Corrections to the Glauber Model of High-Energy Scattering

We study the modifications to the Glauber model when the principal-value part of the double-scattering term is also taken into account. An estimate of the importance of this term is made by studying its effect first on the values of the ratios of the real to imaginary parts ${\alpha }_{\mathrm{pp}}$ and ${\alpha }_{\mathrm{pn}}$ of the $p-p$ and $n-p$ amplitudes, respectively, and second on the cross-section defect. We observe that this principal-value term makes its most significant contribution in the region of interference between single and double scattering and can therefore influence the values of ${\alpha }_{\mathrm{pp}}$ and ${\alpha }_{\mathrm{pn}}$ obtained from the best fits to the proton-deuteron scattering data.