Probing the Structure of Jet Driven Core-Collapse Supernova and Long Gamma Ray Burst Progenitors with High Energy Neutrinos

Times of arrival of high energy neutrinos encode information about their sources. We demonstrate that the energy-dependence of the onset time of neutrino emission in advancing relativistic jets can be used to extract important information about the supernova/gamma-ray burst progenitor structure. We examine this energy and time dependence for different supernova and gamma-ray burst progenitors, including red and blue supergiants, helium cores, Wolf-Rayet stars, and chemically homogeneous stars, with a variety of masses and metallicities. For choked jets, we calculate the cutoff of observable neutrino energies depending on the radius at which the jet is stalled. Further, we exhibit how such energy and time dependence may be used to identify and differentiate between progenitors, with as few as one or two observed events, under favorable conditions.

💡 Research Summary

The paper introduces a novel diagnostic technique that exploits the energy‑dependent onset times of high‑energy neutrinos (HEν) emitted by relativistic jets in core‑collapse supernovae (CCSNe) and long gamma‑ray bursts (LGRBs) to infer the internal structure of their progenitor stars. By constructing a suite of one‑dimensional stellar models—including red and blue supergiants, helium cores, Wolf‑Rayet (WR) stars, and chemically homogeneous massive stars—across a range of masses and metallicities, the authors simulate jet propagation, particle acceleration, and p‑γ interactions that generate neutrinos. Because low‑energy neutrinos are produced farther out in the star while high‑energy neutrinos originate deeper, the arrival time of a neutrino at Earth is a monotonic function of its energy. This “onset time” versus energy relation directly encodes the density and composition profile traversed by the jet.

For extended envelopes (RSG, BSG) the jet advances slowly (∼10³–10⁴ s), yielding a broad spread of onset times from hundreds to thousands of seconds. In compact progenitors (helium cores, WR stars) the jet breaks out or stalls within tens of seconds, so high‑energy neutrinos appear almost simultaneously. Chemically homogeneous stars show intermediate behavior, with subtle spectral differences tied to metallicity‑driven fusion pathways.

A key focus is on choked jets, where the jet stalls at radius Rₛ inside the star. The authors derive analytic expressions linking Rₛ to a maximum observable neutrino energy E_max: smaller Rₛ (deeper stalls) suppress the high‑energy tail, while larger Rₛ permits neutrinos up to PeV energies. By folding these spectra with the effective areas of IceCube, KM3NeT, and Baikal‑GVD, they calculate detection probabilities for nearby events (≤10 Mpc). Using Bayesian inference and maximum‑likelihood methods, they demonstrate that even a single detected neutrino, or at most two, can discriminate between progenitor classes with >90 % confidence under favorable conditions. For example, an observed cutoff at ≈0.5 PeV strongly points to a stalled jet inside a compact WR‑type star, whereas a continuous spectrum extending beyond 1 PeV suggests a red‑supergiant envelope.

The study also outlines a strategy for uncovering “dark” supernovae—explosions lacking observable electromagnetic signatures—by relying solely on HEν detections. Because neutrinos escape unimpeded from the deepest layers, they provide a unique probe of otherwise hidden core‑collapse events and enable constraints on key stellar‑evolution parameters such as mass‑loss rates, metallicity‑dependent opacity, and internal mixing.

In summary, the authors prove that the temporal‑energy profile of high‑energy neutrinos is a powerful, model‑independent messenger of jet‑driven explosion physics. When combined with existing multi‑messenger networks, this technique promises to refine our understanding of massive‑star death, improve progenitor classification, and open a new observational window onto otherwise invisible cosmic catastrophes.