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arXiv · 0807.0170

GPD sum rules: a tool to reveal the quark angular momentum

K. Kumericki·D. Mueller·K. Passek-Kumericki
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Abstract

In deeply virtual exclusive electroproduction to leading order accuracy one accesses generalized parton distributions on their cross-over trajectory. Combining Lorentz covariance and analyticity leads to a family of GPD sum rules, guiding us to phenomenological concepts. As an example, we discuss the constraints from the JLAB/Hall A data on the GPD $E$. Its first Mellin moment is the anomalous gravitomagnetic moment, which is the unknown contribution to the quark angular momentum.

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K. Kumericki, D. Mueller, K. Passek-Kumericki. 2008-07-01. GPD sum rules: a tool to reveal the quark angular momentum. https://arxiv.org/abs/0807.0170

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