Performance of the Prototype Station of the IceCube Surface Array Enhancement

TL;DR

This work evaluates Station 0 of the IceCube Surface Array Enhancement (SAE), a hybrid scintillator-radio station deployed along IceTop to improve air-shower detection amid snow-induced attenuation. It details hardware and firmware upgrades that expand dynamic range and up-time, a scalable data-processing pipeline, and a data-driven calibration approach using a Landau-convolved-with-exponential MIP model and temperature correlations. An analysis based on 2023 data shows scintillator reconstructions achieving zenith and solid-angle resolutions around $2.5^ angle$ and $2^ angle$, with better performance for low-energy showers and the potential for further improvements via data-driven timing and lateral-distribution modeling. A key contribution is establishing a Poisson-like fluctuation model for scintillator signals, validated by single-station simulations, which informs future reconstruction enhancements and the planned deployment of additional SAE stations for extended coverage.

Abstract

The prototype station of the Surface Array Enhancement at the IceCube Neutrino Observatory has been taking data in its final design since 2023. This station is part of the planned extension within the footprint of the existing surface array, IceTop. One station consists of 8 scintillator detectors, 3 radio antennas, and a central DAQ. The final upgrade of the scintillation detectors and their firmware at the prototype station has extended the dynamic range and increased the data-taking up-time, thereby expanding the observation window for air showers. This contribution will discuss the performance of the upgraded prototype station after commissioning and its angular resolution capabilities when observing air showers with the scintillation detectors and in coincidence with IceTop. Furthermore, the integration of additional stations during the most recent deployment will be discussed.

Figures (9)

• Figure 1: Layout of the deployed SAE stations at the South Pole. Grey circles indicate IceTop stations corresponding to in-ice strings.
• Figure 2: Flowchart describing the scintillator data processing. The data obtained from the air-shower runs is calibrated using the monitoring information and calibration run information. The pipeline also includes reconstruction of the air-showers observed with scintillation detectors after meeting a defined coincidence condition.
• Figure 3: A histogram of the scaling factors for the three gain channels implemented in the uDAQs obtained from calibration data.
• Figure 4: Temperature Correlation Between Scintillation Detectors and ARO Station (2021–Mid 2022, Summer vs. Winter). The data presented is from 2021 to mid-2022.
• Figure 5: Distribution of reconstructed shower cores overlaid with the scintillator and fieldhub positions.