The paper deals with the spectral structure of the operator H = -▽·b▽ in R~n where & is a stratified matrix-valued function. Using a partial Fourier transform, it is represented as a direct integral of a family of ordinary differential operators H_p, p ∈ R~n. Every operator Hp has two thresholds and the kernels are studied in their (spectral) neighborhoods, uniformly in compact sets of p. As in [3], such estimates lead to a limiting absorption principle for H. Furthermore, estimates of the resolvent of H near the bottom of its sped rum (''low energy" estimates) are obtained.
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