Prospects for detecting periodic or sharp fast-time features in the supernova neutrino lightcurve with IceCube

TL;DR

The paper addresses the detectability of periodic and sharp fast-time features in the neutrino lightcurves from Galactic core-collapse supernovae using IceCube and the planned IceCube-Gen2, including wavelength-shifting enhancements. It adopts a model-independent approach by parameterizing generic periodic modulations with relative amplitude $A'$ and frequency $f$ in the range $50$–$400$ Hz, and sharp bursts from quark-hadron phase transitions, analyzed via short-time Fourier transform and time-domain amplitude methods. Key results show that IceCube-Gen2 with WLS can detect periodic modulations down to $A'\approx 25\%$ at $5\sigma$ across the Milky Way, versus IceCube's $\approx 50\%$ threshold, and can extend sensitivity to phase-transition signatures to the LMC/SMC; black-hole collapse signatures remain Galactic-limited, while quark-star remnants offer even greater reach. Overall, the work demonstrates substantial gains from IceCube-Gen2 with WLS in extracting physics of core dynamics and dense-matter transitions from CCSN neutrinos, enabling precision studies of Galactic events.

Abstract

Neutrinos produced in core-collapse supernova offer a direct probe into the hydrodynamics and energy transport mechanisms during the collapse and play a pivotal role in the shock revival and success of the supernova explosion. Fast-time features of the neutrino luminosity and energy spectrum encode information about phenomena such as turbulence, convection, shock revival and potential quark-hadron phase transitions. In this study, we explore the detection capabilities of large-volume neutrino telescopes with a focus on IceCube and the planned extension IceCube-Gen2. Furthermore, we consider the effect on the detection sensitivity from wavelength shifters through enhanced light collection. A variety of models predict periodic fast-time features in supernova light curves; to quantify their detectability without relying on specific models, we investigate the detector response to a generic parameterisation of such features. We find that independent of feature frequency, IceCube-Gen2 instrumented with wavelength shifters has sensitivity to weaker modulations ($>25\%$ amplitude) as compared to only the strongest modulations ($>50\%$ amplitude) with IceCube. In addition, we examine the sensitivity of the neutrino lightcurve to sharp features from a quark-hadron phase transition. Phase transitions leading to a quark star remnant are detectable with IceCube at $5σ$ up to the edge of the Galaxy, and throughout the Small Magellanic Cloud with IceCube-Gen2 equipped with wavelength-shifters. In contrast, models collapsing into a black hole are observable only within the Galaxy, covering $41\%$ of the CCSNe population for IceCube and nearly all ($91\%$) for IceCube-Gen2 complemented by wavelength shifters. These results highlight the potential of IceCube-Gen2 for detecting Galactic sources more reliably and with greater reach.

Figures (2)

• Figure 1: Frequency averaged $5\sigma$ detection horizon as a function of the relative amplitude $A'$ of the generic fast-time feature for the detector geometries from Tab. \ref{['tab:detector']}. The error bands indicate the 68% containment interval. The right y-axis indicates the Galactic CCSN coverage following the parametrisation from Ref. Adams:2013rate.
• Figure 2: Detection significance $\xi$ as a function of progenitor distance $d$ for the RDF-1.7 quark-hadron phase transition model for the detector configurations from Tab. \ref{['tab:detector']}. The error bands indicate the 68% containment interval. We also indicate the Galactic CCSN coverage from Ref. Adams:2013rate on the top axis.