{"arxiv_id":"2611.05880","title":"The kinematic Kelvin-Helmholtz instability-driven dynamo: implications for merging compact objects","abstract":"Binary neutron star (BNS) mergers excite a Kelvin--Helmholtz instability (KHI) in the shear layer between them. It is parasitized upon by the magnetic field to form a powerful magnetic dynamo. Using a large ensemble of high-resolution visco-resistive KHI-driven dynamo simulations we construct analytical, asymptotic in Reynolds number ($\\rm{Re}$) models for the magnetic field growth rates and mean vertical field dynamo onset times. Our models suggest that in the $\\rm{Re} \\gg 1$ limit, the mean vertical field is seeded immediately, kinematic growth rates become asymptotic in $\\rm{Re}$, and the dynamo moves out of the kinematic stage on $\\mathcal{O}(0.1\\,\\rm{ms})$ timescales, readily attaining magnetar-strength fields during this transition. This suggests that most global BNS merger simulations are not time-resolving the correct KHI-driven dynamo regime.","primary_cat":"astro-ph.HE","cross_cats":["astro-ph.GA","astro-ph.SR","physics.flu-dyn"],"submitted_at":"2026-11-04T03:16:55+00:00","latest_version":1,"source":"arxiv","source_label":"arXiv","source_url":null,"has_pdf":true,"has_source":false,"verdict":"ACCEPT","confidence":"HIGH","one_line_summary":"Kelvin-Helmholtz instability-driven dynamos in neutron star mergers exhibit Reynolds-number-independent growth and produce magnetar-strength fields in under 0.5 ms, contradicting the standard turbulence dynamo picture.","novelty_score":7.0,"correctness_risk":"low","formal_verification":"none","upvotes":0,"downvotes":0,"pith_score":0,"inbound_count":0,"_links":{"html":"https://pith.science/paper/2611.05880","verdict":"/api/v1/verdicts/2611.05880"}}