UNC-CH Physics and Astronomy Seminar

Chia Cheng Chang, RIKEN/LBL

“Precision nucleon structure calculations from lattice QCD”

The maturation of lattice quantum chromodynamics over the past decades has lead us to the point where percent-level precision for nucleon structure can be calculated directly from first principles. One such example is the calculation of the nucleon axial coupling, $g_A$, which parameterizes the coupling strength of the weak axial current to the nucleon. It has been estimated that a precision of two percent would be possible by 2020. However, today I will present the first determination of $g_A$ to one percent precision commensurate with measurements from experiment. Following the pursuit of testing the Standard Model through high precision, I will also discuss a (very) preliminary calculation of the proton radius, as well as other single nucleon structure calculations that are of interest in the future.