Parton distribution functions of Δ+ on the lattice

We perform a first calculation for the unpolarized parton distribution function of the Δ⁺ baryon using lattice QCD simulations within the framework of large momentum effective theory. Two ensembles of N_f=2 +1 +1 twisted mass fermions are utilized with a pion mass of 270 and 360 MeV, respectively. The baryon, which is treated as a stable single-particle state, is boosted with momentum P₃ with values {0.42 ,0.83 ,1.25 } GeV , and we utilize momentum smearing to improve the signal. The unpolarized parton distribution function of Δ⁺ is obtained using a nonperturbative renormalization and a one-loop formula for the matching, with encouraging precision. In particular, we compute the d ¯(x )-u ¯(x ) asymmetry and compare it with the same quantity in the nucleon, in a first attempt towards resolving the physical mechanism responsible for generating such asymmetry.