Gong Bin, Wan Lu-Ping, Wang Jian-Xiong, Zhang Hong-Fei
Institute of High Energy Physics, Chinese Academy of Sciences, P. O. Box 918(4), Beijing 100049, China and Theoretical Physics Center for Science Facilities, CAS, Beijing 100049, China and Institute of Theoretical Physics, Chinese Academy of Sciences, P. O. Box 2735, Beijing 100190, China.
Institute of High Energy Physics, Chinese Academy of Sciences, P. O. Box 918(4), Beijing 100049, China and Theoretical Physics Center for Science Facilities, CAS, Beijing 100049, China.
Phys Rev Lett. 2013 Jan 25;110(4):042002. doi: 10.1103/PhysRevLett.110.042002.
With nonrelativistic QCD factorization, we present the first complete next-to-leading order study on the polarization of prompt J/ψ hadroproduction by including feeddown from χ(c)((3)P(J)(1),(3)S(1)(8)) and ψ(2s) which turn out to be very important parts. By using the color-octet long-distance matrix elements obtained from a combined fit of the measurements at the Tevatron and LHC for J/ψ, ψ(2s) and χ(c), the prompt J/ψ polarization predictions are presented, and the results are in agreement with the CDF run I data (except two points), but in conflict with the CDF run II data, while they are close to the ALICE data (inclusive J/ψ). The measurements at the LHC are expected to clarify the situation.
利用非相对论性量子色动力学因子化方法，我们首次给出了关于即时J/ψ强子产生极化的完整次领头阶研究，其中包括来自χ(c)(（3）P(J)(1)，(3)S(1)(8)）和ψ(2s)的衰变贡献，结果表明它们是非常重要的部分。通过使用从Tevatron和LHC对J/ψ、ψ(2s)和χ(c)测量的联合拟合中获得的色八重态长程矩阵元，给出了即时J/ψ极化的预测结果，该结果与CDF一期运行数据（除两点外）一致，但与CDF二期运行数据冲突，同时与ALICE数据（包含性J/ψ）接近。预计LHC的测量将澄清这种情况。
