{"paper":{"title":"High-Frequency Gravitational Waves from the Galactic Pulsar Population","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Galactic pulsars generate an astrophysical foreground of high-frequency gravitational waves in the MHz band that can overlap with and partially obscure the thermal signal from early-Universe plasma.","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"Anne S. Freise, Jamie I. McDonald, Kirill Riabtsev, Samuel J. Witte","submitted_at":"2026-04-17T15:59:51Z","abstract_excerpt":"The high-frequency gravitational-wave band is often discussed primarily in the context of new physics, but realistic Standard-Model foregrounds remain incompletely characterized. We investigate pulsar polar caps as a physically motivated astrophysical source of high-frequency gravitational waves, generated by repeated discharge cycles in compact near-surface plasma gaps. Our baseline result is population-level: we construct the signal from the Galactic normal-pulsar population rather than from a single especially favorable object. To do so, we calibrate the source dynamics with particle-in-cel"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"Integrating this description over a normal-pulsar population, we find an astrophysical foreground in the MHz-scale high-frequency band that can overlap with and partially obscure the thermal gravitational-wave signal sourced by the plasma of the early Universe.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The normalization remains sensitive to the modeled assumptions about discharge cycles, particle-in-cell calibration, and the lifting of longitudinal discharge to cap-scale emission.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"The Galactic normal-pulsar population produces a high-frequency gravitational-wave foreground in the MHz range from polar-cap discharges that can partially obscure primordial thermal signals.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Galactic pulsars generate an astrophysical foreground of high-frequency gravitational waves in the MHz band that can overlap with and partially obscure the thermal signal from early-Universe plasma.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"62cfcf8d5d4c91328a5cd0663b69467696cd460806c0fb6e15db45c2f7e2f7d3"},"source":{"id":"2604.16191","kind":"arxiv","version":2},"verdict":{"id":"de9b347a-835c-41d3-b41e-631429dfe307","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-10T07:22:38.607278Z","strongest_claim":"Integrating this description over a normal-pulsar population, we find an astrophysical foreground in the MHz-scale high-frequency band that can overlap with and partially obscure the thermal gravitational-wave signal sourced by the plasma of the early Universe.","one_line_summary":"The Galactic normal-pulsar population produces a high-frequency gravitational-wave foreground in the MHz range from polar-cap discharges that can partially obscure primordial thermal signals.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The normalization remains sensitive to the modeled assumptions about discharge cycles, particle-in-cell calibration, and the lifting of longitudinal discharge to cap-scale emission.","pith_extraction_headline":"Galactic pulsars generate an astrophysical foreground of high-frequency gravitational waves in the MHz band that can overlap with and partially obscure the thermal signal from early-Universe plasma."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.16191/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"}