Euler charcteristic of the intersection of hyperplanes with a pointed cone

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Consider a pointed closed convex polyhedral cone $C$ in $\mathbb R^n$.

Let $S_1,..,S_n$ be hyperplanes in $\mathbb R^n$.

Consider $S=C \cap \left(\bigcap\limits_{i=1}^n S_i\right)$.

If $S$ is compact and nonempty, is it true that the Euler charcteristic is equal to 1?

In the simple case of $C$ being the positive orthant with one hyperplane given by $\sum_{i=1}^n x_i = 1$, I know that the answer is affirmative since $S$ will simply be a simplex.

If the claim is true in general or for some special case, please provide me a reference that states this.

Thank you.


Edit: To have some meaningful sub-example,

Consider $C$ to be the closed positive orthant

Let $S_1$ be given by $\sum_{i=1}^n \alpha_i x_i = M_1$

$S_2$ be given by $\sum_{i=1}^n \beta_i x_i = M_2$, where $\alpha_i,\beta_i\ge 0, M_1,M_2 >0$.

Is it true in this case?

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The intersection of finitely many affine hyperplanes in $\mathbb R^n$ is a proper affine subspace $U\subseteq \mathbb R^n$. So you can describe $S$ equivalently as $C\cap U$, where $C$ is a pointed closed convex polyhedral cone and $U$ a proper affine subspace. The intersection of a polyhedral cone with an affine subspace is either empty or a polyhedron. In the non-empty case you have $\chi(S)=1$ since polyhedra are contractible.