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A New Measurement of Exclusive \boldmath$ρ^{\circ}$ Photoproduction at HERA

J. Olsson
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Abstract

Exclusive $ρ^{\circ}$ photoproduction has been measured with high statistics by the H1 Collaboration. The kinematical range is $20 < W < 90$ GeV, $|t|<3$ GeV$^2$ and $Q^2<4$ GeV$^2$. Cross sections are measured differentially in $W$ and $t$ and allow the extraction of the Pomeron trajectory, for the first time using $ρ^{\circ}$ photoproduction data of one single experiment. The preliminary result, $α_{\mathbb{P}} (t) = 1.093 \pm 0.003 (stat.) ^{+0.008}_{-0.007} (syst.) + (0.116 \pm 0.027 (stat.) ^{+0.036}_{-0.046} (syst.)$ GeV$^{-2} \cdot t$, deviates significantly from the canonical expectation.

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J. Olsson. 2006-10-25. A New Measurement of Exclusive \boldmath$ρ^{\circ}$ Photoproduction at HERA. https://doi.org/10.1142/9789812706706_0051

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