Exploring supernova neutrino mass ordering at DUNE via quantum entanglement

The Deep Underground Neutrino Experiment (DUNE) offers strong sensitivity to neutrinos from a Galactic core collapse supernova, providing a powerful probe of neutrino flavor conversion and the neutrino mass ordering. In this work, we study supernova neutrino oscillations at DUNE using quantum entanglement as an organizing framework. Treating the three flavor neutrino system as an effective multipartite quantum state, we quantify flavor correlations through the entanglement of formation, concurrence, and negativity, expressed directly in terms of flavor survival and transition probabilities. Benchmark scenarios defined by representative variations of the electron neutrino survival probability are constructed for each entanglement measure. Event rates and fluences are computed for a supernova at 10 kpc, and the mass ordering sensitivity is evaluated using detector-level simulations performed with the \texttt{SNOwGLoBES} framework, employing the Garching supernova flux model and including the dominant detection channels in liquid argon: $ν_e$ and $\barν_e$ charged-current interactions on argon and elastic scattering on electrons. We analyze both individual and combined detection channels and incorporate $5%$ normalization and energy calibration systematic uncertainties. Our results show that DUNE achieves a $5σ$ determination of the neutrino mass ordering for a supernova at distances of $\sim 20$~kpc for the $ν_e$ charged current channel and $\sim 2$~kpc for the $\barν_e$ channel, with the reach depending on the entanglement scenario considered. These results demonstrate that entanglement based observables provide a complementary and robust framework for probing supernova neutrino oscillations and the neutrino mass ordering.

💡 Research Summary

This paper investigates the capability of the Deep Underground Neutrino Experiment (DUNE) to determine the neutrino mass ordering (normal versus inverted hierarchy) from a Galactic core‑collapse supernova by exploiting quantum‑entanglement concepts. The authors treat the three‑flavor neutrino system as an effective three‑qubit state and express three widely used entanglement measures—entanglement of formation (EOF), concurrence (CON), and negativity (NEG)—directly in terms of the flavor survival and transition probabilities that govern supernova neutrino oscillations.

First, the theoretical framework is laid out. The flavor eigenstates (|\nu_\alpha\rangle) ((\alpha=e,\mu,\tau)) are related to the mass eigenstates via the PMNS matrix. By adopting an occupation‑number representation, each flavor mode is mapped onto a qubit (|100\rangle,|010\rangle,|001\rangle). The time‑evolved state (|\nu_\alpha(t)\rangle) becomes a superposition of these basis states with amplitudes (\bar U_{\alpha i}(t)). From the resulting density matrix (\rho_\alpha(t)) the authors derive explicit formulas for EOF (Eq. 13), CON (Eq. 15) and NEG (Eq. 17) that involve only the probabilities (P_{\alpha\beta}). Figure 1 illustrates how each entanglement measure varies with the electron‑neutrino survival probability (P_{ee}), showing a characteristic rise to a maximum around (P_{ee}\sim0.5) and a decline toward the extremes.

Next, the supernova neutrino flux is modeled using a pinched‑thermal spectrum (Eq. 18) with average energies and pinching parameters taken from the Garching simulation suite. The authors incorporate the Mikheyev‑Smirnov‑Wolfenstein (MSW) effect and introduce a “Δp” term that encodes the contribution of quantum correlations (i.e., the chosen entanglement benchmark) to the effective electron‑neutrino and antineutrino fluxes at Earth (Eq. 20). Distinct expressions are provided for normal hierarchy (NH) and inverted hierarchy (IH), highlighting how the weighting of the original (\nu_e) and non‑electron (\nu_x) components depends on both the mixing angles and the entanglement‑induced Δp.

The experimental side uses the SNOwGLoBES package to simulate DUNE’s response to a supernova at 10 kpc. Three detection channels dominate in liquid argon: (A) (\nu_e) charged‑current (CC) on ({}^{40})Ar, (B) (\bar\nu_e) CC on ({}^{40})Ar, and (C) elastic scattering on electrons. The authors include realistic cross‑sections, energy thresholds, detection efficiencies, and systematic uncertainties (5 % on overall normalization and energy calibration). Event spectra are generated for several benchmark Δp values that correspond to representative EOF, CON², and NEG ranges listed in Table I.

Statistical sensitivity is assessed via a χ² comparison between NH and IH hypotheses, with a 5σ discovery criterion. The results show a strong dependence on both the detection channel and the entanglement scenario. For the (\nu_e) CC channel, the most optimistic entanglement benchmark (EOF≈1.2) yields a 5σ mass‑ordering determination out to ∼20 kpc, essentially covering the entire Milky Way. The (\bar\nu_e) CC channel is less sensitive; even under favorable entanglement conditions it reaches 5σ only up to ∼2 kpc. Combining the two channels modestly improves the reach but does not surpass the (\nu_e) CC dominance.

The key insights are: (1) quantum‑entanglement measures introduce non‑linear modifications to the flavor probability landscape, providing an additional lever arm on the mass ordering beyond simple event‑rate or spectral shape analyses; (2) these entanglement‑based observables are largely independent of the dominant systematic uncertainties, offering a robust complementary probe; (3) DUNE’s exceptional (\nu_e) CC sensitivity to the early neutronization burst makes it the optimal venue for exploiting entanglement effects.

The authors conclude that entanglement‑based analyses constitute a novel, model‑independent tool for supernova neutrino physics and that DUNE is uniquely positioned to capitalize on this approach. They suggest future extensions to include collective neutrino‑neutrino effects, Earth‑matter regeneration, and joint analyses with other detectors to fully harness the potential of quantum‑correlation observables in astrophysical neutrino studies.