GPS-Synchronized Monitoring of Supernova Bursts in PandaX-4T: Enabling a Neutrino Trigger for Multi-Messenger Astronomy

Abstract

The landmark detection of neutrinos from SN 1987A marked the dawn of a new era in astrophysics, unequivocally establishing them as indispensable probes for investigating stellar evolution and supernova dynamics. Today, supernova burst neutrinos can be observed through coherent elastic neutrino-nucleus scattering in tonne-scale liquid xenon detectors designed for direct dark matter detection. Capitalizing on this capability, we have developed and deployed a real-time supernova monitoring system for the PandaX-4T experiment. This system incorporates a GPS module providing millisecond-level timing precision, achieves a low false-alarm rate, and maintains high sensitivity to galactic supernova events. This robust methodology is directly scalable and slated for implementation in the next-generation PandaX-20T experiment.

Figures (4)

• Figure 1: Schematic diagram of the PandaX-4T's GPS-based timing system.
• Figure 2: Schematic diagram of SN online monitoring system in PandaX-4T.
• Figure 3: Typical timing distributions of the detected supernova neutrino events from the distance of 168 pc (top left) and 10 kpc (top right). Data points are produced by simulations and the red lines are the fit results. The fitted onset times relative to the truth time in 10,000 simulated measurements are shown in the bottom panels. The resulting onset time measurement exhibits a variation of $[-2.7, 2.4]$ ms and $[-0.38, 0.11]$ s relative to zero for 168 pc and 10 kpc, respectively, within a 68% confidence level (C.L.).
• Figure 4: Detection probability of the SN explosions as a function of distance using the Garching model with $M_{p}=27~M_{\odot}$ for PandaX-4T (black) and PandaX-20T (red). The corresponding false alert rate is twice a month in PandaX-4T.