Associated production of electroweak bosons and heavy mesons at LHCb and   prospects to observe double parton interactions
  The production of weak gauge bosons in association with heavy flavored mesons at the LHCb conditions is considered, and a detailed study of the different contributing processes is presented including single (SPS) and double (DPS) parton scattering mechanisms. We find that the usual DPS factorization formula needs to be corrected for the limited partonic phase space, and that including the relevant corrections reduces discrepancies in the associated $ZD$ production. We conclude finally that double parton scattering dominates the production of same-sign $W^\pm D^\pm$ states, as well as the production of $W^-$ bosons associated with $B$-mesons. The latter processes can thus be regarded as new useful DPS indicators. 
S.P. Baranov, A.V. Lipatov, M.A. Malyshev, A.M. Snigirev, N.P. Zotov
hep-ph