9-14 September 2018
University of Ferrara
Europe/Rome timezone

Lattice QCD calculations of the quark and gluon contributions to the proton spin

14 Sep 2018, 11:30
Teatro Nuovo - Piazza Trento e Trieste, 52

Teatro Nuovo - Piazza Trento e Trieste, 52

Piazza Trento e Trieste, 52
Plenary Sessions (for INVITED PLENARY TALKS only!) Nucleon Helicity Structure Plenary


Dr Rajan Gupta (Los Alamos National Lab)


The remarkable result, from the measurements of spin asymmetry in polarized deep inelastic scattering by the EMC collaboration, that the sum of the spins of the quarks contributes less than half of the total spin of the proton lay down the challenge to explain this “proton spin crisis” from QCD. I will show that calculations of the required matrix elements using Lattice QCD are now in a position to provide first principle results with all systematics under control and the steady reduction in the error budget. The most well determined of the contributions is of the quark's intrinsic spin. Existing lattice results will be reviewed and compared with current phenomenological/experimental estimates.

Primary author

Dr Rajan Gupta (Los Alamos National Lab)

Presentation Materials