Transverse Oscillations of the M87 Jet Revealed by KaVA Observations

Bibliographic Details
Title: Transverse Oscillations of the M87 Jet Revealed by KaVA Observations
Authors: Hyunwook Ro, Kunwoo Yi, Yuzhu Cui, Motoki Kino, Kazuhiro Hada, Tomohisa Kawashima, Yosuke Mizuno, Bong Won Sohn, Fumie Tazaki
Source: Galaxies, Vol 11, Iss 1, p 33 (2023)
Publisher Information: MDPI AG, 2023.
Publication Year: 2023
Collection: LCC:Astronomy
Subject Terms: active galactic nuclei (AGN), M87, relativistic jet, very long baseline interferometry (VLBI), oscillation, instability, Astronomy, QB1-991
More Details: Recent VLBI monitoring has found transverse motions of the M87 jet. However, due to the limited cadence of previous observations, details of the transverse motion have not been fully revealed yet. We have regularly monitored the M87 jet at KVN and VERA Array (KaVA) 22 GHz from December 2013 to June 2016. The average time interval of the observation is ∼0.1 year, which is suitable for tracking short-term structural changes. From these observations, the M87 jet is well represented by double ridge lines in the region 2–12 mas from the core. We found that the ridge lines exhibit transverse oscillations in all observed regions with an average period of 0.94±0.12 years. When the sinusoidal fit is performed, we found that the amplitude of this oscillation is an order of ∼0.1 mas, and the oscillations in the northern and southern limbs are almost in phase. Considering the amplitude, it does not originate from Earth’s parallax. We propose possible scenarios of the transverse oscillation, such as the propagation of jet instabilities or magneto-hydrodynamic (MHD) waves or perturbed mass injection around magnetically dominated accretion flows.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2075-4434
Relation: https://www.mdpi.com/2075-4434/11/1/33; https://doaj.org/toc/2075-4434
DOI: 10.3390/galaxies11010033
Access URL: https://doaj.org/article/fd4a755edcc24439b637252ae5b58088
Accession Number: edsdoj.fd4a755edcc24439b637252ae5b58088
Database: Directory of Open Access Journals
More Details
ISSN:20754434
DOI:10.3390/galaxies11010033
Published in:Galaxies
Language:English