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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…

High Energy Astrophysical Phenomena · Physics 2023-03-03 Hyunwook Ro , Kunwoo Yi , Yuzhu Cui , Motoki Kino , Kazuhiro Hada , Tomohisa Kawashima , Yosuke Mizuno , Bong Won Sohn , Fumie Tazaki

We report new results from an HST archival program to study proper motions in the optical jet of the nearby radio galaxy M87. Using over 13 years of archival imaging, we reach accuracies below 0.1c in measuring the apparent velocities of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Eileen T. Meyer , W. B. Sparks , J. A. Biretta , Jay Anderson , Sangmo Tony Sohn , Roeland P. van der Marel , Colin Norman , Masanori Nakamura

The central radio source in M87 provides the best opportunity to study jet formation because it has a large angular size for the gravitational radius of the black hole and has a bright jet that is well resolved by VLBI observations. We…

High Energy Astrophysical Phenomena · Physics 2018-03-28 R. Craig Walker , Phillip E. Hardee , Frederick B. Davies , Chun Ly , William Junor

We study the kinematics of ridge lines on the pc-scale jet of the active galactic nucleus BL Lac. We show that the ridge lines display transverse patterns that move superluminally downstream, and that the moving patterns are analogous to…

M87 is the best source in which to study a jet at high resolution in gravitational units because it has a very high mass black hole and is nearby. The angular size of the black hole is second only to Sgr A*, which does not have a strong…

High Energy Astrophysical Phenomena · Physics 2016-10-28 R. Craig Walker , Philip E. Hardee , Fred Davies , Chun Ly , William Junor , Florent Mertens , Andrei Lobanov

We describe a 2.5D MHD simulation describing the evolution of cool jets triggered by initial vertical velocity perturbations in the solar chromosphere. We implement random velocity pulses of amplitude 20-50 km/s between 1 Mm and 1.5 Mm,…

Solar and Stellar Astrophysics · Physics 2023-06-26 Abhishek K. Srivastava , Balveer Singh

The nearby radio galaxy M87 offers a unique opportunity to explore the connections between the central supermassive black hole and relativistic jets. Previous studies of the inner region of M87 revealed a wide opening angle for the jet…

We report the initial results of our high-cadence monitoring program on the radio jet in the active galaxy M87, obtained by the KVN and VERA Array (KaVA) at 22 GHz. This is a pilot study that preceded a larger KaVA-M87 monitoring program,…

We present full-track high-resolution radio observations of the jet of the galaxy M87 at 8 and 15 GHz. These observations were taken over three consecutive days in May 2009 using the Very Long Baseline Array (VLBA), one antenna of the Very…

Astrophysics of Galaxies · Physics 2023-10-31 A. S. Nikonov , Y. Y. Kovalev , E. V. Kravchenko , I. N. Pashchenko , A. P. Lobanov

We investigate the magnetic field configuration of the M87 jet at arc-second scales by using archival polarimetric VLA data at 8, 15, 22 and 43 GHz. By stacking images over three years in order to enhance the sensitivity, we reveal, for the…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-31 J. C. Algaba , K. Asada , M. Nakamura

The velocity field of the M87 jet from milli-arcsecond (mas) to arcsecond scales is extensively investigated together with new radio images taken by EVN observations. We detected proper motions of components located at between 160 mas from…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Keiichi Asada , Masanori Nakamura , Akihiro Doi , Hiroshi Nagai , Makoto Inoue

One of the most intriguing open questions of today's astrophysics is the one concerning the location and the mechanisms for the production of MeV, GeV, and TeV gamma-rays in AGN jets. M87 is a privileged laboratory for a detailed study of…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-17 G. Giovannini , C. Casadio , M. Giroletti , M. Beilicke , A. Cesarini , H. Krawczynski

M87 is one of the best available source for studying the AGN jet-launching region. To enrich our knowledge of this region, with quasi-simultaneous observations using VLBA at 22, 43 and 86 GHz, we capture the images of the radio jet in M87…

Astrophysics of Galaxies · Physics 2019-11-01 Wei Zhao , Xiaoyu Hong , Tao An , Xiaofeng Li , Xiaopeng Cheng , Fang Wu

One of the most intriguing open questions of today's astrophysics is the jet physical properties and the location and the mechanisms for the production of MeV, GeV, and TeV gamma-rays in AGN jets. M87 is a privileged laboratory for a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 G. Giovannini , C. Casadio , M. Giroletti , M. Beilicke , A. Cesarini , H. Krawczynski

We study the kinematics of the M87 jet using the first year data of the KVN and VERA Array (KaVA) large program, which has densely monitored the jet at 22 and 43 GHz since 2016. We find that the apparent jet speeds generally increase from…

New high-resolution Very Long Baseline Interferometer observations of the prominent jet in the M87 radio galaxy show a persistent triple-ridge structure of the transverse 15-GHz profile with a previously unobserved ultra-narrow central…

High Energy Astrophysical Phenomena · Physics 2017-08-29 Denis Nikolaevich Sob'yanin

VLBA and Global VLBI observations of M87 at 43 GHz, some new and some previously published, are used to study the structural evolution of the jet with a spatial resolution of under 100 Schwarzschild radii. The images, taken between 1999 and…

Astrophysics · Physics 2011-02-11 Chun Ly , R. Craig Walker , William Junor

Motivated by the measured velocity profile of the M87 jet using the KVN and VERA Array (KaVA) by Park et al. indicating that the starting position of the jet acceleration is farther from the central engine of the jet than predicted in…

High Energy Astrophysical Phenomena · Physics 2022-11-16 Motoki Kino , Masaaki Takahashi , Tomohisa Kawashima , Jongho Park , Kazuhiro Hada , Hyunwook Ro , Yuzhu Cui

The structure and dynamics of the M87 jet from sub-milli-arcsec to arcsecond scales are continuously examined. We analysed the VLBA archival data taken at 43 and 86 GHz to measure the size of VLBI cores. Millimeter/sub-mm VLBI cores are…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Masanori Nakamura , Keiichi Asada

In this article, we report the multiwavelength and multiview observations of transverse oscillations of two loop strands induced by a jet-related, confined flare in active region NOAA 13056 on 11 July 2022. The jet originates close to the…

Solar and Stellar Astrophysics · Physics 2025-04-28 Musheng Lin , Ya Wang , Liheng Yang , Jie Chen , Wenwei Pan , Shuyue Li , Qingmin Zhang
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