اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدDeciphering the $X(3872)$ via its polarization in prompt production at the CERN LHC
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Based on the hypothesis that the $X(3872)$ exotic hadron is a mixture of $chi_{c1}(2P)$ and other states and that its prompt hadroproduction predominately proceeds via its $chi_{c1}(2P)$ component, we calculate the prompt-$X(3872)$ polarization at the CERN LHC through next-to-leading order in $alpha_s$ within the factorization formalism of nonrelativistic QCD, including both the color-singlet $^3!P_1^{[1]}$ and color-octet $^3!S_1^{[8]}$ $cbar c$ Fock states. We also consider the polarization of the $J/psi$ produced by the subsequent $X(3872)$ decay. We predict that, under ATLAS, CMS, and LHCb experimental conditions, the $X(3872)$ is largely longitudinally polarized, while the $J/psi$ is largely transversely polarized. We propose that the LHC experiments perform such polarization measurements to pin down the nature of the $X(3872)$ and other $X$, $Y$, $Z$ exotic states with non-zero spin.
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