European VLBI Network

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European VLBI Network
Location Various sites across Europe and the rest of the world
Wavelength 18cm, 6cm, 3.6cm, 1.3cm and 0.7cm
Built 1980
Angular resolution 5, 1.5, 1, 0.3 or 0.15 milliarcseconds (depending on observing frequency)
Website http://www.evlbi.org

The European VLBI Network (EVN) was formed in 1980 by a consortium of five of the major radio astronomy institutes in Europe (the European Consortium for VLBI). Since 1980, the EVN and the Consortium has grown to include 9 institutes with 12 radio telescopes in 8 western European countries as well as associated institutes with telescopes in Italy, Poland, Russia, Ukraine, China and South Africa. Proposals for additional telescope in Spain are under consideration, and furthermore, the EVN can be linked to the 7-element Jodrell Bank MERLIN interferometer in the UK and to the US Very Long Baseline Array (VLBA) to create a "global network". In 1993 the Joint Institute for VLBI in Europe (JIVE) was created, with the Netherlands Foundation for Research in Astronomy (Dwingeloo) acting as the host institute. It will provide both scientific user support and a correlator facility. Very Long Baseline Interferometry (VLBI) achieves ultra-high angular resolution and is a multi-disciplinary technique e.g. imaging of extragalactic radio sources, geodesy and astrometry.

EVN Telescopes[edit]

The EVN network consists of 19 telescopes:[1]

Name Dish Size Location Operated by
Effelsberg 100-m Radio Telescope 100 metres Effelsberg, Germany Max Planck Institute for Radio Astronomy
Westerbork Synthesis Radio Telescope 12 x 25 metres Westerbork, Netherlands ASTRON
Sardinia Radio Telescope 64 metres San Basilio, Italy Istituto Nazionale di Astrofisica
Lovell Telescope 76 metres Goostrey, Cheshire, United Kingdom Jodrell Bank Observatory
Cambridge 32 metres 32 metres Mullard Radio Astronomy Observatory, United Kingdom Jodrell Bank Observatory
Mark II 25 metres Goostrey, Cheshire, United Kingdom Jodrell Bank Observatory
Medicina Radio Observatory 32 metres Medicina, Italy Istituto Nazionale di Astrofisica
Onsala Space Observatory 25 metres and 20 metres Onsala, Sweden Chalmers University of Technology
Noto Radio Observatory 32 metres Noto, Italy Istituto Nazionale di Astrofisica
Toruń Centre for Astronomy 32 metres Toruń, Poland Nicolaus Copernicus University
Metsähovi Radio Observatory 14 metres Kirkkonummi, Finland Aalto University School of Science and Technology
Sheshan 25 metres 25 metres Sheshan, Shanghai, China Shanghai Astronomical Observatory
Nanshan 25 metres 25 metres Ürümqi, China
Observatorio Astronómico Nacional 40 metres and 14 metres Yebes, Guadalajara, Spain
Wettzell (20m Radio telescope) 20 metres Germany
Madrid Deep Space Communication Complex Robledo de Chavela, Spain INTA / NASA / JPL
Hartebeesthoek Radio Astronomy Observatory 26 metres Hartebeesthoek, South Africa National Research Foundation of South Africa
Arecibo Observatory 305 metres Arecibo, Puerto Rico SRI International / USRA / UMET

Additionally the EVN often links with the UK-based 7-element Jodrell Bank MERLIN interferometre. It can also be connected to the US Very Long Baseline Array (VLBA), achieving a global VLBI, obtaining sub-milliarcsecond resolution at frequencies higher than 5 GHz.[2]

e-EVN[edit]

Since 2004, the EVN has started to be linked together using international fibre optic networks, through a technique known as e-VLBI. The EXPReS project was designed to connect telescopes at Gigabit per second links via their National Research Networks and the Pan-European research network GÉANT2, and make the first astronomical experiments using this new technique. This allows researchers to take advantage of the e-EVN's Targets of Opportunity for conducting follow-on observations of transient events such as X-ray binary flares, supernova explosions and gamma-ray bursts.

EXPReS's objectives are to connect up to 16 of the world's most sensitive radio telescopes on six continents to the central data processor of the European VLBI Network at the Joint Institute for VLBI in Europe (JIVE). Specific activities involve securing "last-mile connections" and upgrading existing connections to the telescopes, updating the correlator to process up to 16 data streams at 1 Gbit/s each in real time and research possibilities for distributed computing to replace the centralized data processor.

External links[edit]

References[edit]

  1. ^ "Pictures of EVN telescopes". Retrieved 2014-02-03. 
  2. ^ "Introduction to the EVN". Retrieved 2014-02-03.