Minijet transverse-energy production in the next-to-leading order in hadron and nuclear collisions

Abstract. The transverse-energy flow generated by minijets in hadron and nuclear collisions into a given rapidity window in the central region is calculated in the next-to-leading-order (NLO) in QCD at RHIC and LHC energies. The NLO transverse-energy production in pp collision cross sections is larger than that in the leading-order (LO) ones by the factors of $K_{\rm RHIC} \sim 1.9$ and $K_{\rm LHC} \sim 2.1$ at RHIC and LHC energies, respectively. These results were then used to calculate the transverse-energy spectrum in nuclear collisions in a Glauber geometrical model. We show that accounting for NLO corrections in the elementary pp collisions leads to a substantial broadening of the $E_{\perp}$ distribution for the nuclear ones, while its form remains practically unchanged.