radio-rian: a cleaned, controlled-vocabulary, IntCal20-recalibrated corpus of Irish radiocarbon determinations

A curated, calibration-ready dataset of Irish radiocarbon determinations, built on Robert M. Chapple's 2019 Catalogue of Radiocarbon Determinations & Dendrochronology Dates. It adds a controlled site-type vocabulary anchored to the Archaeological Survey of Ireland classification; calibration metadata (material, δ13C, δ15N) recovered from the catalogue's notes and from TII monographs and XRONOS; reservoir classification; IntCal20 recalibration emitting one row per highest-posterior-density interval so multimodality is preserved; cross-validation against the compilation ecosystem (which surfaced transcription errors in the source); and a post-2019 extension harvested from excavations.ie, the Royal Irish Academy C14 Dates Scheme, and TII Heritage road-scheme monographs. The cleaning decisions are the contribution and every one is recorded and reviewable. This is a 0.9 release. The raw determinations, checksums, and IntCal20 calibration are final; the site-type vocabulary, the material and reliability inference, and the reservoir classification are machine-generated first passes (decided_by=rule) awaiting line-by-line human review. A 1.0 release follows that review.