 Matched expansion with square-root and logarithmic corrections

A decaying algebraic tail in an inner asymptotic expansion can become a fractional-order outer correction after rescaling. For an inner tail proportional to $r^{-1/2}$ and outer variable $x=ϵr$, the outer correction is proportional to ${ϵ}^{1/2}{x}^{-1/2}$. If the next outer correction contains $ϵ\log x$, expressing it in the inner variable produces both $ϵ\log r$ and $ϵ\log ϵ$. Omitting the latter loses a term larger than a plain $O(ϵ)$ correction. Matching must include all these scales and constants, rather than only the leading algebraic powers.