Measurement of the fragmentation fraction ratio f s /f d and its dependence on B meson kinematics

R. Aaij, C. Abellan Beteta, A. Adametz, B. Adeva, M. Adinolfi, C. Adrover, A. Affolder, Z. Ajaltouni, J. Albrecht, F. Alessio, M. Alexander, S. Ali (+614 others)
2013 Journal of High Energy Physics  
The relative production rate of B^0_s and B^0 mesons is determined with the hadronic decays B^0_s→ D^-_sπ^+ and B^0 → D^-K^+. The measurement uses data corresponding to 1.0 fb^-1 of pp collisions at a centre-of-mass energy of √(s)=7 TeV recorded in the forward region with the LHCb experiment. The ratio of production rates, f_s/f_d, is measured to be 0.238 ± 0.004 ± 0.015 ± 0.021 , where the first uncertainty is statistical, the second systematic, and the third theoretical. This is combined with
more » ... is is combined with a previous LHCb measurement to obtain f_s/f_d = 0.256 ± 0.020. The dependence of f_s/f_d on the transverse momentum and pseudorapidity of the B meson is determined using the decays B^0_s→ D^-_sπ^+ and B^0→ D^-π^+. There is evidence for a decrease with increasing transverse momentum, whereas the ratio remains constant as a function of pseudorapidity. In addition, the ratio of branching fractions of the decays B^0→ D^-K^+ and B^0→ D^-π^+ is measured to be 0.0822 ± 0.0011 (stat) ± 0.0025 (syst).
doi:10.1007/jhep04(2013)001 fatcat:isxg2z2lwnabtkt5o4tebybcgi