{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2021:7XAYNYALH4QISURXMV5GRCK6GF","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"38802c03f3ff3c28932961d91847657444cdd59528d8aaccd180d01de837a527","cross_cats_sorted":["physics.ins-det"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.IM","submitted_at":"2021-08-17T09:13:39Z","title_canon_sha256":"0d459f4d362560e445cf3e26c47213ad9f864c4b75a77fd672a9edfb78c4117b"},"schema_version":"1.0","source":{"id":"2108.07526","kind":"arxiv","version":4}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2108.07526","created_at":"2026-07-05T04:29:08Z"},{"alias_kind":"arxiv_version","alias_value":"2108.07526v4","created_at":"2026-07-05T04:29:08Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2108.07526","created_at":"2026-07-05T04:29:08Z"},{"alias_kind":"pith_short_12","alias_value":"7XAYNYALH4QI","created_at":"2026-07-05T04:29:08Z"},{"alias_kind":"pith_short_16","alias_value":"7XAYNYALH4QISURX","created_at":"2026-07-05T04:29:08Z"},{"alias_kind":"pith_short_8","alias_value":"7XAYNYAL","created_at":"2026-07-05T04:29:08Z"}],"graph_snapshots":[{"event_id":"sha256:067c36a55e371b81120f512293864c7f535b05bd851f4f3b64c789594fe9c5b1","target":"graph","created_at":"2026-07-05T04:29:08Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2108.07526/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Very little work has been done searching for astrophysical transient optical emission in the millisecond to nanosecond regime with significant sensitivity. We call this regime \"Ultra-Fast Astronomy\", or UFA. To investigate transients on as short time scales as possible, we developed our own customized readout system for a silicon photomultiplier (SiPM)-based UFA camera, intended for use on conventional astronomical telescopes. SiPMs, available in array packages for imaging a field, are capable of time-tagged single-photon detection in the visible wavelength range. Our readout system consists o","authors_text":"Albert Wai Kit Lau, Bruce Grossan, George F. Smoot, Mehdi Shafiee, Yan Yan Chan","cross_cats":["physics.ins-det"],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.IM","submitted_at":"2021-08-17T09:13:39Z","title":"A SiPM photon-counting readout system for Ultra-Fast Astronomy"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2108.07526","kind":"arxiv","version":4},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:57ad4b129ba69865c7ff1de7c62c2de22a6ecd75a2df84cff85ceebcbc9ba502","target":"record","created_at":"2026-07-05T04:29:08Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"38802c03f3ff3c28932961d91847657444cdd59528d8aaccd180d01de837a527","cross_cats_sorted":["physics.ins-det"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.IM","submitted_at":"2021-08-17T09:13:39Z","title_canon_sha256":"0d459f4d362560e445cf3e26c47213ad9f864c4b75a77fd672a9edfb78c4117b"},"schema_version":"1.0","source":{"id":"2108.07526","kind":"arxiv","version":4}},"canonical_sha256":"fdc186e00b3f20895237657a68895e31775f0b2377b72d3a052ba3c7d30ac9eb","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"fdc186e00b3f20895237657a68895e31775f0b2377b72d3a052ba3c7d30ac9eb","first_computed_at":"2026-07-05T04:29:08.873412Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T04:29:08.873412Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"saee78GS1JVO8BcOfu2K3Uo9x4EuRAHdk/dHdDtTXDWueJ403KpZ+hLGYSD2xTFUqhQzjh7ho6EAsUhDtTeZCA==","signature_status":"signed_v1","signed_at":"2026-07-05T04:29:08.876619Z","signed_message":"canonical_sha256_bytes"},"source_id":"2108.07526","source_kind":"arxiv","source_version":4}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:57ad4b129ba69865c7ff1de7c62c2de22a6ecd75a2df84cff85ceebcbc9ba502","sha256:067c36a55e371b81120f512293864c7f535b05bd851f4f3b64c789594fe9c5b1"],"state_sha256":"3591cf95fb5a53f22012ec9cdbea6b0c79ec47c78800c602c1db9d9dd2a93de7"}