Measurement of Polarization-Independent Azimuthal Asymmetries in the π-induced Drell-Yan Production in CERN/COMPASS Experiment

Wen-Chen Chang¹, Rurng-Sheng Guo³, Chia-Yu Hsieh², Yu-Shiang Lian^1,3*, Marcia Quaresma¹

¹Institute of Physics, Academia Sinica, Taipei, Taiwan
²Department of Physics, National Central University, Taoyuan, Taiwan
³Department of Physics, National Kaohsiung Normal University, Kaohsiung, Taiwan

* Presenter:Yu-Shiang Lian, email:yslian@gate.sinica.edu.tw

The angular distributions of unpolarized pion-induced Drell-Yan process are important information from which we explore both perturbative and non-perturbative QCD effects.

We measure Drell-Yan production from 190-GeV π^- interacting with NH₃ target in COMPASS experiment at CERN. In this talk, we will present the recent results of unpolarized azimuthal asymmetries (λ, μ, ν) in the pion-induced Drell-Yan process from the 2015 DY run. We will discuss the study of the Lam-Tung relation and transverse-momentum dependent Boer-Mulders functions with our result.

Keywords: Drell-Yan process, COMPASS experiment