Conveners
Baryon Structure
- Phiala Shanahan (Massachusetts Institute of Technology)
Description
co-host: Dave Gaskell
Radiative transitions between strongly stable hadrons and hadronic resonances offer a direct probe of the charge distribution within the resonance and can provide insightful revelations on the composition of hadronic resonances. This talk presents a toy-model investigation on the determination of 1 to 2 infinite-volume transition amplitudes from finite-volume matrix elements as would be...
Electroweak form-factors provide information about the internal structure of hadrons; however, short-lived strong resonances are challenging to probe experimentally. In this talk, I will outline a procedure to calculate the elastic form-factors of resonances directly from QCD. This approach relies on computing finite volume matrix elements via lattice QCD, and a formalism to relate these to...
The neutron is a cornerstone in our depiction of the visible universe. Despite the neutron zero-net electric charge, the asymmetric distribution of the positively- (up) and negatively-charged (down) quarks, a result of the complex quark-gluon dynamics, lead to a negative value for its squared charge radius. The precise measurement of the neutron's charge radius thus emerges as an essential...
Calculations of nucleon structure using lattice QCD are approaching the level of precision necessary to make important impacts on experimental programs. This talk will explore multiple theoretical approaches to calculations of the nucleon axial charge. We present numerical evidence and show that the various approaches have significantly different dependence on excited-state, yielding to...
The striking discrepancy in the proton form factor ratio, $\mu_p G_E^p/G_M^p$, measured using unpolarized and polarized techniques is still not resolved. The proposed explanation is that hard two-photon exchange (TPE) is responsible. Hard TPE is difficult to calculate without significant model dependence, and has generally not been included as a radiative correction. Furthermore, three...
