Editing Westerbork Synthesis Radio Telescope

{{Short description|Aperture synthesis interferometer in the Netherlands}}
{{Infobox telescope}}
[[File:WesterborkSynthesisRadioTelescope.JPG|upright=1.35|thumb|WSRT in operation in 2006]]
[[File:Westerbork antenna portrait.jpg|thumb|upright|Single antenna in 2006]]

The '''Westerbork Synthesis Radio Telescope''' ('''WSRT''') is an [[aperture synthesis]] [[interferometer]] built on the site of the former World War II Nazi detention and transit [[Westerbork transit camp|camp Westerbork]], north of the village of [[Westerbork (village)|Westerbork]], [[Midden-Drenthe]], in the northeastern [[Netherlands]].

==Overview==
The WSRT comprises fourteen {{convert|25|m|ft|abbr=on}} radio telescopes deployed in a linear array arranged on a {{convert|2.7|km|abbr=on}} East-West line, of which 10 are in a fixed equidistant position, 2 are nearby on a {{convert|300|m|ft|abbr=on}} rail track, and 2 are located {{convert|1|km|mi|abbr=on}} eastwards on another {{convert|200|m|ft|abbr=on}} rail track. It has a similar arrangement to other [[radio telescope]]s such as the [[One-Mile Telescope]], [[Australia Telescope Compact Array]] and the [[Ryle Telescope]]. Its [[Equatorial mount]] is what sets it apart from most other radio telescopes, most of which have an [[Altazimuth mount]]. This makes it specifically useful for specific types of science, like polarized emission research as the detectors maintain a constant orientation on the sky during an observation. Ten of the telescopes are on fixed mountings while the remaining two dishes are movable along two [[rail tracks]]. The telescope was completed in 1970 and underwent a major upgrade between 1995{{snd}}2000.<ref name="WRST_History">{{cite web |url=https://old.astron.nl/radio-observatory/public/history-wsrt/history-wsrt |title=History of the WRST {{pipe}} ASTRON |website=astron.nl |publisher=[[ASTRON]] |language=en |access-date=2020-12-07 |url-status=usurped |archive-url=https://web.archive.org/web/20190412102415/https://old.astron.nl/radio-observatory/public/history-wsrt/history-wsrt |archive-date=2019-04-12 | df= dmy-all}}</ref>

The telescopes in the array can operate at several frequencies between {{frequency|120|[[MHz]]}} and {{frequency|8.3|[[GHz]]}} with an instantaneous bandwidth of {{frequency|120|MHz}} and 8092{{hyphen}}line spectral resolution.<ref name="WRST_Guide">{{cite web |url=http://www.astron.nl/radio-observatory/astronomers/wsrt-guide-observations/wsrt-guide-observations |title=WSRT GUIDE TO OBSERVATIONS |website=astron.nl |publisher=[[ASTRON]] |language=en |access-date=2020-12-07 |url-status=dead |archive-url=https://web.archive.org/web/20150103112814/http://astron.nl/radio-observatory/astronomers/wsrt-guide-observations/wsrt-guide-observations |archive-date=2015-01-03 | df= dmy-all}}</ref> The WSRT is often combined with other telescopes around the world to perform [[very-long-baseline interferometry]] (VLBI) observations, being part of the [[European VLBI Network]].<ref>[http://www.evlbi.org/intro/intro.html Introduction to the EVN] {{Webarchive|url=https://web.archive.org/web/20120224193835/http://www.evlbi.org/intro/intro.html |date=2012-02-24 }}, [[European VLBI Network]].</ref> The telescope is operated by [[ASTRON]], the Netherlands Institute for Radio Astronomy.

WSRT performed a major upgrade in 2013 as part of the APERTIF (APERture Tile In Focus) project, where the current detectors were replaced with [[Focal-plane array (radio astronomy)|focal-plane arrays]].<ref>[http://www.astron.nl/general/apertif/apertif What is Apertif?] {{Webarchive|url=https://web.archive.org/web/20150116021707/http://www.astron.nl/general/apertif/apertif |date=2015-01-16 }}, [[ASTRON]].</ref> The Telescope was out of operation for the upgrade from 2015 to 2019, which allows a 25x larger field of view. The upgraded telescope is used for large scale surveys of the northern sky, bringing back focus on the [[Hydrogen line]] for which it was originally designed, but also large [[pulsar]] searches and other science.<ref>[https://arxiv.org/abs/2109.14234 Apertif, Phased Array Feeds for the Westerbork Synthesis Radio Telescope.</ref>

The WSRT is also an International [[GNSS]] Service site.<ref>[https://web.archive.org/web/19991007200915/http://igscb.jpl.nasa.gov/network/site/wsrt.html IGS Station: wsrt], International GNSS Service.</ref>

WSRT observed galaxies in the [[Spitzer Infrared Nearby Galaxies Survey]] at wavelengths of {{convert|18 and 22|cm|in|abbr=on}}.<ref>{{cite journal | bibcode=2007A&A...461..455B | title=The Westerbork SINGS survey. I. Overview and image atlas | journal=Astronomy and Astrophysics | volume=461 | issue=2 | page=455|arxiv = astro-ph/0610114 |doi = 10.1051/0004-6361:20066092 | year=2007 | last1=Braun | first1=R. | last2=Oosterloo | first2=T. A. | last3=Morganti | first3=R.|author3-link=Raffaella Morganti | last4=Klein | first4=U. | last5=Beck | first5=R. | s2cid=9798900 }}</ref>

The WSRT site is also hosting one of the two experimental [[EMBRACE (telescope)|EMBRACE]] (Electronic MultiBeam Radio Astronomy ConcEpt) [[phased array]] telescopes, part of the Phase 2 of the [[Square Kilometre Array]] (SKA) project.<ref>{{cite web| url=http://www.astron.nl/r-d-laboratory/ska/embrace/embrace| title=EMBRACE| publisher=ASTRON| access-date=2015-05-17}}</ref>

==References==
{{Reflist|30em|refs=

}}

==External links==
*{{Commons category-inline}}

{{Radio-astronomy}}

[[Category:Astronomical observatories in the Netherlands]]
[[Category:Buildings and structures in Drenthe]]
[[Category:Interferometric telescopes]]
[[Category:Midden-Drenthe]]
[[Category:Radio telescopes]]