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A prominent way to introduce this baseline is through measurements in pp collisions. However, it is known that the binding effects of the proton in a heavy nucleus can modify said baseline without the creation of a quark-gluon plasma. In order to study such cold nuclear matter effects one can study collisions with a smaller transverse size and density, such as proton-lead (p-Pb) collisions. This thesis presents the analysis of dielectron production in p-Pb collisions at a collision energy in the centre of mass system of $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV as a function of the invariant mass and the momentum of the e+e- pair. The main purpose of the analysis is to study modifications with respect to scaling expectations of the contribution of heavy-flavour production and their impact on the measured dielectron yield. This is done by measuring the dielectron yield in p-Pb collisions and comparing it to baseline expectations. The baseline for light flavour hadron decays is constructed based on measurements in \ppb collisions at $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV. The heavy-flavour contribution uses the measured production cross sections of heavy quarks in pp collisions and assumes a scaling of the production cross section with the number of binary nucleon-nucleon collisions. It is found that the baseline constructed in this way is able to describe the data within the experimental uncertainties. To investigate the impact of a possible modification of the contribution of the charm hadron decays to the dielectron spectrum, model calculations based on globally available data are included in the charm baseline. This reduces the expected contribution and a tension starts to arise in the mass region dominated by the heavy-flavour contributions. The possibility of an additional source of dielectrons produced as thermal radiation from a hot and dense medium formed in p-Pb collisions is investigated by also including such a source in the comparisons. The conclusion drawn from the presented measurement and its comparisons to baseline calculations under different assumptions is that no significant suppression of the charm contribution due to cold nuclear matter effects is present in the dielectron spectrum. However, it is possible that the suppression could be present but is offset due to the presence of a thermal source of dileptons, keeping the overall dilepton rate constant. The discussion finishes with an outlook on future measurements that might be able to resolve this ambiguity. Scheid, Horst Sebastian" /> <meta name="keywords" content="CERN Document Server, WebSearch, ALICE Preprints" /> <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="On charm and beauty in dielectron measurements - Dielectron production in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV with ALICE" name="citation_title" /> <meta content="Scheid, Horst Sebastian" name="citation_author" /> <meta content="2024/11/08" name="citation_publication_date" /> <meta name="citation_online_date" content="2024/11/26"> <meta content="CERN-THESIS-2024-238" name="citation_technical_report_number" /> <meta content="CERN" name="citation_dissertation_institution" /> <meta name="citation_pdf_url" content="https://cds.cern.ch/record/2918062/files/CERN-THESIS-2024-238.pdf" />  <meta content="On charm and beauty in dielectron measurements - Dielectron production in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV with ALICE" property="og:title" /> <meta content="website" property="og:type" /> <meta content="https://cds.cern.ch/record/2918062" property="og:url" /> <meta content="CERN Document Server" property="og:site_name" /> <meta content="One possibility to study the quark-gluon plasma created in ultra-relativistic heavy-ion collisions is to measure modifications of an established baseline and by this infer on the interaction of a given probe with the created medium. A prominent way to introduce this baseline is through measurements in pp collisions. However, it is known that the binding effects of the proton in a heavy nucleus can modify said baseline without the creation of a quark-gluon plasma. In order to study such cold nuclear matter effects one can study collisions with a smaller transverse size and density, such as proton-lead (p-Pb) collisions. This thesis presents the analysis of dielectron production in p-Pb collisions at a collision energy in the centre of mass system of $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV as a function of the invariant mass and the momentum of the e+e- pair. The main purpose of the analysis is to study modifications with respect to scaling expectations of the contribution of heavy-flavour production and their impact on the measured dielectron yield. This is done by measuring the dielectron yield in p-Pb collisions and comparing it to baseline expectations. The baseline for light flavour hadron decays is constructed based on measurements in \ppb collisions at $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV. The heavy-flavour contribution uses the measured production cross sections of heavy quarks in pp collisions and assumes a scaling of the production cross section with the number of binary nucleon-nucleon collisions. It is found that the baseline constructed in this way is able to describe the data within the experimental uncertainties. To investigate the impact of a possible modification of the contribution of the charm hadron decays to the dielectron spectrum, model calculations based on globally available data are included in the charm baseline. This reduces the expected contribution and a tension starts to arise in the mass region dominated by the heavy-flavour contributions. The possibility of an additional source of dielectrons produced as thermal radiation from a hot and dense medium formed in p-Pb collisions is investigated by also including such a source in the comparisons. The conclusion drawn from the presented measurement and its comparisons to baseline calculations under different assumptions is that no significant suppression of the charm contribution due to cold nuclear matter effects is present in the dielectron spectrum. However, it is possible that the suppression could be present but is offset due to the presence of a thermal source of dileptons, keeping the overall dilepton rate constant. The discussion finishes with an outlook on future measurements that might be able to resolve this ambiguity." property="og:description" />  <meta content="summary" name="twitter:card" /> <style></style> </head> <body class="ALICE32Preprints search" lang="en">  <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=en&referer=https%3A//cds.cern.ch/record/2918062" 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=en">Search</a></li> <li class="menu-444 "><a class="" title="" href="https://cds.cern.ch/submit?ln=en">Submit</a></li> <li class="menu-426 "><a class="" href="https://cds.cern.ch/help/?ln=en">Help</a></li> <li class="leaf hassubcdsmenu"> <a hreflang="en" class="header" href="https://cds.cern.ch/youraccount/display?ln=en">Personalize</a> <ul class="subsubcdsmenu"><li><a href="https://cds.cern.ch/youralerts/list?ln=en">Your alerts</a></li><li><a href="https://cds.cern.ch/yourbaskets/display?ln=en">Your baskets</a></li><li><a href="https://cds.cern.ch/yourcomments?ln=en">Your comments</a></li><li><a href="https://cds.cern.ch/youralerts/display?ln=en">Your searches</a></li></ul></li> </ul> </div> </div> </div>  <table class="navtrailbox"> <tr> <td class="navtrailboxbody"> <a href="/?ln=en" class="navtrail">Home</a> > <a href="/collection/CERN%20Experiments?ln=en" class="navtrail">CERN Experiments</a> > <a href="/collection/LHC%20Experiments?ln=en" class="navtrail">LHC Experiments</a> > <a href="/collection/ALICE?ln=en" class="navtrail">ALICE</a> > <a href="/collection/ALICE%20Preprints?ln=en" class="navtrail">ALICE Preprints</a> > On charm and beauty in dielectron measurements - Dielectron production in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV with ALICE </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/2918062/?ln=en">Information </a></li><li class=""><a href="/record/2918062/comments?ln=en">Discussion (0) </a></li><li class=""><a href="/record/2918062/files?ln=en">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="2918062"></abbr> <style type="text/css">  </style> <script type="text/javascript" src="/js/pdf-previewer-append-to-table.js"></script> <table class="formatRecordTableFullWidth" > <tr> <td class="formatRecordHeader" style="background-image: url('https://cds.cern.ch/img/journals.jpg');" colspan="2"> Thesis </td> </tr> <tr><td class="formatRecordLabel"> Report number </td><td style="padding-left:5px;">CERN-THESIS-2024-238</td></tr> <tr><td class="formatRecordLabel"> Title </td><td style="padding-left:5px;"><b>On charm and beauty in dielectron measurements - Dielectron production in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV with ALICE</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=Scheid%2C%20Horst%20Sebastian&ln=en">Scheid, Horst Sebastian</a> (CERN)</td></tr> <tr><td class="formatRecordLabel"> Publication </td><td style="padding-left:5px;">2024 - 188.</td></tr> <tr><td class="formatRecordLabel"> Thesis note </td><td style="padding-left:5px;">PhD : Goethe U., Frankfurt (main) : 2024-07-11</td></tr> <tr><td class="formatRecordLabel"> Thesis supervisor(s) </td><td style="padding-left:5px;"><a href="/search?f=author&p=Appelshäuser, Harald">Appelshäuser, Harald</a></td></tr> <tr><td class="formatRecordLabel"> Note </td><td style="padding-left:5px;">Presented 08 Nov 2024</td></tr> <tr><td class="formatRecordLabel"> Subject category </td><td style="padding-left:5px;">Particle Physics - Experiment ; Nuclear Physics - Experiment</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> ; <a href="https://cds.cern.ch/search?p=ALICE&f=693__e">ALICE</a></td></tr> <tr><td class="formatRecordLabel"> Abstract </td><td style="padding-left:5px;">One possibility to study the quark-gluon plasma created in ultra-relativistic heavy-ion collisions is to measure modifications of an established baseline and by this infer on the interaction of a given probe with the created medium. A prominent way to introduce this baseline is through measurements in pp collisions. However, it is known that the binding effects of the proton in a heavy nucleus can modify said baseline without the creation of a quark-gluon plasma. In order to study such cold nuclear matter effects one can study collisions with a smaller transverse size and density, such as proton-lead (p-Pb) collisions. This thesis presents the analysis of dielectron production in p-Pb collisions at a collision energy in the centre of mass system of $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV as a function of the invariant mass and the momentum of the e+e- pair. The main purpose of the analysis is to study modifications with respect to scaling expectations of the contribution of heavy-flavour production and their impact on the measured dielectron yield. This is done by measuring the dielectron yield in p-Pb collisions and comparing it to baseline expectations. The baseline for light flavour hadron decays is constructed based on measurements in \ppb collisions at $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV. The heavy-flavour contribution uses the measured production cross sections of heavy quarks in pp collisions and assumes a scaling of the production cross section with the number of binary nucleon-nucleon collisions. It is found that the baseline constructed in this way is able to describe the data within the experimental uncertainties. To investigate the impact of a possible modification of the contribution of the charm hadron decays to the dielectron spectrum, model calculations based on globally available data are included in the charm baseline. This reduces the expected contribution and a tension starts to arise in the mass region dominated by the heavy-flavour contributions. The possibility of an additional source of dielectrons produced as thermal radiation from a hot and dense medium formed in p-Pb collisions is investigated by also including such a source in the comparisons. The conclusion drawn from the presented measurement and its comparisons to baseline calculations under different assumptions is that no significant suppression of the charm contribution due to cold nuclear matter effects is present in the dielectron spectrum. However, it is possible that the suppression could be present but is offset due to the presence of a thermal source of dileptons, keeping the overall dilepton rate constant. The discussion finishes with an outlook on future measurements that might be able to resolve this ambiguity.</td></tr> </table> <br/>Email contact: <a href="mailto:s.scheid@cern.ch">s.scheid@cern.ch</a> <small> </small> <small> </small> <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 2024-11-26, last modified 2024-12-05</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%3A2918062&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/2918062/files/CERN-THESIS-2024-238.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=2918062">Add to personal basket</a></li> <li>Export as <a style="text-decoration:underline;font-weight:normal" href="/record/2918062/export/hx?ln=en">BibTeX</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2918062/export/hm?ln=en">MARC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2918062/export/xm?ln=en">MARCXML</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2918062/export/xd?ln=en">DC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2918062/export/xe?ln=en">EndNote</a>,  <a style="text-decoration:underline;font-weight:normal" href="/record/2918062/export/xn?ln=en">NLM</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2918062/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:2918062/add'); $('#bookmark_sciencewise').bookmark({sites: ['sciencewise']}); $('#bookmark').bookmark({ sites: ['facebook', 'twitter', 'linkedin', 'google_plusone'], icons: '/img/bookmarks.png', url: 'https://cds.cern.ch/record/2918062', addEmail: true, title: "On charm and beauty in dielectron measurements - Dielectron production in p-Pb collisions at $\\sqrt{s_{\\mathrm{NN}}} = 5.02$ TeV with ALICE", description: "One possibility to study the quark-gluon plasma created in ultra-relativistic heavy-ion collisions is to measure modifications of an established baseline and by this infer on the interaction of a given probe with the created medium. A prominent way to introduce this baseline is through measurements in pp collisions. However, it is known that the binding effects of the proton in a heavy nucleus can modify said baseline without the creation of a quark-gluon plasma. In order to study such cold nuclear matter effects one can study collisions with a smaller transverse size and density, such as proton-lead (p-Pb) collisions. This thesis presents the analysis of dielectron production in p-Pb collisions at a collision energy in the centre of mass system of $\\sqrt{s_{\\mathrm{NN}}} = 5.02$ TeV as a function of the invariant mass and the momentum of the e+e- pair. The main purpose of the analysis is to study modifications with respect to scaling expectations of the contribution of heavy-flavour production and their impact on the measured dielectron yield. This is done by measuring the dielectron yield in p-Pb collisions and comparing it to baseline expectations. The baseline for light flavour hadron decays is constructed based on measurements in \\ppb collisions at $\\sqrt{s_{\\mathrm{NN}}} = 5.02$ TeV. The heavy-flavour contribution uses the measured production cross sections of heavy quarks in pp collisions and assumes a scaling of the production cross section with the number of binary nucleon-nucleon collisions. It is found that the baseline constructed in this way is able to describe the data within the experimental uncertainties. To investigate the impact of a possible modification of the contribution of the charm hadron decays to the dielectron spectrum, model calculations based on globally available data are included in the charm baseline. This reduces the expected contribution and a tension starts to arise in the mass region dominated by the heavy-flavour contributions. The possibility of an additional source of dielectrons produced as thermal radiation from a hot and dense medium formed in p-Pb collisions is investigated by also including such a source in the comparisons. The conclusion drawn from the presented measurement and its comparisons to baseline calculations under different assumptions is that no significant suppression of the charm contribution due to cold nuclear matter effects is present in the dielectron spectrum. However, it is possible that the suppression could be present but is offset due to the presence of a thermal source of dileptons, keeping the overall dilepton rate constant. 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