Next Article in Journal / Special Issue
Magnetic Dissipation in Relativistic Jets
Previous Article in Journal / Special Issue
Microscopic Processes in Global Relativistic Jets Containing Helical Magnetic Fields
Article Menu

Export Article

Open AccessArticle
Galaxies 2016, 4(4), 39; doi:10.3390/galaxies4040039

Resolving the Base of the Relativistic Jet in M87 at 6Rsch Resolution with Global mm-VLBI

Max Planck Institut für Radioastronomie, Auf dem Hügel 69, Bonn D-53121, Germany
Institut de Radio Astronomie Millimétrique, 300 rue de la Piscine, Domaine Universitaire, Saint Martin d’Héres 38406, France
National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801, USA
Author to whom correspondence should be addressed.
Academic Editors: Jose L. Gómez, Alan P. Marscher and Svetlana G. Jorstad
Received: 15 July 2016 / Revised: 22 September 2016 / Accepted: 23 September 2016 / Published: 30 September 2016
(This article belongs to the Special Issue Blazars through Sharp Multi-wavelength Eyes)
View Full-Text   |   Download PDF [1526 KB, uploaded 30 September 2016]   |  


M87 is one of the nearest radio galaxies with a central Super-Massive Black Hole (SMBH) and a prominent relativistic jet. Due to its close distance to the observer and the large SMBH mass, the source is one of the best laboratories to obtain strong observational constraints on the theoretical models for the formation and evolution of the AGN jets. In this article, we present preliminary results from our ongoing observational study about the innermost jet of M87 at an ultra-high resolution of ∼50 μ as achieved by the Global Millimeter-Very Long Baseline Interferometry Array (GMVA). The data obtained between 2004 and 2015 clearly show limb-brightened jets at extreme resolution and sensitivity. Our preliminary analysis reveals that the innermost jet expands in an edge-brightened cone structure (parabolic shape) but with the jet expansion profile slightly different from the outer regions of the jet. Brightness temperatures of the Very Long Baseline Interferometry (VLBI) core obtained from cm- to mm-wavelengths show a systematic evolution, which can be interpreted as the evolution as a function of distance from the BH. We also adopt an alternative imaging algorithm, Bi-Spectrum Maximum Entropy Method (BSMEM), to test reliable imaging at higher angular resolution than provided by the standard CLEAN method (i.e., super-resolution). A demonstration with a VLBA 7 mm example data set shows consistent results with a near-in-time 3 mm VLBI image. Application of the method to the 2009 GMVA data yields an image with remarkable fine-scale structures that have been never imaged before. We present a brief interpretation of the complexity in the structure. View Full-Text
Keywords: galaxies: active; galaxies: jets; galaxies: individual (M87); techniques: interferometric; techniques: image processing galaxies: active; galaxies: jets; galaxies: individual (M87); techniques: interferometric; techniques: image processing

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Kim, J.-Y.; Lu, R.-S.; Krichbaum, T.P.; Bremer, M.; Zensus, J.A.; Walker, R.C.; the M87 collaboration. Resolving the Base of the Relativistic Jet in M87 at 6Rsch Resolution with Global mm-VLBI. Galaxies 2016, 4, 39.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Galaxies EISSN 2075-4434 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top