We measure the masses, decay widths and relative production rate of orbital
ly excited B mesons using 1.25 million hadronic Z decays recorded by the L3
detector. B-meson candidates are inclusively reconstructed and combined wi
th charged pions produced at the primary event Vertex. An excess of events
above the expected background in the Err mass spectrum in the region 5.6-5.
8 GeV is interpreted as resulting from the decay B-u,B-d** --> B-pi((*)), w
here B-u,B-d** denotes a mixture of l = 1 B-meson states containing a u or
a d quark. A fit to the mass spectrum yields the masses and decay widths of
the B-1* and B-2* spin states, as well as the branching fraction for the c
ombination of l = 1 states. In addition, evidence is presented for the exis
tence of an excited B-meson state or mixture of states in the region 5.9-6.
0 GeV. (C) 1999 Published by Elsevier Science B.V. All rights reserved.