is a technical term which is also a compound noun. Ordinary native Japanese speakers usually have no idea about what means, so it's not surprising to me if it is not listed in an accent dictionary.
Anyway, according to online videos (1, 2), the pitch accent of is LHHHHHH. I think you can infer this if you know the pitch accent of and .
Related:
* What are the pitch-accent rules for compound nouns?