Lost in the curve: Investigating the disappearing knots in the blazar 3C 454.3

Efthalia Traianou; Thomas P. Krichbaum; José L. Gómez; Rocco Lico; Georgios Filippos Paraschos; Ilje Cho; Eduardo Ros; Guang-Yao Zhao; Ioannis Liodakis; Rohan Dahale; Teresa Toscano; Antonio Fuentes; Marianna Foschi; Carolina Casadio; Nicholas MacDonald; Jae-Young Kim; Olivier Hervet; Svetlana Jorstad; Andrei P. Lobanov; Jeffrey Hodgson; Ioannis Myserlis; Ivan Agudo; Anton J. Zensus; Alan P. Marscher

arXiv · 2312.15556

Lost in the curve: Investigating the disappearing knots in the blazar 3C 454.3

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Abstract

One of the most well-known extragalactic sources in the sky, quasar 3C 454.3, shows a curved parsec-scale jet that has been exhaustively monitored with very-long-baseline interferometry (VLBI) over the recent years. In this work, we present a comprehensive analysis of four years of high-frequency VLBI observations at 43 GHz and 86 GHz, between 2013-2017, in total intensity and linear polarization. The images obtained from these observations enabled us to study the jet structure and the magnetic field topology of the source on spatial scales down to 4.6 parsec in projected distance. The kinematic analysis reveals the abrupt vanishing of at least four new superluminal jet features in a characteristic jet region (i.e., region C), which is located at an approximate distance of 0.6 milliarcseconds from the VLBI core. Our results support a model in which the jet bends, directing the relativistic plasma flow almost perfectly toward our line of sight, co-spatially with the region where components appear to stop.

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Efthalia Traianou, Thomas P. Krichbaum, José L. Gómez, Rocco Lico, Georgios Filippos Paraschos, Ilje Cho, Eduardo Ros, Guang-Yao Zhao, Ioannis Liodakis, Rohan Dahale, Teresa Toscano, Antonio Fuentes, Marianna Foschi, Carolina Casadio, Nicholas MacDonald, Jae-Young Kim, Olivier Hervet, Svetlana Jorstad, Andrei P. Lobanov, Jeffrey Hodgson, Ioannis Myserlis, Ivan Agudo, Anton J. Zensus, Alan P. Marscher. 2023-12-24. Lost in the curve: Investigating the disappearing knots in the blazar 3C 454.3. https://arxiv.org/abs/2312.15556

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