Inclusive cross sections of proton-proton and proton-antiproton scattering

Abstract

We have predicted the difference in inclusive cross sections on pseudorapidity in $\mathrm{d}{\sigma }^{p\bar{p}}/\mathrm{d}\eta$ and $\mathrm{d}{\sigma }^{pp}/\mathrm{d}\eta$ interactions at $\sqrt{s}=900$~GeV. Their ratio $R=\left(\mathrm{d}{\sigma }^{p\bar{p}}/\mathrm{d}\eta \right)/\left(\mathrm{d}{\sigma }^{pp}/\mathrm{d}\eta \right)>1$ in the whole pseudorapidity range. On the basis of AGK theorem we show that the ratio of inclusive cross sections of $pp$ and $p\bar{p}$ at $\sqrt{s}=900$~GeV in the region of low transverse momenta $p_{\perp }$ up to 2~GeV $\left(\frac{1}{2\pi p_{\perp }}\frac{{\mathrm{d}}^2{\sigma }^{p\bar{p}}}{\mathrm{d}\eta \mathrm{d}{p}_{\perp }}\right)/\left(\frac{1}{2\pi p_{\perp }}\frac{{\mathrm{d}}^2{\sigma }^{pp}}{\mathrm{d}\eta \mathrm{d}{p}_{\perp }}\right)=R$. Experimental measurements by the ATLAS Coll. give value $R\simeq 1.2$ for interval $|\eta |<2.5$. The difference in inclusive cross sections results from presence of additional subprocess in $p\bar{p}$ -- hadrons production from decay of three quark strings, which is absent in $pp$ scattering.

Comments: Talk presented at the ISMD 2010, Antwerp (Belgium). Some typos are corrected