The χ~2Fitting About Depressed Hadron Spectrum In Nuclear-nuclear Collision At RHIC Energy Level

The most effective method to find the quark-gluon plasma (QGP) is extreme rela-tivistic heavy ion collisions,The "relativistic Heavy Ion Collider" builted by Brookhaven national laboratory (2000) and the European Large Hadron Collider (2008) provides an unprecedented experiment conditions for studying QGP,and accumulated a Large number of experimental evidence that can prove the QGP matter produced,we study the jet quenching phenomenon appeared at large horizontal momentum region.In the PQCD parton model,we makes the scattering cross section a convolution of three parts:parton distribution functions%harf differential scattering cross section%parton fragmentation functions.But due to the shadowing-effect of the initial state and the jet-quenching phenomenon of the final state,we should correction the parton dis-tribution functions and parton fragmentation functions.In our ZOWW theoretical model. We will express the parton fragmentation function as a formula that in-clude the parton mean free path and the initial time jet transport parameters of the QGP phase center,so the correction factor we calculated is also associated with these two parameters. In order to quantitative represent the fitting degree between theoretical calculation value and experimental observations, we adopt the χ2fitting method.Finally we obtain the χ2value figure as λo and qo,to find the λo and qo which best agreement with the experimental results.In order to explain the results we ana-lyzed the expression of the correction parton fragmentation functions and calculating proportion for each part, hadron spectrum depress caused by the jet quenching in RHIC energy region are analyzed and studied.