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The automatic tuning system, however, needs time for the mechanical compensation of the resonance frequency to take place. Acting back on the beam, the transients in RF power are expected to limit the maximum injected intensity by generating unacceptable beam loss. Reducing them is therefore essential to reach the target intensity during the High Luminosity (HL) LHC era. At LHC flat bottom, the cavities are operated using the half-detuning beam-loading compensation scheme. As implemented today, the tuner control algorithm starts acting only after the injection of the first longer bunch train which causes the bunches for this injection to experience the largest power spikes. This contribution presents an adapted detuning scheme for the RF cavities before injection. It was proposed as a path to decrease the transients, hence increasing the available intensity margin for the available RF power. The expected gain is evaluated in particle tracking simulations and measurements acquired during operation. 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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>Effects of Cavity Pre-Detuning on RF Power Transients at Injection into the LHC</b></td></tr> <tr><td class="formatRecordLabel"><span style="white-space:nowrap;"> Author(s) </span> </td><td style="padding-left:5px;"><a href="https://cds.cern.ch/search?f=author&p=Karlsen-B%C3%A6ck%2C%20Birk%20Emil&ln=hr">Karlsen-Bæck, Birk Emil</a> (CERN ; Rome U.) ; <a href="https://cds.cern.ch/search?f=author&p=Argyropoulos%2C%20Theodoros&ln=hr">Argyropoulos, Theodoros</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Butterworth%2C%20Andrew&ln=hr">Butterworth, Andrew</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Calaga%2C%20Rama&ln=hr">Calaga, Rama</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Karpov%2C%20Ivan&ln=hr">Karpov, Ivan</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Timko%2C%20Helga&ln=hr">Timko, Helga</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Zampetakis%2C%20Michail&ln=hr">Zampetakis, Michail</a> (CERN)</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-THBP29"><i>JACoW HB</i> 2023 (2024) 530-533</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.530-533</td></tr> <tr><td class="formatRecordLabel"> DOI </td><td style="padding-left:5px;"><a href="http://dx.doi.org/10.18429/JACoW-HB2023-THBP29" title="DOI" target="_blank">10.18429/JACoW-HB2023-THBP29</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;">At injection into the LHC, the RF system is perturbed by beam-induced voltage resulting in strong RF power transients and the instant detuning of the cavities. The automatic tuning system, however, needs time for the mechanical compensation of the resonance frequency to take place. Acting back on the beam, the transients in RF power are expected to limit the maximum injected intensity by generating unacceptable beam loss. Reducing them is therefore essential to reach the target intensity during the High Luminosity (HL) LHC era. At LHC flat bottom, the cavities are operated using the half-detuning beam-loading compensation scheme. As implemented today, the tuner control algorithm starts acting only after the injection of the first longer bunch train which causes the bunches for this injection to experience the largest power spikes. This contribution presents an adapted detuning scheme for the RF cavities before injection. It was proposed as a path to decrease the transients, hence increasing the available intensity margin for the available RF power. The expected gain is evaluated in particle tracking simulations and measurements acquired during operation.</td></tr> <tr><td class="formatRecordLabel"> Copyright/License </td><td style="padding-left:5px;"><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/2776123">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"> Zapis kreiran 2024-12-06, zadnja izmjena 2024-12-06</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=hr&p=recid%3A2918955&rm=wrd" class="moreinfo">Slični zapisi</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">Cjeloviti tekst:</small> <br /><a href="/record/2918955/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=hr&recid=2918955">Add to personal basket</a></li> <li>Export as <a style="text-decoration:underline;font-weight:normal" href="/record/2918955/export/hx?ln=hr">BibTeX</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2918955/export/hm?ln=hr">MARC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2918955/export/xm?ln=hr">MARCXML</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2918955/export/xd?ln=hr">DC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2918955/export/xe?ln=hr">EndNote</a>,  <a style="text-decoration:underline;font-weight:normal" href="/record/2918955/export/xn?ln=hr">NLM</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2918955/export/xw?ln=hr">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:2918955/add'); $('#bookmark_sciencewise').bookmark({sites: ['sciencewise']}); $('#bookmark').bookmark({ sites: ['facebook', 'twitter', 'linkedin', 'google_plusone'], icons: '/img/bookmarks.png', url: 'https://cds.cern.ch/record/2918955', addEmail: true, title: "Effects of Cavity Pre-Detuning on RF Power Transients at Injection into the LHC", description: "At injection into the LHC, the RF system is perturbed by beam-induced voltage resulting in strong RF power transients and the instant detuning of the cavities. 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