{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2013:N6HJJ73TYPIKLAJGEZ5CF6ZZI7","short_pith_number":"pith:N6HJJ73T","schema_version":"1.0","canonical_sha256":"6f8e94ff73c3d0a58126267a22fb3947c81f327f03504728cc987d40872e7e5b","source":{"kind":"arxiv","id":"1307.2629","version":1},"attestation_state":"computed","paper":{"title":"The Parkes Pulsar Timing Array","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.HE","astro-ph.SR"],"primary_cat":"astro-ph.IM","authors_text":"G. Hobbs","submitted_at":"2013-07-09T23:51:48Z","abstract_excerpt":"The aims of the Parkes Pulsar Timing Array (PPTA) project are to 1) make a direct detection of gravitational waves, 2) improve the solar system planetary ephemeris and 3) develop a pulsar-based time scale. In this article we describe the project, explain how the data are collected and processed and describe current research. Our current data sets are able to place an upper bound on the gravitational wave background that is the most stringent to date."},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"1307.2629","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2013-07-09T23:51:48Z","cross_cats_sorted":["astro-ph.HE","astro-ph.SR"],"title_canon_sha256":"916d16420edf06db9bff0ae3e62e9b6b2ea64beffc349ec00f32660f57877357","abstract_canon_sha256":"06298ef309327117b0261492e958dea2946dd5c63ed16593b916a8f6a18bd9eb"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:48:52.588045Z","signature_b64":"J+oIU+BMBhRFLJmErZoB7jbvc5XAvLYyG+AJ9KSBoNs9P5PjbzO9Psu4fn6rcYPdmCbS79E7Rw93976VaLIUAg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"6f8e94ff73c3d0a58126267a22fb3947c81f327f03504728cc987d40872e7e5b","last_reissued_at":"2026-05-18T01:48:52.587478Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:48:52.587478Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"The Parkes Pulsar Timing Array","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.HE","astro-ph.SR"],"primary_cat":"astro-ph.IM","authors_text":"G. Hobbs","submitted_at":"2013-07-09T23:51:48Z","abstract_excerpt":"The aims of the Parkes Pulsar Timing Array (PPTA) project are to 1) make a direct detection of gravitational waves, 2) improve the solar system planetary ephemeris and 3) develop a pulsar-based time scale. In this article we describe the project, explain how the data are collected and processed and describe current research. Our current data sets are able to place an upper bound on the gravitational wave background that is the most stringent to date."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1307.2629","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"aliases":[{"alias_kind":"arxiv","alias_value":"1307.2629","created_at":"2026-05-18T01:48:52.587565+00:00"},{"alias_kind":"arxiv_version","alias_value":"1307.2629v1","created_at":"2026-05-18T01:48:52.587565+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1307.2629","created_at":"2026-05-18T01:48:52.587565+00:00"},{"alias_kind":"pith_short_12","alias_value":"N6HJJ73TYPIK","created_at":"2026-05-18T12:27:52.871228+00:00"},{"alias_kind":"pith_short_16","alias_value":"N6HJJ73TYPIKLAJG","created_at":"2026-05-18T12:27:52.871228+00:00"},{"alias_kind":"pith_short_8","alias_value":"N6HJJ73T","created_at":"2026-05-18T12:27:52.871228+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":2,"internal_anchor_count":2,"sample":[{"citing_arxiv_id":"2606.05343","citing_title":"Constraining Orbital Eccentricity of a Supermassive Black Hole Binary Candidate PKS 2131-0211","ref_index":106,"is_internal_anchor":true},{"citing_arxiv_id":"2203.06142","citing_title":"Cosmology Intertwined: A Review of the Particle Physics, Astrophysics, and Cosmology Associated with the Cosmological Tensions and Anomalies","ref_index":160,"is_internal_anchor":true}]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/N6HJJ73TYPIKLAJGEZ5CF6ZZI7","json":"https://pith.science/pith/N6HJJ73TYPIKLAJGEZ5CF6ZZI7.json","graph_json":"https://pith.science/api/pith-number/N6HJJ73TYPIKLAJGEZ5CF6ZZI7/graph.json","events_json":"https://pith.science/api/pith-number/N6HJJ73TYPIKLAJGEZ5CF6ZZI7/events.json","paper":"https://pith.science/paper/N6HJJ73T"},"agent_actions":{"view_html":"https://pith.science/pith/N6HJJ73TYPIKLAJGEZ5CF6ZZI7","download_json":"https://pith.science/pith/N6HJJ73TYPIKLAJGEZ5CF6ZZI7.json","view_paper":"https://pith.science/paper/N6HJJ73T","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1307.2629&json=true","fetch_graph":"https://pith.science/api/pith-number/N6HJJ73TYPIKLAJGEZ5CF6ZZI7/graph.json","fetch_events":"https://pith.science/api/pith-number/N6HJJ73TYPIKLAJGEZ5CF6ZZI7/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/N6HJJ73TYPIKLAJGEZ5CF6ZZI7/action/timestamp_anchor","attest_storage":"https://pith.science/pith/N6HJJ73TYPIKLAJGEZ5CF6ZZI7/action/storage_attestation","attest_author":"https://pith.science/pith/N6HJJ73TYPIKLAJGEZ5CF6ZZI7/action/author_attestation","sign_citation":"https://pith.science/pith/N6HJJ73TYPIKLAJGEZ5CF6ZZI7/action/citation_signature","submit_replication":"https://pith.science/pith/N6HJJ73TYPIKLAJGEZ5CF6ZZI7/action/replication_record"}},"created_at":"2026-05-18T01:48:52.587565+00:00","updated_at":"2026-05-18T01:48:52.587565+00:00"}