New paper published in GJI
Takano, T. and Nishida, K. (2024). Estimation of seismometer clock time offsets using Kalman Filter toward accurate seismic velocity change, Geophysical Journal International, ggae322, https://doi.org/10.1093/gji/ggae322
In this study, we examined small changes in the clock time offsets of seismometers at stations around Shinmoe-dake from April 2010 to September 2021 by using the Kalman filter with the maximum likelihood method based on a state-space model from daily stacked cross-correlations of ambient noise. We observed clear clock time offsets at several stations, with clock time errors of up to 0.15 s. We also evaluated the validity of our clock time error estimation by comparing it with the methods used in previous studies.