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Observation of the ϒ(3S) Meson and Suppression of ϒ States in Pb-Pb Collisions at sNN=5.02 TeV

https://doi.org/10.1103/PhysRevLett.133.022302

Tumasyan, A ; Adam, W ; Andrejkovic, J W ; Bergauer, T ; Chatterjee, S ; Damanakis, K ; Dragicevic, M ; Escalante_Del_Valle, A ; Hussain, P S ; Jeitler, M ; et al ( July 2024 , Physical Review Letters)

The production of $ϒ (2 S)$ and $ϒ (3 S)$ mesons in lead-lead (Pb-Pb) and proton-proton ( $p p$ ) collisions is studied in their dimuon decay channel using the CMS detector at the LHC. The $ϒ (3 S)$ meson is observed for the first time in Pb-Pb collisions, with a significance above 5 standard deviations. The ratios of yields measured in Pb-Pb and $p p$ collisions are reported for both the $ϒ (2 S)$ and $ϒ (3 S)$ mesons, as functions of transverse momentum and Pb-Pb collision centrality. These ratios, when appropriately scaled, are significantly less than unity, indicating a suppression of $ϒ$ yields in Pb-Pb collisions. This suppression increases from peripheral to central Pb-Pb collisions. Furthermore, the suppression is stronger for $ϒ (3 S)$ mesons compared to $ϒ (2 S)$ mesons, extending the pattern of sequential suppression of quarkonium states in nuclear collisions previously seen for the $J / ψ$ , $ψ (2 S)$ , $ϒ (1 S)$ , and $ϒ (2 S)$ mesons.

<supplementary-material><permissions><copyright-statement>© 2024 CERN, for the CMS Collaboration</copyright-statement><copyright-year>2024</copyright-year><copyright-holder>CERN</copyright-holder></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> Free, publicly-accessible full text available July 1, 2025</span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10549903-search-high-mass-exclusive-diphoton-production-tagged-protons-proton-proton-collisions" itemprop="url"> <span class='span-link' itemprop="name">Search for high-mass exclusive diphoton production with tagged protons in proton-proton collisions at s=13 TeV</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevD.110.012010" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevD.110.012010 <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Tumasyan, A</span> <span class="sep">; </span><span class="author" itemprop="author">Adam, W</span> <span class="sep">; </span><span class="author" itemprop="author">Andrejkovic, J W</span> <span class="sep">; </span><span class="author" itemprop="author">Bergauer, T</span> <span class="sep">; </span><span class="author" itemprop="author">Chatterjee, S</span> <span class="sep">; </span><span class="author" itemprop="author">Damanakis, K</span> <span class="sep">; </span><span class="author" itemprop="author">Dragicevic, M</span> <span class="sep">; </span><span class="author" itemprop="author">Escalante_Del_Valle, A</span> <span class="sep">; </span><span class="author" itemprop="author">Hussain, P S</span> <span class="sep">; </span><span class="author" itemprop="author">Jeitler, M</span> <span class="sep">; </span><span class="author">et al</span></span> <span class="year">( <time itemprop="datePublished" datetime="2024-07-01">July 2024</time> , Physical Review D) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <p>A search is presented for high-mass exclusive diphoton production via photon-photon fusion in proton-proton collisions at<math display='inline'><msqrt><mi>s</mi></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math>in events where both protons survive the interaction. The analysis utilizes data corresponding to an integrated luminosity of<math display='inline'><mn>103</mn><mtext> </mtext><mtext> </mtext><msup><mi>fb</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>collected in 2016–2018 with the central CMS detector and the CMS and TOTEM precision proton spectrometer (PPS). Events that have two photons with high transverse momenta (<math display='inline'><mrow><msubsup><mrow><mi>p</mi></mrow><mrow><mi mathvariant='normal'>T</mi></mrow><mrow><mi>γ</mi></mrow></msubsup></mrow><mo>></mo><mn>100</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>), back-to-back in azimuth, and with a large diphoton invariant mass (<math display='inline'><msub><mi>m</mi><mrow><mi>γ</mi><mi>γ</mi></mrow></msub><mo>></mo><mn>350</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>) are selected. To remove the dominant inclusive diphoton backgrounds, the kinematic properties of the protons detected in PPS are required to match those of the central diphoton system. Only events having opposite-side forward protons detected with a fractional momentum loss between 0.035 and 0.15 (0.18) for the detectors on the negative (positive) side of CMS are considered. One exclusive diphoton candidate is observed for an expected background of 1.1 events. Limits at 95% confidence level are derived for the four-photon anomalous coupling parameters<math display='inline'><mrow><mo stretchy='false'>|</mo><msub><mi>ζ</mi><mn>1</mn></msub><mo stretchy='false'>|</mo></mrow><mo><</mo><mn>0.073</mn><mtext> </mtext><mtext> </mtext><msup><mi>TeV</mi><mrow><mo>−</mo><mn>4</mn></mrow></msup></math>and<math display='inline'><mrow><mo stretchy='false'>|</mo><msub><mi>ζ</mi><mn>2</mn></msub><mo stretchy='false'>|</mo></mrow><mo><</mo><mn>0.15</mn><mtext> </mtext><mtext> </mtext><msup><mi>TeV</mi><mrow><mo>−</mo><mn>4</mn></mrow></msup></math>, using an effective field theory. Additionally, upper limits are placed on the production of axionlike particles with coupling strength to photons<math display='inline'><msup><mi>f</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>that varies from<math display='inline'><mn>0.03</mn><mtext> </mtext><mtext> </mtext><msup><mi>TeV</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>to<math display='inline'><mn>1</mn><mtext> </mtext><mtext> </mtext><msup><mi>TeV</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>over the mass range from 500 to 2000 GeV.</p> <sec><title/><supplementary-material><permissions><copyright-statement>© 2024 CERN, for the CMS and TOTEMs Collaboration</copyright-statement><copyright-year>2024</copyright-year><copyright-holder>CERN</copyright-holder></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> <div class="actions" style="padding-left:10px;"> <span class="reader-count"> Free, publicly-accessible full text available July 1, 2025</span> </div> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10549901-search-central-exclusive-production-top-quark-pairs-proton-proton-collisions-sqrt-tev-tagged-protons" itemprop="url"> <span class='span-link' itemprop="name">Search for central exclusive production of top quark pairs in proton-proton collisions at $$ \sqrt{s} $$ = 13 TeV with tagged protons</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1007/JHEP06(2024)187" target="_blank" title="Link to document DOI">https://doi.org/10.1007/JHEP06(2024)187 <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Tumasyan, A</span> <span class="sep">; </span><span class="author" itemprop="author">Adam, W</span> <span class="sep">; </span><span class="author" itemprop="author">Andrejkovic, J W</span> <span class="sep">; </span><span class="author" itemprop="author">Bergauer, T</span> <span class="sep">; </span><span class="author" itemprop="author">Chatterjee, S</span> <span class="sep">; </span><span class="author" itemprop="author">Damanakis, K</span> <span class="sep">; </span><span class="author" itemprop="author">Dragicevic, M</span> <span class="sep">; </span><span class="author" itemprop="author">Escalante_Del_Valle, A</span> <span class="sep">; </span><span class="author" itemprop="author">Hussain, P S</span> <span class="sep">; </span><span class="author" itemprop="author">Jeitler, M</span> <span class="sep">; </span><span class="author">et al</span></span> <span class="year">( <time itemprop="datePublished" datetime="2024-06-01">June 2024</time> , Journal of High Energy Physics) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <title>A<sc>bstract</sc>

A search for the central exclusive production of top quark-antiquark pairs ($$ \textrm{t}\overline{\textrm{t}} $$ $t \bar{t}$ ) is performed for the first time using proton-tagged events in proton-proton collisions at the LHC at a centre-of-mass energy of 13 TeV. The data correspond to an integrated luminosity of 29.4 fb⁻¹. The$$ \textrm{t}\overline{\textrm{t}} $$ $t \bar{t}$ decay products are reconstructed using the central CMS detector, while forward protons are measured in the CMS-TOTEM precision proton spectrometer. An observed (expected) upper bound on the production cross section of 0.59 (1.14) pb is set at 95% confidence level, for collisions of protons with fractional momentum losses between 2 and 20%.

Free, publicly-accessible full text available June 1, 2025