Speaker
Description
The detection of coherent elastic neutrino–nucleus scattering (CEvNS) is one of the primary research topics in contemporary neutrino experiments, as its observation provides critical insights not only into the Standard Model but also into physics beyond the Standard Model, such as non-standard neutrino interactions, and establishes the neutrino floor relevant for dark matter searches. Consequently, extensive efforts to observe CEvNS are being pursued worldwide.
The NEON experiment is a reactor-based CEvNS search employing NaI(Tl) crystal detectors. The detector system consists of six NaI(Tl) crystals with a total mass of 16.5 kg. These crystals achieve an average light yield of 25.6 photoelectrons per keV, enabling low-energy analyses down to the sub-keV region. The detector is installed at a distance of 23.7 m from the Hanbit Unit-6 reactor core in Yeonggwang, Korea. Data taking began in April 2022, and to date, the experiment has accumulated 860 days of reactor-on data and 223 days of reactor-off data under stable operating conditions.
For CEvNS detection in the NEON experiment, effective discrimination of scintillation-only events from PMT-induced noise and phosphorescence-related events is essential to achieve a sufficiently low analysis threshold. To address this challenge, a deep-learning–based event selection strategy has been developed using waveform-structure information and pulse shape discrimination (PSD) parameters. This method enables an analysis threshold of 5 photoelectrons, providing adequate sensitivity for the CEvNS search.
By comparing the event rates between reactor-on and reactor-off data after event selection, the NEON experiment aims to identify CEvNS interactions on sodium nuclei. In this presentation, we report the details of our analysis and preliminary results of the CEvNS search based on NEON experimental data.
| Main Contribution topic | Direct detection |
|---|---|
| Secondary contribution topic | Axion / Sterile |