Using the scale evolution of nuclear parton distributions,the contribution of color-octet heavy quarkonium production mechanism to the P + Fe → J/ψ + γ + X process in calculated and discussed.Comparing our theoreti...Using the scale evolution of nuclear parton distributions,the contribution of color-octet heavy quarkonium production mechanism to the P + Fe → J/ψ + γ + X process in calculated and discussed.Comparing our theoretical results with the future experimental data,the color-octet heavy quarkonium production mechanism can be examined.展开更多
The extended x-rescaling model can explain the quark's nuclear effect very well. Weather it can also explain the gluon's nuclear effect should be investigated further. Associated J/ψ and γ production with la...The extended x-rescaling model can explain the quark's nuclear effect very well. Weather it can also explain the gluon's nuclear effect should be investigated further. Associated J/ψ and γ production with large PT is a very clean channel to probe the gluon distribution in proton or nucleus. In this paper, using the extended x-rescaling model, the PT distribution of the nuclear effect factors of p + Fe → J/Ψ + γ+ X process is calculated and discussed. Comparing our theoretical results with the future experimental data, the extended x-rescaling model can be examined.展开更多
Using three sets of Pomeron structure functions, the cross sections of J/ψ and γ associated productionvia resolved photon and proton diffractive scatting in ep collision are investigated. It is found that the cross ...Using three sets of Pomeron structure functions, the cross sections of J/ψ and γ associated productionvia resolved photon and proton diffractive scatting in ep collision are investigated. It is found that the cross sectionscalculated with various gluon distribution functions of Pomeron are different. The discrepancy is about 1.8 times fordifferential cross sections and 1.7 times for total cross sections. The experimental studies of the process could give valuableinsight in the diffractive production mechanism and test the color-octet mechanism for heavy quarkonium production ina new environment.展开更多
DJpsiFDC is an event generator package for the process gg → J/ψJ/ψ. It generates events for primary leading-order 2 → 2 processes. The package could generate a Les Houches Event (LHE) document and this could eas...DJpsiFDC is an event generator package for the process gg → J/ψJ/ψ. It generates events for primary leading-order 2 → 2 processes. The package could generate a Les Houches Event (LHE) document and this could easily be embedded into detector simulation software frameworks. The package is produced in Fortran code.展开更多
We study the J/ψ pair production issue at the Fermilab Tevatron Run II with a center-of-mass energy of s^(1/2)=1.96TeV. Both the color-singlet and color-octet production mechanisms are considered. Our results show ...We study the J/ψ pair production issue at the Fermilab Tevatron Run II with a center-of-mass energy of s^(1/2)=1.96TeV. Both the color-singlet and color-octet production mechanisms are considered. Our results show that the transverse momentum (pT) scaling behaviors of the double J/ψ differential cross-sections in the color-singlets and color-octets deviate distinctively from each other while pT is larger than 8GeV, and with a luminosity of 5fb^-1 , the J/ψ pair events from the color-singlet scheme are substantially measurable in the Tevatron experiments, even with a certain lower transverse momentum cut. Hence the Tevatron is still a possible platform to check the heavy quarkonium production mechanism.展开更多
文摘Using the scale evolution of nuclear parton distributions,the contribution of color-octet heavy quarkonium production mechanism to the P + Fe → J/ψ + γ + X process in calculated and discussed.Comparing our theoretical results with the future experimental data,the color-octet heavy quarkonium production mechanism can be examined.
文摘The extended x-rescaling model can explain the quark's nuclear effect very well. Weather it can also explain the gluon's nuclear effect should be investigated further. Associated J/ψ and γ production with large PT is a very clean channel to probe the gluon distribution in proton or nucleus. In this paper, using the extended x-rescaling model, the PT distribution of the nuclear effect factors of p + Fe → J/Ψ + γ+ X process is calculated and discussed. Comparing our theoretical results with the future experimental data, the extended x-rescaling model can be examined.
基金The project supported in part by "High Energy Particle-Nuclear Interaction" (10175074) from National Natural Science Foundation of China, Natural Science Foundation of Hebei Province of China (100114), and the Youth Foundation of North China Electric Power University
文摘Using three sets of Pomeron structure functions, the cross sections of J/ψ and γ associated productionvia resolved photon and proton diffractive scatting in ep collision are investigated. It is found that the cross sectionscalculated with various gluon distribution functions of Pomeron are different. The discrepancy is about 1.8 times fordifferential cross sections and 1.7 times for total cross sections. The experimental studies of the process could give valuableinsight in the diffractive production mechanism and test the color-octet mechanism for heavy quarkonium production ina new environment.
基金The project supported in part by National Natural Science Foundation of China under Grant No. 10421503 and the Key Project of the Ministry of Education under Grant No. 305001, and the Research Found of Doctorial Programs of Higher Education of China. We thank E. Berger for bringing their earlier work on inelastic photoproduction of T (Ref. [12]) to our attention. We would also like to thank Ce Meng for valuable discussions.
基金Supported by National Natural Science Foundation of China (10935012, 10928510, 10821063, 10775179)CAS Key Projects(KJCX2-yw-N29, H92A0200S2)100 Talents Program of CAS
文摘DJpsiFDC is an event generator package for the process gg → J/ψJ/ψ. It generates events for primary leading-order 2 → 2 processes. The package could generate a Les Houches Event (LHE) document and this could easily be embedded into detector simulation software frameworks. The package is produced in Fortran code.
基金Supported by National Natural Science Foundation of China (10935012, 10821063, 11175249)
文摘We study the J/ψ pair production issue at the Fermilab Tevatron Run II with a center-of-mass energy of s^(1/2)=1.96TeV. Both the color-singlet and color-octet production mechanisms are considered. Our results show that the transverse momentum (pT) scaling behaviors of the double J/ψ differential cross-sections in the color-singlets and color-octets deviate distinctively from each other while pT is larger than 8GeV, and with a luminosity of 5fb^-1 , the J/ψ pair events from the color-singlet scheme are substantially measurable in the Tevatron experiments, even with a certain lower transverse momentum cut. Hence the Tevatron is still a possible platform to check the heavy quarkonium production mechanism.