Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
2002-11-07
Phys.Rev.D67:054003,2003
Physics
High Energy Physics
High Energy Physics - Phenomenology
22 pages, 6 figures
Scientific paper
10.1103/PhysRevD.67.054003
We show that initial-state interactions contribute to the $\cos 2 \phi$ distribution in unpolarized Drell-Yan lepton pair production $p p$ and $ p \bar p \to \ell^+ \ell^- X$, without suppression. The asymmetry is expressed as a product of chiral-odd distributions $h_1^\perp(x_1,\bm{p}_\perp^2)\times \bar h_1^\perp(x_2,\bm{k}_\perp^2) $, where the quark-transversity function $h_1^\perp(x,\bm{p}_\perp^2)$ is the transverse momentum dependent, light-cone momentum distribution of transversely polarized quarks in an {\it unpolarized} proton. We compute this (naive) $T$-odd and chiral-odd distribution function and the resulting $\cos 2 \phi$ asymmetry explicitly in a quark-scalar diquark model for the proton with initial-state gluon interaction. In this model the function $h_1^\perp(x,\bm{p}_\perp^2)$ equals the $T$-odd (chiral-even) Sivers effect function $f^\perp_{1T}(x,\bm{p}_\perp^2)$. This suggests that the single-spin asymmetries in the SIDIS and the Drell-Yan process are closely related to the $\cos 2 \phi$ asymmetry of the unpolarized Drell-Yan process, since all can arise from the same underlying mechanism. This provides new insight regarding the role of quark and gluon orbital angular momentum as well as that of initial- and final-state gluon exchange interactions in hard QCD processes.
Boer Daniel
Brodsky Stanley J.
Hwang Dae Sung
No associations
LandOfFree
Initial-State Interactions in the Unpolarized Drell-Yan Process does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Initial-State Interactions in the Unpolarized Drell-Yan Process, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Initial-State Interactions in the Unpolarized Drell-Yan Process will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-469930