Observing the Time Evolution of the Multi-Component Nucleus of 3C\,84

Abstract

The advent of global mm-band Very Long Baseline Interferometry (VLBI) in recent years has finally revealed the morphology of the base of the two most prominent nearby, bright, extragalactic radio jets in M\,87 and 3C\,84. The images are quite surprising considering the predictions of jet theory and current numerical modeling. The jet bases are extremely wide compared to expectations and the nucleus of 3C\,84 is very complicated. It appears as a double in 86\,GHz observations with 50\,$\mu$as resolution and a triple nucleus with 30\,$\mu$as resolution with space-based VLBI by RadioAstron at 22\,GHz. What is even odder is that the double and triple are arranged along an east-west line that is approximately orthogonal to the north-south large scale jet on 150\,$\mu$as $-$ 4\,mas scales. We explore the emergence of an (east-west) double nucleus in the lower resolution 43\,GHz Very Long Baseline Array (VLBA) imaging from August 2018 to April 2020. The double is marginally resolved. We exploit the east-west resolution associated with the longest baselines, $\sim 0.08$\,mas, to track a predominantly east-west separation speed of $\approx 0.086\pm 0.008$\,c. We estimate that the observed mildly relativistic speed persists over a de-projected distance of $\sim 1900-9800$ times the central, supermassive black hole, gravitational radius ($\sim 0.3-1.5$\,lt-yrs) from the point of origin.

To appear in ApJ

References in corpus (7)

• Kinematics of Parsec-Scale Jets of Gamma-Ray Blazars at 43~GHz within the VLBA-BU-BLAZAR Program
• RadioAstron -- a Telescope with a Size of 300 000 km: Main Parameters and First Observational Results
• A Global 86GHz VLBI Survey of Compact Radio Sources
• A strong radio brightening at the jet base of M87 during the elevated very-high-energy gamma-ray state in 2012
• Discovery of a new subparsec counterjet in NGC 1275: the inclination angle and the environment
• Rapid Gamma-ray variability of NGC 1275
• Constraints on Black Hole Jet Models Used As Diagnostic Tools of Event Horizon Telescope Observations of M87

Cited by in corpus (2)

• Pinpointing the jet apex of 3C 84
• Ordered magnetic fields around the 3C 84 central black hole