Low energy event reconstruction in IceCube DeepCore

Abstract

The reconstruction of event-level information, such as the direction or energy of a neutrino interacting in IceCube DeepCore, is a crucial ingredient to many physics analyses. Algorithms to extract this high level information from the detector’s raw data have been successfully developed and used for high energy events. In this work, we address unique challenges associated with the reconstruction of lower energy events in the range of a few to hundreds of GeV and present two separate, state-of-the-art algorithms. One algorithm focuses on the fast directional reconstruction of events based on unscattered light. The second algorithm is a likelihood-based multipurpose reconstruction offering superior resolutions, at the expense of larger computational cost.

Search for sub-TeV Neutrino Emission from Novae with IceCube-DeepCore

“…Additionally, searching for neutrino emission on longer timescales, especially when stacking, becomes difficult with low-energy events. There are already improvements being made to low-energy reconstructions with IceCube-DeepCore (Abbasi et al 2022b), and reconstructions with next-generation observatories have the promise of being even better due to an enhanced understanding of systematic uncertainties. Combining these improvements-enhanced effective area at the lowest energies to boost signal and better background discrimination from better event reconstructions that allow for longer integration times-have the promise of greatly enhancing sensitivity to low-energy transients such as novae.…”

Neutrino Mass Ordering with IceCube DeepCore

“…The final level event rates of the sample can be seen in Table 1. Figure 3 shows the reconstruction resolution for ν µ CC events, which dominate the DeepCore signal as can be seen in Figure 1, as a function of the true neutrino energy [9]. Since the NMO sensitivity for DeepCore lies at energies below 15 GeV, reconstruction is the main challenge in this analysis as it proves difficult to precisely reconstruct the neutrino energy in this region.…”

IceCube – Neutrinos in Deep Ice

“…For instance, the method described in Ref. [13] is based on sophisticated photon ray tracing to approximate the full reconstruction likelihood, and can reconstruct all event topologies, but is limited to the GeV energy range. Beyond the GeV scale, similar approaches are followed that typically target a specific type of event [6,14].…”