Physics Commons^™

High Precision Determination Of The Q² Evolution Of The Bjorken Sum, A. Deur, Y. Prok, V. Burkert, D. Crabb, F. X. Girod, K. A. Griffioen, N. Guler, S. E. Kuhn, N. Kvaltine

Physics Faculty Publications

We present a significantly improved determination of the Bjorken sum for 0.6 ≤ Q² ≤ 4.8 GeV² using precise new g^p₁ and g^d₁ data taken with the CLAS detector at Jefferson Lab. A higher-twist analysis of the Q² dependence of the Bjorken sum yields the twist-4 coefficient f ^p-n₂= -0.064 ± 0.009 ± ^0.032 _0.036. This leads to the color polarizabilities χ ^p-n _E= -0.032 ± 0.024 and χ^p-n_B= 0.032 ± 0.013. The strong force coupling is determined to be α ^MS_S (M²_{Z …}