Time Lag in Diurnal Correlations vs. Asymptotic Longitudinal Separation
Issued Date
2024-09-27
Resource Type
eISSN
18248039
Scopus ID
2-s2.0-85212294096
Journal Title
Proceedings of Science
Volume
444
Rights Holder(s)
SCOPUS
Bibliographic Citation
Proceedings of Science Vol.444 (2024)
Suggested Citation
Sonsrettee W., Nuntiyakul W., Seripienlert A., Ruffolo D., Evenson P., Saiz A., Kittiya A., Oh S., Munakata K. Time Lag in Diurnal Correlations vs. Asymptotic Longitudinal Separation. Proceedings of Science Vol.444 (2024). Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/102510
Title
Time Lag in Diurnal Correlations vs. Asymptotic Longitudinal Separation
Corresponding Author(s)
Other Contributor(s)
Abstract
The correlation between two neutron monitor count rates vs. time lag τ can be fit by the sum of a linear function of |τ| (a triangular function of τ), representing temporal correlation, and a sinusoid with phase ϕ, representing the diurnal correlation associated with cosmic ray anisotropy at directional separation ϕ. Comparing 1-minute count rates from pairs of neutron monitors with similar cutoff rigidities but different asymptotic longitudes, we measure ϕ from the diurnal correlation between count rates and find this to be closely related to the separation of asymptotic longitudes of the primary cosmic rays. We propose that this technique provides an alternative measurement of the diurnal anisotropy at various cutoff rigidities disentangled from temporal variations.