{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2015:GKRSQV6IIGIS5VA2HXRRIT7SZG","short_pith_number":"pith:GKRSQV6I","canonical_record":{"source":{"id":"1508.05070","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-08-20T18:51:41Z","cross_cats_sorted":[],"title_canon_sha256":"85347d837e59e8dd57808bbce06f97a8b44e4208147d756ae8353d65af51d27a","abstract_canon_sha256":"7d30a1ea899784af7b57ecfda53026461696e572f072bfd2174caab5816527dc"},"schema_version":"1.0"},"canonical_sha256":"32a32857c841912ed41a3de3144ff2c9975bc29bf0b6a59d7d2afb080611ab08","source":{"kind":"arxiv","id":"1508.05070","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1508.05070","created_at":"2026-05-18T01:32:59Z"},{"alias_kind":"arxiv_version","alias_value":"1508.05070v1","created_at":"2026-05-18T01:32:59Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1508.05070","created_at":"2026-05-18T01:32:59Z"},{"alias_kind":"pith_short_12","alias_value":"GKRSQV6IIGIS","created_at":"2026-05-18T12:29:22Z"},{"alias_kind":"pith_short_16","alias_value":"GKRSQV6IIGIS5VA2","created_at":"2026-05-18T12:29:22Z"},{"alias_kind":"pith_short_8","alias_value":"GKRSQV6I","created_at":"2026-05-18T12:29:22Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2015:GKRSQV6IIGIS5VA2HXRRIT7SZG","target":"record","payload":{"canonical_record":{"source":{"id":"1508.05070","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-08-20T18:51:41Z","cross_cats_sorted":[],"title_canon_sha256":"85347d837e59e8dd57808bbce06f97a8b44e4208147d756ae8353d65af51d27a","abstract_canon_sha256":"7d30a1ea899784af7b57ecfda53026461696e572f072bfd2174caab5816527dc"},"schema_version":"1.0"},"canonical_sha256":"32a32857c841912ed41a3de3144ff2c9975bc29bf0b6a59d7d2afb080611ab08","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:32:59.141644Z","signature_b64":"ETxq3W6h+euVEFRgulXS8WxUvvXdfUppF0TmQLjmXDf1B2n46pVV6pYJRX1jelLH3lLRCpmCqi8KT6hjP2PdCg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"32a32857c841912ed41a3de3144ff2c9975bc29bf0b6a59d7d2afb080611ab08","last_reissued_at":"2026-05-18T01:32:59.141154Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:32:59.141154Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1508.05070","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:32:59Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"62UPVvzIQtO97+yJUVjLpLmIS8QydXmALW9HArliq5sqe51mWyUBIKQ54LxydvXbnItbJIy0+rBi6DGxcAfzCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-27T02:18:00.713301Z"},"content_sha256":"85b7decdfa5370ef4ae5e6197210ecb9c63afeaf352cd5256bac70ab6b4b18c8","schema_version":"1.0","event_id":"sha256:85b7decdfa5370ef4ae5e6197210ecb9c63afeaf352cd5256bac70ab6b4b18c8"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2015:GKRSQV6IIGIS5VA2HXRRIT7SZG","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"NGC 6845: metallicity gradients and star formation in a complex compact group","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"C. Mendes de Oliveira, D. F. de Mello, D. Olave-Rojas, E. R. Carrasco, S. Scarano Jr, S. Torres-Flores","submitted_at":"2015-08-20T18:51:41Z","abstract_excerpt":"We have obtained Gemini/GMOS spectra of 28 regions located across the interacting group NGC 6845, spanning from the inner regions of the four major galaxies (NGC 6845A, B, C, D) to the tidal tails of NGC 6845A. All regions in the tails are star-forming objects with ages younger than 10 Myr. We derived the gas-phase metallicity gradients across NGC 6845A and its two tails and we find that these are shallower than those for isolated galaxies. NGC 6845A has a gas-phase oxygen central metallicity of \\mbox{12+log(O/H)$\\sim$8.5} and a flat gas-phase metallicity gradient ($\\beta$=0.002$\\pm$0.004 dex "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1508.05070","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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:32:59Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"g2oxuoMSD2+vCzkgs8THWw2iAuSN2uf6ZGmobMBKS5RsuXaSPx1uybudzwVW5NbeMtLRXONoGMeHd45ArdCkCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-27T02:18:00.713969Z"},"content_sha256":"fe4192142ff0c58e9a5e05096a2c6fd3d0df6c90f6cf5e2aa27f2ab79b14efb1","schema_version":"1.0","event_id":"sha256:fe4192142ff0c58e9a5e05096a2c6fd3d0df6c90f6cf5e2aa27f2ab79b14efb1"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/GKRSQV6IIGIS5VA2HXRRIT7SZG/bundle.json","state_url":"https://pith.science/pith/GKRSQV6IIGIS5VA2HXRRIT7SZG/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/GKRSQV6IIGIS5VA2HXRRIT7SZG/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-05-27T02:18:00Z","links":{"resolver":"https://pith.science/pith/GKRSQV6IIGIS5VA2HXRRIT7SZG","bundle":"https://pith.science/pith/GKRSQV6IIGIS5VA2HXRRIT7SZG/bundle.json","state":"https://pith.science/pith/GKRSQV6IIGIS5VA2HXRRIT7SZG/state.json","well_known_bundle":"https://pith.science/.well-known/pith/GKRSQV6IIGIS5VA2HXRRIT7SZG/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2015:GKRSQV6IIGIS5VA2HXRRIT7SZG","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":"7d30a1ea899784af7b57ecfda53026461696e572f072bfd2174caab5816527dc","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-08-20T18:51:41Z","title_canon_sha256":"85347d837e59e8dd57808bbce06f97a8b44e4208147d756ae8353d65af51d27a"},"schema_version":"1.0","source":{"id":"1508.05070","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1508.05070","created_at":"2026-05-18T01:32:59Z"},{"alias_kind":"arxiv_version","alias_value":"1508.05070v1","created_at":"2026-05-18T01:32:59Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1508.05070","created_at":"2026-05-18T01:32:59Z"},{"alias_kind":"pith_short_12","alias_value":"GKRSQV6IIGIS","created_at":"2026-05-18T12:29:22Z"},{"alias_kind":"pith_short_16","alias_value":"GKRSQV6IIGIS5VA2","created_at":"2026-05-18T12:29:22Z"},{"alias_kind":"pith_short_8","alias_value":"GKRSQV6I","created_at":"2026-05-18T12:29:22Z"}],"graph_snapshots":[{"event_id":"sha256:fe4192142ff0c58e9a5e05096a2c6fd3d0df6c90f6cf5e2aa27f2ab79b14efb1","target":"graph","created_at":"2026-05-18T01:32:59Z","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"},"paper":{"abstract_excerpt":"We have obtained Gemini/GMOS spectra of 28 regions located across the interacting group NGC 6845, spanning from the inner regions of the four major galaxies (NGC 6845A, B, C, D) to the tidal tails of NGC 6845A. All regions in the tails are star-forming objects with ages younger than 10 Myr. We derived the gas-phase metallicity gradients across NGC 6845A and its two tails and we find that these are shallower than those for isolated galaxies. NGC 6845A has a gas-phase oxygen central metallicity of \\mbox{12+log(O/H)$\\sim$8.5} and a flat gas-phase metallicity gradient ($\\beta$=0.002$\\pm$0.004 dex ","authors_text":"C. Mendes de Oliveira, D. F. de Mello, D. Olave-Rojas, E. R. Carrasco, S. Scarano Jr, S. Torres-Flores","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-08-20T18:51:41Z","title":"NGC 6845: metallicity gradients and star formation in a complex compact group"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1508.05070","kind":"arxiv","version":1},"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":"sha256:85b7decdfa5370ef4ae5e6197210ecb9c63afeaf352cd5256bac70ab6b4b18c8","target":"record","created_at":"2026-05-18T01:32:59Z","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":"7d30a1ea899784af7b57ecfda53026461696e572f072bfd2174caab5816527dc","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-08-20T18:51:41Z","title_canon_sha256":"85347d837e59e8dd57808bbce06f97a8b44e4208147d756ae8353d65af51d27a"},"schema_version":"1.0","source":{"id":"1508.05070","kind":"arxiv","version":1}},"canonical_sha256":"32a32857c841912ed41a3de3144ff2c9975bc29bf0b6a59d7d2afb080611ab08","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"32a32857c841912ed41a3de3144ff2c9975bc29bf0b6a59d7d2afb080611ab08","first_computed_at":"2026-05-18T01:32:59.141154Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:32:59.141154Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"ETxq3W6h+euVEFRgulXS8WxUvvXdfUppF0TmQLjmXDf1B2n46pVV6pYJRX1jelLH3lLRCpmCqi8KT6hjP2PdCg==","signature_status":"signed_v1","signed_at":"2026-05-18T01:32:59.141644Z","signed_message":"canonical_sha256_bytes"},"source_id":"1508.05070","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:85b7decdfa5370ef4ae5e6197210ecb9c63afeaf352cd5256bac70ab6b4b18c8","sha256:fe4192142ff0c58e9a5e05096a2c6fd3d0df6c90f6cf5e2aa27f2ab79b14efb1"],"state_sha256":"538aa43b096cc5d5b7d38bc24fb5b722ef60b37459859394b0ce43334dd76994"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"7Az6g9RFdJkPMwHU8K6v9eJjyXksYVM3phUaLU/8N92H4ZALP+9UqWmqL4zibKKbcExoixPvcuJIS9M/Wo4sDQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-27T02:18:00.717292Z","bundle_sha256":"911db665ec2a70e375e897ae9c53b7752e52855713ff3314adb8e73bbdb9bb82"}}