The coordinate-momentum double distribution function $\rho ({ \bf r}, { \bf p}) d^{ 3}rd^{ 3}p$ is calculated in the local density approximation for bosons with positive scattering length $a$ in a trap. The calculation is valid to the first order of $a$. To clarify the meaning of the result, it is compared for a special case with the double distribution function $\rho_{ w}d^{ 3} rd^{ 3}p$ of Wigner.
Categories: cond-mat