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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">     <html xmlns="http://www.w3.org/1999/xhtml" lang="zh" xml:lang="zh" xmlns:og="http://ogp.me/ns#" xmlns:fb="http://ogp.me/ns/fb#"> <head> <title>Positron Sources for Future High Energy Physics Colliders - CERN Document Server</title> <link href='https://framework.web.cern.ch/framework/2.0/fonts/PTSansWeb/PTSansWeb.css' rel='stylesheet' type='text/css' /> <link rel="stylesheet" href="https://cds.cern.ch/img/invenio.css?v=20141127" type="text/css" /> <link rel="stylesheet" href="https://cds.cern.ch/img/cern_theme/css/cern_theme.css?v=20141127" type="text/css" /> <link rel="stylesheet"href="/css/font-awesome.min.css"> <meta http-equiv="X-UA-Compatible" content="IE=Edge"/> <link rel="stylesheet" href="https://cds.cern.ch/img/cern_toolbar/css/toolbar.css" type="text/css" />    <link rel="canonical" href="https://cds.cern.ch/record/2808057" /> <link rel="alternate" hreflang="el" href="https://cds.cern.ch/record/2808057?ln=el" /> <link rel="alternate" hreflang="fr" href="https://cds.cern.ch/record/2808057?ln=fr" /> <link rel="alternate" hreflang="bg" href="https://cds.cern.ch/record/2808057?ln=bg" /> <link rel="alternate" hreflang="zh-TW" href="https://cds.cern.ch/record/2808057?ln=zh_TW" /> <link rel="alternate" hreflang="pt" href="https://cds.cern.ch/record/2808057?ln=pt" /> <link rel="alternate" hreflang="no" href="https://cds.cern.ch/record/2808057?ln=no" /> <link rel="alternate" hreflang="hr" href="https://cds.cern.ch/record/2808057?ln=hr" /> <link rel="alternate" hreflang="ca" href="https://cds.cern.ch/record/2808057?ln=ca" /> <link rel="alternate" hreflang="de" href="https://cds.cern.ch/record/2808057?ln=de" /> <link rel="alternate" hreflang="it" href="https://cds.cern.ch/record/2808057?ln=it" /> <link rel="alternate" hreflang="zh-CN" href="https://cds.cern.ch/record/2808057?ln=zh_CN" /> <link rel="alternate" hreflang="sv" href="https://cds.cern.ch/record/2808057?ln=sv" /> <link rel="alternate" hreflang="sk" href="https://cds.cern.ch/record/2808057?ln=sk" /> <link rel="alternate" hreflang="en" href="https://cds.cern.ch/record/2808057?ln=en" /> <link rel="alternate" hreflang="pl" href="https://cds.cern.ch/record/2808057?ln=pl" /> <link rel="alternate" hreflang="ru" href="https://cds.cern.ch/record/2808057?ln=ru" /> <link rel="alternate" hreflang="ka" href="https://cds.cern.ch/record/2808057?ln=ka" /> <link rel="alternate" hreflang="ja" href="https://cds.cern.ch/record/2808057?ln=ja" /> <link rel="alternate" hreflang="es" href="https://cds.cern.ch/record/2808057?ln=es" /> <link rel="alternate" type="application/rss+xml" title="CERN Document Server RSS" href="/rss?ln=zh_TW" /> <link rel="search" type="application/opensearchdescription+xml" href="https://cds.cern.ch/opensearchdescription" title="CERN Document Server" /> <link rel="unapi-server" type="application/xml" title="unAPI" href="https://cds.cern.ch/unapi" /> <link rel="apple-touch-icon" href="/apple-touch-icon.png"/> <link rel="apple-touch-icon-precomposed" href="/apple-touch-icon-precomposed.png"/> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <meta http-equiv="Content-Language" content="zh_TW" /> <meta name="description" content="An unprecedented positron average current is required to fit the luminosity demands of future $e^+e^-$ high energy physics colliders. In addition, in order to access precision-frontier physics, these machines require positron polarization to enable exploring the polarization dependence in many HEP processes cross sections, reducing backgrounds and extending the reach of chiral physics studies beyond the standard model. The ILC has a mature plan for the polarized positron source based on conversion in a thin target of circularly polarized gammas generated by passing the main high energy e-beam in a long superconducting helical undulator. Compact colliders (CLIC, C3 and advanced accelerator-based concepts) adopt a simplified approach and currently do not plan to use polarized positrons in their baseline design, but could greatly benefit from the development of compact alternative solutions to polarized positron production. Increasing the positron current, the polarization purity and simplifying the engineering design are all opportunities where advances in accelerator technology have the potential to make a significant impact. This white-paper describes the current status of the field and provides R&D short-term and long-term pathways for polarized positron sources. Musumeci, P.; Boffo, C.; Bulanov, S.S.; Chaikovska, I.; Faus Golfe, A.; Gessner, S.; Grames, J.; Hessami, R.; Ivanyushenkov, Y.; Lankford, A.; Loisch, G.; Moortgat-Pick, G.; Nagaitsev, S.; Riemann, S.; Sievers, P.; Tenholt, C.; Yokoya, K." /> <meta name="keywords" content="CERN Document Server, WebSearch, CERN Document Server" /> <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="arXiv : Positron Sources for Future High Energy Physics Colliders" name="citation_title" /> <meta content="Musumeci, P." name="citation_author" /> <meta content="Faus Golfe, A." name="citation_author" /> <meta content="Ivanyushenkov, Y." name="citation_author" /> <meta content="Gessner, S." name="citation_author" /> <meta content="Lankford, A." name="citation_author" /> <meta content="Sievers, P." name="citation_author" /> <meta content="Yokoya, K." name="citation_author" /> <meta content="Moortgat-Pick, G." name="citation_author" /> <meta content="Grames, J." name="citation_author" /> <meta content="Tenholt, C." name="citation_author" /> <meta content="Boffo, C." name="citation_author" /> <meta content="Loisch, G." name="citation_author" /> <meta content="Bulanov, S.S." name="citation_author" /> <meta content="Nagaitsev, S." name="citation_author" /> <meta content="Hessami, R." name="citation_author" /> <meta content="Riemann, S." name="citation_author" /> <meta content="Chaikovska, I." name="citation_author" /> <meta content="2022/04/27" name="citation_publication_date" /> <meta name="citation_online_date" content="2022/04/30"> <meta content="FERMILAB-CONF-22-372-AD-TD" name="citation_technical_report_number" /> <meta content="arXiv:2204.13245" name="citation_technical_report_number" /> <meta name="citation_pdf_url" content="https://cds.cern.ch/record/2808057/files/2204.13245.pdf" /> <meta name="citation_pdf_url" content="https://cds.cern.ch/record/2808057/files/jt.pdf" />  <meta content="Positron Sources for Future High Energy Physics Colliders" property="og:title" /> <meta content="arXiv" property="og:title" /> <meta content="website" property="og:type" /> <meta content="website" property="og:type" /> <meta content="https://cds.cern.ch/record/2808057" property="og:url" /> <meta name="twitter:image" content="https://cds.cern.ch/record/2808057/files/peter-princ-layout.png" /> <meta property="og:image" content="https://cds.cern.ch/record/2808057/files/peter-princ-layout.png" /> <meta property="og:image:secure_url" content="https://cds.cern.ch/record/2808057/files/peter-princ-layout.png" /> <meta property="og:image" content="https://cds.cern.ch/record/2808057/files/bunchlengthvspos.png" /> <meta property="og:image:secure_url" content="https://cds.cern.ch/record/2808057/files/bunchlengthvspos.png" /> <meta property="og:image" content="https://cds.cern.ch/record/2808057/files/PositronYield.png" /> <meta property="og:image:secure_url" content="https://cds.cern.ch/record/2808057/files/PositronYield.png" /> <meta property="og:image" content="https://cds.cern.ch/record/2808057/files/full_chain.png" /> <meta property="og:image:secure_url" content="https://cds.cern.ch/record/2808057/files/full_chain.png" /> <meta property="og:image" content="https://cds.cern.ch/record/2808057/files/Tdistr-sector.png" /> <meta property="og:image:secure_url" content="https://cds.cern.ch/record/2808057/files/Tdistr-sector.png" /> <meta property="og:image" content="https://cds.cern.ch/record/2808057/files/PEPPo.png" /> <meta property="og:image:secure_url" content="https://cds.cern.ch/record/2808057/files/PEPPo.png" /> <meta property="og:image" content="https://cds.cern.ch/record/2808057/files/PulsedSolenoid_sketch.png" /> <meta property="og:image:secure_url" content="https://cds.cern.ch/record/2808057/files/PulsedSolenoid_sketch.png" /> <meta content="CERN Document Server" property="og:site_name" /> <meta content="arXiv" property="og:description" /> <meta content="An unprecedented positron average current is required to fit the luminosity demands of future $e^+e^-$ high energy physics colliders. In addition, in order to access precision-frontier physics, these machines require positron polarization to enable exploring the polarization dependence in many HEP processes cross sections, reducing backgrounds and extending the reach of chiral physics studies beyond the standard model. The ILC has a mature plan for the polarized positron source based on conversion in a thin target of circularly polarized gammas generated by passing the main high energy e-beam in a long superconducting helical undulator. Compact colliders (CLIC, C3 and advanced accelerator-based concepts) adopt a simplified approach and currently do not plan to use polarized positrons in their baseline design, but could greatly benefit from the development of compact alternative solutions to polarized positron production. Increasing the positron current, the polarization purity and simplifying the engineering design are all opportunities where advances in accelerator technology have the potential to make a significant impact. This white-paper describes the current status of the field and provides R&D; short-term and long-term pathways for polarized positron sources." property="og:description" />  <meta content="summary" name="twitter:card" /> <meta content="summary" name="twitter:card" /> <style></style> </head> <body class="CERN32Document32Server search" lang="zh">  <div id="cern-toolbar"> <h1><a href="http://cern.ch" title="CERN">CERN <span>Accelerating science</span></a></h1> <ul> <li class="cern-accountlinks"><a class="cern-account" href="https://cds.cern.ch/youraccount/login?ln=zh_TW&referer=https%3A//cds.cern.ch/record/2808057%3Fln%3Dzh_TW" title="Sign in to your CERN account">Sign in</a></li> <li><a class="cern-directory" href="http://cern.ch/directory" title="Search CERN resources and browse the directory">Directory</a></li> </ul> </div>   <div role="banner" class="clearfix" id="header"> <div class="header-inner inner"> <hgroup class="clearfix"> <h2 id="site-name"> <a rel="home" title="Home" href="/"><span>CERN Document Server</span></a> </h2> <h3 id="site-slogan">Access articles, reports and multimedia content in HEP</h3> </hgroup> <div role="navigation" id="main-navigation" class="cdsmenu"> <h2 class="element-invisible">Main menu</h2><ul class="links inline clearfix"> <li class="menu-386 first active-trail"><a class="active-trail" href="https://cds.cern.ch/?ln=zh_TW">搜尋</a></li> <li class="menu-444 "><a class="" title="" href="https://cds.cern.ch/submit?ln=zh_TW">提交</a></li> <li class="menu-426 "><a class="" href="https://cds.cern.ch/help/?ln=zh_TW">幫助</a></li> <li class="leaf hassubcdsmenu"> <a hreflang="en" class="header" href="https://cds.cern.ch/youraccount/display?ln=zh_TW">個人化</a> <ul class="subsubcdsmenu"><li><a href="https://cds.cern.ch/youralerts/list?ln=zh_TW">Your alerts</a></li><li><a href="https://cds.cern.ch/yourbaskets/display?ln=zh_TW">Your baskets</a></li><li><a href="https://cds.cern.ch/yourcomments?ln=zh_TW">Your comments</a></li><li><a href="https://cds.cern.ch/youralerts/display?ln=zh_TW">Your searches</a></li></ul></li> </ul> </div> </div> </div>  <table class="navtrailbox"> <tr> <td class="navtrailboxbody"> <a href="/?ln=zh_TW" class="navtrail">主頁</a> > Positron Sources for Future High Energy Physics Colliders </td> </tr> </table> </div> <div class="pagebody"><div class="pagebodystripemiddle"> <div class="detailedrecordbox"> <div class="detailedrecordtabs"> <div> <ul class="detailedrecordtabs"><li class="on first"><a href="/record/2808057/?ln=zh_TW">Information </a></li><li class=""><a href="/record/2808057/files?ln=zh_TW">Files </a></li></ul> <div id="tabsSpacer" style="clear:both;height:0px"> </div></div> </div> <div class="detailedrecordboxcontent"> <div class="top-left-folded"></div> <div class="top-right-folded"></div> <div class="inside">  <abbr class="unapi-id" title="2808057"></abbr>  <link href="/img/download_and_embed_buttons.css" rel="stylesheet" type="text/css" /> <style type="text/css">  .video_talk_wrapper{ max-width: 640px; min-height: 360px; } </style> <table class="formatRecordTableFullWidth"> <tr> <td class="formatRecordHeader" style="background-image: url('/img/journals.jpg');" colspan="2">  Preprint </td> </tr> <tr><td class="formatRecordLabel"> Report number </td><td style="padding-left:5px;"><a href="http://arxiv.org/abs/arXiv:2204.13245">arXiv:2204.13245</a> ; FERMILAB-CONF-22-372-AD-TD</td></tr> <tr><td class="formatRecordLabel"> Title </td><td style="padding-left:5px;"><b>Positron Sources for Future High Energy Physics Colliders</b></td></tr> <style> .video_control_container, #video_controlbutton { display: none; }#video_detailbox_download {display: none;}#video_detailbox_embed {display: none;}</style> <div class="video_control_container"> <div style="box-sizing: inherit;position: relative;min-height: 1em;margin: 1em 0;background: #f8f8f9;padding: 1em 1.5em;line-height: 1.4285em;transition: opacity .1s ease,color .1s ease,background .1s ease,box-shadow .1s ease,-webkit-box-shadow .1s ease;border-radius: .28571429rem;font-size: 1.1em;margin-top: 0;margin-bottom: 6px;background-color: #f8ffff;color: #276f86;box-shadow: 0 0 0 1px #a9d5de inset,0 0 0 0 transparent;"> <i class="fa fa-info"></i><span style="padding-left: 9px;">If you experience any problem watching the video, click the download button below</span> </div> <a id="video_controlbutton_download" rel="download_button" class="video_controlbutton" href="#">Download</a> <a id="video_controlbutton_embed" class="video_controlbutton" href="#">Embed</a> </div> <div id="video_detailbox_download" style="margin:10px"> </div> <div id="video_detailbox_embed" style="margin:10px"> </div> <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 = "隱藏" } else { more.style.display = 'none'; extension.style.display = ''; link.innerHTML = "顯示全部 17 名作者" } 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=Musumeci%2C%20P.&ln=zh_TW">Musumeci, P.</a> (UCLA) ; <a href="https://cds.cern.ch/search?f=author&p=Boffo%2C%20C.&ln=zh_TW">Boffo, C.</a> (Fermilab) ; <a href="https://cds.cern.ch/search?f=author&p=Bulanov%2C%20S.S.&ln=zh_TW">Bulanov, S.S.</a> (LBL, Berkeley) ; <a href="https://cds.cern.ch/search?f=author&p=Chaikovska%2C%20I.&ln=zh_TW">Chaikovska, I.</a> (IJCLab, Orsay) ; <a href="https://cds.cern.ch/search?f=author&p=Faus%20Golfe%2C%20A.&ln=zh_TW">Faus Golfe, A.</a> (IJCLab, Orsay) ; <a href="https://cds.cern.ch/search?f=author&p=Gessner%2C%20S.&ln=zh_TW">Gessner, S.</a> (SLAC) ; <a href="https://cds.cern.ch/search?f=author&p=Grames%2C%20J.&ln=zh_TW">Grames, J.</a> (Jefferson Lab) ; <a href="https://cds.cern.ch/search?f=author&p=Hessami%2C%20R.&ln=zh_TW">Hessami, R.</a> (Stanford U.) ; <a href="https://cds.cern.ch/search?f=author&p=Ivanyushenkov%2C%20Y.&ln=zh_TW">Ivanyushenkov, Y.</a> (Argonne, PHY) ; <a href="https://cds.cern.ch/search?f=author&p=Lankford%2C%20A.&ln=zh_TW">Lankford, A.</a> (UC, Irvine)<span id="more" style=""> ; <a href="https://cds.cern.ch/search?f=author&p=Loisch%2C%20G.&ln=zh_TW">Loisch, G.</a> (DESY) ; <a href="https://cds.cern.ch/search?f=author&p=Moortgat-Pick%2C%20G.&ln=zh_TW">Moortgat-Pick, G.</a> (DESY ; Hamburg U.) ; <a href="https://cds.cern.ch/search?f=author&p=Nagaitsev%2C%20S.&ln=zh_TW">Nagaitsev, S.</a> (Fermilab ; Chicago U.) ; <a href="https://cds.cern.ch/search?f=author&p=Riemann%2C%20S.&ln=zh_TW">Riemann, S.</a> (DESY) ; <a href="https://cds.cern.ch/search?f=author&p=Sievers%2C%20P.&ln=zh_TW">Sievers, P.</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Tenholt%2C%20C.&ln=zh_TW">Tenholt, C.</a> (HZDR, Dresden) ; <a href="https://cds.cern.ch/search?f=author&p=Yokoya%2C%20K.&ln=zh_TW">Yokoya, K.</a> (KEK, Tsukuba)</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>  <script type="text/javascript"> /* * Changes the Imprint title to Date - Duration as requested by RQF0820114 * This is a hack not to touch the general imprint format element */ $(document).ready(function() { var collections = 'ConferencePaper ; PREPRINT'; if (collections.indexOf('E-LEARNING') > -1) { $('.cern-imprint-label').text('Date - Duration'); } }) </script> <tr><td class="formatRecordLabel cern-imprint-label"> Imprint </td><td style="padding-left:5px;">2022-04-27</td></tr> <tr><td class="formatRecordLabel"> Number of pages </td><td style="padding-left:5px;">26</td></tr>  <tr><td class="formatRecordLabel"> Note </td><td style="padding-left:5px;">contribution to Snowmass 2021</td></tr> <tr><td class="formatRecordLabel"> Presented at </td><td style="padding-left:5px;"><a href="https://cds.cern.ch/record/2722743">2021 Snowmass Summer Study</a>, Seattle, WA, United States, 11 - 20 July 2021, pp.</td></tr> <tr><td class="formatRecordLabel"> Subject category </td><td style="padding-left:5px;">physics.acc-ph ; Accelerators and Storage Rings</td></tr> <tr><td class="formatRecordLabel"> Abstract </td><td style="padding-left:5px;">An unprecedented positron average current is required to fit the luminosity demands of future $e^+e^-$ high energy physics colliders. In addition, in order to access precision-frontier physics, these machines require positron polarization to enable exploring the polarization dependence in many HEP processes cross sections, reducing backgrounds and extending the reach of chiral physics studies beyond the standard model. The ILC has a mature plan for the polarized positron source based on conversion in a thin target of circularly polarized gammas generated by passing the main high energy e-beam in a long superconducting helical undulator. Compact colliders (CLIC, C3 and advanced accelerator-based concepts) adopt a simplified approach and currently do not plan to use polarized positrons in their baseline design, but could greatly benefit from the development of compact alternative solutions to polarized positron production. Increasing the positron current, the polarization purity and simplifying the engineering design are all opportunities where advances in accelerator technology have the potential to make a significant impact. This white-paper describes the current status of the field and provides R&D; short-term and long-term pathways for polarized positron sources.</td></tr> <tr><td class="formatRecordLabel"> Other source </td><td style="padding-left:5px;"><a href="http://inspirehep.net/record/2074254">Inspire</a></td></tr> <tr><td class="formatRecordLabel"> Copyright/License </td><td style="padding-left:5px;">preprint: (License: <a href="http://creativecommons.org/licenses/by/4.0/">CC BY 4.0</a>)</td></tr> </table> <br /><div style="max-width:1024px;margin:auto"><div style="overflow-x:auto;display:inline;width:100%;"><a href="/record/2808057/plots#0"><img style="vertical-align:middle;" src="https://cds.cern.ch/record/2808057/files/full_chain.png" title=" Different sub-systems of the positron source basic scheme." width="200px"/></a> <a href="/record/2808057/plots#1"><img style="vertical-align:middle;" src="https://cds.cern.ch/record/2808057/files/Tdistr-sector.png" title=" Average temperature distribution in the target shown for a sector corresponding to 1 pulse length (0.73\,ms) at ILC250; the beam impinges on the target at r=50~cm. The emissivities of target and cooler surface are 0.5 corresponding to an effective emissivity of $\varepsilon = 0.33$." width="200px"/></a> <a href="/record/2808057/plots#2"><img style="vertical-align:middle;" src="https://cds.cern.ch/record/2808057/files/peter-princ-layout.png" title=" Principal Layout of the rotating wheel showing its main components: its cooling system, its rotating magnetic bearing and the matching device (AMD)." width="200px"/></a> <a href='/record/2808057/plots'>Show more plots</a></div></div><br /> <br/><div><div style="clear: both;"> </div></div> <script type="text/javascript"> // Initially hide: $(".longCaption").hide(); // Allow to toggle visibility: $(".toggleLongCaption").toggle(function(){ $(this).siblings(".longCaption").show('fast'); var thisElem = $(this); thisElem.text(thisElem.text() === "更多" ? "less" : "更多"); },function(){ $(this).siblings(".longCaption").hide('fast'); var thisElem = $(this); thisElem.text(thisElem.text() === "更多" ? 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In addition, in order to access precision-frontier physics, these machines require positron polarization to enable exploring the polarization dependence in many HEP processes cross sections, reducing backgrounds and extending the reach of chiral physics studies beyond the standard model. The ILC has a mature plan for the polarized positron source based on conversion in a thin target of circularly polarized gammas generated by passing the main high energy e-beam in a long superconducting helical undulator. Compact colliders (CLIC, C3 and advanced accelerator-based concepts) adopt a simplified approach and currently do not plan to use polarized positrons in their baseline design, but could greatly benefit from the development of compact alternative solutions to polarized positron production. Increasing the positron current, the polarization purity and simplifying the engineering design are all opportunities where advances in accelerator technology have the potential to make a significant impact. This white-paper describes the current status of the field and provides R&D short-term and long-term pathways for polarized positron sources." }); // ]]> </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=zh_TW">搜尋</a> :: <a class="footer" href="https://cds.cern.ch/submit?ln=zh_TW">提交</a> :: <a class="footer" href="https://cds.cern.ch/youraccount/display?ln=zh_TW">個人化</a> :: <a class="footer" href="https://cds.cern.ch/help/?ln=zh_TW">幫助</a> :: <a class="footer" href="https://cern.service-now.com/service-portal?id=privacy_policy&se=CDS-Service" target="_blank">Privacy Notice</a> <br /> 伺服器系統： <a class="footer" href="http://invenio-software.org/">Invenio</a> <br /> 管理者： <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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