A search is reported for near-threshold structures in the <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mi>J</a:mi><a:mo>/</a:mo><a:mi>ψ</a:mi><a:mi>J</a:mi><a:mo>/</a:mo><a:mi>ψ</a:mi></a:mrow></a:math> invariant mass spectrum produced in proton-proton collisions at <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mrow><c:msqrt><c:mrow><c:mi>s</c:mi></c:mrow></c:msqrt><c:mo>=</c:mo><c:mn>13</c:mn><c:mtext> </c:mtext><c:mtext> </c:mtext><c:mi>TeV</c:mi></c:mrow></c:math> from data collected by the CMS experiment, corresponding to an integrated luminosity of <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:mrow><e:mn>135</e:mn><e:mtext> </e:mtext><e:mtext> </e:mtext><e:msup><e:mrow><e:mi>fb</e:mi></e:mrow><e:mrow><e:mo>−</e:mo><e:mn>1</e:mn></e:mrow></e:msup></e:mrow></e:math>. Three structures are found, and a model with quantum interference among these structures provides a good description of the data. A new structure is observed with a local significance above 5 standard deviations at a mass of <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"><g:mrow><g:msubsup><g:mrow><g:mn>6638</g:mn></g:mrow><g:mrow><g:mo>−</g:mo><g:mn>38</g:mn></g:mrow><g:mrow><g:mo>+</g:mo><g:mn>43</g:mn></g:mrow></g:msubsup><g:msubsup><g:mrow><g:mo stretchy="false">(</g:mo><g:mi>stat</g:mi><g:mo stretchy="false">)</g:mo></g:mrow><g:mrow><g:mo>−</g:mo><g:mn>31</g:mn></g:mrow><g:mrow><g:mo>+</g:mo><g:mn>16</g:mn></g:mrow></g:msubsup><g:mo stretchy="false">(</g:mo><g:mi>syst</g:mi><g:mo stretchy="false">)</g:mo><g:mtext> </g:mtext><g:mtext> </g:mtext><g:mi>MeV</g:mi></g:mrow></g:math>. Another structure with even higher significance is found at a mass of <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"><m:mrow><m:msubsup><m:mrow><m:mn>6847</m:mn></m:mrow><m:mrow><m:mo>−</m:mo><m:mn>28</m:mn></m:mrow><m:mrow><m:mo>+</m:mo><m:mn>44</m:mn></m:mrow></m:msubsup><m:msubsup><m:mrow><m:mo stretchy="false">(</m:mo><m:mi>stat</m:mi><m:mo stretchy="false">)</m:mo></m:mrow><m:mrow><m:mo>−</m:mo><m:mn>20</m:mn></m:mrow><m:mrow><m:mo>+</m:mo><m:mn>48</m:mn></m:mrow></m:msubsup><m:mo stretchy="false">(</m:mo><m:mi>syst</m:mi><m:mo stretchy="false">)</m:mo><m:mtext> </m:mtext><m:mtext> </m:mtext><m:mi>MeV</m:mi></m:mrow></m:math>, which is consistent with the <s:math xmlns:s="http://www.w3.org/1998/Math/MathML" display="inline"><s:mrow><s:mi>X</s:mi><s:mo stretchy="false">(</s:mo><s:mn>6900</s:mn><s:mo stretchy="false">)</s:mo></s:mrow></s:math> resonance reported by the LHCb experiment and confirmed by the ATLAS experiment. Evidence for another new structure, with a local significance of 4.7 standard deviations, is found at a mass of <w:math xmlns:w="http://www.w3.org/1998/Math/MathML" display="inline"><w:mrow><w:msubsup><w:mrow><w:mn>7134</w:mn></w:mrow><w:mrow><w:mo>−</w:mo><w:mn>25</w:mn></w:mrow><w:mrow><w:mo>+</w:mo><w:mn>48</w:mn></w:mrow></w:msubsup><w:msubsup><w:mrow><w:mo stretchy="false">(</w:mo><w:mi>stat</w:mi><w:mo stretchy="false">)</w:mo></w:mrow><w:mrow><w:mo>−</w:mo><w:mn>15</w:mn></w:mrow><w:mrow><w:mo>+</w:mo><w:mn>41</w:mn></w:mrow></w:msubsup><w:mo stretchy="false">(</w:mo><w:mi>syst</w:mi><w:mo stretchy="false">)</w:mo><w:mtext> </w:mtext><w:mtext> </w:mtext><w:mi>MeV</w:mi></w:mrow></w:math>. Results are also reported for a model without interference, which does not fit the data as well and shows mass shifts up to 150 MeV relative to the model with interference. © 2024 CERN, for the CMS Collaboration 2024 CERN