Emittance Growth From Electron Clouds Forming in the LHC Arc Quadrupoles

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In fact, a slow emittance growth is observed in proton bunches at injection energy (450 GeV), showing a bunch-by-bunch signature that is compatible with electron cloud effects. The study of these effects is particularly relevant in view of the planned HL-LHC upgrade, which relies on significantly increased beam intensity and brightness. Particle tracking simulations that take into account both electron cloud effects and the non-linear magnetic fields of the lattice suggest that the electron clouds forming in the arc quadrupoles are responsible for the observed degradation. In this work, the simulation results are studied to gain insight into the mechanism which drives the slow emittance growth. Finally, it is discussed how optimising the optics of the lattice can allow the mitigation of such effects. Paraschou, Konstantinos; Bartosik, Hannes; Deniau, Laurent; Iadarola, Giovanni; Maclean, Ewen; Mether, Lotta; Papaphilippou, Yannis; Pieloni, Tatiana; Potdevin, Joséphine; Rumolo, Giovanni; Tomás García, Rogelio" /> <meta name="keywords" content="simulation, emittance, resonance, optics, electron" /> <script type="text/javascript" src="https://cds.cern.ch/js/jquery.min.js"></script>  <link rel="stylesheet" href="https://cds.cern.ch/img/webnews.css" type="text/css" />  <script type="text/javascript" src="https://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 : Emittance Growth From Electron Clouds Forming in the LHC Arc Quadrupoles" name="citation_title" /> <meta content="Paraschou, Konstantinos" name="citation_author" /> <meta content="Pieloni, Tatiana" name="citation_author" /> <meta content="Deniau, Laurent" name="citation_author" /> <meta content="Rumolo, Giovanni" name="citation_author" /> <meta content="Potdevin, Joséphine" name="citation_author" /> <meta content="Tomás García, Rogelio" name="citation_author" /> <meta content="Iadarola, Giovanni" name="citation_author" /> <meta content="Maclean, Ewen" name="citation_author" /> <meta content="Bartosik, Hannes" name="citation_author" /> <meta content="Mether, Lotta" name="citation_author" /> <meta content="Papaphilippou, Yannis" name="citation_author" /> <meta content="10.18429/JACoW-HB2023-THBP16" name="citation_doi" /> <meta content="JACoW HB" name="citation_journal_title" /> <meta content="2023" name="citation_volume" /> <meta content="487-490" name="citation_firstpage" /> <meta content="2024" name="citation_publication_date" /> <meta name="citation_online_date" content="2024/06/18"> <meta content="10.18429/JACoW-HB2023-THBP16" name="citation_doi" /> <meta name="citation_pdf_url" content="https://cds.cern.ch/record/2901227/files/document.pdf" />  <meta content="JACOW" property="og:title" /> <meta content="Emittance Growth From Electron Clouds Forming in the LHC Arc Quadrupoles" property="og:title" /> <meta content="website" property="og:type" /> <meta content="website" property="og:type" /> <meta content="https://cds.cern.ch/record/2901227" property="og:url" /> <meta content="CERN Document Server" property="og:site_name" /> <meta content="Operation of the Large Hadron Collider with proton bunches spaced 25 ns apart favours the formation of electron clouds. 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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>Emittance Growth From Electron Clouds Forming in the LHC Arc Quadrupoles</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 11 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="https://cds.cern.ch/search?f=author&p=Paraschou%2C%20Konstantinos&ln=en">Paraschou, Konstantinos</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Bartosik%2C%20Hannes&ln=en">Bartosik, Hannes</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Deniau%2C%20Laurent&ln=en">Deniau, Laurent</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Iadarola%2C%20Giovanni&ln=en">Iadarola, Giovanni</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Maclean%2C%20Ewen&ln=en">Maclean, Ewen</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Mether%2C%20Lotta&ln=en">Mether, Lotta</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Papaphilippou%2C%20Yannis&ln=en">Papaphilippou, Yannis</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Pieloni%2C%20Tatiana&ln=en">Pieloni, Tatiana</a> (Ecole Polytechnique, Lausanne) ; <a href="https://cds.cern.ch/search?f=author&p=Potdevin%2C%20Jos%C3%A9phine&ln=en">Potdevin, Joséphine</a> (Ecole Polytechnique, Lausanne) ; <a href="https://cds.cern.ch/search?f=author&p=Rumolo%2C%20Giovanni&ln=en">Rumolo, Giovanni</a> (CERN)<span id="more" style=""> ; <a href="https://cds.cern.ch/search?f=author&p=Tom%C3%A1s%20Garc%C3%ADa%2C%20Rogelio&ln=en">Tomás García, Rogelio</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;">4</td></tr> <tr><td class="formatRecordLabel"> In: </td><td style="padding-left:5px;"><a href="http://dx.doi.org/10.18429/JACoW-HB2023-THBP16"><i>JACoW HB</i> 2023 (2024) 487-490</a> </a></td></tr> <tr><td class="formatRecordLabel"> In: </td><td style="padding-left:5px;"><a href="https://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.487-490</td></tr> <tr><td class="formatRecordLabel"> DOI </td><td style="padding-left:5px;"><a href="http://dx.doi.org/10.18429/JACoW-HB2023-THBP16" title="DOI" target="_blank">10.18429/JACoW-HB2023-THBP16</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;">Operation of the Large Hadron Collider with proton bunches spaced 25 ns apart favours the formation of electron clouds. In fact, a slow emittance growth is observed in proton bunches at injection energy (450 GeV), showing a bunch-by-bunch signature that is compatible with electron cloud effects. The study of these effects is particularly relevant in view of the planned HL-LHC upgrade, which relies on significantly increased beam intensity and brightness. Particle tracking simulations that take into account both electron cloud effects and the non-linear magnetic fields of the lattice suggest that the electron clouds forming in the arc quadrupoles are responsible for the observed degradation. In this work, the simulation results are studied to gain insight into the mechanism which drives the slow emittance growth. Finally, it is discussed how optimising the optics of the lattice can allow the mitigation of such effects.</td></tr> <tr><td class="formatRecordLabel"> Copyright/License </td><td style="padding-left:5px;">© 2024 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/2776129">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 2024-06-18, last modified 2024-06-18</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%3A2901227&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/2901227/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=2901227">Add to personal basket</a></li> <li>Export as <a style="text-decoration:underline;font-weight:normal" href="/record/2901227/export/hx?ln=en">BibTeX</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2901227/export/hm?ln=en">MARC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2901227/export/xm?ln=en">MARCXML</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2901227/export/xd?ln=en">DC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2901227/export/xe?ln=en">EndNote</a>,  <a style="text-decoration:underline;font-weight:normal" href="/record/2901227/export/xn?ln=en">NLM</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2901227/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', 'https://cds.cern.ch/img/sciencewise.png', 'en', 'bookmark', 'http://sciencewise.info/bookmarks/cds:2901227/add'); $('#bookmark_sciencewise').bookmark({sites: ['sciencewise']}); $('#bookmark').bookmark({ sites: ['facebook', 'twitter', 'linkedin', 'google_plusone'], icons: '/img/bookmarks.png', url: 'https://cds.cern.ch/record/2901227', addEmail: true, title: "Emittance Growth From Electron Clouds Forming in the LHC Arc Quadrupoles", description: "Operation\u00a0of\u00a0the Large Hadron Collider with proton bunches spaced 25 ns\u00a0apart\u00a0favours the formation of electron clouds. In fact, a slow emittance growth is observed in proton bunches at injection energy (450 GeV), showing\u00a0a bunch-by-bunch signature that is compatible with electron cloud effects. The study of these effects is particularly relevant in view of the planned HL-LHC upgrade, which relies on significantly increased beam intensity and brightness. Particle tracking simulations\u00a0that take into account\u00a0both electron cloud effects and the non-linear magnetic fields of the lattice\u00a0suggest\u00a0that the electron clouds forming in the arc quadrupoles are responsible for the observed degradation. In this work, the simulation results are studied to gain insight\u00a0into\u00a0the mechanism which drives the slow emittance growth. 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Emittance Growth From Electron Clouds Forming in the LHC Arc Quadrupoles - CERN Document Server