{"paper":{"title":"Double Neutron Star Delay Times Across Cosmic Metallicities: The Role of Helium Star Progenitors","license":"http://creativecommons.org/licenses/by/4.0/","headline":"Helium main-sequence radii set a minimum orbital size that pushes most double neutron star mergers to occur 80-250 million years after star formation.","cross_cats":["astro-ph.GA","astro-ph.HE"],"primary_cat":"astro-ph.SR","authors_text":"Abhishek Chattaraj, Elizabeth Teng, Jeff J. Andrews, Max Briel, Philipp M. Srivastava, Seth Gossage, Tassos Fragos, Vicky Kalogera","submitted_at":"2026-05-04T20:10:59Z","abstract_excerpt":"Metallicity can play a significant role in massive binary evolution through its impact on the opacity within stellar interiors and wind-driven mass loss. In this work, we investigate how the double neutron star (DNS) delay time distribution (DTD) is shaped by the metallicity-dependent evolution of the helium star$-$NS progenitor system. Drawing from insights rooted in single and binary star physics, we argue that at a given metallicity, the stellar radius during the helium main-sequence sets a lower limit on the size of the DNS orbit at birth. We then perform population synthesis with the deta"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"Our results indicate that, independent of binary physics assumptions, the majority of DNS mergers across metallicities occur typically no earlier than ≃ 40 Myr after star formation and peaks strongly between 80-250 Myr. Roughly 15% of DNSs merge within 80 Myr... while ≳ 20% merge on delay times >1 Gyr.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"At a given metallicity, the stellar radius during the helium main-sequence sets a lower limit on the size of the DNS orbit at birth, drawn from insights rooted in single and binary star physics.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Simulations show double neutron star mergers peak 80-250 million years after star formation across metallicities, with 15% quick mergers and over 20% delayed over a billion years.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Helium main-sequence radii set a minimum orbital size that pushes most double neutron star mergers to occur 80-250 million years after star formation.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"be20d34c9eaf10ae62851975b3e04cb2b05f52a44ab1a29b976307a258c329e3"},"source":{"id":"2605.03128","kind":"arxiv","version":2},"verdict":{"id":"dcad245d-7e70-439b-adce-d8e1561be9a9","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-08T17:25:58.953919Z","strongest_claim":"Our results indicate that, independent of binary physics assumptions, the majority of DNS mergers across metallicities occur typically no earlier than ≃ 40 Myr after star formation and peaks strongly between 80-250 Myr. Roughly 15% of DNSs merge within 80 Myr... while ≳ 20% merge on delay times >1 Gyr.","one_line_summary":"Simulations show double neutron star mergers peak 80-250 million years after star formation across metallicities, with 15% quick mergers and over 20% delayed over a billion years.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"At a given metallicity, the stellar radius during the helium main-sequence sets a lower limit on the size of the DNS orbit at birth, drawn from insights rooted in single and binary star physics.","pith_extraction_headline":"Helium main-sequence radii set a minimum orbital size that pushes most double neutron star mergers to occur 80-250 million years after star formation."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2605.03128/integrity.json","findings":[],"available":true,"detectors_run":[{"name":"ai_meta_artifact","ran_at":"2026-05-20T14:36:32.128182Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"doi_title_agreement","ran_at":"2026-05-20T02:01:21.745874Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"doi_compliance","ran_at":"2026-05-19T15:41:40.122052Z","status":"completed","version":"1.0.0","findings_count":0}],"snapshot_sha256":"0533d59eeafd3ce603f94a471d1d07986ce92602f98061f7291f84eb55b05246"},"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"}