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Efthymiopoulos, Ilias; Wegscheider, Andreas; Mirarchi, Daniele; Maclean, Ewen; Carlier, Felix; Van der Veken, Frederik; Dilly, Joschua; Le Garrec, Mael; D'Andrea, Marco; Solfaroli, Matteo; Bruce, Roderik; Tomas, Rogelio; Horney, Sasha; Redaelli, Stefano; Fartoukh, Stephane; Persson, Tobias; Ferrentino, Vittorio" /> <meta name="keywords" content="optics, experiment, collimation, detector, luminosity, bunching" /> <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 : Evolution of special LHC optics configurations Run 3 update" name="citation_title" /> <meta content="Efthymiopoulos, Ilias" name="citation_author" /> <meta content="Tomas, Rogelio" name="citation_author" /> <meta content="Carlier, Felix" name="citation_author" /> <meta content="Le Garrec, Mael" name="citation_author" /> <meta content="D'Andrea, Marco" name="citation_author" /> <meta content="Mirarchi, Daniele" name="citation_author" /> <meta content="Wegscheider, Andreas" name="citation_author" /> <meta content="Fartoukh, Stephane" name="citation_author" /> <meta content="Bruce, Roderik" name="citation_author" /> <meta content="Redaelli, Stefano" name="citation_author" /> <meta content="Van der Veken, Frederik" name="citation_author" /> <meta content="Maclean, Ewen" name="citation_author" /> <meta content="Ferrentino, Vittorio" name="citation_author" /> <meta content="Dilly, Joschua" name="citation_author" /> <meta content="Solfaroli, Matteo" name="citation_author" /> <meta content="Persson, Tobias" name="citation_author" /> <meta content="Horney, Sasha" name="citation_author" /> <meta content="10.18429/JACoW-IPAC2024-MOPC16" name="citation_doi" /> <meta content="JACoW IPAC" name="citation_journal_title" /> <meta content="2024" name="citation_volume" /> <meta content="MOPC16" name="citation_firstpage" /> <meta content="2024" name="citation_publication_date" /> <meta name="citation_online_date" content="2024/10/04"> <meta content="10.18429/JACoW-IPAC2024-MOPC16" name="citation_doi" /> <meta name="citation_pdf_url" content="https://cds.cern.ch/record/2912361/files/document.pdf" />  <meta content="JACOW" property="og:title" /> <meta content="Evolution of special LHC optics configurations Run 3 update" property="og:title" /> <meta content="website" property="og:type" /> <meta content="website" property="og:type" /> <meta content="https://cds.cern.ch/record/2912361" property="og:url" /> <meta content="CERN Document Server" property="og:site_name" /> <meta content="The Large Hadron Collider (LHC) employs special optics and configurations, alongside low-beta* collision optics, to address specific experimental requirements. 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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>Evolution of special LHC optics configurations Run 3 update</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 17 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=Efthymiopoulos%2C%20Ilias&ln=en">Efthymiopoulos, Ilias</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Wegscheider%2C%20Andreas&ln=en">Wegscheider, Andreas</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Mirarchi%2C%20Daniele&ln=en">Mirarchi, Daniele</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=Carlier%2C%20Felix&ln=en">Carlier, Felix</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Van%20der%20Veken%2C%20Frederik&ln=en">Van der Veken, Frederik</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Dilly%2C%20Joschua&ln=en">Dilly, Joschua</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Le%20Garrec%2C%20Mael&ln=en">Le Garrec, Mael</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=D%27Andrea%2C%20Marco&ln=en">D'Andrea, Marco</a> (CERN ; INFN, Legnaro) ; <a href="https://cds.cern.ch/search?f=author&p=Solfaroli%2C%20Matteo&ln=en">Solfaroli, Matteo</a> (CERN)<span id="more" style=""> ; <a href="https://cds.cern.ch/search?f=author&p=Bruce%2C%20Roderik&ln=en">Bruce, Roderik</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Tomas%2C%20Rogelio&ln=en">Tomas, Rogelio</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Horney%2C%20Sasha&ln=en">Horney, Sasha</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Redaelli%2C%20Stefano&ln=en">Redaelli, Stefano</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Fartoukh%2C%20Stephane&ln=en">Fartoukh, Stephane</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Persson%2C%20Tobias&ln=en">Persson, Tobias</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Ferrentino%2C%20Vittorio&ln=en">Ferrentino, Vittorio</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-IPAC2024-MOPC16"><i>JACoW IPAC</i> 2024 (2024) MOPC16</a> </a></td></tr> <tr><td class="formatRecordLabel"> In: </td><td style="padding-left:5px;"><a href="https://cds.cern.ch/record/2903046">15th International Particle Accelerator Conference (IPAC 2024)</a>, Nashville, TN, United States, 19 - 24 May 2024, pp.MOPC16</td></tr> <tr><td class="formatRecordLabel"> DOI </td><td style="padding-left:5px;"><a href="http://dx.doi.org/10.18429/JACoW-IPAC2024-MOPC16" title="DOI" target="_blank">10.18429/JACoW-IPAC2024-MOPC16</a> <tr><td class="formatRecordLabel"> Subject category </td><td style="padding-left:5px;">Accelerators and Storage Rings</td></tr> <tr><td class="formatRecordLabel"> Accelerator/Facility, Experiment </td><td style="padding-left:5px;"><a href="https://cds.cern.ch/search?p=CERN%20LHC&f=693__a">CERN LHC</a></td></tr> <tr><td class="formatRecordLabel"> Abstract </td><td style="padding-left:5px;">The Large Hadron Collider (LHC) employs special optics and configurations, alongside low-beta* collision optics, to address specific experimental requirements. These include calibrating luminosity monitors (vdM) and facilitating forward physics measurements in TOTEM and ALFA experiments (high-beta). The special optics have been in use since Run 1, and for Run 3, they have been updated for compatibility with standard low-beta collision optics to ensure streamlined commissioning and reduced setup time. For vdM optics in Run 3, beam de-squeezing yields beta* values of 19 to 24 m, while in the high-beta optics, beams are de-squeezed to round beams with beta* of 120 m, followed by a second step to asymmetric optics with beta* of 3 km and 6 km in the horizontal and vertical planes. The 2023 high-beta optics run with the km beta* optics, incorporates tight collimation settings and the use of crystals at top energy for the first time, aiming to substantially reduce backgrounds in the experiments. This publication introduces and discusses the updated optics for Run 3, covering their validation, optics measurement results, and operational insights.</td></tr> <tr><td class="formatRecordLabel"> Copyright/License </td><td style="padding-left:5px;"><a href="https://creativecommons.org/licenses/by/4.0">CC-BY-4.0</a></td></tr> </table> <br/>Corresponding record in: <a href="http://inspirehep.net/record/2813111">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 2024-10-04, last modified 2024-10-04</div></div> <div class="bottom-right-folded" style="text-align:right;padding-bottom:2px;"> <span class="moreinfo" style="margin-right:10px;"></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/2912361/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=2912361">Add to personal basket</a></li> <li>Export as <a style="text-decoration:underline;font-weight:normal" href="/record/2912361/export/hx?ln=en">BibTeX</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2912361/export/hm?ln=en">MARC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2912361/export/xm?ln=en">MARCXML</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2912361/export/xd?ln=en">DC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2912361/export/xe?ln=en">EndNote</a>,  <a style="text-decoration:underline;font-weight:normal" href="/record/2912361/export/xn?ln=en">NLM</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2912361/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:2912361/add'); $('#bookmark_sciencewise').bookmark({sites: ['sciencewise']}); $('#bookmark').bookmark({ sites: ['facebook', 'twitter', 'linkedin', 'google_plusone'], icons: '/img/bookmarks.png', url: 'https://cds.cern.ch/record/2912361', addEmail: true, title: "Evolution of special LHC optics configurations Run 3 update", description: "The Large Hadron Collider (LHC) employs special optics and configurations, alongside low-beta* collision optics, to address specific experimental requirements. These include calibrating luminosity monitors (vdM) and facilitating forward physics measurements in TOTEM and ALFA experiments (high-beta). The special optics have been in use since Run 1, and for Run 3, they have been updated for compatibility with standard low-beta collision optics to ensure streamlined commissioning and reduced setup time. For vdM optics in Run 3, beam de-squeezing yields beta* values of 19 to 24 m, while in the high-beta optics, beams are de-squeezed to round beams with beta* of 120 m, followed by a second step to asymmetric optics with beta* of 3 km and 6 km in the horizontal and vertical planes. The 2023 high-beta optics run with the km beta* optics, incorporates tight collimation settings and the use of crystals at top energy for the first time, aiming to substantially reduce backgrounds in the experiments. This publication introduces and discusses the updated optics for Run 3, covering their validation, optics measurement results, and operational insights." }); // ]]> </script>  </div> </div> <div style="clear:both;margin-bottom: 0;"></div> </div> <div class="bottom-left"></div><div class="bottom-right"></div> </div> </div></div> <footer id="footer" class="pagefooter clearfix">  <div class="pagefooterstripeleft"> CERN Document Server :: <a class="footer" href="https://cds.cern.ch/?ln=en">Search</a> :: <a class="footer" href="https://cds.cern.ch/submit?ln=en">Submit</a> :: <a class="footer" href="https://cds.cern.ch/youraccount/display?ln=en">Personalize</a> :: <a class="footer" href="https://cds.cern.ch/help/?ln=en">Help</a> :: <a class="footer" href="https://cern.service-now.com/service-portal?id=privacy_policy&se=CDS-Service" target="_blank">Privacy Notice</a> :: <a class="footer" href="https://repository.cern/content-policy" target="_blank">Content Policy</a> :: <a class="footer" href="https://repository.cern/terms" target="_blank">Terms and Conditions</a> <br /> Powered by <a class="footer" href="http://invenio-software.org/">Invenio</a> <br /> Maintained by <a class="footer" href="https://cern.service-now.com/service-portal?id=service_element&name=CDS-Service">CDS Service</a> - Need help? 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