{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:WZK3L6GRFWHYJIWMPCD2MF4BIM","short_pith_number":"pith:WZK3L6GR","canonical_record":{"source":{"id":"1901.07586","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-01-22T19:11:16Z","cross_cats_sorted":[],"title_canon_sha256":"c3a2b3f2f6945f91b0b598015b4bfee5e21eac2c096a3dcc090a2a512ee4c11d","abstract_canon_sha256":"c7272b855a6b695a72793d1ef9b8642242d543cc3ee51d3438f1260ce8b6d789"},"schema_version":"1.0"},"canonical_sha256":"b655b5f8d12d8f84a2cc7887a61781432364c10408a637dbf3eb40809a5c6182","source":{"kind":"arxiv","id":"1901.07586","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1901.07586","created_at":"2026-05-17T23:45:30Z"},{"alias_kind":"arxiv_version","alias_value":"1901.07586v1","created_at":"2026-05-17T23:45:30Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.07586","created_at":"2026-05-17T23:45:30Z"},{"alias_kind":"pith_short_12","alias_value":"WZK3L6GRFWHY","created_at":"2026-05-18T12:33:33Z"},{"alias_kind":"pith_short_16","alias_value":"WZK3L6GRFWHYJIWM","created_at":"2026-05-18T12:33:33Z"},{"alias_kind":"pith_short_8","alias_value":"WZK3L6GR","created_at":"2026-05-18T12:33:33Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:WZK3L6GRFWHYJIWMPCD2MF4BIM","target":"record","payload":{"canonical_record":{"source":{"id":"1901.07586","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-01-22T19:11:16Z","cross_cats_sorted":[],"title_canon_sha256":"c3a2b3f2f6945f91b0b598015b4bfee5e21eac2c096a3dcc090a2a512ee4c11d","abstract_canon_sha256":"c7272b855a6b695a72793d1ef9b8642242d543cc3ee51d3438f1260ce8b6d789"},"schema_version":"1.0"},"canonical_sha256":"b655b5f8d12d8f84a2cc7887a61781432364c10408a637dbf3eb40809a5c6182","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:45:30.726411Z","signature_b64":"oC8Pk73gG6MDw98js/YNGoRVzmnlAb+0D/fDKPyP1Qqt6Y6HNyGF3tAxbSjLs89N04kuANrS3ftrqfIu5fcZDg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"b655b5f8d12d8f84a2cc7887a61781432364c10408a637dbf3eb40809a5c6182","last_reissued_at":"2026-05-17T23:45:30.725727Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:45:30.725727Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1901.07586","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":"2026-05-17T23:45:30Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ZFFI4I9elRyh7DJS1WVHRVo6ryGTg0fjdTpI+r+o5uShKlerb6IlMBBFtfS5A/JNlSK4/SF5kxT7jSQi6BD0CQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-30T23:51:33.262951Z"},"content_sha256":"2d22770de1641498688f8f2cb53ef6610db3f5510c2bbe2a652e94a07f6098ed","schema_version":"1.0","event_id":"sha256:2d22770de1641498688f8f2cb53ef6610db3f5510c2bbe2a652e94a07f6098ed"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:WZK3L6GRFWHYJIWMPCD2MF4BIM","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Constraints on the HI Mass of NGC 1052-DF2","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Amy Sardone, D.J. Pisano, Joshua L. Mascoop, Nihan Pol, Sarah Burke-Spolaor","submitted_at":"2019-01-22T19:11:16Z","abstract_excerpt":"We report deep, single-dish 21 cm observations of NGC 1052-DF2, taken with the Green Bank Telescope. NGC 1052-DF2, proposed to be lacking in dark matter, is currently classified as an ultra-diffuse galaxy in the NGC 1052 group. We do not detect the galaxy, and derive an upper limit on the HI, mass. The galaxy is extremely gas-poor, and we find that a $3\\sigma \\, M_{HI}$ detection at a distance of 19 Mpc and using a line width of 3.2 km $\\rm s^{-1}$ would have an upper limit of $M_{HI,lim} < 5.5 \\times 10^5$ M$_{\\odot}$. At this mass limit, the gas fraction of neutral gas mass to stellar mass i"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.07586","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":"2026-05-17T23:45:30Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"pqTCN739aciCAUAi3SJMoOhBAMvCTmvF0ttzzHnjdMoAAeFHljntlT4H2sdp69nFMKDv6IMyWfCYYTFZWWWQAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-30T23:51:33.263550Z"},"content_sha256":"a720a537311b5509f299054157ac66eb656615ee31ccfe99e99f013da9da39ce","schema_version":"1.0","event_id":"sha256:a720a537311b5509f299054157ac66eb656615ee31ccfe99e99f013da9da39ce"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/WZK3L6GRFWHYJIWMPCD2MF4BIM/bundle.json","state_url":"https://pith.science/pith/WZK3L6GRFWHYJIWMPCD2MF4BIM/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/WZK3L6GRFWHYJIWMPCD2MF4BIM/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":"2026-05-30T23:51:33Z","links":{"resolver":"https://pith.science/pith/WZK3L6GRFWHYJIWMPCD2MF4BIM","bundle":"https://pith.science/pith/WZK3L6GRFWHYJIWMPCD2MF4BIM/bundle.json","state":"https://pith.science/pith/WZK3L6GRFWHYJIWMPCD2MF4BIM/state.json","well_known_bundle":"https://pith.science/.well-known/pith/WZK3L6GRFWHYJIWMPCD2MF4BIM/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:WZK3L6GRFWHYJIWMPCD2MF4BIM","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":"c7272b855a6b695a72793d1ef9b8642242d543cc3ee51d3438f1260ce8b6d789","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-01-22T19:11:16Z","title_canon_sha256":"c3a2b3f2f6945f91b0b598015b4bfee5e21eac2c096a3dcc090a2a512ee4c11d"},"schema_version":"1.0","source":{"id":"1901.07586","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1901.07586","created_at":"2026-05-17T23:45:30Z"},{"alias_kind":"arxiv_version","alias_value":"1901.07586v1","created_at":"2026-05-17T23:45:30Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.07586","created_at":"2026-05-17T23:45:30Z"},{"alias_kind":"pith_short_12","alias_value":"WZK3L6GRFWHY","created_at":"2026-05-18T12:33:33Z"},{"alias_kind":"pith_short_16","alias_value":"WZK3L6GRFWHYJIWM","created_at":"2026-05-18T12:33:33Z"},{"alias_kind":"pith_short_8","alias_value":"WZK3L6GR","created_at":"2026-05-18T12:33:33Z"}],"graph_snapshots":[{"event_id":"sha256:a720a537311b5509f299054157ac66eb656615ee31ccfe99e99f013da9da39ce","target":"graph","created_at":"2026-05-17T23:45:30Z","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 report deep, single-dish 21 cm observations of NGC 1052-DF2, taken with the Green Bank Telescope. NGC 1052-DF2, proposed to be lacking in dark matter, is currently classified as an ultra-diffuse galaxy in the NGC 1052 group. We do not detect the galaxy, and derive an upper limit on the HI, mass. The galaxy is extremely gas-poor, and we find that a $3\\sigma \\, M_{HI}$ detection at a distance of 19 Mpc and using a line width of 3.2 km $\\rm s^{-1}$ would have an upper limit of $M_{HI,lim} < 5.5 \\times 10^5$ M$_{\\odot}$. At this mass limit, the gas fraction of neutral gas mass to stellar mass i","authors_text":"Amy Sardone, D.J. Pisano, Joshua L. Mascoop, Nihan Pol, Sarah Burke-Spolaor","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-01-22T19:11:16Z","title":"Constraints on the HI Mass of NGC 1052-DF2"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.07586","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":"sha256:2d22770de1641498688f8f2cb53ef6610db3f5510c2bbe2a652e94a07f6098ed","target":"record","created_at":"2026-05-17T23:45:30Z","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":"c7272b855a6b695a72793d1ef9b8642242d543cc3ee51d3438f1260ce8b6d789","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-01-22T19:11:16Z","title_canon_sha256":"c3a2b3f2f6945f91b0b598015b4bfee5e21eac2c096a3dcc090a2a512ee4c11d"},"schema_version":"1.0","source":{"id":"1901.07586","kind":"arxiv","version":1}},"canonical_sha256":"b655b5f8d12d8f84a2cc7887a61781432364c10408a637dbf3eb40809a5c6182","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"b655b5f8d12d8f84a2cc7887a61781432364c10408a637dbf3eb40809a5c6182","first_computed_at":"2026-05-17T23:45:30.725727Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:45:30.725727Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"oC8Pk73gG6MDw98js/YNGoRVzmnlAb+0D/fDKPyP1Qqt6Y6HNyGF3tAxbSjLs89N04kuANrS3ftrqfIu5fcZDg==","signature_status":"signed_v1","signed_at":"2026-05-17T23:45:30.726411Z","signed_message":"canonical_sha256_bytes"},"source_id":"1901.07586","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:2d22770de1641498688f8f2cb53ef6610db3f5510c2bbe2a652e94a07f6098ed","sha256:a720a537311b5509f299054157ac66eb656615ee31ccfe99e99f013da9da39ce"],"state_sha256":"083f822aec79699f844d5d93d10d7e7ef7561f3c2919f4fa9e92d5ef6e208b6e"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"E+VflpU9Fqgwif18WbaWlP9FgnpEgq7z7PPbB5QD45eC6qHbDSHuPM2qxEgw6U+ukaPet+3UM6936lVsMCcuAQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-30T23:51:33.266976Z","bundle_sha256":"1a8b69209524e9484b63b92d2b0b1ab4eceb892427f5563dcb11ada4d6fcd722"}}