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$\Upsilon(nS)$ and $\chi_b(nP)$ production at hadron colliders in nonrelativistic QCD

Authors :
Han, H.
Ma, Y. Q.
Meng, C.
Shao, H. S.
Zhang, Y. J.
Chao, K. T.
Source :
Phys. Rev. D 94, 014028 (2016)
Publication Year :
2014

Abstract

$\Upsilon(nS)$ and $\chi_b(nP)$ (n=1,2,3) production at the LHC is studied at next-to-leading order in $\alpha_s$ in nonrelativistic QCD. Feeddown contributions from higher $\chi_b$ and $\Upsilon$ states are all considered for lower $\Upsilon$ cross sections and polarizations. The long distance matrix elements (LDMEs) are extracted from the yield data, and then used to make predictions for the $\Upsilon(nS)$ polarizations, which are found to be consistent with the measured polarization data within errors. In particular, the $\Upsilon(3S)$ polarization puzzle can be understood by a large feeddown contribution from $\chi_b(3P)$ states. Our results may provide a good description for both cross sections and polarizations of prompt $\Upsilon(nS)$ and $\chi_b(nP)$ production at the LHC.<br />Comment: The text and abstract are substantially changed due to the change in the fitting procedure: we now extract LDMEs of $\Upsilon(nS)$ and $\chi_b{nP}$ by fitting the yield data of the LHC (including cross sections measured by ATLAS, CMS, and LHCb), and then make predictions for the polarizations of $\Upsilon(nS)$

Details

Database :
arXiv
Journal :
Phys. Rev. D 94, 014028 (2016)
Publication Type :
Report
Accession number :
edsarx.1410.8537
Document Type :
Working Paper
Full Text :
https://doi.org/10.1103/PhysRevD.94.014028