{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:XON7EA276SQDP4FWOSXIFAHWVL","short_pith_number":"pith:XON7EA27","canonical_record":{"source":{"id":"1902.05073","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2019-02-13T19:00:00Z","cross_cats_sorted":[],"title_canon_sha256":"9afcfe851b98534229d323c97de1d962bbdd36783fbddae81b8aa958b353babb","abstract_canon_sha256":"e06e215e95203713e4d4b9ba6264e1503f12beb59b0028116c2afcc2b355fddd"},"schema_version":"1.0"},"canonical_sha256":"bb9bf2035ff4a037f0b674ae8280f6aae85adcc1f18a805b4e5ae03a1cec6efa","source":{"kind":"arxiv","id":"1902.05073","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1902.05073","created_at":"2026-05-17T23:52:35Z"},{"alias_kind":"arxiv_version","alias_value":"1902.05073v2","created_at":"2026-05-17T23:52:35Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1902.05073","created_at":"2026-05-17T23:52:35Z"},{"alias_kind":"pith_short_12","alias_value":"XON7EA276SQD","created_at":"2026-05-18T12:33:33Z"},{"alias_kind":"pith_short_16","alias_value":"XON7EA276SQDP4FW","created_at":"2026-05-18T12:33:33Z"},{"alias_kind":"pith_short_8","alias_value":"XON7EA27","created_at":"2026-05-18T12:33:33Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:XON7EA276SQDP4FWOSXIFAHWVL","target":"record","payload":{"canonical_record":{"source":{"id":"1902.05073","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2019-02-13T19:00:00Z","cross_cats_sorted":[],"title_canon_sha256":"9afcfe851b98534229d323c97de1d962bbdd36783fbddae81b8aa958b353babb","abstract_canon_sha256":"e06e215e95203713e4d4b9ba6264e1503f12beb59b0028116c2afcc2b355fddd"},"schema_version":"1.0"},"canonical_sha256":"bb9bf2035ff4a037f0b674ae8280f6aae85adcc1f18a805b4e5ae03a1cec6efa","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:52:35.949046Z","signature_b64":"hA7msWsTWNU+4Qy95yl4dZb3P6IFdqz89VxYmR9+P+mYkp3efRIAhOzOz1kU8B0pxk6FXThamZ7D+X0akQGiAQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"bb9bf2035ff4a037f0b674ae8280f6aae85adcc1f18a805b4e5ae03a1cec6efa","last_reissued_at":"2026-05-17T23:52:35.948564Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:52:35.948564Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1902.05073","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-17T23:52:35Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"1bs3njfeyr6MfHE1Z9+3nKteUZmh5ztUvaTFKFcJ/CAa0TUFFXRu9hIFl9vcRZPwa045n1bLWlam37pY3sJeAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-29T22:29:40.946525Z"},"content_sha256":"c27f5d490175883a272a347bef52d7822ffe899f9bfd399c30add5b0e36c3004","schema_version":"1.0","event_id":"sha256:c27f5d490175883a272a347bef52d7822ffe899f9bfd399c30add5b0e36c3004"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:XON7EA276SQDP4FWOSXIFAHWVL","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"X-Ray Spectral Variability of Ultraluminous X-Ray Sources in Extragalactic Globular Clusters","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"Arash Bahramian, Arunav Kundu, Kristen C. Dage, Mark B. Peacock, Omid Noroozi, Stephen E. Zepf, Thomas J. Maccarone","submitted_at":"2019-02-13T19:00:00Z","abstract_excerpt":"A number of ultraluminous X-ray sources (ULXs) are physically associated with extragalactic globular clusters (GCs). We undertake a systematic X-ray analysis of eight of the brightest of these sources. We fit the spectra of the GC ULXs to single power law and single disk models. We find that the data never require that any of the sources change between a disk and a power law across successive observations. The GC ULXs best fit by a single disk show a bimodal distribution: they either have temperatures well below 0.5 keV, or variable temperatures ranging above 0.5 keV up to 2~keV. The GC ULXs w"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1902.05073","kind":"arxiv","version":2},"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":"2026-05-17T23:52:35Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"h8H7DNHBrgbSLda/Ht/HREVG6yQrD1rSbUgIwsAiwJVxomD0+jDkUcSyXf8JN8DbETOGE87d6rHt/YrXIFzbAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-29T22:29:40.947189Z"},"content_sha256":"276c603c3c43f4c1b3ec0ceb708b89c35fba590cf2a753987ddd8b8304bb01d0","schema_version":"1.0","event_id":"sha256:276c603c3c43f4c1b3ec0ceb708b89c35fba590cf2a753987ddd8b8304bb01d0"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/XON7EA276SQDP4FWOSXIFAHWVL/bundle.json","state_url":"https://pith.science/pith/XON7EA276SQDP4FWOSXIFAHWVL/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/XON7EA276SQDP4FWOSXIFAHWVL/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":"2026-05-29T22:29:40Z","links":{"resolver":"https://pith.science/pith/XON7EA276SQDP4FWOSXIFAHWVL","bundle":"https://pith.science/pith/XON7EA276SQDP4FWOSXIFAHWVL/bundle.json","state":"https://pith.science/pith/XON7EA276SQDP4FWOSXIFAHWVL/state.json","well_known_bundle":"https://pith.science/.well-known/pith/XON7EA276SQDP4FWOSXIFAHWVL/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:XON7EA276SQDP4FWOSXIFAHWVL","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":"e06e215e95203713e4d4b9ba6264e1503f12beb59b0028116c2afcc2b355fddd","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2019-02-13T19:00:00Z","title_canon_sha256":"9afcfe851b98534229d323c97de1d962bbdd36783fbddae81b8aa958b353babb"},"schema_version":"1.0","source":{"id":"1902.05073","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1902.05073","created_at":"2026-05-17T23:52:35Z"},{"alias_kind":"arxiv_version","alias_value":"1902.05073v2","created_at":"2026-05-17T23:52:35Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1902.05073","created_at":"2026-05-17T23:52:35Z"},{"alias_kind":"pith_short_12","alias_value":"XON7EA276SQD","created_at":"2026-05-18T12:33:33Z"},{"alias_kind":"pith_short_16","alias_value":"XON7EA276SQDP4FW","created_at":"2026-05-18T12:33:33Z"},{"alias_kind":"pith_short_8","alias_value":"XON7EA27","created_at":"2026-05-18T12:33:33Z"}],"graph_snapshots":[{"event_id":"sha256:276c603c3c43f4c1b3ec0ceb708b89c35fba590cf2a753987ddd8b8304bb01d0","target":"graph","created_at":"2026-05-17T23:52:35Z","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":"A number of ultraluminous X-ray sources (ULXs) are physically associated with extragalactic globular clusters (GCs). We undertake a systematic X-ray analysis of eight of the brightest of these sources. We fit the spectra of the GC ULXs to single power law and single disk models. We find that the data never require that any of the sources change between a disk and a power law across successive observations. The GC ULXs best fit by a single disk show a bimodal distribution: they either have temperatures well below 0.5 keV, or variable temperatures ranging above 0.5 keV up to 2~keV. The GC ULXs w","authors_text":"Arash Bahramian, Arunav Kundu, Kristen C. Dage, Mark B. Peacock, Omid Noroozi, Stephen E. Zepf, Thomas J. Maccarone","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2019-02-13T19:00:00Z","title":"X-Ray Spectral Variability of Ultraluminous X-Ray Sources in Extragalactic Globular Clusters"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1902.05073","kind":"arxiv","version":2},"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:c27f5d490175883a272a347bef52d7822ffe899f9bfd399c30add5b0e36c3004","target":"record","created_at":"2026-05-17T23:52:35Z","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":"e06e215e95203713e4d4b9ba6264e1503f12beb59b0028116c2afcc2b355fddd","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2019-02-13T19:00:00Z","title_canon_sha256":"9afcfe851b98534229d323c97de1d962bbdd36783fbddae81b8aa958b353babb"},"schema_version":"1.0","source":{"id":"1902.05073","kind":"arxiv","version":2}},"canonical_sha256":"bb9bf2035ff4a037f0b674ae8280f6aae85adcc1f18a805b4e5ae03a1cec6efa","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"bb9bf2035ff4a037f0b674ae8280f6aae85adcc1f18a805b4e5ae03a1cec6efa","first_computed_at":"2026-05-17T23:52:35.948564Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:52:35.948564Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"hA7msWsTWNU+4Qy95yl4dZb3P6IFdqz89VxYmR9+P+mYkp3efRIAhOzOz1kU8B0pxk6FXThamZ7D+X0akQGiAQ==","signature_status":"signed_v1","signed_at":"2026-05-17T23:52:35.949046Z","signed_message":"canonical_sha256_bytes"},"source_id":"1902.05073","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:c27f5d490175883a272a347bef52d7822ffe899f9bfd399c30add5b0e36c3004","sha256:276c603c3c43f4c1b3ec0ceb708b89c35fba590cf2a753987ddd8b8304bb01d0"],"state_sha256":"e060b97d8ca9df970743ae9e89086db0a154199802e074ce9126036a56baf5ae"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"zFfph+HDeI3UqjVk+eb2nmwitBKXMeDMWv1XbtYbM/u8+o45Jisy0zFb7IM69+qHupcO2NHOIyq8km1kadeQCQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-29T22:29:40.951117Z","bundle_sha256":"b318eb7d69ff2882a0f5d350392a68fe0698ee4397eb0641f6f7836370416d8d"}}