Pion parton distribution function in light-front holographic QCD *
Lei Chang, Khépani Raya, Xiaobin Wang
Abstract
Abstract The valence-quark distribution function of the pion has been of interest for decades; particularly, the profile it should adopt when (the large- x behavior) has been the subject of a long-standing debate. In the light-front holographic QCD (LFHQCD) approach, this behavior is controlled by the so-called reparametrization function, , which is not fully determined from first principles. We show that, owing to the flexibility of , the large- x profile can be contained within the LFHQCD formalism. This is in contrast to a previous LFHQCD study (Guy F. de Teramond et al., Phys. Rev. Lett., 120(18), 2018) in which was found instead. Given our observations, augmented by perturbative QCD and recent lattice QCD results, we state that the large- x exponent of “2” cannot be excluded.