Physics Commons^™

Experimental Study Of Isovector Spin Sum Rules, A. Deur, P. Bosted, V. Burkert, D. Crabb, V. Dharmawardane, G. E. Dodge, T. A. Forest, K. A. Griffioen, S. E. Kuhn, R. Minehart, Y. Prok

Physics Faculty Publications

We present the Bjorken integral extracted from Jefferson Lab experiment EG1b for 0.05< Q² 2. The integral is fit to extract the twist-4 element f ^p−n₂ which appears to be relatively large and negative. Systematic studies of this higher twist analysis establish its legitimacy at Q² around 1  GeV². We also performed an isospin decomposition of the generalized forward spin polarizability γ₀. Although its isovector part provides a reliable test of the calculation techniques of chiral perturbation theory, our data disagree with the calculations.