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arXiv · 0807.0963

The Ratio of sigma_L(W2, Q2)/sigma_T(W2, Q2) in the Color Dipole Picture

Dieter Schildknecht
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Abstract

The transverse size of q q-bar fluctuations of the longitudinal photon is reduced relative to the transverse size of q q-bar fluctuations of the transverse photon. This implies R(W^2, Q^2) = 0.375 or, equivalently, F_L(W^2,Q^2)/F_2(W^2,Q^2) = 0.27 for x = Q^2/W^2 << 1 and Q^2 sufficiently large, while R(W^2, Q^2) = 0.5, if this effect is not taken into account. Forthcoming experimental data from HERA will allow to test this prediction.

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Dieter Schildknecht. 2008-07-07. The Ratio of sigma_L(W2, Q2)/sigma_T(W2, Q2) in the Color Dipole Picture. https://arxiv.org/abs/0807.0963

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