Global VLBI Images of Gamma-ray Bright Blazars with the GMVA

***Note: This web page is under construction***

Principal Investigators:

Alan Marscher (Boston U.)
Thomas Krichbaum (Max-Planck-Institut für Radioastronomie)


Carolina Casadio, Nicholas MacDonald, Jae-Young Kim, Efthalia Traianou  (MPIfR)
Svetlana Jorstad, Mason Keck
Jeffrey Hodgson, Bong Won Sohn (Korea Astronomy & Space Inst.)
José Luis Gómez, Iván Agudo, Antonio Fuentes (Inst. de Astrofísica de Andalucía)
Michael Bremer (Inst. de Radio Astronomique Millimétrique)

In support of the VLBA-BU-BLAZAR program, we observe selected blazars from the sample with the Global mm-VLBI Array (GMVA) at a wavelength of 3.5 mm (frequency of 86 GHz) 1-2 times per year. This provides higher-resolution images than those at 43 GHz at a wavelength where the jet is less opaque. The series of 43 GHz images reveals the development of the jet of a blazar over time, while the 86 GHz "snapshots" show finer detail at particular times.

Data products available: At this point, only images of selected blazars at selected epochs are available, some in total intensity only and others with linear polarization. At a later stage, this site will post CLEAN model files and calibrated visibility (uv) data files as well, and will expand to include all sources and all epochs since the program started in 2008. The techniques for optimizing the observations and data analysis required years of refinement before the image quality became high enough for scientific applications. The collaboration is now making a concerted effort to apply these techniques retroactively to the entire data set. If you need access to specific data files before they become available here, please contact Alan Marscher (

Note: Multi-frequency flux and optical polarization data from the Boston University blazar monitoring program are available for these objects at individual VLBA-BU-BLAZAR web pages, accessed via

Spectral energy distributions: Full version of paper by K.E. Williamson et al. (2014, Astrophysical Journal, vol.789, article no. 135), including figures and data tables for all blazars studied. The paper, is entitled "Comprehensive Monitoring of Gamma-ray Bright Blazars. I. Statistical Study of Optical, X-ray, and Gamma-ray Spectral Slopes."

List of publications from this program

Note: If you use any of these images or data in a publication, please acknowledge via the statement:
This study makes use of 86 GHz Global mm-VLBI Array (GMVA) data from a collaborative project led by A. Marscher of Boston University and T. Krichbaum of the Max-Planck-Institut für Radioastronomie; see website

Images from the Program (click on the name of the object):

0415+37 (3C111) 0420-014 (OA129)
0430+05 (3C120) 0716+714 0836+710 0851+202 (OJ287)
0954+658 1055+018

1226+023 (3C273) 1253-055 (3C279) 1510-089
1633+382 (4C+38.41) 1641+399 (3C345)
2200+420 (BLLac) 2223-052 (3C446) 2230+114 (CTA102) 2251+158 (3C454.3)

For more information on blazars, see our research page.

Back to the blazar group's home page

Go to the personal web pages of: Alan Marscher ---- Svetlana Jorstad