Research Of The Law Of Quark Combination In High Energy Collisions

The production of hadrons in high energy collisions always involves processes of hadronization, which means the formation of hadrons from the produced quarks and gluons in these collisions. This process is very important for researching of the quark-gluon plasma and as a part which cannot be determined by the pQCD theory. One method to handle this issue is Combine Models, which has its own advantages in dealing with small number of quarks. And a famous one of these models is SDQ.CM proposed by our group. In the last80th, on the basis of the fundamental graphic of Combine Models, Q. B. Xie and some others proposed the law of production and combination of quarks. In the law of combination of quarks, they obtained the function of probability distribution of definite number of baryons in given number of quarks and antiquarks by using permutation and combination. Our main goal in this thesis is to extend the law to situations which consider influences of net quarks.In order to obtain the new specific law, firstly we describe the law of near-correlation in rapidity, and how they obtain the function of probability distribution by using this. Then we calculate the result of this function under given number of quarks and give out the graphics of probability distribution of different number of quarks. And on the basis of these graphics we make some summary of this probability distribution. After doing this, we propose the form of the average number of baryons, anti-baryons and mesons produced in high energy process. Finally we achieve the ratio of the average number of baryons and mesons, which is1/6and provide an example of application of the law of combination of quarks in high energy process.On the basis of former law of combination of quarks, we successfully extend it into the situation which considers the influence of net quarks in the process of quark combination. Similarly, we obtain the function of probability distribution in this situation. The expression of this probability distribution is Then we calculate the result of this function under given number of quarks and given number of anti-quarks, and give out the graphics of probability distribution of different number of net quarks. And on the basis of these graphics we make some summary of this probability distribution. Finally, we obtain two expressions, which consider the influence of net quarks, of the average number of baryons, anti-baryons and mesons as a function of the ratio of net quarks and the total number of quarks by using two different methods. The two expressions both well satisfy the boundary conditions spontaneously which means our work is idealized. The First one is in the form of quadratic function. Its expression is <NB>(Nq,(Nnet)/(Nq))=[(0.1495±0.0026)((Nnet)/(Nq))2+(0.0776±0.0024))((Nnet)/(Nq))+0.1120]Nq. And the second one is in the form exponential function. Its expression isOn the basis of recent work, we have decided to do some further research on how the coefficients in the two expressions depend on the total number of quarks in order to obtain more generalized and specific results.