Disconnected Contributions to Nucleon Form Factors

Collaborators:

Abstract:

We propose to begin initial calculations of the strange quark contributions to the electroweak elastic nucleon form factors G_E^s(Q²), G_M^s(Q²), G_S^s(Q²) and G_A^s(Q²) using Domain Wall fermions. Even though this will represent a new exploratory effort, we will be building on our experience doing the same calculations on anisotropic Wilson lattices. The use of Domain Wall fermions should greatly reduce the mixing associated with the scalar form factor which was the major source of error. Our plan is to use the Domain Wall lattices generated by the RBC and UKQCD collaborations that are available to USQCD. We have made major advances in algorithm and code development related to Wilson quarks and are currently using multigrid and GPU codes in production. We are now working to make the same advances for Domain Wall fermions which we will apply to this project as the codes are ready. To perform the initial set of runs we are asking for 55k GPU hours.

Progress:

We finished calculating the currents on the 2 flavor anisotropic Wilson lattices generated by the LHPC Spectrum collaboration.

We are finishing the currents on the 2+1 flavor anisotropic Wilson clover lattices.

We are beginning the analysis on 2+1 flavor Domain Wall configurations.