Let K$K$ be an imaginary quadratic number field with p$p$-Sylow-class group A(K)$A(K)$ and L/K$L/K$ be an unramified cyclic extension of K$K$ of degree p$p$ (p$p$ prime). Then I am looking for heuristics on
Ker(N_{L/K}:A(L)\rightarrow A(K)), where
$ker(N_{L/K}:A(L)\rightarrow A(K))$,
where $N_{L/K}$ is the usual norm map on ideal classes. Numerical data suggest that:
$|KerN_{L/K}|\le p^2$ with high probability. But that is rather unprecise. Are there any more satisfactory known results ?
There is a result by Wittmann who gives some heuristics for cyclic p$p$-extensions of $\mathbb{Q}$ and I wonder if one can possibly generalize his ideas to the above scenario.