Production and decay of D1 (2420)0 and D2∗ (2460)0

Abstract We have investigated D + π − and D ∗+ π − final states and observed the two established L = 1 charmed mesons, the D 1 (2420) 0 with mass 2421 −2−2 +1+2 MeV/ c 2 and width 20 −5−3 +6+3 MeV/ c 2 and the D 2 ∗ (2460) 0 with mass 2465 ± 3 ± 3 MeV/ c 2 and width 28 −7−6 +8+6 MeV/ c 2 . Properties of these final states, including their decay angular distributions and spin-parity assignments, have been studied. We identify these two mesons as the j light = 3 2 doublet predicted by HQET. We also obtain constraints on Γ s / (Γ s + Γ D ) as a function of the cosine of the relative phase of the two amplitudes in the D 1 (2420) 0 decay.