Constraining the pion distribution amplitude using Drell-Yan reactions on a proton

Physics Letters B, vol. 849, pp. 138462

Abstract

Using a reaction model that incorporates pion bound state effects and continuum results for proton parton distributions and the pion distribution amplitude, φπ, we deliver parameter-free predictions for the μ+ angular distributions in πN→μ+μ−X reactions on both unpolarised and polarised targets. The analysis indicates that such angular distributions are sensitive to the pointwise form of φπ and suggests that unpolarised targets are practically more favourable. The precision of extant data is insufficient for use in charting φπ; hence, practical tests of this approach to charting φπ must await data with improved precision from new-generation experiments. The reaction model yields a nonzero single-spin azimuthal asymmetry, without reference to T-odd parton distribution functions (DFs). This may necessitate additional care when attempting to extract such T-odd DFs from data.

Authors 6

1. H. Xing

   Nanjing University

   Affiliation as printed

   Institute for Nonperturbative Physics, Nanjing University, Nanjing, Jiangsu 210093, China

   School of Physics, Nanjing University, Nanjing, Jiangsu 210093, China

2. Minghui Ding corresponding

   Helmholtz-Zentrum Dresden-Rossendorf

   Affiliation as printed

   Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, D-01328 Dresden, Germany

3. Zhu-Fang Cui corresponding

   Nanjing University

   Affiliation as printed

   Institute for Nonperturbative Physics, Nanjing University, Nanjing, Jiangsu 210093, China

   School of Physics, Nanjing University, Nanjing, Jiangsu 210093, China

4. A. V. Pimikov

   Nanjing University

   Affiliation as printed

   Institute for Nonperturbative Physics, Nanjing University, Nanjing, Jiangsu 210093, China

5. Craig D. Roberts corresponding

   Nanjing University

   Affiliation as printed

   Institute for Nonperturbative Physics, Nanjing University, Nanjing, Jiangsu 210093, China

   School of Physics, Nanjing University, Nanjing, Jiangsu 210093, China

6. Sebastian M. Schmidt Aachen III. Physikalisches Institut B

   Helmholtz-Zentrum Dresden-Rossendorf · RWTH Aachen University

   Affiliation as printed

   Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, D-01328 Dresden, Germany

   RWTH Aachen University, III. Physikalisches Institut B, D-52074 Aachen, Germany