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arXiv · hep-ph/0110014

Positivity constraints on photon structure functions

K. Sasaki·J. Soffer·T. Uematsu
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Abstract

We investigate the positivity constraints for the structure functions of both virtual and real photon. From the Cauchy-Schwarz inequality we derive three positivity conditions for the general virtual photon case, which reduce, in the real photon case, to one condition relating the polarized and unpolarized structure functions.

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K. Sasaki, J. Soffer, T. Uematsu. 2001-10-24. Positivity constraints on photon structure functions. https://doi.org/10.1016/s0370-2693(01)01279-5

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