17% of the $(4\pi)^-$ final state. All of the $\omega\pi^-$ final state is consistent with coming from $A^-$ decay.

Observation of ${B}^-\to D^{*o}\pi^+\pi^-\pi^-\pi^o$ {#sec:Ds04pi}
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We proceed in the same manner as for the $\overline{B}^o$ reaction with the exception that we use the $D^{*o}\to \pi^o D^o$ decay mode and restrict ourselves to the $D^o\to K^-\pi^+$ decay mode only due to large backgrounds in the other modes. The $\chi^2$ is calculated according to equation \[eq:chisq\] and we use a cut value of 8. The $M_B$ distributions for $\Delta E$ sidebands and signal data are shown in Fig. \[bm\_4pi\_0kpi\] for the $D^o\to K^-\pi^+$ decay mode. We see a signal of 195$\pm$26 events yielding a branching fraction of $${\cal{B}}({B}^-\to D^{*o}\pi^+\pi^-\pi^-\pi^o) = (1.80\pm 0.24\pm 
0.25) \%~~~~.$$

The $\pi^+\pi^-\pi^o$ mass spectrum shown in Fig. \[m3pi\_c\_0kpi\] shows the presence of an $\omega$.

Selecting on the presence of an $\omega$ with $r<0.7$ we show the sideband and signal plots in Fig. \[bm\_4pi\_0kpi\_4\]. (Here we do not use the previously defined $\chi^2$ cut.)

The branching ratio is $${\cal{B}}({B}^-\to D^{*o}\omega\pi^-) = (0.45\pm 0.10 \pm 0.07) 
\%~~~~.$$

In Fig. \[m4pi\_c4\_0kpi\] we show the $\omega\pi^-$ mass spectrum. We see an enhancement at around 1.4 GeV as in the neutral $B$ case. 