Studies of Transverse Momentum Dependent Parton Distributions and Bessel Weighting
M. Aghasyan, H. Avakian, E. De Sanctis, L. Gamberg, M. Mirazita, B. Musch, A. Prokudin, P. Rossi
备注：
30 pages, 8 figures, enhanced discussion and interpretation of results, new section on errors with an appendix, added references. Accepted for publication in JHEP
In this paper we present a new technique for analysis of transverse momentum dependent parton distribution functions, based on the Bessel weighting formalism. The procedure is applied to studies of the double longitudinal spin asymmetry in semi-inclusive deep inelastic scattering using a new dedicated Monte Carlo generator which includes quark intrinsic transverse momentum within the generalized parton model. Using a fully differential cross section for the process, the effect of four momentum conservation is analyzed using various input models for transverse momentum distributions and fragmentation functions. We observe a few percent systematic offset of the Bessel-weighted asymmetry obtained from Monte Carlo extraction compared to input model calculations, which is due to the limitations imposed by the energy and momentum conservation at the given energy/Q2. We find that the Bessel weighting technique provides a powerful and reliable tool to study the Fourier transform of TMDs with controlled systematics due to experimental acceptances and resolutions with different TMD model inputs.
Nuclear Science Division, Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室核科学部）；Department of Physics and Astronomy, University of California, Davis（加州大学戴维斯分校物理与天文学系）；Department of Physics, University of Washington（华盛顿大学物理系）；Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory（劳伦斯利弗莫尔国家实验室核与化学科学部）
