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arXiv · 2610.28182

Hidden engines in tidal disruption events: multimessenger signatures in a lepto-hadronic framework

D. Kantzas·D. A. Langis·I. Liodakis·A. Paggi
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Abstract

Tidal disruption events (TDEs) provide a unique laboratory for studying transient accretion, outflows, particle acceleration, and the possible connection between stellar disruptions and high-energy neutrinos. Motivated by recent candidate TDE-neutrino associations and by the forthcoming sensitivity of multimessenger facilities, we investigate under which physical conditions TDEs can be detected in MeV, GeV, and TeV gamma rays, and in high-energy neutrinos. We develop a lepto-hadronic emission framework and apply it to three representative sources: AT2019dsg, AT2019ehz, and ASASSN-14li. For each source we explore a set of physically motivated models that vary the proton and electron spectral indices, the minimum Lorentz factor of non-thermal protons, the particle energy partition, the acceleration efficiency, the magnetic compactness, and the presence of a compact corona. We compute the broadband spectral energy distributions, the associated muon-neutrino spectra, and compare them with reference sensitivities for COSI, Fermi/LAT, CTAO, and KM3NeT/ARCA. We find that hard proton spectra and/or large minimum proton Lorentz factors are the most favourable conditions for TeV gamma-ray and neutrino detectability, while GeV-bright models can be predominantly leptonic and neutrino quiet. AT2019dsg and AT2019ehz can reach the CTAO and KM3NeT benchmarks in hadronically favourable configurations, whereas ASASSN-14li is more naturally bright in the MeV-GeV band and constrained by its radio synchrotron emission. Our results highlight the importance of combining MeV, GeV, TeV, radio, and neutrino observations to distinguish between transparent, hidden, and lepton-dominated TDE emission regimes.

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D. Kantzas, D. A. Langis, I. Liodakis, A. Paggi. 2026-10-20. Hidden engines in tidal disruption events: multimessenger signatures in a lepto-hadronic framework. https://arxiv.org/abs/2610.28182

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