  We have investigated $D^{+}\pi^{-}$ and $D^{*+}\pi^{-}$ final states and
observed the two established $L=1$ charmed mesons, the $D_1(2420)^0$ with mass
$2421^{+1+2}_{-2-2}$ MeV/c$^{2}$ and width $20^{+6+3}_{-5-3}$ MeV/c$^{2}$ and
the $D_2^*(2460)^0$ with mass $2465 \pm 3 \pm 3$ MeV/c$^{2}$ and width
$28^{+8+6}_{-7-6}$ 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 {\footnotesize $\Gamma_S/(\Gamma_S +
\Gamma_D)$} as a function of the cosine of the relative phase of the two
amplitudes in the $D_1(2420)^0$ decay.
