Measurements of single diffraction using the ALFA forward spectrometer at ATLAS

Proton-proton collision data with a low pile-up at the energy $\sqrt{s} = 8$ TeV at the Large Hadron Collider with integrated luminosity 1.67 nb$^{−1}$ were collected by the ATLAS Collaboration and used to study inclusive single diffractive dissociation, pp $\rightarrow$ Xp. The intact forward going proton is measured in the ALFA spectrometer, while charged particles from the dissociated system X are measured in the central detector components. Cross sections are measured as functions of the proton fractional energy loss $\xi$, the squared four momentum transfer $t$, and the size of the visible part of the rapidity gap between the proton and the system X. The results are interpreted in the framework of Regge phenomenology.