Mitigating Collimation Impedance and Improving Halo Cleaning with New Optics and Settings Strategy of the HL-LHC Betatron Collimation System

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Lindström, Bjorn; Bruce, Roderik; Buffat, Xavier; De Maria, Riccardo; Giacomel, Lorenzo; Hermes, Pascal; Mirarchi, Daniele; Mounet, Nicolas; Persson, Tobias; Redaelli, Stefano; Tomás García, Rogelio; Van der Veken, Frederik; Wegscheider, Andreas" /> <meta name="keywords" content="optics, impedance, collimation, simulation, experiment" /> <script type="text/javascript" src="http://cds.cern.ch/js/jquery.min.js"></script>  <link rel="stylesheet" href="http://cds.cern.ch/img/webnews.css" type="text/css" />  <script type="text/javascript" src="http://cds.cern.ch/js/webnews.js?v=20131009"></script> <meta property="fb:app_id" content="137353533001720"/> <script type="text/x-mathjax-config"> MathJax.Hub.Config({ tex2jax: {inlineMath: [['$','$']], processEscapes: true}, showProcessingMessages: false, messageStyle: "none" }); </script> <script src="/MathJax/MathJax.js?config=TeX-AMS_CHTML" type="text/javascript"> </script>  <meta content="JACOW : Mitigating Collimation Impedance and Improving Halo Cleaning with New Optics and Settings Strategy of the HL-LHC Betatron Collimation System" name="citation_title" /> <meta content="Lindström, Bjorn" name="citation_author" /> <meta content="Wegscheider, Andreas" name="citation_author" /> <meta content="Redaelli, Stefano" name="citation_author" /> <meta content="Tomás García, Rogelio" name="citation_author" /> <meta content="Mirarchi, Daniele" name="citation_author" /> <meta content="Bruce, Roderik" name="citation_author" /> <meta content="Buffat, Xavier" name="citation_author" /> <meta content="De Maria, Riccardo" name="citation_author" /> <meta content="Giacomel, Lorenzo" name="citation_author" /> <meta content="Hermes, Pascal" name="citation_author" /> <meta content="Van der Veken, Frederik" name="citation_author" /> <meta content="Mounet, Nicolas" name="citation_author" /> <meta content="Persson, Tobias" name="citation_author" /> <meta content="10.18429/JACoW-HB2023-TUC4C2" name="citation_doi" /> <meta content="JACoW HB" name="citation_journal_title" /> <meta content="2023" name="citation_volume" /> <meta content="183-187" name="citation_firstpage" /> <meta content="2024" name="citation_publication_date" /> <meta name="citation_online_date" content="2024/06/15"> <meta content="10.18429/JACoW-HB2023-TUC4C2" name="citation_doi" /> <meta name="citation_pdf_url" content="http://cds.cern.ch/record/2900905/files/document.pdf" />  <meta content="JACOW" property="og:title" /> <meta content="Mitigating Collimation Impedance and Improving Halo Cleaning with New Optics and Settings Strategy of the HL-LHC Betatron Collimation System" property="og:title" /> <meta content="website" property="og:type" /> <meta content="website" property="og:type" /> <meta content="http://cds.cern.ch/record/2900905" property="og:url" /> <meta content="CERN Document Server" property="og:site_name" /> <meta content="JACOW" property="og:description" /> <meta content="With High Luminosity Large Hadron Collider (HL-LHC) beam intensities, there are concerns that the beam losses in the dispersion suppressors around the betatron cleaning insertion might exceed the quench limits. 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var affiliation = $(this).data('affiliation') + '</br>'; var contribution = $(this).data('contribution') + '</br>'; $.magnificPopup.open({ items: { src: '<div id="ovelary-mathjax" class="overlay-white oc-content overlay-white-500">' + author + affiliation + contribution + '</div>', type: 'inline' }, callbacks: { open: function() { var div = document.getElementById("overlay-mathjax") MathJax.Hub.Queue(["Typeset", MathJax.Hub, div]); }, } }) }) }); </script> <tr><td class="formatRecordLabel"> Title </td><td style="padding-left:5px;"><b>Mitigating Collimation Impedance and Improving Halo Cleaning with New Optics and Settings Strategy of the HL-LHC Betatron Collimation System</b></td></tr> <tr><td class="formatRecordLabel"><span style="white-space:nowrap;"> Author(s) </span> </td><td style="padding-left:5px;"> <script type="text/javascript"> function toggle_authors_visibility(){ var more = document.getElementById('more'); var link = document.getElementById('link'); var extension = document.getElementById('extension'); if (more.style.display=='none'){ more.style.display = ''; extension.style.display = 'none'; link.innerHTML = "Hide" } else { more.style.display = 'none'; extension.style.display = ''; link.innerHTML = "Show all 13 authors" } link.style.color = "rgb(204,0,0);" } function set_up(){ var extension = document.getElementById('extension'); extension.innerHTML = ""; toggle_authors_visibility(); } </script> <a name="show_hide" /><a href="http://cds.cern.ch/search?f=author&p=Lindstr%C3%B6m%2C%20Bjorn&ln=en">Lindström, Bjorn</a> (CERN) ; <a href="http://cds.cern.ch/search?f=author&p=Bruce%2C%20Roderik&ln=en">Bruce, Roderik</a> (CERN) ; <a href="http://cds.cern.ch/search?f=author&p=Buffat%2C%20Xavier&ln=en">Buffat, Xavier</a> (CERN) ; <a href="http://cds.cern.ch/search?f=author&p=De%20Maria%2C%20Riccardo&ln=en">De Maria, Riccardo</a> (CERN) ; <a href="http://cds.cern.ch/search?f=author&p=Giacomel%2C%20Lorenzo&ln=en">Giacomel, Lorenzo</a> (CERN) ; <a href="http://cds.cern.ch/search?f=author&p=Hermes%2C%20Pascal&ln=en">Hermes, Pascal</a> (CERN) ; <a href="http://cds.cern.ch/search?f=author&p=Mirarchi%2C%20Daniele&ln=en">Mirarchi, Daniele</a> (CERN) ; <a href="http://cds.cern.ch/search?f=author&p=Mounet%2C%20Nicolas&ln=en">Mounet, Nicolas</a> (CERN) ; <a href="http://cds.cern.ch/search?f=author&p=Persson%2C%20Tobias&ln=en">Persson, Tobias</a> (CERN) ; <a href="http://cds.cern.ch/search?f=author&p=Redaelli%2C%20Stefano&ln=en">Redaelli, Stefano</a> (CERN)<span id="more" style=""> ; <a href="http://cds.cern.ch/search?f=author&p=Tom%C3%A1s%20Garc%C3%ADa%2C%20Rogelio&ln=en">Tomás García, Rogelio</a> (CERN) ; <a href="http://cds.cern.ch/search?f=author&p=Van%20der%20Veken%2C%20Frederik&ln=en">Van der Veken, Frederik</a> (CERN) ; <a href="http://cds.cern.ch/search?f=author&p=Wegscheider%2C%20Andreas&ln=en">Wegscheider, Andreas</a> (CERN)</span> <span id="extension"></span> <small><i><a id="link" href="#" onclick="toggle_authors_visibility()" style="color:rgb(204,0,0);"></a></i></small><script type="text/javascript">set_up()</script></td></tr> <tr><td class="formatRecordLabel"> Publication </td><td style="padding-left:5px;">2024</td></tr> <tr><td class="formatRecordLabel"> Number of pages </td><td style="padding-left:5px;">5</td></tr> <tr><td class="formatRecordLabel"> In: </td><td style="padding-left:5px;"><a href="http://dx.doi.org/10.18429/JACoW-HB2023-TUC4C2"><i>JACoW HB</i> 2023 (2024) 183-187</a> </a></td></tr> <tr><td class="formatRecordLabel"> In: </td><td style="padding-left:5px;"><a href="http://cds.cern.ch/record/2895374">68th ICFA Advanced Beam Dynamics workshop on high-Intensity and High-Brightness Hadron Beams (HB 2023)</a>, CERN, Geneva, Switzerland, 9 - 13 Oct 2023, pp.183-187</td></tr> <tr><td class="formatRecordLabel"> DOI </td><td style="padding-left:5px;"><a href="http://dx.doi.org/10.18429/JACoW-HB2023-TUC4C2" title="DOI" target="_blank">10.18429/JACoW-HB2023-TUC4C2</a> <tr><td class="formatRecordLabel"> Subject category </td><td style="padding-left:5px;">Accelerators and Storage Rings</td></tr> <tr><td class="formatRecordLabel"> Abstract </td><td style="padding-left:5px;">With High Luminosity Large Hadron Collider (HL-LHC) beam intensities, there are concerns that the beam losses in the dispersion suppressors around the betatron cleaning insertion might exceed the quench limits. Furthermore, to maximize the beam lifetime it is important to reduce the impedance as much as possible. The collimators constitute one of the main sources of impedance in HL-LHC, given the need to operate with small collimator gaps. To improve this, a new optics was developed which increases the beta function in the collimation area, as well as the single pass dispersion from the primary collimators to the downstream shower absorbers. Other possible improvements from orbit bumps, to further enhance the locally generated dispersion, and from asymmetric collimator settings were also studied. The new solutions were partially tested with 6.8 TeV beams at the LHC in a dedicated machine experiment in 2022. In this paper, the new performance is reviewed and prospects for future operational deployment are discussed.</td></tr> <tr><td class="formatRecordLabel"> Copyright/License </td><td style="padding-left:5px;">© 2024-2025 the author(s) (License: <a href="https://creativecommons.org/licenses/by/3.0">CC-BY-3.0</a>)</td></tr> </table> <br/>Corresponding record in: <a href="http://inspirehep.net/record/2775996">Inspire</a> <small> </small> <br/> <br/><br/><div align="right"><div style="padding-bottom:2px;padding-top:30px;"><span class="moreinfo" style="margin-right:10px;"> <a href="" class="moreinfo">Back to search</a> </span></div></div> <div class="bottom-left-folded"><div class="recordlastmodifiedbox" style="position:relative;margin-left:1px"> Record created 2024-06-15, last modified 2024-06-15</div></div> <div class="bottom-right-folded" style="text-align:right;padding-bottom:2px;"> <span class="moreinfo" style="margin-right:10px;"><a href="/search?ln=en&p=recid%3A2900905&rm=wrd" class="moreinfo">Similar records</a></span></div> </div> </div> </div> <br/> <br /> <div class="detailedrecordminipanel"> <div class="top-left"></div><div class="top-right"></div> <div class="inside"> <div id="detailedrecordminipanelfile" style="width:33%;float:left;text-align:center;margin-top:0"> <div><small class="detailedRecordActions">Fulltext:</small> <br /><a href="/record/2900905/files/document.pdf"><img style="border:none" src="/img/file-icon-text-34x48.gif" alt="Download fulltext" /><br />PDF</a><br /></div> </div> <div id="detailedrecordminipanelreview" style="width:30%;float:left;text-align:center"> </div> <div id="detailedrecordminipanelactions" style="width:36%;float:right;text-align:right;"> <ul class="detailedrecordactions"> <li><a href="/yourbaskets/add?ln=en&recid=2900905">Add to personal basket</a></li> <li>Export as <a style="text-decoration:underline;font-weight:normal" href="/record/2900905/export/hx?ln=en">BibTeX</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2900905/export/hm?ln=en">MARC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2900905/export/xm?ln=en">MARCXML</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2900905/export/xd?ln=en">DC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2900905/export/xe?ln=en">EndNote</a>,  <a style="text-decoration:underline;font-weight:normal" href="/record/2900905/export/xn?ln=en">NLM</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2900905/export/xw?ln=en">RefWorks</a> </li> </ul> <div style='padding-left: 13px;'>  <div id="bookmark"></div> <div id="bookmark_sciencewise"></div> <style type="text/css"> #bookmark_sciencewise, #bookmark {float: left;} #bookmark_sciencewise li {padding: 2px; width: 25px;} #bookmark_sciencewise ul, #bookmark ul {list-style-image: none;} </style> <script type="text/javascript" src="/js/jquery.bookmark.min.js"></script> <style type="text/css">@import "/css/jquery.bookmark.css";</style> <script type="text/javascript">// <![CDATA[ $.bookmark.addSite('sciencewise', 'ScienceWise.info', 'http://cds.cern.ch/img/sciencewise.png', 'en', 'bookmark', 'http://sciencewise.info/bookmarks/cds:2900905/add'); $('#bookmark_sciencewise').bookmark({sites: ['sciencewise']}); $('#bookmark').bookmark({ sites: ['facebook', 'twitter', 'linkedin', 'google_plusone'], icons: '/img/bookmarks.png', url: 'http://cds.cern.ch/record/2900905', addEmail: true, title: "Mitigating Collimation Impedance and Improving Halo Cleaning with New Optics and Settings Strategy of the HL-LHC Betatron Collimation System", description: "With High Luminosity Large Hadron Collider (HL-LHC) beam intensities, there are concerns that the beam losses in the dispersion suppressors around the betatron cleaning insertion might exceed the quench limits. 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Mitigating Collimation Impedance and Improving Halo Cleaning with New Optics and Settings Strategy of the HL-LHC Betatron Collimation System - CERN Document Server