Korean VLBI Network

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Korean VLBI Network
Yonsei radio observatory.jpg
The telescope in Yonsei
Location(s)
Coordinates 37°33′44″N126°56′35″E / 37.5622°N 126.9431°E / 37.5622; 126.9431 Coordinates: 37°33′44″N126°56′35″E / 37.5622°N 126.9431°E / 37.5622; 126.9431 OOjs UI icon edit-ltr-progressive.svg
Organization Korea Astronomy and Space Science Institute   OOjs UI icon edit-ltr-progressive.svg
Wavelength 2 mm (150 GHz)–14 mm (21 GHz)
Built2001–2008 (2001–2008) OOjs UI icon edit-ltr-progressive.svg
Telescope styleradio interferometer  OOjs UI icon edit-ltr-progressive.svg
Number of telescopes3  OOjs UI icon edit-ltr-progressive.svg
Diameter21 m (68 ft 11 in) OOjs UI icon edit-ltr-progressive.svg
Angular resolution 5 milliarcsecond, 1 milliarcsecond  OOjs UI icon edit-ltr-progressive.svg
Website radio.kasi.re.kr/kvn/main_kvn.php OOjs UI icon edit-ltr-progressive.svg
South Korea physical map.svg
Red pog.svg
Location of Korean VLBI Network
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The Korean VLBI Network (KVN) is a radio astronomy observatory located in South Korea. It comprises three 21-meter radio telescopes that function as an interferometer, using the technique of very-long-baseline interferometry (VLBI).

Contents

Characteristics

The KVN has three main dishes, each of 21m diameter and at respective separations of 300–500 km. All three dishes are located on university campus. Two are on the Korean peninsula: Yonsei University (KY) and Ulsan University (KU), and the third is located on Jeju Island on the campus of Jeju International University (formerly Tamna University; KT). The KVN antennas are Cassegrain-types with alt-az mounts. Each telescope has a 21-m diameter main reflector with a focal length of 6.78 m. The main reflectors consist of 200 aluminum panels each with a manufacturing surface accuracy of 65 microns. [1]

A fourth telescope, the existing 14m dish located at the Taeduk Radio Astronomy Observatory, will be linked to the KVN in the future via optical fiber networks. [2]

KVN focuses on millimeter-wavelength VLBI, and is designed to make simultaneous measurements at four different observing frequencies: 22, 43, 86, and 129 GHz. The telescopes can operate together with VLBI networks in Japan and China the East Asian VLBI Network (EAVN). The EAVN consists of 19 antennae with a maximum baseline of 5000 km operating at 22 GHz; it can also operate at 43 GHz using only 9 antennae. The first fringes for EAVN at 22 GHz were successfully detected in 2009. [3]

The KVN has also successfully been used for real-time VLBI between Korea and Europe. [4]

Key science

KVN studies the formation and death processes of stars, the structure and dynamics of the Milky Way, the nature of active galactic nuclei, and other astronomical topics. KVN is also used for geodesy in detecting tectonic movements in the Korean peninsula.

Visiting

The visitor's center for KVN is located at the Advanced Science & Technology Center on the campus of Yonsei University in Seoul.

See also

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References

  1. Lee, Sang-Sung (2011). "Single dish performance of KVN 21-m radio telescopes: Simultaneous observations at 22 and 43 GHz". Publications of the Astronomical Society of the Pacific. 123 (910): 1398–1411. arXiv: 1110.3881 . Bibcode:2011PASP..123.1398L. doi:10.1086/663326. S2CID   118610325.
  2. "::: KVN :::". Archived from the original on 2016-03-04. Retrieved 2015-11-11.
  3. http://kvn.kasi.re.kr/index.html/ . Retrieved 2015-11-11.{{cite web}}: Missing or empty |title= (help)
  4. http://www.kasi.re.kr/View.aspx?id=report&page=2&si=False&sn=False&ss=True&sc=False&keyword=&pagesize=20&uid=3645 [ dead link ]