Observation of orbitally excited B mesons in p(p)over-bar collisions at root s=1.8 TeV

Abstract

We measure the relative rate of production of orbitally excited (L=1) states of B mesons (B**) by observing their decays into Bπ±. We reconstruct B mesons through semileptonic decay channels using data collected pp̄ collisions at √s= 1.8 TeV. The fraction of light B mesons that are produced as L= 1B** states is measured to be 0.28±0.06(stat)±0.03(syst). We also measure the collective mass of the B** states, and quantify the result by quoting the (model-dependent) mass of the lowest B** state to be m(B1) = 5.71 ±0.02GeV/c2