Moments and power corrections of longitudinal and transverse proton structure functions from lattice QCD

We present a simultaneous extraction of the moments of F2 and FL structure functions of the proton for a range of photon virtuality, Q2. This is achieved by computing the forward Compton amplitude on the lattice utilizing the second-order Feynman-Hellmann theorem. Our calculations are performed on configurations with two different lattice spacings and volumes, all at the SUo3 thorn symmetric point. We find the moments of F2 and FL in good agreement with experiment. Power corrections turn out to be significant. This is the first time the Q2 dependence of the lowest moment of F2 has been quantified.

Automated summary

We simultaneously extracted the moments of F2 and FL structure functions of the proton for a range of photon virtuality, Q2, by computing the forward Compton amplitude on the lattice using the second-order Feynman-Hellmann theorem. Our calculations were performed on configurations with two different lattice spacings and volumes, all at the SU(3) symmetric point. We found that the moments of F2 and FL were in good agreement with experiment, and the power corrections were significant. This is the first study to quantify the Q2 dependence of the lowest moment of F2.