  We study the lifetime of a Bose gas at and around unitarity using a Feshbach
resonance in lithium~7. At unitarity, we measure the temperature dependence of
the three-body decay coefficient $L_{3}$. Our data follow a $L_3 {=}
\lambda_{3} / T^{2}$ law with $\lambda_{3} = 2.5(3)_{stat}_(6)_{sys} 10^{-20}
(\mu K)^2 cm^6 s^{-1}$ and are in good agreement with our analytical result
based on the zero-range theory. Varying the scattering length $a$ at fixed
temperature, we investigate the crossover between the finite-temperature
unitary region and the previously studied regime where $|a|$ is smaller than
the thermal wavelength. We find that $L_{3}$ is continuous across resonance,
and over the whole $a {<} 0$ range our data quantitatively agree with our
calculation.
