Boost Asymmetry of the diboson productions in pp collisions

We propose the boost asymmetry of the diboson productions qiq¯j→VV′ in pp collisions (VV′=Wγ, W+W−, and WZ) as a new experimental observable, which can provide unique information on the proton structure. The boost asymmetry rises as the difference in the kinematics of the two bosons, that are coupled to the two different quark and antiquark initial states, respectively, and thus reflects different features of the qi and q¯j parton densities. By comparing the kinematics of the two bosons, such as the boson energy or rapidity, the diboson events with q¯j having higher energy than qi can be distinguished from those with qi having higher energy than q¯j. This would provide unique information in some special parton momentum fraction regions, which cannot be directly proved by current W and Z measurements at the Large Hadron Collider or other deep inelastic scattering experiments.