Atmospheric charged $$K/\pi $$K/π ratio and measurement of muon annual modulation with a liquid scintillation detector at Soudan

Clicks: 251
ID: 113778
2019
We report a measurement of muon annual modulation in a 12-l liquid scintillation detector with a live-time of more than 4 years at the Soudan Underground Laboratory. Muon minimum ionization in the detector is identified by its observed pulse shape and large energy deposition. The measured muon rate in the detector is $$28.69\pm 2.09$$28.69±2.09 muons per day with a modulation amplitude of ($$2.64\pm 0.07$$2.64±0.07)% and a phase at Jul $$22 \pm 36.2$$22±36.2 days. This annual modulation is correlated with the variation of the effective atmospheric temperature in the stratosphere. The correlation coefficient, $$\alpha _{T}$$αT, is determined to be $$0.898 \pm 0.025$$0.898±0.025. This can be interpreted as a measurement of the atmospheric charged kaon to pion ($$K/\pi $$K/π) ratio of $$0.094^{+0.044}_{-0.061}$$0.094-0.061+0.044 for $$E_{p} > 7$$Ep>7 TeV, consistent with the measurement from the MINOS far detector. To further constrain the value of $$K/\pi $$K/π ratio, a Geant4 simulation of the primary cosmic-ray protons with energy up to 100 TeV is implemented to study the correlation of $$K/\pi $$K/π ratio and the muon annual modulation for muon energy greater than 0.5 TeV. We find out that a charged $$K/\pi $$K/π ratio of 0.1598, greater than the upper bound (0.138) from this work at the production point 30 km above the Earth surface in the stratosphere cannot induce muon annual modulation at the depth of Soudan.
Reference Key
zhang2019theatmospheric Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors C. Zhang;D.-M. Mei;C. Zhang;D.-M. Mei;
Journal the european physical journal c
Year 2019
DOI doi:10.1140/epjc/s10052-019-7344-9
URL
Keywords

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

No comments yet. Be the first to comment on this article.