@article{da2f45814c214ab1ac5a69d6fe246372, title = "First observations of the rare decays B (+) -> K (+)pi (+)pi (-)mu(+)mu (-) and B (+)-> phi K (+)mu(+)mu (-)", abstract = "First observations of the rare decays B (+) -> K (+)pi (+) pi (-) mu (+) mu (-) and B (+)-> phi K+ mu(+)mu(-) are presented using data corresponding to an integrated luminosity of 3.0 fb(-1), collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. The branching fractions of the decays areB(B (+) -> K (+)pi (+) pi (-) mu (+) mu (-) ) = (4.36 (-0.27) (+0.29) (stat) +/- 0.21 (syst) +/- (norm)) x 10(-7), B(B (+)-> phi K+ mu(+)mu(-)) = (0.82 (+0.19)(-0.17) (stat) (+0.10)(-0.04) (syst) +/- 0.27 (norm)) x 10(-7) where the uncertainties are statistical, systematic, and due to the uncertainty on the branching fractions of the normalisation modes. A measurement of the differential branching fraction in bins of the invariant mass squared of the dimuon system is also presented for the decay B (+) -> K (+)pi (+) pi (-) mu (+) mu (-)", keywords = "Rare decay, Hadron-Hadron Scattering, B physics, Flavor physics, AXIAL-VECTOR, MESONS, TOOL", author = "R. Aaij and B. Adeva and M. Adinolfi and A. Affolder and Z. Ajaltouni and S. Akar and J. Albrecht and F. Alessio and M. Alexander and S. Ali and G. Alkhazov and {Alvarez Cartelle}, P. and Alves, {A. A.} and S. Amato and S. Amerio and Y. Amhis and L. An and L. Anderlini and J. Anderson and R. Andreassen and M. Andreotti and Andrews, {J. E.} and Appleby, {R. B.} and Gutierrez, {O. Aquines} and F. Archilli and A. Artamonov and M. Artuso and E. Aslanides and G. Auriemma and M. Baalouch and S. Bachmann and Back, {J. J.} and A. Badalov and W. Baldini and Barlow, {R. J.} and C. Barschel and S. Barsuk and W. Barter and V. Batozskaya and V. Battista and A. Bay and Laurence Carson and Clarke, {P. E. L.} and Cowan, {G. A.} and Daniel Craik and S. Eisenhardt and Silvia Gambetta and F. Muheim and M. Needham and S. Playfer and {LHCb Collaboration}", year = "2014", month = oct, day = "9", doi = "10.1007/JHEP10(2014)064", language = "English", volume = "1410", journal = " Journal of High Energy Physics", issn = "1126-6708", publisher = "Springer-Verlag", number = "10", }