https://doi.org/10.1051/epjconf/201920402006
How to measure the linear polarization of gluons in unpolarized proton using the heavy-quark pair production
1 Veksler and Baldin Laboratory of High Energy Physics, JINR, 141980 Dubna, Russia
2 Bogoliubov Laboratory of Theoretical Physics, JINR, 141980 Dubna, Russia
3 Yerevan Physics Institute, Alikhanian Br. 2, 0036 Yerevan, Armenia
* e-mail: nikiv@yerphi.am
Published online: 3 April 2019
In recent papers [1, 2], two new ways have been proposed to probe the linear polarization of gluons in unpolarized proton: using the azimuthal asymmetries and Callan-Gross ratio in heavy-quark pair leptoproduction, lN → l′QQ̅X. In this talk, we discuss in details the sensitivity of the QCD predictions for the azimuthal cos φ and cos 2φ asymmetries to the contribution of linearly polarized gluons inside unpolarized proton, where the azimuth φ is the angle between the lepton scattering plane (l, l′) and the heavy quark production plane (N, Q). Our analysis shows that the azimuthal distributions under consideration vary from 0 to 1 depending on the value of the gluonic counterpart of the Boer- Mulders function, 
. We conclude that the cos φ and cos 2φ asymmetries in heavy-quark pair production in DIS processes are predicted to be large in wide kinematic ranges and sensitive to the contribution of linearly polarized gluons.
© The Authors, published by EDP Sciences, 2019
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0 (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
