Speaker
Description
As one of the essential building blocks of ordinary matter, understanding the proton and the strong force that binds its constituents are of crucial importance. At low $Q^2$, the perturbative description of QCD fails, and it is necessary to employ effective theories such as Chiral Perturbation Theory. One way of directly testing these effective theories is the measurement of polarizabilities, which describe the ensemble response of the nucleon to an external field. In this talk, I will present the recently published measurements of several proton spin polarizabilities from the Jefferson Lab E08-027 (g2p) collaboration, $\delta_{LT}$ and $\overline{d_2}$, as well as the first low $Q^2$ measurement of the proton's $g_2$ structure function, which is used to extract these moments. These results are used to directly check several competing calculations from Chiral Perturbation Theory and act as a direct test on our understanding of QCD in the regime where the proton's constituents interact strongly.
| Submitted on behalf of a Collaboration? | Yes |
|---|
