Azimuthal angle dependence of di-jet production in unpolarized hadron scattering
Abstract
Description
We study the azimuthal angular dependence of back-to-back di-jet production in unpolarized hadron scattering $H_A+H_B \to J_1 + J_2 +X$, arising from the product of two Boer-Mulders functions, which describe the transverse spin distribution of quarks inside an unpolarized hadron. We find that when the di-jet is of two identical quarks ($J_q+J_q$) or a quark-antiquark pair ($J_q+J_{\bar{q}}$), there is a $\cos δϕ$ angular dependence of the di-jet, with $δϕ=ϕ_1-ϕ_2$, and $ϕ_1$ and $ϕ_2$ are the azimuthal angles of the two individual jets. In the case of $J_q+J_q$ production, we find that there is a color factor enhancement in the gluonic cross-section, compared with the result from the standard generalized parton model. We estimate the $\cos δϕ$ asymmetry of di-jet production at RHIC, showing that the color factor enhancement in the angular dependent of $J_q+J_q$ production will reverse the sign of the asymmetry.
10 pages, 7 figures, version accepted by Physical Review D
10 pages, 7 figures, version accepted by Physical Review D