{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2019:6CIUNHTW2YNRLSD4JIAGKDFNUT","short_pith_number":"pith:6CIUNHTW","schema_version":"1.0","canonical_sha256":"f091469e76d61b15c87c4a00650cada4fe52d7bfff45b979612071ddf7b623fa","source":{"kind":"arxiv","id":"1909.00967","version":1},"attestation_state":"computed","paper":{"title":"Quasars Have Fewer Close Companions than Normal Galaxies","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Ian D. McGreer, Jan-Torge Schindler, Minghao Yue, Xiaohui Fan, Yun-Hsin Huang","submitted_at":"2019-09-03T06:16:08Z","abstract_excerpt":"We investigate the distribution of companion galaxies around quasars using {\\em Hubble Space Telescope} ({\\em HST}) Advanced Camera for Surveys Wide Field Camera (ACS/WFC) archival images. Our master sample contains 532 quasars which have been observed by {\\em HST} ACS/WFC, spanning a wide range of luminosity $(-31<M_i(z=2)<-23)$ and redshift ($0.3<z<3$). We search for companions around the quasars with projected distance of $10\\text{ kpc}<d<100\\text{ kpc}$. PSF subtraction is performed to enhance the completeness for close companions. The completeness is estimated to be high $(>90\\%)$ even fo"},"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":"1909.00967","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-09-03T06:16:08Z","cross_cats_sorted":[],"title_canon_sha256":"51ac1fb6e08c1949f1dcb98f011e01a43d2b96ae2e225682e257c7200776aa04","abstract_canon_sha256":"bcf3a20700d0ecb16cba323faadd745a479c551581805d5164a64d4279834a15"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T00:10:43.069949Z","signature_b64":"FP9qwj1R5lON951/gwsULRO4/GcHxaLePkrymN+DhUlTp0msR8cic3WrZYBKPUQjo6uw2dABilw4A6PWAJvQAQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"f091469e76d61b15c87c4a00650cada4fe52d7bfff45b979612071ddf7b623fa","last_reissued_at":"2026-07-05T00:10:43.069553Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T00:10:43.069553Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Quasars Have Fewer Close Companions than Normal Galaxies","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Ian D. McGreer, Jan-Torge Schindler, Minghao Yue, Xiaohui Fan, Yun-Hsin Huang","submitted_at":"2019-09-03T06:16:08Z","abstract_excerpt":"We investigate the distribution of companion galaxies around quasars using {\\em Hubble Space Telescope} ({\\em HST}) Advanced Camera for Surveys Wide Field Camera (ACS/WFC) archival images. Our master sample contains 532 quasars which have been observed by {\\em HST} ACS/WFC, spanning a wide range of luminosity $(-31<M_i(z=2)<-23)$ and redshift ($0.3<z<3$). We search for companions around the quasars with projected distance of $10\\text{ kpc}<d<100\\text{ kpc}$. PSF subtraction is performed to enhance the completeness for close companions. The completeness is estimated to be high $(>90\\%)$ even fo"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1909.00967","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/1909.00967/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"1909.00967","created_at":"2026-07-05T00:10:43.069609+00:00"},{"alias_kind":"arxiv_version","alias_value":"1909.00967v1","created_at":"2026-07-05T00:10:43.069609+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1909.00967","created_at":"2026-07-05T00:10:43.069609+00:00"},{"alias_kind":"pith_short_12","alias_value":"6CIUNHTW2YNR","created_at":"2026-07-05T00:10:43.069609+00:00"},{"alias_kind":"pith_short_16","alias_value":"6CIUNHTW2YNRLSD4","created_at":"2026-07-05T00:10:43.069609+00:00"},{"alias_kind":"pith_short_8","alias_value":"6CIUNHTW","created_at":"2026-07-05T00:10:43.069609+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/6CIUNHTW2YNRLSD4JIAGKDFNUT","json":"https://pith.science/pith/6CIUNHTW2YNRLSD4JIAGKDFNUT.json","graph_json":"https://pith.science/api/pith-number/6CIUNHTW2YNRLSD4JIAGKDFNUT/graph.json","events_json":"https://pith.science/api/pith-number/6CIUNHTW2YNRLSD4JIAGKDFNUT/events.json","paper":"https://pith.science/paper/6CIUNHTW"},"agent_actions":{"view_html":"https://pith.science/pith/6CIUNHTW2YNRLSD4JIAGKDFNUT","download_json":"https://pith.science/pith/6CIUNHTW2YNRLSD4JIAGKDFNUT.json","view_paper":"https://pith.science/paper/6CIUNHTW","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1909.00967&json=true","fetch_graph":"https://pith.science/api/pith-number/6CIUNHTW2YNRLSD4JIAGKDFNUT/graph.json","fetch_events":"https://pith.science/api/pith-number/6CIUNHTW2YNRLSD4JIAGKDFNUT/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/6CIUNHTW2YNRLSD4JIAGKDFNUT/action/timestamp_anchor","attest_storage":"https://pith.science/pith/6CIUNHTW2YNRLSD4JIAGKDFNUT/action/storage_attestation","attest_author":"https://pith.science/pith/6CIUNHTW2YNRLSD4JIAGKDFNUT/action/author_attestation","sign_citation":"https://pith.science/pith/6CIUNHTW2YNRLSD4JIAGKDFNUT/action/citation_signature","submit_replication":"https://pith.science/pith/6CIUNHTW2YNRLSD4JIAGKDFNUT/action/replication_record"}},"created_at":"2026-07-05T00:10:43.069609+00:00","updated_at":"2026-07-05T00:10:43.069609+00:00"}