Total $\gamma^*$ p cross section

The Γ * P Total Cross Section and Elastic Diffraction

The empirical scaling law, wherein the total photoabsorption cross section depends on the single variable η = (Q 2 + m 2 0)/Λ 2 (W 2), provides empirical evidence for saturation in the sense of σγ * p(W 2 , Q 2)/σγp(W 2) → 1 for W 2 → ∞ at fixed Q 2. The total photoabsorption cross section is related to elastic diffraction in terms of a sum rule. The excess of diffractive production over the el...

The total charm cross section

We assess the theoretical uncertainties on the total charm cross section. We discuss the importance of the quark mass, the scale choice and the parton densities on the estimate of the uncertainty. We conclude that due to the small charm quark mass, which amplifies the effect of varying the other parameters in the calculation, the uncertainty on the total charm cross section is difficult to

gamma cross section in p plus p collisions at root s=200 GeV

Photon-photon Total Inelastic Cross-section *

We discuss predictions for the total inelastic γγ cross-section and their model dependence on the input parameters. We compare results from a simple extension of the Regge Pomeron exchange model as well as predictions from the eikonalized mini-jet model with recent LEP data. It is by now established that all total cross-sections, including photopro-duction, rise as the c.m. energy of the collid...

The Elusive p-air Cross Section

For the p̄p and pp systems, we have used all of the extensive data of the Particle Data Group[K. Hagiwara et al. (Particle Data Group), Phys. Rev. D 66, 010001 (2002).]. We then subject these data to a screening process, the “Sieve” algorithm[M. M. Block, physics/0506010.], in order to eliminate “outliers” that can skew a χ2 fit. With the “Sieve” algorithm, a robust fit using a Lorentzian distri...