Measurements of the inclusive jet cross section with the anti-kT clustering algorithm are presented for two radius parameters, R=0.5 and 0.7. They are based on data from LHC proton-proton collisions at s=7TeV corresponding to an integrated luminosity of 5.0fb-1 collected with the CMS detector in 2011. The ratio of these two measurements is obtained as a function of the rapidity and transverse momentum of the jets. Significant discrepancies are found comparing the data to leading-order simulations and to fixed-order calculations at next-to-leading order, corrected for nonperturbative effects, whereas simulations with next-to-leading-order matrix elements matched to parton showers describe the data best.
Chatrchyan, S., Khachatryan, V., Sirunyan, A. M., Tumasyan, A., Adam, W., Bergauer, T., … Smith, W. H. (2014). Measurement of the ratio of inclusive jet cross sections using the anti- k T algorithm with radius parameters R=0.5 and 0.7 in pp collisions at s =7TeV. Physical Review D - Particles, Fields, Gravitation and Cosmology, 90(7). https://doi.org/10.1103/PhysRevD.90.072006