<?xml version="1.0"?>
<feed xmlns="http://www.w3.org/2005/Atom" xml:lang="en">
	<id>https://wiki.cern.ch/index.php?action=history&amp;feed=atom&amp;title=Low_Energy_Ion_Ring</id>
	<title>Low Energy Ion Ring - Revision history</title>
	<link rel="self" type="application/atom+xml" href="https://wiki.cern.ch/index.php?action=history&amp;feed=atom&amp;title=Low_Energy_Ion_Ring"/>
	<link rel="alternate" type="text/html" href="https://wiki.cern.ch/index.php?title=Low_Energy_Ion_Ring&amp;action=history"/>
	<updated>2026-05-24T21:33:40Z</updated>
	<subtitle>Revision history for this page on the wiki</subtitle>
	<generator>MediaWiki 1.44.0</generator>
	<entry>
		<id>https://wiki.cern.ch/index.php?title=Low_Energy_Ion_Ring&amp;diff=12401&amp;oldid=prev</id>
		<title>Vigen at 11:55, 24 April 2026</title>
		<link rel="alternate" type="text/html" href="https://wiki.cern.ch/index.php?title=Low_Energy_Ion_Ring&amp;diff=12401&amp;oldid=prev"/>
		<updated>2026-04-24T11:55:08Z</updated>

		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;col class=&quot;diff-marker&quot; /&gt;
				&lt;col class=&quot;diff-content&quot; /&gt;
				&lt;tr class=&quot;diff-title&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;2&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 11:55, 24 April 2026&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot; id=&quot;mw-diff-left-l1&quot;&gt;Line 1:&lt;/td&gt;
&lt;td colspan=&quot;2&quot; class=&quot;diff-lineno&quot;&gt;Line 1:&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;{{Short description|Particle accelerator at CERN}}&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The &#039;&#039;&#039;Low Energy Ion Ring&#039;&#039;&#039; (&#039;&#039;&#039;LEIR&#039;&#039;&#039;) is a particle accelerator at [[CERN]] used to accelerate ions from the [[&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Linac&lt;/ins&gt;#&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;Linac &lt;/ins&gt;3|LINAC 3]] to the [[Proton Synchrotron]] (PS) to provide &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;ions &lt;/ins&gt;for collisions within the [[Large Hadron Collider]] (LHC).&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;{{CERNaccelerators}}&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;{{Use dmy dates|date=September 2022}}&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt; &lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[File:Low Energy Ion Ring.jpg|thumb|The Low Energy Ion Ring  particle accelerator at CERN]]&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The &#039;&#039;&#039;Low Energy Ion Ring&#039;&#039;&#039; (&#039;&#039;&#039;LEIR&#039;&#039;&#039;) is a particle accelerator at [[CERN]] used to accelerate ions from the [[&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;CERN Hadron LINACs&lt;/del&gt;#&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;LINAC &lt;/del&gt;3|LINAC 3]] to the [[Proton Synchrotron]] (PS) to provide &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[ion]]s &lt;/del&gt;for collisions within the [[Large Hadron Collider]] (LHC).&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==History==&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==History==&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;LEIR was converted from a previous machine, the [[Low Energy Antiproton Ring]] (LEAR), a facility to decelerate and store &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[&lt;/del&gt;antiprotons&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;]]&lt;/del&gt;&amp;lt;ref&amp;gt;{{Cite web|url=http://public.web.cern.ch/public/en/research/Antimatter-en.html|title=The matter-antimatter asymmetry problem}}&amp;lt;/ref&amp;gt; and to deliver them to experiments; the last LEAR antiproton run took place in 1996. LEIR was first proposed in 1993&amp;lt;ref&amp;gt;{{Cite web | url=http://cdsweb.cern.ch/record/279362/files/ | title=A low energy accumulation ring of ions for LHC (a feasibility study) - CERN Document Server}}&amp;lt;/ref&amp;gt; but it wasn&#039;t until 2003 that work to transform the old experiment into the new accelerator was started. The upgrade took just over two years, being commissioned in October 2005&amp;lt;ref&amp;gt;{{Cite web | url=http://cerncourier.com/cws/article/cern/29480 | title=LEIR gets ions on course for the LHC – CERN Courier| date=25 November 2005}}&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;{{Cite book|url=http://accelconf.web.cern.ch/AccelConf/e06/PAPERS/WEOBPA02.PDF|title=LEIR commissioning in Proceedings of EPAC 2006, Edinburgh, Scotland|last=Belochitskii|display-authors=etal|first=P.|publisher=JACoW|year=2006|pages=1876–1878|access-date=14 October 2011|archive-date=8 November 2011|archive-url=https://web.archive.org/web/20111108221849/http://accelconf.web.cern.ch/accelconf/e06/PAPERS/WEOBPA02.PDF|url-status=dead}}&amp;lt;/ref&amp;gt; and tested for 4 months. In Autumn 2006 it was used to re-commission the PS to handle ions, and then again a year later it was used to re-commission the [[Super Proton Synchrotron|SPS]]. However, it wasn&#039;t until November 2010, five years later, that it successfully carried out its primary role to provide the lead ions to the LHC for its first ion collisions.&amp;lt;ref&amp;gt;[https://web.archive.org/web/20101110013909/http://www.telegraph.co.uk/science/large-hadron-collider/8116226/Large-Hadron-Collider-creates-mini-Big-Bang-with-lead-ions.html The Daily Telegraph]&amp;lt;/ref&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;LEIR was converted from a previous machine, the [[Low Energy Antiproton Ring]] (LEAR), a facility to decelerate and store antiprotons&amp;lt;ref&amp;gt;{{Cite web|url=http://public.web.cern.ch/public/en/research/Antimatter-en.html|title=The matter-antimatter asymmetry problem}}&amp;lt;/ref&amp;gt; and to deliver them to experiments; the last LEAR antiproton run took place in 1996. LEIR was first proposed in 1993&amp;lt;ref&amp;gt;{{Cite web | url=http://cdsweb.cern.ch/record/279362/files/ | title=A low energy accumulation ring of ions for LHC (a feasibility study) - CERN Document Server}}&amp;lt;/ref&amp;gt; but it wasn&#039;t until 2003 that work to transform the old experiment into the new accelerator was started. The upgrade took just over two years, being commissioned in October 2005&amp;lt;ref&amp;gt;{{Cite web | url=http://cerncourier.com/cws/article/cern/29480 | title=LEIR gets ions on course for the LHC – CERN Courier| date=25 November 2005}}&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;{{Cite book|url=http://accelconf.web.cern.ch/AccelConf/e06/PAPERS/WEOBPA02.PDF|title=LEIR commissioning in Proceedings of EPAC 2006, Edinburgh, Scotland|last=Belochitskii|display-authors=etal|first=P.|publisher=JACoW|year=2006|pages=1876–1878|access-date=14 October 2011|archive-date=8 November 2011|archive-url=https://web.archive.org/web/20111108221849/http://accelconf.web.cern.ch/accelconf/e06/PAPERS/WEOBPA02.PDF|url-status=dead}}&amp;lt;/ref&amp;gt; and tested for 4 months. In Autumn 2006 it was used to re-commission the PS to handle ions, and then again a year later it was used to re-commission the [[Super Proton Synchrotron|SPS]]. However, it wasn&#039;t until November 2010, five years later, that it successfully carried out its primary role to provide the lead ions to the LHC for its first ion collisions.&amp;lt;ref&amp;gt;[https://web.archive.org/web/20101110013909/http://www.telegraph.co.uk/science/large-hadron-collider/8116226/Large-Hadron-Collider-creates-mini-Big-Bang-with-lead-ions.html The Daily Telegraph]&amp;lt;/ref&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;During 2017, LEIR was running with &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[&lt;/del&gt;xenon&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;]] &lt;/del&gt;ions, sending them normally to SPS and, exceptionally to the LHC&amp;lt;ref&amp;gt;{{Cite web | url=https://home.cern/about/updates/2017/10/one-day-only-lhc-collides-xenon-beams | title=For one day only LHC collides xenon beams}}&amp;lt;/ref&amp;gt; for one day of physics. In 2018, the machine was running again with &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[&lt;/del&gt;lead&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;]] &lt;/del&gt;ions and had the objective to reach an LIU performance of more than {{val|9|e=10}} charges extracted. On 6 June 2018 that performance was achieved and also a new extraction record of {{val|10.35|e=10}} charges was accomplished.&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;During 2017, LEIR was running with xenon ions, sending them normally to SPS and, exceptionally to the LHC&amp;lt;ref&amp;gt;{{Cite web | url=https://home.cern/about/updates/2017/10/one-day-only-lhc-collides-xenon-beams | title=For one day only LHC collides xenon beams}}&amp;lt;/ref&amp;gt; for one day of physics. In 2018, the machine was running again with lead ions and had the objective to reach an LIU performance of more than {{val|9|e=10}} charges extracted. On 6 June 2018 that performance was achieved and also a new extraction record of {{val|10.35|e=10}} charges was accomplished.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Operation==&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==Operation==&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[File:LEIR_img_1001.jpg|thumb|Electron cooler (left) at LEIR. The electron source and dump are installed in the upper metallic cylinders.]]&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;LEIR takes long bunches of lead-208 ions from the LINAC 3, and splits them into 4 bunches. Each bunch contains {{val|2.2|e=8}} lead ions, which are accelerated from {{val|4.2|ul=MeV}} per nucleon to {{val|72|u=MeV}} per nucleon&amp;lt;ref&amp;gt;{{cite conference |title=The LHC Lead Injector Chain |url=http://accelconf.web.cern.ch/AccelConf/e04/PAPERS/TUPLT011.PDF |conference=Ninth European Particle Accelerator Conference (EPAC&#039;04) |author1=A. Beuret |display-authors=etal |location=Lucerne, Switzerland |conference-url=http://accelconf.web.cern.ch/accelconf/e04/ |date=July 2004}}&amp;lt;/ref&amp;gt; before passing them through to the PS for storage.&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;LEIR takes long bunches of &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[&lt;/del&gt;lead-208&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;]] &lt;/del&gt;ions from the LINAC 3, and splits them into 4 bunches. Each bunch contains {{val|2.2|e=8}} lead ions, which are accelerated from {{val|4.2|ul=MeV}} per &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[&lt;/del&gt;nucleon&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;]] &lt;/del&gt;to {{val|72|u=MeV}} per nucleon&amp;lt;ref&amp;gt;{{cite conference |title=The LHC Lead Injector Chain |url=http://accelconf.web.cern.ch/AccelConf/e04/PAPERS/TUPLT011.PDF |conference=Ninth European Particle Accelerator Conference (EPAC&#039;04) |author1=A. Beuret |display-authors=etal |location=Lucerne, Switzerland |conference-url=http://accelconf.web.cern.ch/accelconf/e04/ |date=July 2004}}&amp;lt;/ref&amp;gt; before passing them through to the PS for storage.&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The most important function of LEIR is not acceleration, but &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[&lt;/del&gt;electron cooling&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;]] &lt;/del&gt;to reduce the &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[Beam &lt;/del&gt;emittance&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;|emittance]] &lt;/del&gt;of the ion beam in order to maintain high &lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[Luminosity (scattering theory)|&lt;/del&gt;luminosity&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;]] &lt;/del&gt;of the final LHC beam. Each group of two bunches takes about 2.5 seconds to accelerate and cool, so with the LHC using 592 bunches of ions, it takes around 10 minutes for a complete fill of the LHC for operations.&amp;lt;ref&amp;gt;{{Cite journal |first=Michel |last=Chanel |title=LEIR: The Low Energy Ion Ring at CERN |journal=Nuclear Instruments and Methods in Physics Research A |volume=532 |issue=1–2 |pages=137–143 |url=http://chanel.home.cern.ch/chanel/design/leir.pub.final.pdf |url-status=dead |archive-url=https://web.archive.org/web/20120329111348/http://chanel.home.cern.ch/chanel/design/leir.pub.final.pdf |archive-date=2012-03-29 |id=CERN-AB-2003-086 |date=September 2003|bibcode=2004NIMPA.532..137C |doi=10.1016/j.nima.2004.06.040 }}&amp;lt;/ref&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;The most important function of LEIR is not acceleration, but electron cooling to reduce the emittance of the ion beam in order to maintain high luminosity of the final LHC beam. Each group of two bunches takes about 2.5 seconds to accelerate and cool, so with the LHC using 592 bunches of ions, it takes around 10 minutes for a complete fill of the LHC for operations.&amp;lt;ref&amp;gt;{{Cite journal |first=Michel |last=Chanel |title=LEIR: The Low Energy Ion Ring at CERN |journal=Nuclear Instruments and Methods in Physics Research A |volume=532 |issue=1–2 |pages=137–143 |url=http://chanel.home.cern.ch/chanel/design/leir.pub.final.pdf |url-status=dead |archive-url=https://web.archive.org/web/20120329111348/http://chanel.home.cern.ch/chanel/design/leir.pub.final.pdf |archive-date=2012-03-29 |id=CERN-AB-2003-086 |date=September 2003|bibcode=2004NIMPA.532..137C |doi=10.1016/j.nima.2004.06.040 }}&amp;lt;/ref&amp;gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-deleted&quot;&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;For more information, see [[wikipedia:Low Energy Ion Ring|Wikipedia]].&lt;/ins&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==References==&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;==References==&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{reflist}}&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{reflist}}&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;==External links==&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;*{{Commons category inline}}&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;{{Radiation}}&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{CERN}}&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{CERN}}&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;br&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{DEFAULTSORT:Low Energy Ion Ring}}&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot;&gt;&lt;/td&gt;&lt;td style=&quot;background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;{{DEFAULTSORT:Low Energy Ion Ring}}&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;[[Category:CERN accelerators&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;]]&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;+&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;[[Category:CERN &lt;ins style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;particle &lt;/ins&gt;accelerators]]&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[Category:Particle accelerators]]&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[Category:CERN facilities]]&lt;/del&gt;&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td class=&quot;diff-marker&quot; data-marker=&quot;−&quot;&gt;&lt;/td&gt;&lt;td style=&quot;color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;&quot;&gt;&lt;div&gt;&lt;del style=&quot;font-weight: bold; text-decoration: none;&quot;&gt;[[Category:Particle physics facilities&lt;/del&gt;]]&lt;/div&gt;&lt;/td&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-side-added&quot;&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;</summary>
		<author><name>Vigen</name></author>
	</entry>
	<entry>
		<id>https://wiki.cern.ch/index.php?title=Low_Energy_Ion_Ring&amp;diff=12368&amp;oldid=prev</id>
		<title>Vigen: 1 revision imported from :wikipedia:Low_Energy_Ion_Ring</title>
		<link rel="alternate" type="text/html" href="https://wiki.cern.ch/index.php?title=Low_Energy_Ion_Ring&amp;diff=12368&amp;oldid=prev"/>
		<updated>2026-04-24T11:50:53Z</updated>

		<summary type="html">&lt;p&gt;1 revision imported from &lt;a href=&quot;https://en.wikipedia.org/wiki/Low_Energy_Ion_Ring&quot; class=&quot;extiw&quot; title=&quot;wikipedia:Low Energy Ion Ring&quot;&gt;wikipedia:Low_Energy_Ion_Ring&lt;/a&gt;&lt;/p&gt;
&lt;table style=&quot;background-color: #fff; color: #202122;&quot; data-mw=&quot;interface&quot;&gt;
				&lt;tr class=&quot;diff-title&quot; lang=&quot;en&quot;&gt;
				&lt;td colspan=&quot;1&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;← Older revision&lt;/td&gt;
				&lt;td colspan=&quot;1&quot; style=&quot;background-color: #fff; color: #202122; text-align: center;&quot;&gt;Revision as of 11:50, 24 April 2026&lt;/td&gt;
				&lt;/tr&gt;&lt;tr&gt;&lt;td colspan=&quot;2&quot; class=&quot;diff-notice&quot; lang=&quot;en&quot;&gt;&lt;div class=&quot;mw-diff-empty&quot;&gt;(No difference)&lt;/div&gt;
&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;</summary>
		<author><name>Vigen</name></author>
	</entry>
	<entry>
		<id>https://wiki.cern.ch/index.php?title=Low_Energy_Ion_Ring&amp;diff=12367&amp;oldid=prev</id>
		<title>wikipedia&gt;Bibliophilen: Does not belong in category &quot;CERN&quot;—it is already in the sub-category &quot;CERN accelerators&quot;.</title>
		<link rel="alternate" type="text/html" href="https://wiki.cern.ch/index.php?title=Low_Energy_Ion_Ring&amp;diff=12367&amp;oldid=prev"/>
		<updated>2025-05-30T08:51:06Z</updated>

		<summary type="html">&lt;p&gt;Does not belong in category &amp;quot;CERN&amp;quot;—it is already in the sub-category &amp;quot;CERN accelerators&amp;quot;.&lt;/p&gt;
&lt;p&gt;&lt;b&gt;New page&lt;/b&gt;&lt;/p&gt;&lt;div&gt;{{Short description|Particle accelerator at CERN}}&lt;br /&gt;
{{CERNaccelerators}}&lt;br /&gt;
{{Use dmy dates|date=September 2022}}&lt;br /&gt;
&lt;br /&gt;
[[File:Low Energy Ion Ring.jpg|thumb|The Low Energy Ion Ring  particle accelerator at CERN]]&lt;br /&gt;
The &amp;#039;&amp;#039;&amp;#039;Low Energy Ion Ring&amp;#039;&amp;#039;&amp;#039; (&amp;#039;&amp;#039;&amp;#039;LEIR&amp;#039;&amp;#039;&amp;#039;) is a particle accelerator at [[CERN]] used to accelerate ions from the [[CERN Hadron LINACs#LINAC 3|LINAC 3]] to the [[Proton Synchrotron]] (PS) to provide [[ion]]s for collisions within the [[Large Hadron Collider]] (LHC).&lt;br /&gt;
&lt;br /&gt;
==History==&lt;br /&gt;
LEIR was converted from a previous machine, the [[Low Energy Antiproton Ring]] (LEAR), a facility to decelerate and store [[antiprotons]]&amp;lt;ref&amp;gt;{{Cite web|url=http://public.web.cern.ch/public/en/research/Antimatter-en.html|title=The matter-antimatter asymmetry problem}}&amp;lt;/ref&amp;gt; and to deliver them to experiments; the last LEAR antiproton run took place in 1996. LEIR was first proposed in 1993&amp;lt;ref&amp;gt;{{Cite web | url=http://cdsweb.cern.ch/record/279362/files/ | title=A low energy accumulation ring of ions for LHC (a feasibility study) - CERN Document Server}}&amp;lt;/ref&amp;gt; but it wasn&amp;#039;t until 2003 that work to transform the old experiment into the new accelerator was started. The upgrade took just over two years, being commissioned in October 2005&amp;lt;ref&amp;gt;{{Cite web | url=http://cerncourier.com/cws/article/cern/29480 | title=LEIR gets ions on course for the LHC – CERN Courier| date=25 November 2005}}&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;{{Cite book|url=http://accelconf.web.cern.ch/AccelConf/e06/PAPERS/WEOBPA02.PDF|title=LEIR commissioning in Proceedings of EPAC 2006, Edinburgh, Scotland|last=Belochitskii|display-authors=etal|first=P.|publisher=JACoW|year=2006|pages=1876–1878|access-date=14 October 2011|archive-date=8 November 2011|archive-url=https://web.archive.org/web/20111108221849/http://accelconf.web.cern.ch/accelconf/e06/PAPERS/WEOBPA02.PDF|url-status=dead}}&amp;lt;/ref&amp;gt; and tested for 4 months. In Autumn 2006 it was used to re-commission the PS to handle ions, and then again a year later it was used to re-commission the [[Super Proton Synchrotron|SPS]]. However, it wasn&amp;#039;t until November 2010, five years later, that it successfully carried out its primary role to provide the lead ions to the LHC for its first ion collisions.&amp;lt;ref&amp;gt;[https://web.archive.org/web/20101110013909/http://www.telegraph.co.uk/science/large-hadron-collider/8116226/Large-Hadron-Collider-creates-mini-Big-Bang-with-lead-ions.html The Daily Telegraph]&amp;lt;/ref&amp;gt;&lt;br /&gt;
&lt;br /&gt;
During 2017, LEIR was running with [[xenon]] ions, sending them normally to SPS and, exceptionally to the LHC&amp;lt;ref&amp;gt;{{Cite web | url=https://home.cern/about/updates/2017/10/one-day-only-lhc-collides-xenon-beams | title=For one day only LHC collides xenon beams}}&amp;lt;/ref&amp;gt; for one day of physics. In 2018, the machine was running again with [[lead]] ions and had the objective to reach an LIU performance of more than {{val|9|e=10}} charges extracted. On 6 June 2018 that performance was achieved and also a new extraction record of {{val|10.35|e=10}} charges was accomplished.&lt;br /&gt;
&lt;br /&gt;
==Operation==&lt;br /&gt;
[[File:LEIR_img_1001.jpg|thumb|Electron cooler (left) at LEIR. The electron source and dump are installed in the upper metallic cylinders.]]&lt;br /&gt;
LEIR takes long bunches of [[lead-208]] ions from the LINAC 3, and splits them into 4 bunches. Each bunch contains {{val|2.2|e=8}} lead ions, which are accelerated from {{val|4.2|ul=MeV}} per [[nucleon]] to {{val|72|u=MeV}} per nucleon&amp;lt;ref&amp;gt;{{cite conference |title=The LHC Lead Injector Chain |url=http://accelconf.web.cern.ch/AccelConf/e04/PAPERS/TUPLT011.PDF |conference=Ninth European Particle Accelerator Conference (EPAC&amp;#039;04) |author1=A. Beuret |display-authors=etal |location=Lucerne, Switzerland |conference-url=http://accelconf.web.cern.ch/accelconf/e04/ |date=July 2004}}&amp;lt;/ref&amp;gt; before passing them through to the PS for storage.&lt;br /&gt;
&lt;br /&gt;
The most important function of LEIR is not acceleration, but [[electron cooling]] to reduce the [[Beam emittance|emittance]] of the ion beam in order to maintain high [[Luminosity (scattering theory)|luminosity]] of the final LHC beam. Each group of two bunches takes about 2.5 seconds to accelerate and cool, so with the LHC using 592 bunches of ions, it takes around 10 minutes for a complete fill of the LHC for operations.&amp;lt;ref&amp;gt;{{Cite journal |first=Michel |last=Chanel |title=LEIR: The Low Energy Ion Ring at CERN |journal=Nuclear Instruments and Methods in Physics Research A |volume=532 |issue=1–2 |pages=137–143 |url=http://chanel.home.cern.ch/chanel/design/leir.pub.final.pdf |url-status=dead |archive-url=https://web.archive.org/web/20120329111348/http://chanel.home.cern.ch/chanel/design/leir.pub.final.pdf |archive-date=2012-03-29 |id=CERN-AB-2003-086 |date=September 2003|bibcode=2004NIMPA.532..137C |doi=10.1016/j.nima.2004.06.040 }}&amp;lt;/ref&amp;gt;&lt;br /&gt;
&lt;br /&gt;
==References==&lt;br /&gt;
{{reflist}}&lt;br /&gt;
==External links==&lt;br /&gt;
*{{Commons category inline}}&lt;br /&gt;
&lt;br /&gt;
{{Radiation}}&lt;br /&gt;
{{CERN}}&lt;br /&gt;
&lt;br /&gt;
{{DEFAULTSORT:Low Energy Ion Ring}}&lt;br /&gt;
[[Category:CERN accelerators]]&lt;br /&gt;
[[Category:Particle accelerators]]&lt;br /&gt;
[[Category:CERN facilities]]&lt;br /&gt;
[[Category:Particle physics facilities]]&lt;/div&gt;</summary>
		<author><name>wikipedia&gt;Bibliophilen</name></author>
	</entry>
</feed>