missing intent concept?

I am working on a MathCAT issue about bra-ket notation. Much to my
surprise, I didn't find it listed in either the core
<https://w3c.github.io/mathml-docs/intent-core-concepts/>or open
<https://w3c.github.io/mathml-docs/intent-open-concepts/>concept lists.
Does it have some other name, or was it overlooked?

    Neil