The fundamental plane of black hole activity for strong radio black hole sources

Abstract

AbstractIt is still controversial whether the x‐ray emissions of strong radio black hole sources (e.g., blazars and FR Is) are from a jet‐dominated flow or from an accretion disc. Previous studies have suggested that the radio–x‐ray correlation is clearly different when the x‐ray luminosity is higher or lower than a critical value, , where is the Eddington luminosity. When the black hole transient sources stay in quiescent state (), the radio–x‐ray correlation presented a steeper slope (). In this work, we constructed a strong radio sample, including blazars and FR Is with a wide x‐ray luminosity distribution () to re‐explore this issue. An obvious change in radio–x‐ray correlations is not found when the x‐ray luminosity and . And the radio–x‐ray correlation and the fundamental plane of black hole activity for strong radio sources follow a slope with . These results imply x‐ray emissions of strong radio black hole sources have similar physics and can be well explained by a jet‐dominated flow.