Abstract
We refine a recent result on the structure of measures satisfying a linear partial differential equation 𝓐μ = σ, μ, σ are Radon measures, considering the measure μ(x) = g(x)d
x + μus
(x̃)(μs
(x̄) + d
x̄) where x = (x̃,x̄) ∈ ℝ
k
× ℝ
d−k
, μus
is a uniformly singular measure in x̃
0 and the measure μs
is a singular measure. We proved that for μus
-a.e. x̃
0 the range of the Radon-Nykodim derivative
f
~
(
x
~
0
)
=
d
μ
u
s
d
|
μ
u
s
|
(
x
~
0
)
$\begin{array}{}
\tilde{f}(\tilde{{\bf x}}_0) = \frac{d \mu_{us}}{d | \mu_{us}|}(\tilde{{\bf x}}_0)
\end{array}$
is in the set ∩
ξ̃
∈P̃
𝓚er
A
P̃
(
ξ
) and, if μs
is different to zero, for μs
-a.e. x̄
0 the range of the Radon-Nykodim derivative
f
¯
(
x
¯
0
)
=
d
μ
s
d
|
μ
s
|
(
x
¯
0
)
$\begin{array}{}
\bar{f}(\bar{{\bf x}}_0) = \frac{d \mu_{s}}{d | \mu_{s}|}(\bar{{\bf x}}_0)
\end{array}$
is in the set ∪
ξ̄
∈P̄
𝓚er
A
P̄
(
ξ
) where P̃ × P̄ = P is a manifold determined by the main symbol A
P
= A
P̃
⋅ A
P̄
of the operator 𝓐.