Table 2.
Best-fit values of the sinusoidal and linear drift model derived from a χ2 fit to the observed data.
| Parameter | Sinusoidal model up to 2012 | Sinusoidal model up to 2019 | Linear drift model up to 2019 |
|---|---|---|---|
| θ0 | (62.9 ± 0.8) ° | (63.1 ± 0.8)° | 62.4 ± 0.2° |
| β | (0.4 ± 0.1))°/yr | (0.5 ± 0.1)°/yr | 0.2 ± 0.2°/yr |
| A | (6.9 ± 0.8)° | (6.9 ± 0.8)° | – |
| T | (6.7 ± 0.2) yr | (6.9 ± 0.2) yr | – |
| 1996 − t0 | −(3.06 ± 0.24) yr | ( − 3.15 ± 0.25) yr | – |
Notes. The first column shows the model parameters for the different models and data used. The second column shows the best-fit values derived from fitting a sinusoidal model (Eq. (1)) to the data up to 2012, i.e., based on the Martí-Vidal et al. (2011) and Alberdi et al. (2013) data. The third column shows values derived from the sinusoidal model, including the new data from 2017 and 2019. The third column shows the best values of the linear drift model (Eq. (A.1)), including the new data from 2017 and 2019.
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