Measurement of the dependence of transverse energy production at large pseudorapidity on the hard scattering kinematics of proton-proton collisions at $\sqrt{s}= 2.76$ TeV with the ATLAS detector

The relationship between jet production in the central region and the underlying event activity in a pseudorapidity separated region is studied in 4.0 pb$^{-1}$ of $\sqrt{s}$ = 2.76 TeV $pp$ events recorded with the ATLAS detector at the LHC. The hard scattering is characterised by the average transverse momentum and pseudorapidity of the two highest transverse momentum jets in the event. It is also presented as a function of the scaled longitudinal momenta of the hard-scattered partons in the target and projectile beam-protons Transverse energy production at large pseudorapidity is observed to vary strongly with the longitudinal momentum fraction in the target proton and only weakly with that in the projectile proton.