{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2002:7SZQ2PWTXDEFIXCU6NO7VTAGMU","short_pith_number":"pith:7SZQ2PWT","schema_version":"1.0","canonical_sha256":"fcb30d3ed3b8c8545c54f35dfacc06650154aa673fc244d948c643a2961c31b6","source":{"kind":"arxiv","id":"astro-ph/0202018","version":1},"attestation_state":"computed","paper":{"title":"The intermediate-age open cluster NGC 2158","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"Giovanni Carraro (Padova), Leo Girardi (Trieste), Paola Marigo (Padova)","submitted_at":"2002-02-01T11:19:39Z","abstract_excerpt":"We report on $UBVRI$ CCD photometry of two overlapping fields in the region of the intermediate-age open cluster NGC 2158 down to V=21. By analyzing Colour-Colour (CC) and Colour-Magnitude Diagrams (CMD) we infer a reddening $E_{B-V}= 0.55\\pm0.10$, a distance of $3600 \\pm 400$ pc, and an age of about 2 Gyr. Synthetic CMDs performed with these parameters (but fixing $E_{B-V}=0.60$ and $[{\\rm Fe/H}]=-0.60$), and including binaries, field contamination, and photometric errors, allow a good description of the observed CMD. The elongated shape of the clump of red giants in the CMD is interpreted as"},"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":"astro-ph/0202018","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"2002-02-01T11:19:39Z","cross_cats_sorted":[],"title_canon_sha256":"f5e9c0c3c749bc31042c418c4c4fcb9f41d3fd77686ae15ac146fc40c33429e1","abstract_canon_sha256":"088f104c1a99f27517b96a0024292106c349f780218e6770d65520eab4836183"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:07:45.128617Z","signature_b64":"0s3zRtNC82MV0UVLEtMjo8Y1XGg8KaZuu8TdkXK9LPFAS75Z2tRoRogj+UJVl223MFn8imOaSJBhcjbb59JXCg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"fcb30d3ed3b8c8545c54f35dfacc06650154aa673fc244d948c643a2961c31b6","last_reissued_at":"2026-05-18T01:07:45.127874Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:07:45.127874Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"The intermediate-age open cluster NGC 2158","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"Giovanni Carraro (Padova), Leo Girardi (Trieste), Paola Marigo (Padova)","submitted_at":"2002-02-01T11:19:39Z","abstract_excerpt":"We report on $UBVRI$ CCD photometry of two overlapping fields in the region of the intermediate-age open cluster NGC 2158 down to V=21. By analyzing Colour-Colour (CC) and Colour-Magnitude Diagrams (CMD) we infer a reddening $E_{B-V}= 0.55\\pm0.10$, a distance of $3600 \\pm 400$ pc, and an age of about 2 Gyr. Synthetic CMDs performed with these parameters (but fixing $E_{B-V}=0.60$ and $[{\\rm Fe/H}]=-0.60$), and including binaries, field contamination, and photometric errors, allow a good description of the observed CMD. The elongated shape of the clump of red giants in the CMD is interpreted as"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0202018","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":"astro-ph/0202018","created_at":"2026-05-18T01:07:45.128004+00:00"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0202018v1","created_at":"2026-05-18T01:07:45.128004+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0202018","created_at":"2026-05-18T01:07:45.128004+00:00"},{"alias_kind":"pith_short_12","alias_value":"7SZQ2PWTXDEF","created_at":"2026-05-18T12:25:50.845339+00:00"},{"alias_kind":"pith_short_16","alias_value":"7SZQ2PWTXDEFIXCU","created_at":"2026-05-18T12:25:50.845339+00:00"},{"alias_kind":"pith_short_8","alias_value":"7SZQ2PWT","created_at":"2026-05-18T12:25:50.845339+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/7SZQ2PWTXDEFIXCU6NO7VTAGMU","json":"https://pith.science/pith/7SZQ2PWTXDEFIXCU6NO7VTAGMU.json","graph_json":"https://pith.science/api/pith-number/7SZQ2PWTXDEFIXCU6NO7VTAGMU/graph.json","events_json":"https://pith.science/api/pith-number/7SZQ2PWTXDEFIXCU6NO7VTAGMU/events.json","paper":"https://pith.science/paper/7SZQ2PWT"},"agent_actions":{"view_html":"https://pith.science/pith/7SZQ2PWTXDEFIXCU6NO7VTAGMU","download_json":"https://pith.science/pith/7SZQ2PWTXDEFIXCU6NO7VTAGMU.json","view_paper":"https://pith.science/paper/7SZQ2PWT","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=astro-ph/0202018&json=true","fetch_graph":"https://pith.science/api/pith-number/7SZQ2PWTXDEFIXCU6NO7VTAGMU/graph.json","fetch_events":"https://pith.science/api/pith-number/7SZQ2PWTXDEFIXCU6NO7VTAGMU/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/7SZQ2PWTXDEFIXCU6NO7VTAGMU/action/timestamp_anchor","attest_storage":"https://pith.science/pith/7SZQ2PWTXDEFIXCU6NO7VTAGMU/action/storage_attestation","attest_author":"https://pith.science/pith/7SZQ2PWTXDEFIXCU6NO7VTAGMU/action/author_attestation","sign_citation":"https://pith.science/pith/7SZQ2PWTXDEFIXCU6NO7VTAGMU/action/citation_signature","submit_replication":"https://pith.science/pith/7SZQ2PWTXDEFIXCU6NO7VTAGMU/action/replication_record"}},"created_at":"2026-05-18T01:07:45.128004+00:00","updated_at":"2026-05-18T01:07:45.128004+00:00"}