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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. 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"/>  <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. 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. 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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. 002900905 540__ $$aCC-BY-3.0$$bJACOW$$uhttps://creativecommons.org/licenses/by/3.0 002900905 542__ $$dthe author(s)$$g2024 002900905 65017 $$2SzGeCERN$$aAccelerators and Storage Rings 002900905 6531_ $$9author$$aoptics 002900905 6531_ $$9author$$aimpedance 002900905 6531_ $$9author$$acollimation 002900905 6531_ $$9author$$asimulation 002900905 6531_ $$9author$$aexperiment 002900905 690C_ $$aARTICLE 002900905 690C_ $$aCERN 002900905 700__ $$aBruce, Roderik$$jJACoW-00011524$$uCERN 002900905 700__ $$aBuffat, Xavier$$jJACoW-00046847$$uCERN 002900905 700__ $$aDe Maria, Riccardo$$jJACoW-00019517$$uCERN 002900905 700__ $$aGiacomel, Lorenzo$$jJACoW-00127032$$uCERN 002900905 700__ $$aHermes, Pascal$$jJACoW-00074053$$uCERN 002900905 700__ $$aMirarchi, Daniele$$jJACoW-00044537$$uCERN 002900905 700__ $$aMounet, Nicolas$$jJACoW-00042877$$uCERN 002900905 700__ $$aPersson, Tobias$$jJACoW-00051579$$uCERN 002900905 700__ $$aRedaelli, Stefano$$jJACoW-00001564$$uCERN 002900905 700__ $$aTomás García, Rogelio$$jJACoW-00003672$$uCERN 002900905 700__ $$aVan der Veken, Frederik$$jJACoW-00094882$$uCERN 002900905 700__ $$aWegscheider, Andreas$$jJACoW-00099515$$uCERN 002900905 773__ $$c183-187$$pJACoW HB$$qHB2023$$v2023$$wC23-10-09.3$$y2024 002900905 8564_ $$82537783$$s3204686$$uhttp://cds.cern.ch/record/2900905/files/document.pdf$$yFulltext 002900905 960__ $$a13 002900905 962__ $$b2895374$$k183-187$$ncern20231009 002900905 980__ $$aARTICLE 002900905 980__ $$aConferencePaper</pre></div></div> <footer id="footer" class="pagefooter clearfix">  <div class="pagefooterstripeleft"> CERN Document Server :: <a class="footer" href="http://cds.cern.ch/?ln=sk">Hľadaj</a> :: <a class="footer" href="http://cds.cern.ch/submit?ln=sk">Pridaj</a> :: <a class="footer" href="https://cds.cern.ch/youraccount/display?ln=sk">Personalizácia</a> :: <a class="footer" href="http://cds.cern.ch/help/?ln=sk">Pomoc</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 /> Spravuje <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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