A4 Article in conference proceedings
High-multiplicity muon events observed with EMMA array (2020)

Trzaska, W. H., Bezrukov, L., Enqvist, T., Inzhechik, L., Joutsenvaara, J., Kuusiniemi, P., Loo, K., Lubsandorzhiev, B., & Słupecki, M. (2020). High-multiplicity muon events observed with EMMA array. In TAUP 2019 : 16th International Conference on Topics in Astroparticle and Underground Physics (Article 012085). IOP Publishing. Journal of Physics: Conference Series, 1468. https://doi.org/10.1088/1742-6596/1468/1/012085

JYU authors or editors

Publication details

All authors or editors: Trzaska, Wladyslaw Henryk; Bezrukov, Leonid; Enqvist, Timo; Inzhechik, Lev; Joutsenvaara, Jari; Kuusiniemi, Pasi; Loo, Kai; Lubsandorzhiev, Bayarto; Słupecki, Maciej

Parent publication: TAUP 2019 : 16th International Conference on Topics in Astroparticle and Underground Physics

Place and date of conference: Toyama, Japan, 9.-13.9.2019

Journal or series: Journal of Physics: Conference Series

ISSN: 1742-6588

eISSN: 1742-6596

Publication year: 2020

Number in series: 1468

Article number: 012085

Publisher: IOP Publishing

Publication country: United Kingdom

Publication language: English

DOI: https://doi.org/10.1088/1742-6596/1468/1/012085

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/68376


High-multiplicity data, collected with a segmented scintillator array of the cosmic-ray experiment EMMA (Experiment with Multi-Muon Array), is presented for the first time. The measurements were done at the depth of 75 meters (210 m.w.e.) in the Pyhäsalmi mine in Finland. EMMA uses two types of detectors: drift chambers and plastic scintillation detectors. The presented data were acquired over the period between December, 2015 and April, 2018 using 128-800 plastic scintillator pixels probing the fiducial area of ˜100 m2. The results are being interpreted in terms of CORSIKA simulations. Several events with densities in excess of 10 muons per m2 were observed. At the next stage of the analysis, the high-multiplicity events will be matched with precision tracking data extracted from the multi-layer drift chambers of EMMA. Observation of high-density muon bundles was first reported by the LEP experiments: DELPHI, L3+C, and ALEPH. More recently, the ALICE experiment at CERN has provided new cosmic-ray results together with improved interpretation benefiting from the updated cross section values extracted from LHC results. While the tracking performance of ALICE is superior to EMMA, the duration of ALICE cosmic-ray measurements is very limited. Over the period of 2010–2018 the total exposure was only 93 days while EMMA, having a similar overburden provides a larger footprint and collects data continuously.

Keywords: particle physics; astrophysics; cosmic radiation

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2020

JUFO rating: 1

Last updated on 2022-20-09 at 14:31