Sivers and cos2ϕ asymmetries in semi-inclusive deep inelastic scattering in light-front holographic model

Abstract

The spin asymmetries in SIDIS associated with T -odd TMDs are presented in a light-front quarkdiquark model of a proton. To incorporate the effects of the final state interaction, the light front wave functions are modified to have a phase factor which is essential to have Sivers or Boer-Mulders functions. The Sivers and Boer-Mulder asymmetries are compared with HERMES and COMPASS data.

Sivers distribution functions of sea quarks in a proton with the chiral Lagrangian

“…Though the quasi-PDFs are proposed to be calculated on lattice based on the large momentum effective theory (LaMET) [8], the simulation of PDFs on Lattice is still in the early stage. For the Sivers distribution function, most calculations are based on the phenomenological quark models, such as spectator model [9][10][11][12][13][14][15][16], MIT bag model [17], constituent quark model [18,19], etc. In these model calculations, the gluon field is introduced as the gauge link.…”

Relations between generalized parton distributions and transverse momentum dependent parton distributions

“…In this model, the contribution of the FSI is included in the light-front wave functions [15] to evaluate the leading twist T-odd TMDs, i.e., the Sivers function, f ⊥q 1T (x, p 2 T ) and the Boer-Mulders function, h ⊥q 1 (x, p 2 T ). The modified wave functions [16] are given by (a) for scalar diquark…”

“…The GPD correlators (Eqs. (15)(16)(17) ) for different Γ in the impact parameter space are then obtained [9] as…”

“…( 37), we can easily check that Boer-Mulders function is proportional to the Sivers function. The Boer-Mulders function can be parametrized [16,35] as…”

“…(x 0 ± x 3 ), x T = (x 1 , x 2 ). We choose the light-front gauge A + = 0, so that the gauge link appearing in between the quark fields in Eqs (15)(16)(17). becomes unity.…”