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

The transverse-energy flow generated by minijets in hadron and nuclear coll isions 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 tr ansverse-energy production in pp collision cross sections is larger than th at in the leading-order (LO) ones by the factors of K-RHIC similar to 1.9 a nd K-LHC similar to 2.1 at RHIC and LHC energies, respectively. These resul ts were then used to calculate the transverse-energy spectrum in nuclear co llisions in a Glauber geometrical model. We show that accounting for NLO co rrections in the elementary pp collisions leads to a substantial broadening of the El distribution for the nuclear ones, while its form remains practi cally unchanged.