BFKL versus O(α_s^3) Corrections to Large-rapidity Dijet Production
We examine dijet production at large rapidity intervals at Tevatron energies by comparing an exact ${\cal O}(α_s^3)$ calculation with the BFKL approximation, which resums the leading powers of the rapidity interval $y$ to all orders in $α_s$. We analyze the dependence of the exact ${\cal O}(α_s^3)$ calculation on the jet cone-size as a function of $y$, and use this cross section to define an ``effective rapidity'' $\hat y$ which reduces the error that the large-$y$ approximation induces on the kinematics. Using $\hat y$ in the BFKL resummation, we reexamine jet production at large transverse momenta and the transverse momentum decorrelation of the tagging jets. We find less dramatic, but still significant, effects than found previously using the large-$y$ approximation.