{"paper":{"title":"Radial evolution of Alfv\\'en wave Parametric Decay Instability in the near-Sun solar wind: Effects of Temperature Anisotropy","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Temperature anisotropy raises the maximum growth rate of Alfvén wave parametric decay by a factor of 1.5 in the near-Sun solar wind.","cross_cats":["physics.space-ph"],"primary_cat":"astro-ph.SR","authors_text":"Hayato Saguchi, Munehito Shoda, Yohei Kawazura, Yuto Katoh","submitted_at":"2026-04-24T12:18:40Z","abstract_excerpt":"Parametric decay instability (PDI) of Alfv\\'en wave is thought to play an important role in the dissipation of the large-amplitude Alfv\\'en waves and in the heating of magnetized plasmas. Temperature anisotropy is frequently observed by spacecraft, including Parker Solar Probe (PSP), in the near-Sun solar wind, yet its impact on PDI in the near-Sun solar wind has been understudied. We calculate the maximum growth rates of PDI, $\\gamma_{\\max}/\\omega_{0}$, where $\\omega_0$ is the frequency of the parent wave, by solving the linear dispersion relation of Chew-Goldberger-Low (CGL) equations under "},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"temperature anisotropy with T⊥0 > T∥0 increases γmax/ω0 by factors of ∼1.5 over R≃1--10 R0, whereas temperature anisotropy with T∥0 > T⊥0 decreases γmax/ω0 at larger R.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The three chosen background expansion models (spherically symmetric adiabatic, multi-source constrained, and PSP-constrained with Parker spiral) accurately capture the radial evolution of beta and temperature anisotropy in the real near-Sun solar wind.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Temperature anisotropy raises the maximum growth rate of Alfvén wave parametric decay instability by factors of about 1.5 in the near-Sun solar wind for parallel beta below 0.1 when perpendicular temperature exceeds parallel temperature.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Temperature anisotropy raises the maximum growth rate of Alfvén wave parametric decay by a factor of 1.5 in the near-Sun solar wind.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"1de6974df5d4436f82a6a8af1d243bb6d689cdd67869d1014d1ab0604ef35026"},"source":{"id":"2604.22489","kind":"arxiv","version":3},"verdict":{"id":"577b2ea5-e024-41f2-969c-33deb6bf74f3","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-08T09:47:48.608147Z","strongest_claim":"temperature anisotropy with T⊥0 > T∥0 increases γmax/ω0 by factors of ∼1.5 over R≃1--10 R0, whereas temperature anisotropy with T∥0 > T⊥0 decreases γmax/ω0 at larger R.","one_line_summary":"Temperature anisotropy raises the maximum growth rate of Alfvén wave parametric decay instability by factors of about 1.5 in the near-Sun solar wind for parallel beta below 0.1 when perpendicular temperature exceeds parallel temperature.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The three chosen background expansion models (spherically symmetric adiabatic, multi-source constrained, and PSP-constrained with Parker spiral) accurately capture the radial evolution of beta and temperature anisotropy in the real near-Sun solar wind.","pith_extraction_headline":"Temperature anisotropy raises the maximum growth rate of Alfvén wave parametric decay by a factor of 1.5 in the near-Sun solar wind."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.22489/integrity.json","findings":[],"available":true,"detectors_run":[{"name":"ai_meta_artifact","ran_at":"2026-05-21T10:39:13.336033Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"doi_compliance","ran_at":"2026-05-19T23:56:31.937305Z","status":"completed","version":"1.0.0","findings_count":0}],"snapshot_sha256":"0f96bf817f53177202be370cb7bb491a65d74eec015d5a051dbea2b5afbbd967"},"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"}