Hybrid multi-mode atmospheric coefficients of secondary cosmic muons measured with portable muon telescope at DEASA, Agra

Abstract This study examines how atmospheric conditions - pressure, temperature, and humidity influence cosmic ray (CR) muons using daily and monthly data collected with portable muon detectors at the Dayalbagh Educational Institute, Agra, from 2016 onward. Two detector setups were used, with solid angles of 0.06 sr and 0.15 sr, both maintaining a 15 cm separation. The first setup collected data in 2019, before COVID-19, and the second recorded data in 2022, post-COVID-19. The study examines how atmospheric factors such as pressure, temperature, and humidity influence cosmic ray (CR) muon intensity over different time scales, including daily and monthly variations. The results show that both pressure and temperature have a negative effect on muon intensity, whereas relative humidity has a positive effect. A comparison with Thailand neutron monitor data indicates that neutron-muon flux correlations with a weak correlation coefficient 0.06\ %/mbar in 2019. and strong correlation 0.16\ %/mbar in 2022. These changes can be associated with Solar Cycle 24 (low solar activity, higher muon flux) to Solar Cycle 25( increasing solar activity, stronger solar modulation). These findings highlight the necessity of accurate atmospheric corrections in cosmic ray research and enhance our understanding of how environmental factors influence muon flux variations.