Polarizations of ${\chi }_{c1}$ and ${\chi }_{c2}$ in prompt production at the LHC

Abstract

Prompt ${\chi }_c$ production at hadron colliders may provide a unique test for the color-octet mechanism in nonrelativistic QCD. We present an analysis for the polarization observables of ${\chi }_{c1}$ and ${\chi }_{c2}$ at next-to-leading order in ${\alpha }_S$, and propose to measure them at the LHC, which is expected to be important for testing the validity of NRQCD.

Comments: Version published in PRL, 5 pages, 5 figures (Fig.2 is added to show contributions of each intermediate states)