Mueller-Navelet and exclusive dijets with extra jet veto at large rapidity separation in pp collisions at \sqrt(s) = 2.76 TeV

Ratios of dijet production cross sections were measured as a function of the rapidity separation between the jets with p_{T} > 35 GeV/c and |y| < 4.7 using the data samples of pp collisions at \sqrt{s} = 2.76 TeV , which were collected by the CMS (Compact Muon Solenoid) detector in 2013. The veto on additional jet activity was imposed in the transverse momentum interval from 20 to 35 GeV/c to improve the sensitivity of the observables. The measurement was compared with DGLAP based Monte-Carlo event generators PYTHIA 8 tune 4C and HERWIG++ tune EE3C. The prediction of PYTHIA 8 demonstrate well agreement with the ratios without the veto, whereas the imposition of the veto reveals some deviation of PYTHIA 8 prediction in the moderate rapidity interval \Delta y = |y_{1} - y_{2}| < 4. The HERWIG++ predictions exceed the measurement in both cases.