HOME

TheInfoList



OR:

The European VLBI Network (EVN) is a network of radio telescopes located primarily in Europe and Asia, with additional antennas in South Africa and Puerto Rico, which performs very high angular resolution observations of cosmic radio sources using
very-long-baseline interferometry Very-long-baseline interferometry (VLBI) is a type of astronomical interferometry used in radio astronomy. In VLBI a signal from an astronomical radio source, such as a quasar, is collected at multiple radio telescopes on Earth or in space. T ...
(VLBI). The EVN is the most sensitive VLBI array in the world, and the only one capable of real-time observations. The Joint Institute for VLBI ERIC (JIVE) acts as the central organisation in the EVN, providing both scientific user support and a correlator facility. Very Long Baseline Interferometry (VLBI) achieves ultra-high angular resolution and is a multi-disciplinary technique used in astronomy, geodesy and astrometry. The EVN operates an open-sky policy, allowing anyone to propose an observation using the network


EVN Telescopes

The EVN network comprises 22 telescope facilities: Additionally the EVN often links with the UK-based 7-element
Jodrell Bank Jodrell Bank Observatory ( ) in Cheshire, England hosts a number of radio telescopes as part of the Jodrell Bank Centre for Astrophysics at the University of Manchester. The observatory was established in 1945 by Bernard Lovell, a radio astron ...
MERLIN The Multi-Element Radio Linked Interferometer Network (MERLIN) is an interferometer array of radio telescopes spread across England. The array is run from Jodrell Bank Observatory in Cheshire by the University of Manchester on behalf of UK Re ...
interferometer. 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.


e-EVN

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 GÉANT (''Gigabit European Academic Network'') is the pan-European data Computer network, network for the research and education community. It interconnects national research and education networks (NRENs) across Europe, enabling collaboration ...
, 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 A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last stellar evolution, evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion ...
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 ERIC (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.


History

The EVN was formed in 1980 by a consortium of five of the major radio astronomy institutes in
Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...
(the European Consortium for VLBI). Since 1980, the EVN and the Consortium has grown to include many institutes with numerous
radio telescopes A radio telescope is a specialized antenna (radio), antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the r ...
in several western European countries as well as associated institutes with telescopes in Russia, Ukraine, China and South Africa. Proposals for an additional telescope in Spain are under consideration. Observations using the EVN have contributed to scientific research on Fast Radio Bursts (FRBs), gravitational lensing, and supermassive black holes.


See also

* Northern Extended Millimeter Array


References


External links

*
The European VLBI Network
on the internet
Joint Institute for VLBI ERIC
on the internet {{Authority control Astronomy in Europe Interferometric telescopes Radio telescopes