The Astrophysical Journal (Jan 2023)
Correlation Analysis between OJ 287 Radio Jet Observables
Abstract
We collected the archival data of blazar OJ 287 from heterogeneous very long baseline interferometry monitoring programs at 2.3, 8.6, 15, and 43 GHz. The data reduction and observable extraction of those multiband, multiepoch observations are batch-processed consistently with our automated pipeline. We present the multivariate correlation analysis on the observables at each band. We employ the cross-correlation function to search the correlations and the Monte Carlo technique to verify the certainty of correlations. Several correlations are found. The foremost findings are the correlations between the core flux density and the jet position angles on different scales, which validated the plausible predictions of the jet with precession characteristics. Meanwhile, there is a variation in the offset between the core electric vector position angle and the inner-jet position angle over time at 15 and 43 GHz.
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