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arXiv · 2607.27827

Tidal Disruption Events with the SKA

Abstract

Tidal disruption events (TDEs) and related nuclear transients probe jet launching, disk formation and circularization, particle acceleration, and the circumnuclear medium (CNM). However, the small fraction of events launching relativistic jets, the weak or delayed radio emission of many thermal TDEs, and the black-hole demographics of galactic nuclei remain poorly understood. SKA, with microJy sensitivity, wide bandwidth, long baselines, rapid response, and commensal surveys across 50-350 MHz (SKA-Low) and 0.35-15.4 GHz (SKA-Mid), will transform this field. Its sensitivity, frequency coverage, and very long baseline interferometry (VLBI) capability will extend radio calorimetry from a few well-studied nearby events to volume-limited samples of non-relativistic outflows. The SKA will bring off-axis and mildly relativistic jets into routine reach, trace CNM density profiles through the evolution of the low-frequency synchrotron turnover, and localize faint off-nuclear transients with sub-arcsecond precision. These data will constrain jet incidence, energetics, geometry, and magnetization, map the CNM through shock interactions, test links to changing-look active galactic nuclei (AGN) and high-energy neutrinos, and identify off-nuclear events associated with recoiling supermassive or intermediate-mass black holes. We discuss the benefits of commensal surveys, rapid triggering, and SKA-VLBI, and provide predictions based on the projected performance of AA* and AA4. SKA will shift TDE radio studies from detailed case-by-case studies to population-scale inference, advancing studies of jet physics and black-hole demographics.

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T. An, A. J. Goodwin, J. C. A. Miller-Jones, M. Pérez-Torres, L. Rhodes, X. Shu. 2026-07-30. Tidal Disruption Events with the SKA. https://arxiv.org/abs/2607.27827

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