  Recently, the CMS and ATLAS Collaborations at the CERN Large Hadron Collider
(LHC) have set exclusion limits on the quark compositeness scale by comparing
their data to the leading order and the scaled next-to-leading order (NLO) QCD
calculations, respectively. In this Letter, we present the exact NLO QCD
corrections to the dijet production induced by the quark contact interactions.
We show that as compared to the exact calculation, the scaled NLO QCD
prediction adopted by the ATLAS Collaboration has overestimated the new physics
effect on some direct observables by more than 30% and renders a higher limit
on the quark compositeness scale. The destructive contribution from the exact
NLO correction will also lower the compositeness scale limit set by the CMS
Collaboration.
