) and double (𝑝𝑝̅→ 𝜋 +𝜋 −𝑋 and 𝑝𝑝̅→ 𝜌 0𝜌 0𝑋) meson production cross section in hadron–hadron collisions in case of the frozen coupling approaches. The preceding results demonstrate that higher tivist contributions must be considered especially in the region of 𝑝𝑇 < 5𝐺𝑒𝑉/�