The first search for soft unclustered energy patterns (SUEPs) is performed using an integrated luminosity of <math><mrow><mn>138</mn><mtext> </mtext><mtext> </mtext><msup><mrow><mi>fb</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math> of proton-proton collision data at <math><mrow><msqrt><mrow><mi>s</mi></mrow></msqrt><mo>=</mo><mn>13</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></mrow></math>, collected in 2016–2018 by the CMS detector at the LHC. Such SUEPs are predicted by hidden valley models with a new, confining force with a large ’t Hooft coupling. In events with boosted topologies, selected by high-threshold hadronic triggers, the multiplicity and sphericity of clustered tracks are used to reject the background from standard model quantum chromodynamics. With no observed excess of events over the standard model expectation, limits are set on the cross section for production via gluon fusion of a scalar mediator with SUEP-like decays.

Armenia

Austria

Belgium

Brazil

Search for Soft Unclustered Energy Patterns in Proton-Proton Collisions at 13 TeV

We propose the gauge theory bootstrap, a method to compute the pion <math><mi>S</mi></math> matrix that describes the low-energy physics of the strong interaction and other similar gauge theories. The phase shifts of the <math><mi>S</mi><mn>0</mn></math>, <math><mi>P</mi><mn>1</mn></math>, and <math><mi>S</mi><mn>2</mn></math> waves obtained are in good agreement with experimental results. The only numerical inputs are the quark mass <math><msub><mi>m</mi><mi>q</mi></msub></math>, the QCD scale <math><msub><mi>Λ</mi><mi>QCD</mi></msub></math>, the pion mass <math><msub><mi>m</mi><mi>π</mi></msub></math>, and the pion decay constant <math><msub><mi>f</mi><mi>π</mi></msub></math> without any other experimental data. We make use of the form-factor bootstrap recently proposed by Karateev, Kuhn, and Penedones together with a finite energy version of the Shifman-Veinshtein-Zakharov sum rules.

France

United States

Gauge Theory Bootstrap

We propose to measure the energy correlator in quarkonium production, which tracks the energy deposited in the calorimeter at the <math><mrow><mi>χ</mi></mrow></math>-angular distance away from the identified quarkonium. The observable eliminates the need for jets while sustaining the perturbative predictive power. Analyzing the power correction to the energy correlator, we demonstrate that the novel observable supplies a unique gateway to probing the hadronization, especially when <math><mrow><mi>cos</mi><mi>χ</mi><mo>≳</mo><mn>0</mn></mrow></math> in the quarkonium rest frame, where the perturbative emissions are depleted due to the dead-cone effects. We expect the quarkonium energy correlator to add a new dimension to quarkonium studies.

China

Shedding Light on Hadronization by Quarkonium Energy Correlator

We show that crossing symmetry of <math><mrow><mi>S</mi></mrow></math> matrices is modified in certain theories with noninvertible symmetries or anomalies. Focusing on integrable flows to gapped phases in two dimensions, we find that <math><mrow><mi>S</mi></mrow></math> matrices derived previously from the bootstrap approach are incompatible with noninvertible symmetries along the flow. We present consistent alternatives, which, however, violate standard crossing symmetry and obey modified rules dictated by fusion categories. We extend these rules to theories with discrete anomalies.

United Kingdom

CERN

Noninvertible Symmetries, Anomalies, and Scattering Amplitudes

We formulate spacetime inequalities applicable to quantum-corrected black holes to all orders of backreaction in semiclassical gravity. Namely, we propose refined versions of the quantum Penrose and reverse isoperimetric inequalities, valid for all known three-dimensional asymptotically anti–de Sitter quantum black holes. Previous proposals of the quantum Penrose inequality apply in higher dimensions but fail when applied in three dimensions beyond the perturbative regime. Our quantum Penrose inequality, valid in three dimensions, holds at all orders of backreaction. This suggests cosmic censorship must exist in nonperturbative semiclassical gravity. Our quantum reverse isoperimetric inequality implies a maximum entropy state for quantum black holes at fixed volume.

Spain

Italy

Quantum Inequalities for Quantum Black Holes

We report the first lattice QCD computation of pion and kaon electromagnetic form factors, <math><mrow><msub><mrow><mi>F</mi></mrow><mrow><mi>M</mi></mrow></msub><mo>(</mo><msup><mrow><mi>Q</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>)</mo></mrow></math>, at large momentum transfer up to 10 and <math><mn>28</mn><mtext> </mtext><mtext> </mtext><msup><mi>GeV</mi><mn>2</mn></msup></math>, respectively. Utilizing physical masses and two fine lattices, we achieve good agreement with JLab experimental results at <math><msup><mi>Q</mi><mn>2</mn></msup><mo>≲</mo><mn>4</mn><mtext> </mtext><mtext> </mtext><msup><mi>GeV</mi><mn>2</mn></msup></math>. For <math><msup><mi>Q</mi><mn>2</mn></msup><mo>≳</mo><mn>4</mn><mtext> </mtext><mtext> </mtext><msup><mi>GeV</mi><mn>2</mn></msup></math>, our results provide ab initio QCD benchmarks for the forthcoming experiments at JLab 12 GeV and future electron-ion colliders. We also test the QCD collinear factorization framework utilizing our high-<math><msup><mi>Q</mi><mn>2</mn></msup></math> form factors at next-to-next-to-leading order in perturbation theory, which relates the form factors to the leading Fock-state meson distribution amplitudes. Comparisons with independent lattice QCD calculations using the same framework demonstrate, within estimated uncertainties, the universality of these nonperturbative quantities.

QCD Predictions for Meson Electromagnetic Form Factors at High Momenta: Testing Factorization in Exclusive Processes

We use analytic continuation to extend the gauge-gravity duality nonperturbative description of the strong force coupling into the transition, near-perturbative, regime where perturbative effects become important. By excluding the unphysical region in coupling space from the flow of singularities in the complex plane, we derive a specific relation between the scales relevant at large and short distances; this relation is uniquely fixed by requiring maximal analyticity. The unified effective coupling model gives an accurate description of the data in the nonperturbative and the near-perturbative regions.

Costa Rica

Germany

QCD Running Coupling in the Nonperturbative and Near-Perturbative Regimes

We present a mechanism for producing a cosmologically significant relic density of one or more sterile neutrinos. This scheme invokes two steps: First, a population of “heavy” sterile neutrinos is created by scattering-induced decoherence of active neutrinos. Second, this population is transferred, via sterile neutrino self-interaction-mediated scatterings and decays, to one or more lighter mass (<math><mrow><mo>∼</mo><mn>10</mn><mtext> </mtext><mtext> </mtext><mi>keV</mi></mrow></math> to <math><mo>∼</mo><mn>1</mn><mtext> </mtext><mtext> </mtext><mi>GeV</mi></math>) sterile neutrinos that are far more weakly (or not at all) mixed with active species and could constitute dark matter. Dark matter produced this way can evade current electromagnetic and structure-based bounds, but may nevertheless be probed by future observations.

Dark Population Transfer Mechanism for Sterile Neutrino Dark Matter

High-intensity neutron beams, such as those available at the European Spallation Source (ESS), provide new opportunities for fundamental discoveries. Here, we discuss a novel Ramsey neutron-beam experiment to search for ultralight axion dark matter through its coupling to neutron spins, which would cause the neutron spins to rotate about the velocity of the neutrons relative to the dark matter halo. We estimate that experiments at the HIBEAM beamline with a 50 m free flight path at the ESS can improve the sensitivity to the axion-neutron coupling compared to the current best laboratory limits by up to 2–3 orders of magnitude over the axion mass range <math><mrow><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>22</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi><mi>–</mi><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>16</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi></mrow></math>.

Sweden

Australia

Proposal for a Ramsey Neutron-Beam Experiment to Search for Ultralight Axion Dark Matter at the European Spallation Source

The <math><mrow><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup><mo>→</mo><msubsup><mrow><mi>D</mi></mrow><mrow><mi>s</mi></mrow><mrow><mo>+</mo></mrow></msubsup><msub><mrow><mi>D</mi></mrow><mrow><mi>s</mi><mn>1</mn></mrow></msub><mo>(</mo><mn>2536</mn><msup><mrow><mo>)</mo></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> and <math><mrow><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup><mo>→</mo><msubsup><mrow><mi>D</mi></mrow><mrow><mi>s</mi></mrow><mrow><mo>+</mo></mrow></msubsup><msubsup><mrow><mi>D</mi></mrow><mrow><mi>s</mi><mn>2</mn></mrow><mrow><mo>*</mo></mrow></msubsup><mo>(</mo><mn>2573</mn><msup><mrow><mo>)</mo></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> processes are studied using data samples collected with the BESIII detector at center-of-mass energies from 4.530 to 4.946 GeV. The absolute branching fractions of <math><mrow><msub><mrow><mi>D</mi></mrow><mrow><mi>s</mi><mn>1</mn></mrow></msub><mo>(</mo><mn>2536</mn><msup><mrow><mo>)</mo></mrow><mrow><mo>−</mo></mrow></msup><mo>→</mo><msup><mrow><mover><mrow><mi>D</mi></mrow><mrow><mo>¯</mo></mrow></mover></mrow><mrow><mo>*</mo><mn>0</mn></mrow></msup><msup><mrow><mi>K</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> and <math><msubsup><mi>D</mi><mrow><mi>s</mi><mn>2</mn></mrow><mo>*</mo></msubsup><mo>(</mo><mn>2573</mn><msup><mo>)</mo><mo>−</mo></msup><mo>→</mo><msup><mover><mi>D</mi><mo>¯</mo></mover><mn>0</mn></msup><msup><mi>K</mi><mo>−</mo></msup></math> are measured for the first time to be <math><mo>(</mo><mn>35.9</mn><mo>±</mo><mn>4.8</mn><mo>±</mo><mn>3.5</mn><mo>)</mo><mo>%</mo></math> and <math><mo>(</mo><mn>37.4</mn><mo>±</mo><mn>3.1</mn><mo>±</mo><mn>4.6</mn><mo>)</mo><mo>%</mo></math>, respectively. The <math><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo>→</mo><msubsup><mi>D</mi><mi>s</mi><mo>+</mo></msubsup><msub><mi>D</mi><mrow><mi>s</mi><mn>1</mn></mrow></msub><mo>(</mo><mn>2536</mn><msup><mo>)</mo><mo>−</mo></msup></math> and <math><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup><mo>→</mo><msubsup><mi>D</mi><mi>s</mi><mo>+</mo></msubsup><msubsup><mi>D</mi><mrow><mi>s</mi><mn>2</mn></mrow><mo>*</mo></msubsup><mo>(</mo><mn>2573</mn><msup><mo>)</mo><mo>−</mo></msup></math> cross sections are measured, and a resonant structure at around 4.6 GeV with a width of 50 MeV is observed in both processes with a statistical significance of <math><mn>7.2</mn><mi>σ</mi></math> and <math><mn>15</mn><mi>σ</mi></math>, respectively. The state is observed for the first time in <math><mrow><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup><mo>→</mo><msubsup><mrow><mi>D</mi></mrow><mrow><mi>s</mi></mrow><mrow><mo>+</mo></mrow></msubsup><msubsup><mrow><mi>D</mi></mrow><mrow><mi>s</mi><mn>2</mn></mrow><mrow><mo>*</mo></mrow></msubsup><mo>(</mo><mn>2573</mn><msup><mrow><mo>)</mo></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> and could be the <math><mi>Y</mi><mo>(</mo><mn>4626</mn><mo>)</mo></math> found by the Belle oration in the <math><msubsup><mi>D</mi><mi>s</mi><mo>+</mo></msubsup><msub><mi>D</mi><mrow><mi>s</mi><mn>1</mn></mrow></msub><mo>(</mo><mn>2536</mn><msup><mo>)</mo><mo>−</mo></msup></math> final state, since they have similar masses and widths. There is also evidence for a structure at around 4.75 GeV in both processes.

Russia

JINR

Poland

Mongolia

Türkiye

South Korea

Study of the Decay and Production Properties of <math><mrow><msub><mrow><mi>D</mi></mrow><mrow><mi>s</mi><mn>1</mn></mrow></msub><mo>(</mo><mn>2536</mn><mo>)</mo></mrow></math> and <math><mrow><msubsup><mrow><mi>D</mi></mrow><mrow><mi>s</mi><mn>2</mn></mrow><mrow><mo>*</mo></mrow></msubsup><mo>(</mo><mn>2573</mn><mo>)</mo></mrow></math>