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The possible attempts to resolve the anomaly rely on either (i) cooling the hydrogen gas via new dark matter-hydrogen interactions or (ii) modifying the soft photon background beyond the standard CMB one, as possibly suggested also by the ARCADE 2 excess. We argue that solutions belonging to the first class are generally in tension with cosmological dark matter probes once simple dark sector models are considered. Therefore, we propose soft photon emission by light dark matter as a natural solution to the 21 cm anomaly, studying a few realizations of this scenario. We find that the signal singles out a photophilic dark matter candidate characterised by an enhanced collective decay mechanism, such as axion mini-clusters. The recently claimed anomaly in the measurement of the 21 cm hydrogen absorption signal by EDGES at $z\sim 17$, if cosmological, requires the existence of new physics. The possible attempts to resolve the anomaly rely on either (i) cooling the hydrogen gas via new dark matter-hydrogen interactions or (ii) modifying the soft photon background beyond the standard CMB one, as possibly suggested also by the ARCADE~2 excess. We argue that solutions belonging to the first class are generally in tension with cosmological dark matter probes once simple dark sector models are considered. Therefore, we propose soft photon emission by light dark matter as a natural solution to the 21 cm anomaly, studying a few realizations of this scenario. We find that the signal singles out a photophilic dark matter candidate characterised by an enhanced collective decay mechanism, such as axion mini-clusters. Fraser, Sean; Hektor, Andi; Hütsi, Gert; Kannike, Kristjan; Marzo, Carlo; Marzola, Luca; Spethmann, Christian; Racioppi, Antonio; Raidal, Martti; Vaskonen, Ville; Veermäe, Hardi" /> <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 : The EDGES 21 cm Anomaly and Properties of Dark Matter" name="citation_title" /> <meta content="Fraser, Sean" name="citation_author" /> <meta content="Veermäe, Hardi" name="citation_author" /> <meta content="Racioppi, Antonio" name="citation_author" /> <meta content="Hektor, Andi" name="citation_author" /> <meta content="Kannike, Kristjan" name="citation_author" /> <meta content="Vaskonen, Ville" name="citation_author" /> <meta content="Hütsi, Gert" name="citation_author" /> <meta content="Marzola, Luca" name="citation_author" /> <meta content="Raidal, Martti" name="citation_author" /> <meta content="Spethmann, Christian" name="citation_author" /> <meta content="Marzo, Carlo" name="citation_author" /> <meta content="10.1016/j.physletb.2018.08.035" name="citation_doi" /> <meta content="Phys. 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The possible attempts to resolve the anomaly rely on either (i) cooling the hydrogen gas via new dark matter-hydrogen interactions or (ii) modifying the soft photon background beyond the standard CMB one, as possibly suggested also by the ARCADE 2 excess. We argue that solutions belonging to the first class are generally in tension with cosmological dark matter probes once simple dark sector models are considered. Therefore, we propose soft photon emission by light dark matter as a natural solution to the 21 cm anomaly, studying a few realizations of this scenario. We find that the signal singles out a photophilic dark matter candidate characterised by an enhanced collective decay mechanism, such as axion mini-clusters." property="og:description" /> <meta content="arXiv" property="og:description" /> <meta content="The recently claimed anomaly in the measurement of the 21 cm hydrogen absorption signal by EDGES at $z\sim 17$, if cosmological, requires the existence of new physics. The possible attempts to resolve the anomaly rely on either (i) cooling the hydrogen gas via new dark matter-hydrogen interactions or (ii) modifying the soft photon background beyond the standard CMB one, as possibly suggested also by the ARCADE~2 excess. We argue that solutions belonging to the first class are generally in tension with cosmological dark matter probes once simple dark sector models are considered. Therefore, we propose soft photon emission by light dark matter as a natural solution to the 21 cm anomaly, studying a few realizations of this scenario. 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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"> Report number </td><td style="padding-left:5px;"><a href="http://arxiv.org/abs/arXiv:1803.03245">arXiv:1803.03245</a> ; CERN-TH-2018-053</td></tr> <tr><td class="formatRecordLabel"> Title </td><td style="padding-left:5px;"><b>The EDGES 21 cm Anomaly and Properties of Dark Matter</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 = "დამალვა" } else { more.style.display = 'none'; extension.style.display = ''; link.innerHTML = "ყველა 11 ავტორის ჩვენება " } 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=Fraser%2C%20Sean&ln=ka">Fraser, Sean</a> (NICPB, Tallinn) ; <a href="https://cds.cern.ch/search?f=author&p=Hektor%2C%20Andi&ln=ka">Hektor, Andi</a> (NICPB, Tallinn) ; <a href="https://cds.cern.ch/search?f=author&p=H%C3%BCtsi%2C%20Gert&ln=ka">Hütsi, Gert</a> (NICPB, Tallinn) ; <a href="https://cds.cern.ch/search?f=author&p=Kannike%2C%20Kristjan&ln=ka">Kannike, Kristjan</a> (NICPB, Tallinn) ; <a href="https://cds.cern.ch/search?f=author&p=Marzo%2C%20Carlo&ln=ka">Marzo, Carlo</a> (NICPB, Tallinn) ; <a href="https://cds.cern.ch/search?f=author&p=Marzola%2C%20Luca&ln=ka">Marzola, Luca</a> (NICPB, Tallinn) ; <a href="https://cds.cern.ch/search?f=author&p=Spethmann%2C%20Christian&ln=ka">Spethmann, Christian</a> (NICPB, Tallinn) ; <a href="https://cds.cern.ch/search?f=author&p=Racioppi%2C%20Antonio&ln=ka">Racioppi, Antonio</a> (NICPB, Tallinn) ; <a href="https://cds.cern.ch/search?f=author&p=Raidal%2C%20Martti&ln=ka">Raidal, Martti</a> (CERN ; NICPB, Tallinn) ; <a href="https://cds.cern.ch/search?f=author&p=Vaskonen%2C%20Ville&ln=ka">Vaskonen, Ville</a> (NICPB, Tallinn)<span id="more" style=""> ; <a href="https://cds.cern.ch/search?f=author&p=Veerm%C3%A4e%2C%20Hardi&ln=ka">Veermäe, Hardi</a> (CERN ; NICPB, Tallinn)</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;">2018-10-10</td></tr> <tr><td class="formatRecordLabel"> Imprint </td><td style="padding-left:5px;">2018-03-08</td></tr> <tr><td class="formatRecordLabel"> Number of pages </td><td style="padding-left:5px;">6</td></tr> <tr><td class="formatRecordLabel"> Note </td><td style="padding-left:5px;">7 pages, 2 figures</td></tr> <tr><td class="formatRecordLabel"> In: </td><td style="padding-left:5px;"><a href="http://dx.doi.org/10.1016/j.physletb.2018.08.035"><i>Phys. Lett. B</i> 785 (2018) 159-164</a> </a></td></tr> <tr><td class="formatRecordLabel"> DOI </td><td style="padding-left:5px;"><a href="http://dx.doi.org/10.1016/j.physletb.2018.08.035" title="DOI" target="_blank">10.1016/j.physletb.2018.08.035</a> (publication) <tr><td class="formatRecordLabel"> Subject category </td><td style="padding-left:5px;">astro-ph.HE ; Astrophysics and Astronomy ; hep-ph ; Particle Physics - Phenomenology</td></tr> <tr><td class="formatRecordLabel"> Abstract </td><td style="padding-left:5px;">The recently claimed anomaly in the measurement of the 21 cm hydrogen absorption signal by EDGES at $z\sim 17$, if cosmological, requires the existence of new physics. The possible attempts to resolve the anomaly rely on either (i) cooling the hydrogen gas via new dark matter-hydrogen interactions or (ii) modifying the soft photon background beyond the standard CMB one, as possibly suggested also by the ARCADE 2 excess. We argue that solutions belonging to the first class are generally in tension with cosmological dark matter probes once simple dark sector models are considered. Therefore, we propose soft photon emission by light dark matter as a natural solution to the 21 cm anomaly, studying a few realizations of this scenario. We find that the signal singles out a photophilic dark matter candidate characterised by an enhanced collective decay mechanism, such as axion mini-clusters.</td></tr> <tr><td class="formatRecordLabel"> Copyright/License </td><td style="padding-left:5px;">preprint: (License: <a href="http://arxiv.org/licenses/nonexclusive-distrib/1.0/">arXiv nonexclusive-distrib 1.0</a>)<br/>The Author(s)</td></tr> </table> <br /><div style="max-width:1024px;margin:auto"><div style="overflow-x:auto;display:inline;width:100%;"><a href="/record/2308095/plots#0"><img style="vertical-align:middle;" src="https://cds.cern.ch/record/2308095/files/photosphere_z17.png" title=" Photosphere of the Universe (\ie, optical depth $\tau=1$) for a broad range of physical photon energies. The observer is assumed to be located at redshift $z=17$. In the lowest energy section of the plot, before the first small plateau, the energy losses are dominated by photoionizations. Beyond that, up to the beginning of the large plateau, the Compton losses are dominating. At the large flat plateau region the energy loss is dominated by the pair production on matter. On the final falling part of the curves the energy losses are determined by photon-photon pair production. The calculations use results presented in~\cite{1989ApJ...344..551Z}." width="200px"/></a> <a href="/record/2308095/plots#1"><img style="vertical-align:middle;" src="https://cds.cern.ch/record/2308095/files/mLambda.png" title=" The solid lines show the parameter values which produce the required photon excess assuming that all DM consists of $X$. The blue, red and green lines correspond to the case $X \to \gamma \tilde X$, with the labels showing the redshifts when the photons were emitted. The gray lines correspond instead to $X \to \gamma \gamma$. The mass bounds arise from Eq.~\eqref{range:Eg}, as described in the text. The region on the left of the vertical dashed line is excluded for fermionic DM by the Tremaine-Gunn bound. The area below the horizontal dashed line is excluded by the electroweak precision measurements in the case of exiting DM. In the region on the right of the dotted curve the lifetime of $X$ is shorter than the age of the Universe for the $X \to \gamma \gamma$ case." width="200px"/></a> </div></div><br /> <br/>Corresponding record in: <a href="http://inspirehep.net/record/1659140">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"> ჩანაწერი შექმნილია 2018-03-12, ბოლოს შესწორებულია 2023-05-10</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=ka&p=recid%3A2308095&rm=wrd" class="moreinfo">მსგავსი ჩანაწერები</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">Article from SCOAP3:</small> <br /><a href="/record/2308095/files/scoap3-fulltext.pdf"><img style="border:none" src="/img/file-icon-text-12x16.gif" alt="სრული ტექსტის ჩამოტვირთვა"/>PDF</a><br /></div><div><small class="detailedRecordActions">სრული ტექსტი:</small> <br /><a href="/record/2308095/files/1803.03245.pdf"><img style="border:none" src="/img/file-icon-text-12x16.gif" alt="სრული ტექსტის ჩამოტვირთვა"/>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=ka&recid=2308095">პირად კალათაში დამატება</a></li> <li>ექსპორტირება <a style="text-decoration:underline;font-weight:normal" href="/record/2308095/export/hx?ln=ka">BibTeX</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2308095/export/hm?ln=ka">MARC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2308095/export/xm?ln=ka">MARCXML</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2308095/export/xd?ln=ka">DC</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2308095/export/xe?ln=ka">EndNote</a>,  <a style="text-decoration:underline;font-weight:normal" href="/record/2308095/export/xn?ln=ka">NLM</a>, <a style="text-decoration:underline;font-weight:normal" href="/record/2308095/export/xw?ln=ka">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/1803.0324/add'); $('#bookmark_sciencewise').bookmark({sites: ['sciencewise']}); $('#bookmark').bookmark({ sites: ['facebook', 'twitter', 'linkedin', 'google_plusone'], icons: '/img/bookmarks.png', url: 'https://cds.cern.ch/record/2308095', addEmail: true, title: "The EDGES 21 cm Anomaly and Properties of Dark Matter", description: "The recently claimed anomaly in the measurement of the 21 cm hydrogen absorption signal by EDGES at z\u223c17 , if cosmological, requires the existence of new physics. The possible attempts to resolve the anomaly rely on either (i) cooling the hydrogen gas via new dark matter-hydrogen interactions or (ii) modifying the soft photon background beyond the standard CMB one, as possibly suggested also by the ARCADE 2 excess. We argue that solutions belonging to the first class are generally in tension with cosmological dark matter probes once simple dark sector models are considered. Therefore, we propose soft photon emission by light dark matter as a natural solution to the 21 cm anomaly, studying a few realizations of this scenario. 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