B -meson production at forward and backward rapidity in p+p and Cu + Au collisions at sNN =200 GeV

The fraction of J/psi mesons which come from B-meson decay, F-B -> J/psi is measured for J/psi rapidity 1.2 < |y| < 2.2 and p(T) > 0 in p + p and Cu+Au collisions at root s(NN) = 200 GeV with the PHENIX detector. The extracted fraction is F-B -> J/psi = 0.025 +/- 0.006 (stat) +/- 0.010(syst) for p + p collisions. For Cu+Au collisions, F-B -> J/psi is 0.094 +/- 0.028(stat) +/- 0.037(syst) in the Au-going direction (-2.2 < y < -1.2) and 0.089 +/- 0.026(stat) +/- 0.040(syst) in the Cu-going direction (1.2 < y < 2.2). The nuclear modification factor, R-CuAu,of B mesons in Cu+Au collisions is consistent with binary scaling of measured yields in p + p at both forward and backward rapidity.