{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2015:IRJ3K2TWB7BTUJSWFG3SL6DDCL","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":"a43aef9bd3d72c9701bcd2d02a9ecf8be519fba8704a82070a03f62e2ea668cc","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2015-11-23T21:00:15Z","title_canon_sha256":"76d3a8c2101776c8c18604dbf64d43777925e0a12247e49565028ae2f09309ab"},"schema_version":"1.0","source":{"id":"1511.07448","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1511.07448","created_at":"2026-05-18T01:15:00Z"},{"alias_kind":"arxiv_version","alias_value":"1511.07448v2","created_at":"2026-05-18T01:15:00Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1511.07448","created_at":"2026-05-18T01:15:00Z"},{"alias_kind":"pith_short_12","alias_value":"IRJ3K2TWB7BT","created_at":"2026-05-18T12:29:25Z"},{"alias_kind":"pith_short_16","alias_value":"IRJ3K2TWB7BTUJSW","created_at":"2026-05-18T12:29:25Z"},{"alias_kind":"pith_short_8","alias_value":"IRJ3K2TW","created_at":"2026-05-18T12:29:25Z"}],"graph_snapshots":[{"event_id":"sha256:bb342db1ae572807eff80c191142550c8be0ce4b5080f83a7f58ef4427bc5c2e","target":"graph","created_at":"2026-05-18T01:15:00Z","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":"Currently several low-frequency experiments are being planned to study the nature of the first stars using the redshifted 21-cm signal from the cosmic dawn and epoch of reionization. Using a one-dimensional radiative transfer code, we model the 21-cm signal pattern around the early sources for different source models, i.e., the metal-free Population III (PopIII) stars, primordial galaxies consisting of Population II (PopII) stars, mini-QSOs and high-mass X-ray binaries (HMXBs). We investigate the detectability of these sources by comparing the 21-cm visibility signal with the system noise appr","authors_text":"India), Kanan K. Datta (Presidency University, Raghunath Ghara (NCRA-TIFR, T. Roy Choudhury (NCRA-TIFR","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2015-11-23T21:00:15Z","title":"21-cm signature of the first sources in the Universe: Prospects of detection with SKA"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1511.07448","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":"sha256:4d3141986154aba880c8b7663b213bc85f8a6741715bbfd62b4ec150f2753111","target":"record","created_at":"2026-05-18T01:15:00Z","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":"a43aef9bd3d72c9701bcd2d02a9ecf8be519fba8704a82070a03f62e2ea668cc","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2015-11-23T21:00:15Z","title_canon_sha256":"76d3a8c2101776c8c18604dbf64d43777925e0a12247e49565028ae2f09309ab"},"schema_version":"1.0","source":{"id":"1511.07448","kind":"arxiv","version":2}},"canonical_sha256":"4453b56a760fc33a265629b725f86312ff181648fa4117fa1f2343969d83af03","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"4453b56a760fc33a265629b725f86312ff181648fa4117fa1f2343969d83af03","first_computed_at":"2026-05-18T01:15:00.188089Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:15:00.188089Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"OYjzPnvPr9WavEOnhnlOQkWZadRfFm1iNMK2bBmM9D05MxCCer7a+H4sZi3oAfMUn8UAR9CkKMtqNe9GnuOOBg==","signature_status":"signed_v1","signed_at":"2026-05-18T01:15:00.188631Z","signed_message":"canonical_sha256_bytes"},"source_id":"1511.07448","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:4d3141986154aba880c8b7663b213bc85f8a6741715bbfd62b4ec150f2753111","sha256:bb342db1ae572807eff80c191142550c8be0ce4b5080f83a7f58ef4427bc5c2e"],"state_sha256":"1e4db3fe9c6467151bf57763d97a522dd20059003a0d9b65251df9b741936dcd"}