A4 Article in conference proceedings
New Evidence for DM-like Anomalies in neutron multiplicity spectra (2024)

Trzaska, W. H., Barzilov, A., Enqvist, T., Jędrzejczak, K., Kasztelan, M., Kuusiniemi, P., Loo, K., Orzechowski, J., Słupecki, M., Szabelski, J., & Ward, T. (2024). New Evidence for DM-like Anomalies in neutron multiplicity spectra. In V. Mokina (Ed.), TAUP2023 : XVIII International Conference on Topics in Astroparticle and Underground Physics (Article 083). Sissa. POS Proceedings of Science, 441. https://doi.org/10.22323/1.441.0083

JYU authors or editors

Publication details

All authors or editors: Trzaska, Wladyslaw Henryk; Barzilov, Alex; Enqvist, Timo; Jędrzejczak, Karol; Kasztelan, Marcin; Kuusiniemi, Pasi; Loo, Kai; Orzechowski, Jerzy; Słupecki, Maciej; Szabelski, Jacek; et al.

Parent publication: TAUP2023 : XVIII International Conference on Topics in Astroparticle and Underground Physics

Parent publication editors: Mokina, Valentyna

Place and date of conference: Vienna, Austria, 28.8.2023-1.9.2023

Journal or series: POS Proceedings of Science

eISSN: 1824-8039

Publication year: 2024

Publication date: 22/03/2024

Number in series: 441

Article number: 083

Publisher: Sissa

Publication country: Italy

Publication language: English

DOI: https://doi.org/10.22323/1.441.0083

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/94696

Publication is parallel published: https://arxiv.org/abs/2311.14385

Abstract

Subterrestrial neutron spectra show weak but consistent anomalies at multiplicities ~100 and above. The origin of the excess events remains ambiguous, but, in principle, it could be a signature of Dark Matter WIMP annihilation-like interaction with a massive Pb target. However, since the results of the available measurements are below the 5-sigma discovery level, and the observed anomalous structures are on a significant muon-induced background, an independent verification at even greater depth is needed. For that purpose, we have launched NEMESIS 1.4 – a new dedicated experiment consisting of an 1134 kg Pb target and 14 He-3 detectors with PE moderators and a fully digital readout. NEMESIS 1.4 has been taking data at the deepest level (1.4 km, 4000 m.w.e.) of the Pyhäsalmi mine, Finland, since November 2022. We describe the idea behind the new setup, compare the first results with the previous data and Monte Carlo simulations, and give the outlook for further research. If the existence of the anomalies is unambiguously confirmed and the model interpretation positively verified, this will be the first Indirect Detection of Dark Matter in the laboratory.

Keywords: dark matter; research equipment; detectors; astrophysics; particle physics

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2024

Preliminary JUFO rating: 0