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Details of both the construction and performance are included. Prominence is given to both the new and the improved features, with respect to the original ALPHA assembly, of the apparatus including a stand-alone antiproton catching trap, the traps used to mix antiparticles to produce the anti-atoms, the magnetic atom trap used to hold some of them, and access for laser light to facilitate excitation of the antihydrogen 1S-2P and 1S-2S transitions. 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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>The ALPHA-2 apparatus - facilitating experimentation with trapped antihydrogen</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 61 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=Akbari%2C%20R&ln=en">Akbari, R</a> (British Columbia U.) ; <a href="https://cds.cern.ch/search?f=author&p=Alves%2C%20B%20X%20R&ln=en">Alves, B X R</a> (Aarhus U.) ; <a href="https://cds.cern.ch/search?f=author&p=Baker%2C%20C%20J&ln=en">Baker, C J</a> (Swansea U.) ; <a href="https://cds.cern.ch/search?f=author&p=Baquero-Ruiz%2C%20M&ln=en">Baquero-Ruiz, M</a> (LPHE, Lausanne) ; <a href="https://cds.cern.ch/search?f=author&p=Bertsche%2C%20W&ln=en">Bertsche, W</a> (Cockcroft Inst. Accel. Sci. Tech. ; Manchester U.) ; <a href="https://cds.cern.ch/search?f=author&p=Butler%2C%20E&ln=en">Butler, E</a> (CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Burrows%2C%20C&ln=en">Burrows, C</a> (Swansea U.) ; <a href="https://cds.cern.ch/search?f=author&p=Capra%2C%20A&ln=en">Capra, A</a> (TRIUMF) ; <a href="https://cds.cern.ch/search?f=author&p=Cesar%2C%20C%20L&ln=en">Cesar, C L</a> (Rio de Janeiro Federal U.) ; <a href="https://cds.cern.ch/search?f=author&p=Charlton%2C%20M&ln=en">Charlton, M</a> (Swansea U.)<span id="more" style=""> ; <a href="https://cds.cern.ch/search?f=author&p=Collister%2C%20R&ln=en">Collister, R</a> (TRIUMF) ; <a href="https://cds.cern.ch/search?f=author&p=Cridland%2C%20A&ln=en">Cridland, A</a> (Swansea U.) ; <a href="https://cds.cern.ch/search?f=author&p=Eriksson%2C%20S&ln=en">Eriksson, S</a> (Swansea U.) ; <a href="https://cds.cern.ch/search?f=author&p=Evans%2C%20A&ln=en">Evans, A</a> (Calgary U.) ; <a href="https://cds.cern.ch/search?f=author&p=Evans%2C%20L%20T&ln=en">Evans, L T</a> (UC, Berkeley) ; <a href="https://cds.cern.ch/search?f=author&p=Evetts%2C%20N&ln=en">Evetts, N</a> (British Columbia U.) ; <a href="https://cds.cern.ch/search?f=author&p=Fajans%2C%20J&ln=en">Fajans, J</a> (UC, Berkeley) ; <a href="https://cds.cern.ch/search?f=author&p=Friesen%2C%20T&ln=en">Friesen, T</a> (Aarhus U. ; Calgary U.) ; <a href="https://cds.cern.ch/search?f=author&p=Fujiwara%2C%20M%20C&ln=en">Fujiwara, M C</a> (TRIUMF) ; <a href="https://cds.cern.ch/search?f=author&p=Gill%2C%20D%20R&ln=en">Gill, D R</a> (TRIUMF) ; <a href="https://cds.cern.ch/search?f=author&p=Grandemange%2C%20P&ln=en">Grandemange, P</a> (TRIUMF ; Calgary U.) ; <a href="https://cds.cern.ch/search?f=author&p=Granum%2C%20P&ln=en">Granum, P</a> (Aarhus U.) ; <a href="https://cds.cern.ch/search?f=author&p=Gutierrez%2C%20A&ln=en">Gutierrez, A</a> (British Columbia U.) ; <a href="https://cds.cern.ch/search?f=author&p=Hangst%2C%20J%20S&ln=en">Hangst, J S</a> (Aarhus U.) ; <a href="https://cds.cern.ch/search?f=author&p=Hayden%2C%20M%20E&ln=en">Hayden, M E</a> (Simon Fraser U.) ; <a href="https://cds.cern.ch/search?f=author&p=Hodgkinson%2C%20D&ln=en">Hodgkinson, D</a> (UC, Berkeley ; Manchester U.) ; <a href="https://cds.cern.ch/search?f=author&p=Isaac%2C%20C%20A&ln=en">Isaac, C A</a> (Swansea U.) ; <a href="https://cds.cern.ch/search?f=author&p=Ishida%2C%20A&ln=en">Ishida, A</a> (Tokyo U.) ; <a href="https://cds.cern.ch/search?f=author&p=Johnson%2C%20M%20A&ln=en">Johnson, M A</a> (Cockcroft Inst. Accel. Sci. Tech. ; Manchester U.) ; <a href="https://cds.cern.ch/search?f=author&p=Jones%2C%20J%20M&ln=en">Jones, J M</a> (Swansea U.) ; <a href="https://cds.cern.ch/search?f=author&p=Jones%2C%20S%20A&ln=en">Jones, S A</a> (Swansea U. ; U. Groningen, VSI) ; <a href="https://cds.cern.ch/search?f=author&p=Jonsell%2C%20S&ln=en">Jonsell, S</a> (Stockholm U. (main)) ; <a href="https://cds.cern.ch/search?f=author&p=Khramov%2C%20A&ln=en">Khramov, A</a> (TRIUMF) ; <a href="https://cds.cern.ch/search?f=author&p=Kurchaninov%2C%20L&ln=en">Kurchaninov, L</a> (TRIUMF) ; <a href="https://cds.cern.ch/search?f=author&p=Little%2C%20A&ln=en">Little, A</a> (UC, Berkeley) ; <a href="https://cds.cern.ch/search?f=author&p=Madsen%2C%20N&ln=en">Madsen, N</a> (Swansea U.) ; <a href="https://cds.cern.ch/search?f=author&p=Maxwell%2C%20D&ln=en">Maxwell, D</a> (Swansea U.) ; <a href="https://cds.cern.ch/search?f=author&p=McKenna%2C%20J%20T%20K&ln=en">McKenna, J T K</a> (TRIUMF) ; <a href="https://cds.cern.ch/search?f=author&p=Menary%2C%20S&ln=en">Menary, S</a> (York U., Canada) ; <a href="https://cds.cern.ch/search?f=author&p=Michan%2C%20J%20M&ln=en">Michan, J M</a> (TRIUMF ; LPHE, Lausanne) ; <a href="https://cds.cern.ch/search?f=author&p=Momose%2C%20T&ln=en">Momose, T</a> (British Columbia U.) ; <a href="https://cds.cern.ch/search?f=author&p=Mullan%2C%20P%20S&ln=en">Mullan, P S</a> (Swansea U. ; Zurich, ETH) ; <a href="https://cds.cern.ch/search?f=author&p=Olchanski%2C%20K&ln=en">Olchanski, K</a> (TRIUMF) ; <a href="https://cds.cern.ch/search?f=author&p=Olin%2C%20A&ln=en">Olin, A</a> (TRIUMF ; Victoria U.) ; <a href="https://cds.cern.ch/search?f=author&p=Peszka%2C%20J&ln=en">Peszka, J</a> (Zurich, ETH ; Swansea U.) ; <a href="https://cds.cern.ch/search?f=author&p=Povilus%2C%20A&ln=en">Povilus, A</a> (LLNL, Livermore) ; <a href="https://cds.cern.ch/search?f=author&p=Powell%2C%20A&ln=en">Powell, A</a> (Calgary U.) ; <a href="https://cds.cern.ch/search?f=author&p=Pusa%2C%20P&ln=en">Pusa, P</a> (Liverpool U.) ; <a href="https://cds.cern.ch/search?f=author&p=Rasmussen%2C%20C%20%C3%98&ln=en">Rasmussen, C Ø</a> (Aarhus U. ; CERN) ; <a href="https://cds.cern.ch/search?f=author&p=Sacramento%2C%20R%20L&ln=en">Sacramento, R L</a> (Rio de Janeiro Federal U.) ; <a href="https://cds.cern.ch/search?f=author&p=Sameed%2C%20M&ln=en">Sameed, M</a> (Swansea U. ; Manchester U.) ; <a href="https://cds.cern.ch/search?f=author&p=Sarid%2C%20E&ln=en">Sarid, E</a> (Soreq Nucl. Res. Ctr. ; Ben Gurion U. of Negev) ; <a href="https://cds.cern.ch/search?f=author&p=Silveira%2C%20D%20M&ln=en">Silveira, D M</a> (Rio de Janeiro Federal U.) ; <a href="https://cds.cern.ch/search?f=author&p=So%2C%20C&ln=en">So, C</a> (TRIUMF ; Calgary U.) ; <a href="https://cds.cern.ch/search?f=author&p=Stracka%2C%20S&ln=en">Stracka, S</a> (Pisa U. ; INFN, Pisa) ; <a href="https://cds.cern.ch/search?f=author&p=Stutter%2C%20G&ln=en">Stutter, G</a> (Aarhus U.) ; <a href="https://cds.cern.ch/search?f=author&p=Tharp%2C%20T%20D&ln=en">Tharp, T D</a> (Marquette U.) ; <a href="https://cds.cern.ch/search?f=author&p=Thompson%2C%20R%20I&ln=en">Thompson, R I</a> (Calgary U.) ; <a href="https://cds.cern.ch/search?f=author&p=Torkzaban%2C%20C&ln=en">Torkzaban, C</a> (UC, Berkeley) ; <a href="https://cds.cern.ch/search?f=author&p=van%20der%20Werf%2C%20D%20P&ln=en">van der Werf, D P</a> (Swansea U.) ; <a href="https://cds.cern.ch/search?f=author&p=Wurtele%2C%20J%20S&ln=en">Wurtele, J S</a> (UC, Berkeley)</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;">2025</td></tr> <tr><td class="formatRecordLabel"> Number of pages </td><td style="padding-left:5px;">24</td></tr> <tr><td class="formatRecordLabel"> In: </td><td style="padding-left:5px;"><a href="http://dx.doi.org/10.1016/j.nima.2024.170194"><i>Nucl. Instrum. Methods Phys. Res., A</i> 1072 (2025) 170194</a> </a></td></tr> <tr><td class="formatRecordLabel"> DOI </td><td style="padding-left:5px;"><a href="http://dx.doi.org/10.1016/j.nima.2024.170194" title="DOI" target="_blank">10.1016/j.nima.2024.170194</a> (publication) <tr><td class="formatRecordLabel"> Subject category </td><td style="padding-left:5px;">Detectors and Experimental Techniques</td></tr> <tr><td class="formatRecordLabel"> Accelerator/Facility, Experiment </td><td style="padding-left:5px;"><a href="https://cds.cern.ch/search?p=CERN%20ALPHA&f=693__a">CERN ALPHA</a></td></tr> <tr><td class="formatRecordLabel"> Abstract </td><td style="padding-left:5px;">This paper describes the ALPHA-2 apparatus, used at the CERN Antiproton Decelerator facility for the study of trapped antihydrogen atoms. Details of both the construction and performance are included. Prominence is given to both the new and the improved features, with respect to the original ALPHA assembly, of the apparatus including a stand-alone antiproton catching trap, the traps used to mix antiparticles to produce the anti-atoms, the magnetic atom trap used to hold some of them, and access for laser light to facilitate excitation of the antihydrogen 1S-2P and 1S-2S transitions.</td></tr> <tr><td class="formatRecordLabel"> Copyright/License </td><td style="padding-left:5px;">publication: © 2025 The Authors (License: <a href="http://creativecommons.org/licenses/by/4.0/">CC BY 4.0</a>)</td></tr> </table> <br/>Corresponding record in: <a href="http://inspirehep.net/record/2871447">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 2025-02-18, last modified 2025-02-18</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%3A2924599&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/2924599/files/Publication.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=2924599">Add to personal basket</a></li> <li>Export as <a style="text-decoration:underline;font-weight:normal" href="/record/2924599/export/hx?ln=en">BibTeX</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2924599/export/hm?ln=en">MARC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2924599/export/xm?ln=en">MARCXML</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2924599/export/xd?ln=en">DC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2924599/export/xe?ln=en">EndNote</a>,  <a style="text-decoration:underline;font-weight:normal" href="/record/2924599/export/xn?ln=en">NLM</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2924599/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:2924599/add'); $('#bookmark_sciencewise').bookmark({sites: ['sciencewise']}); $('#bookmark').bookmark({ sites: ['facebook', 'twitter', 'linkedin', 'google_plusone'], icons: '/img/bookmarks.png', url: 'https://cds.cern.ch/record/2924599', addEmail: true, title: "The ALPHA-2 apparatus - facilitating experimentation with trapped antihydrogen", description: "This paper describes the ALPHA-2 apparatus, used at the CERN Antiproton Decelerator facility for the study of trapped antihydrogen atoms. 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