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Total Widths And Slopes From Complex Regge Trajectories

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 نشر من قبل Name
 تاريخ النشر 1998
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Maximally complex Regge trajectories are introduced for which both Re $alpha(s)$ and Im $alpha(s)$ grow as $s^{1-epsilon}$ ($epsilon$ small and positive). Our expression reduces to the standard real linear form as the imaginary part (proportional to $epsilon$) goes to zero. A scaling formula for the total widths emerges: $Gamma_{TOT}/Mto$ constant for large M, in very good agreement with data for mesons and baryons. The unitarity corrections also enhance the space-like slopes from their time-like values, thereby resolving an old problem with the $rho$ trajectory in $pi N$ charge exchange. Finally, the unitarily enhanced intercept, $alpha_{rho}approx 0.525$, olinebreak is in good accord with the Donnachie-Landshoff total cross section analysis.

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