The differential branching fraction of the rare decay b0 + is measured as a function of q2, the square of the dimuon invariant mass. The analysis is performed using proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb1, collected by the LHCb experiment. Evidence of signal is observed in the q2 region below the square of the J/ mass. Integrating over 15 < q2 < 20 GeV2/c4 the differential branching fraction is measured asdb0+/dq2=1.180.08+0.09±0.03±0.27×107GeV2/c41, where the uncertainties are statistical, systematic and due to the normalisation mode, b0 J/, respectively. In the q2 intervals where the signal is observed, angular distributions are studied and the forward-backward asymmetries in the dimuon (AFB) and hadron (AFBh) systems are measured for the first time. In the range 15 < q2 < 20 GeV2/c4 they are found to beAFB=0.05±0.09stat±0.03systandAFBh=0.29±0.07stat±0.03syst.
