{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2023:XKALZ4ESTEGQX2NH6D7OJ5HM3Z","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":"f40cf61bc7bc72184736793bf490ea9cad341fa6f7240bf4a3b6caf47c3c858d","cross_cats_sorted":["astro-ph.IM","gr-qc"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.HE","submitted_at":"2023-06-28T13:51:11Z","title_canon_sha256":"633ef9082526cd8cd4ddfa2dc2d0f430eaf03ed34eee8b89471b92d28d680d86"},"schema_version":"1.0","source":{"id":"2306.16223","kind":"arxiv","version":3}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2306.16223","created_at":"2026-07-05T11:01:54Z"},{"alias_kind":"arxiv_version","alias_value":"2306.16223v3","created_at":"2026-07-05T11:01:54Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2306.16223","created_at":"2026-07-05T11:01:54Z"},{"alias_kind":"pith_short_12","alias_value":"XKALZ4ESTEGQ","created_at":"2026-07-05T11:01:54Z"},{"alias_kind":"pith_short_16","alias_value":"XKALZ4ESTEGQX2NH","created_at":"2026-07-05T11:01:54Z"},{"alias_kind":"pith_short_8","alias_value":"XKALZ4ES","created_at":"2026-07-05T11:01:54Z"}],"graph_snapshots":[{"event_id":"sha256:5529e27e57f48b2f27f576a0ee4eabea7423e166b8f0c02fa7be82f8f2b43178","target":"graph","created_at":"2026-07-05T11:01:54Z","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/2306.16223/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Pulsar timing arrays (PTAs) use an array of millisecond pulsars to search for gravitational waves in the nanohertz regime in pulse time of arrival data. This paper presents rigorous tests of PTA methods, examining their consistency across the relevant parameter space. We discuss updates to the 15-year isotropic gravitational-wave background analyses and their corresponding code representations. Descriptions of the internal structure of the flagship algorithms Enterprise and PTMCMCSampler are given to facilitate understanding of the PTA likelihood structure, how models are built, and what metho","authors_text":"Aaron D. Johnson, Abhimanyu Susobhanan, Adam Brazier, Akash Anumarlapudi, Alexander McEwen, Andrea Mitridate, Andrew R. Kaiser, Anne M. Archibald, Ann Schmiedekamp, Bence B\\'ecsy, Benetge B. P. Perera, Bradley W. Meyers, Brendan Drachler, Brent J. Shapiro-Albert, Caitlin A. Witt, Caner Unal, Carl Schmiedekamp, Cherry Ng, Chiara M. F. Mingarelli, Chung-Pei Ma, Daniel R. Stinebring, David J. Nice, David L. Kaplan, Deborah C. Good, Duncan R. Lorimer, Dustin R. Madison, Elizabeth C. Ferrara, Emmanuel Fonseca, Fronefield Crawford, Gabriel E. Freedman, Gabriella Agazie, Haley M. Wahl, Henri A. Radovan, H. Thankful Cromartie, Ingrid H. Stairs, Jacob E. Turner, James M. Cordes, James W. McKee, J. Andrew Casey-Clyde, Jeffrey S. Hazboun, Joey S. Key, Joseph D. Romano, Joseph Glaser, Joseph K. Swiggum, Joseph Simon, Justin A. Ellis, Kai Schmitz, Katerina Chatziioannou, Kathryn Crowter, Kayhan G\\\"ultekin, Ken D. Olum, Kevin Stovall, Laura Blecha, Luke Zoltan Kelley, Magdalena S. Siwek, Maria Charisi, Matthew Kerr, Maura A. McLaughlin, Megan E. DeCesar, Megan L. Jones, Michael T. Lam, Michele Vallisneri, Natalia Lewandowska, Natasha McMann, Nate Garver-Daniels, Neil J. Cornish, Nihan S. Pol, Nima Laal, Olivia Young (for the NANOGrav Collaboration), Patrick M. Meyers, Paul B. Demorest, Paul R. Brook, Paul S. Ray, Paul T. Baker, Peter A. Gentile, Ross J. Jennings, Rutger van Haasteren, Ryan S. Lynch, Sarah Burke-Spolaor, Sarah J. Vigeland, Scott M. Ransom, Shami Chatterjee, Shashwat C. Sardesai, Sophie Hourihane, Stella Koch Ocker, Stephen R. Taylor, Timothy Dolch, Timothy T. Pennucci, Tingting Liu, T. Joseph W. Lazio, Tyler Cohen, Tyson B. Littenberg, William Fiore, William G. Lamb, Xavier Siemens, Zaven Arzoumanian","cross_cats":["astro-ph.IM","gr-qc"],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.HE","submitted_at":"2023-06-28T13:51:11Z","title":"The NANOGrav 15-year Gravitational-Wave Background Methods"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2306.16223","kind":"arxiv","version":3},"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":"sha256:492eac5fd75487b831bec9240eb433d426c90813d4cf6c5fe3c7f88b1162ce9f","target":"record","created_at":"2026-07-05T11:01:54Z","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":"f40cf61bc7bc72184736793bf490ea9cad341fa6f7240bf4a3b6caf47c3c858d","cross_cats_sorted":["astro-ph.IM","gr-qc"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.HE","submitted_at":"2023-06-28T13:51:11Z","title_canon_sha256":"633ef9082526cd8cd4ddfa2dc2d0f430eaf03ed34eee8b89471b92d28d680d86"},"schema_version":"1.0","source":{"id":"2306.16223","kind":"arxiv","version":3}},"canonical_sha256":"ba80bcf092990d0be9a7f0fee4f4ecde4cb93854e61831fb475b38557d8c00e1","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"ba80bcf092990d0be9a7f0fee4f4ecde4cb93854e61831fb475b38557d8c00e1","first_computed_at":"2026-07-05T11:01:54.222012Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T11:01:54.222012Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"XUaIIi51n0cCVnshV4zDDwyyiXLUvsm8KriKdDw2BApwCg0YaED8KnnkvpqO4hug1RQIQglja7+0M+M9tw/2AA==","signature_status":"signed_v1","signed_at":"2026-07-05T11:01:54.222528Z","signed_message":"canonical_sha256_bytes"},"source_id":"2306.16223","source_kind":"arxiv","source_version":3}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:492eac5fd75487b831bec9240eb433d426c90813d4cf6c5fe3c7f88b1162ce9f","sha256:5529e27e57f48b2f27f576a0ee4eabea7423e166b8f0c02fa7be82f8f2b43178"],"state_sha256":"606f5b3c338692542c3f31a61ba05bd49b0bd97a9db8068630fbfd1754af2dbc"}