Systematic errors:

See table 2 for a list of systematic errors.

Source	Uncertainty $(\%)$
Initial $\Lambda ^{0}_{b}$ $p_T$ spectrum	7.6
$\Lambda ^{0}_{b}$ polarisation	7.0
$\Lambda ^{0}_{b}$ lifetime	-4.0 +5.0
Initial $\overline{B^{0}}$ $p_T$ spectrum	4.0
Simulation statistics	1.9
$\Lambda ^{+}_{c}$ resonance structure	1.0
proton vs $\pi$ trigger efficiency	0.6
$\Lambda ^{0}_{b}$ background shapes	4.3
$\overline{B^{0}}$ background shapes	0.9
$\Lambda ^{0}_{b}$ width	2.8
$\overline{B^{0}}$ width	1.8
$\Lambda^{0}_{b} \rightarrow \Lambda^{+}_{c} K^{-}$	1.6
Total	+13.6 -13.3

$\parbox{0.9\linewidth}{ \caption{ A sum... ...uncertainty (not including $\Lambda^{+}_{c}$\ branching ratio uncertainty). } }$