The paper this is based on: https://eprint.iacr.org/2021/350.pdf
Actually really interesting. Not quite like just a "AND of sigma protocols" in which you share a hash challenge across multiple assertions, but a randomized linear combination of sigma protocols (forcing unpredictable weightings for each of the signatures), and outputting (R_1..R_n, S_agg). At least that's my at-first-skim sense of it. That's pretty powerful, and I'm not surprised they have a decent security proof for it.
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