We shall furnish an asymptotic description of the spectrum of a C-0-semigro
up generator arising in non-isothermal elongational flow. It will be shown
that the spectrum coincides asymptotically with isolated eigenvalues lined
up along a logarithmic curve. The strategy for this result is based on deli
cate asymptotic estimates and ideas developed for the isothermal regime. Th
ese estimates can be successfully employed only since the spectral mapping
theorem is valid for the semigroup. (C) 2000 Academic Press.