Add this internationally authored preprint which came out just this past week. There were indications of 14C excursions from ice core 10Be and 35Cl, and archeology, but while the resolution there was too broad to positively identify, they provided the researchers with the zone to search. Decadal dating on tree rings is pretty routine given the expense, but here they dated annually and identified two solar proton events which are much further back than any other secure candidates in the record.
Tree rings reveal two strong solar proton events in 7176 and 5259 BCE
The 7176 BCE synchronization ties together Austrian Larch, German Oak, and California Bristlecone dendrochronologies, verifies the ice core signals which sparked the search, and validates the robustness of the 14C calibration curve. I expect more confirmations of these events will be added.
“False rings” have been the standard but nonsensical YEC rebuttal to the tree ring record, and here suffers another blow. It is not plausible that dendrochronologies which have no geographic or species relationship would be distorted by false rings and remain synchronized over a span of over 9,000 years. That is double the distance in the past as allowed for Noah’s flood by AiG, CMI, ICR, and company. Be prepared for deafening silence.