Paper
Testing Charmonium Production Mechanism via Polarized $J/ψ$ Pair Production at the LHC
Authors
Abstract
At present the color-octet mechanism is still an important and debatable part in the non-relativistic QCD(NRQCD). We find in this work that the polarized double charmonium production at the LHC may pose a stringent test on the charmonium production mechanism. Result shows that the transverse momentum() scaling behaviors of double differential cross sections in color-singlet and -octet production mechanisms deviate distinctively from each other while is larger than 7 GeV. In color-octet mechanism, the two s in one pair are mostly transversely polarized when , as expected from the fragmentation limit point of view. In color-singlet mechanism, there is about one half of the charmonium pairs with at least one being longitudinally polarized at moderate transverse momentum. The energy dependence of the polarized pair production is found to be weak, and this process is found to be experimentally attainable in the early phase of the LHC operation.