Drell-Yan cross section measurement at COMPASS

Chia-Yu Hsieh^1*, Wen-Chen Chang¹, Vincent Andreux², Catarina Quintans³

¹Institute of Physics, Academia Sinica, Taipei, Taiwan
²Department of Physics, University of Illinois Urbana-Champaign, Illinois, USA
³Physics, Laboratory of Instrumentation and Experimental Particle Physics, Lisboa, Portugal

* Presenter:Chia-Yu Hsieh, email:cyhsieh0531@gmail.com

The COMPASS experiment at CERN performed measurements of the Drell-Yan process using a 190 GeV negative pion beam scattering off a NH3 target and nuclear aluminium and tungsten targets, in the years 2015 and 2018. We present the results of differential cross sections of the dimuon events with the invariant mass between 4.3 and 8.5 GeV/c² in the kinematic regions of x-Feynman from -0.2 to 0.9 and transverse momentum up to 3.6 GeV/c. The measured differential cross sections are compared with the next-to-next-leading order QCD calculations and a reasonable agreement is observed. Our results are valuable input for constraining the PDF and the TMD of the pion. Furthermore, the nuclear effect is studied through the comparison of result from different targets.

Keywords: Drell-Yan cross section, Pion PDF, Pion TMD, Nuclear effect