  A search for new heavy particles manifested as resonances in two-jet final
states is presented. The data were produced in root(s) = 7 TeV proton-proton
collisions by the Large Hadron Collider (LHC) and correspond to an integrated
luminosity of 315 nb^-1 collected by the ATLAS detector. No resonances were
observed. Upper limits were set on the product of cross section and signal
acceptance for excited-quark (q*) production as a function of q* mass. These
exclude at the 95% CL the q* mass interval 0.30 < m(q*) < 1.26 TeV, extending
the reach of previous experiments.
