Abstract
Based on the maximum likelihood method, an optimal algorithm has been developed for detecting the 2S1 mode triplet in seismic noise. The algorithm allows to estimate the degenerate frequency and the splitting parameter \(b\), which determines the range of the mode singlets from each other, as well as to estimate the detection reliability (the false alarm probability). The algorithm was tested on synthetic data. A synthetic signal with an amplitude of about 2 nGal and a signal-to-noise ratio of 10–2 was detected over noise background and the calculated estimates was fully agree with the specified signal model. The tests have shown that the algorithm is very effective. The algorithm was applied to study the 2S1 mode after the significant earthquake in Chile on February 27, 2010. The records of the 22 superconducting gravimeters from IGETS network were used. The degenerate frequency of the 2S1 mode and the Coriolis splitting parameter were estimated, and triplet frequencies were calculated.
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This work was supported by the Interdisciplinary Scientific and Educational School “Fundamental and Applied Space Research” of Moscow University.
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Milyukov, V.K., Vinogradov, M.P. Assessment of the 2S1 Mode Triplet Based on IGETS Data After 2010 Chile Earthquake. Pure Appl. Geophys. 180, 735–746 (2023). https://doi.org/10.1007/s00024-022-03158-x
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DOI: https://doi.org/10.1007/s00024-022-03158-x