Discrete tomography: Magic numbers for $N$-fold symmetry

We consider the problem of distinguishing convex subsets of $n$-cyclotomic model sets $varLambda$ by (discrete parallel) X-rays in prescribed $varLambda$-directions. In this context, a `magic number $m_{varLambda}$ has the property that any two convex subsets of $varLambda$ can be distinguished by their X-rays in any set of $m_{varLambda}$ prescribed $varLambda$-directions. Recent calculations suggest that (with one exception in the case $n=4$) the least possible magic number for $n$-cyclotomic model sets might just be $N+1$, where $N=operatorname{lcm}(n,2)$.