{"paper":{"title":"Studying dark gaps in Ly-$\\alpha$ forest transmission with large reionization simulations","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Simulations show that reionization ending near redshift 5.4 best matches the observed distribution of long dark gaps in the Ly-alpha forest.","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"Barun Maity, Benedetta Spina, Frederick B. Davies, Sarah E. I. Bosman","submitted_at":"2026-01-30T20:51:04Z","abstract_excerpt":"The physical conditions of the intergalactic medium (IGM) during the final stages of cosmic reionization ($z\\sim5.0-6.0$) are not yet fully understood. Recent reports of unexpectedly large-scale ($\\ge 150 h^{-1}\\mathrm{cMpc}$) correlation in Ly-$\\alpha$ transmission flux using extended XQR-30 quasar spectra pose interesting challenges on the reionization end stages. In this work, we investigate the Ly-$\\alpha$ forest dark-gap distribution (defined as regions with transmitted flux below 0.05) as another sensitive tracer of the IGM, using an efficient, large-volume ($\\sim 1 ~\\mathrm{Gpc}$) simul"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"The scenario involving a slightly later reionization completion (z∼5.4) provides the closest match, while a short constant mean free path model is disfavored by the data at lower redshifts. These findings give qualitative support for the emerging scenario of reionization end extending to z≤5.7, although they can not rule out a slightly early reionization with enhanced post-ionization ultraviolet background fluctuations.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"That varying only reionization redshift, IGM temperature, and ionizing-photon mean free path in the simulation suite captures the dominant physical drivers of dark-gap statistics without missing important effects such as inhomogeneous reionization or additional sources of UV fluctuations.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Large reionization simulations show that the distribution of dark gaps in the Ly-α forest favors models with reionization completing at z≈5.4 over earlier or constant short mean-free-path scenarios.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Simulations show that reionization ending near redshift 5.4 best matches the observed distribution of long dark gaps in the Ly-alpha forest.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"6dbacbe145209964060a01549f9e3d30eae74aac38c07955fee7ae8dcf1d2731"},"source":{"id":"2602.00301","kind":"arxiv","version":2},"verdict":{"id":"260744a5-f5b0-452b-9899-ee5ae9cddfd4","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-16T08:52:01.182177Z","strongest_claim":"The scenario involving a slightly later reionization completion (z∼5.4) provides the closest match, while a short constant mean free path model is disfavored by the data at lower redshifts. These findings give qualitative support for the emerging scenario of reionization end extending to z≤5.7, although they can not rule out a slightly early reionization with enhanced post-ionization ultraviolet background fluctuations.","one_line_summary":"Large reionization simulations show that the distribution of dark gaps in the Ly-α forest favors models with reionization completing at z≈5.4 over earlier or constant short mean-free-path scenarios.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"That varying only reionization redshift, IGM temperature, and ionizing-photon mean free path in the simulation suite captures the dominant physical drivers of dark-gap statistics without missing important effects such as inhomogeneous reionization or additional sources of UV fluctuations.","pith_extraction_headline":"Simulations show that reionization ending near redshift 5.4 best matches the observed distribution of long dark gaps in the Ly-alpha forest."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2602.00301/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":49,"sample":[{"doi":"","year":2013,"title":"Almgren, A. S., Bell, J. B., Lijewski, M. J., Luki ´c, Z., & Van Andel, E. 2013, ApJ, 765, 39 Bañados, E., Venemans, B. P., Mazzucchelli, C., et al. 2018, Nature, 553, 473","work_id":"885abc7b-6cb8-4356-af5b-a9a3a9c095a1","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2001,"title":"Barkana, R. & Loeb, A. 2001, Phys. Rep., 349, 125","work_id":"a02f9258-33e9-46f5-a9db-5a5d6832627e","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2015,"title":"Becker, G. D., Bolton, J. S., Madau, P., et al. 2015, MNRAS, 447, 3402","work_id":"3eadd0d2-a951-422a-bbde-a5aef9a76952","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2021,"title":"D., D’Aloisio, A., Christenson, H","work_id":"9b432309-7b24-4863-967e-c5e3f2ad4bc2","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2022,"title":"Bosman, S. E. I., Davies, F. B., Becker, G. D., et al. 2022, MNRAS, 514, 55","work_id":"0f78b0a4-91b4-4e57-be04-29a1be852451","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":49,"snapshot_sha256":"27f36e67f1ac9b99dd01d4daa2f12a65dbf88c0cff110ad2e2a296dd37ba2be8","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"}