We study two- and three-gluon glueballs of $C=+$ using the method of QCD sum rules. We systematically construct their interpolating currents, and find that all the spin-1 currents of $C=+$ vanish. This suggests that the “ground-state” spin-1 glueballs of $C=+$ do not exist within the relativistic framework. We calculate masses of the two-gluon glueballs with $J^{PC}=0^{\pm +}/2^{\pm +}$ and the three-gluon glueballs with $J^{PC}=0^{\pm +}/2^{\pm +}$. We propose searching for the $J^{PC}=0^{-+}/2^{-\pm }/3^{\pm -}$ three-gluon glueballs in their three-meson decay channels in the future BESIII, GlueX, LHC, and PANDA experiments.

We report predictions for the suppression and elliptic flow of the $\mathrm{\Upsilon }(1S)$, $\mathrm{\Upsilon }(2S)$, and $\mathrm{\Upsilon }(3S)$ as a function of centrality and transverse momentum in ultrarelativistic heavy-ion collisions. We obtain our predictions by numerically solving a Lindblad equation for the evolution of the heavy-quarkonium reduced density matrix derived using potential nonrelativistic QCD and the formalism of open quantum systems. To numerically solve the Lindblad equation, we make use of a stochastic unraveling called the quantum trajectories algorithm. This unraveling allows us to solve the Lindblad evolution equation efficiently on large lattices with no angular momentum cutoff. The resulting evolution describes the full 3D quantum and non-Abelian evolution of the reduced density matrix for bottomonium states. We expand upon our previous work by treating differential observables and elliptic flow; this is made possible by a newly implemented Monte Carlo sampling of physical trajectories. Our final results are compared to experimental data collected in $\sqrt{s_{NN}}=5.02\mathrm{TeV}$ Pb-Pb collisions by the ALICE, ATLAS, and CMS collaborations.

The dark (or hidden) photon is a massive U(1) gauge boson theorized as a dark force mediator and as a dark matter candidate. Dark photons can be detected with axion cavity haloscopes by probing for a power excess caused by the dark photon’s kinetic mixing with Standard Model photons. Haloscope axion exclusion limits may therefore be converted into competitive dark photon parameter limits via the calculation of a corresponding dark photon to photon coupling factor. This calculation allows for an improvement in sensitivity of around 4 orders of magnitude relative to other dark photon exclusions and may be attained using existing data. We present how one converts haloscope axion search limits and a summary of relevant experimental parameters from published searches. In addition, we have included the code that can be used to generate our dark photon exclusion limits for the cases described in this paper. Finally, we present limits on the kinetic mixing coefficient between dark photons and the Standard Model photons based on existing haloscope axion searches.

Many beyond Standard Model physics signatures are enhanced in high-energy neutrino interactions, beyond the energies achievable with accelerator neutrino sources. Atmospheric neutrinos can provide access to this high-energy regime, but their rapidly falling flux means that only a few muon neutrinos above 100 GeV can be observed interacting within a 10 kt DUNE far detector module each year. It is instead possible to exploit the long-lived muons created by charged current muon neutrino interactions below the detector. Above 100 GeV, a DUNE far detector module can observe approximately 230 such events per year. Existing ultralarge neutrino detectors have difficulty reconstructing the energy of muons between 50 GeV and 1 TeV, presenting an opportunity for DUNE to explore this energy regime with the fine-grained information from its liquid Argon time projection chamber technology. In this paper we point out that interesting beyond Standard Model signatures may appear in this energy window, and that early running of the DUNE far detectors can give insight into new physics that may appear in this range. We explore and report sensitivities for two such scenarios, a $3+1$ sterile neutrino model with nonzero ${\theta }_{34}$, and a Lorentz invariance violating standard model extension.

Measurements of differential and double-differential cross sections of top-quark pair ($t\overline{t}$) production are presented in the $\mathrm{lepton}+\text{jets}$ channels with a single electron or muon and jets in the final state. The analysis combines for the first time signatures of top quarks with low transverse momentum $p_{\mathrm{T}}$, where the top-quark decay products can be identified as separated jets and isolated leptons, and with high $p_{\mathrm{T}}$, where the decay products are collimated and overlap. The measurements are based on proton-proton collision data at $\sqrt{s}=13\mathrm{TeV}$ collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of $137{\mathrm{fb}}^{-1}$. The cross sections are presented at the parton and particle levels, where the latter minimizes extrapolations based on theoretical assumptions. Most of the measured differential cross sections are well described by standard model predictions with the exception of some double-differential distributions. The inclusive $t\overline{t}$ production cross section is measured to be ${\sigma }_{t\overline{t}}=791\pm 25\mathrm{pb}$, which constitutes the most precise measurement in the $\mathrm{lepton}+\text{jets}$ channel to date.

Taking the recently reported nonzero rotation angle of the cosmic microwave background (CMB) linear polarization $\beta =0.35\pm 0.14\mathrm{deg}$ as the hint for a pseudo–Nambu-Goldstone boson quintessence dark energy (DE), we study the electroweak (EW) axion quintessence DE model where the axion mass is generated by the EW instantons. We find that the observed value of $\beta$ implies a nontrivial $U(1)$ electromagnetic anomaly coefficient ($c_{\gamma }$), once the current constraint on the DE equation of state is also taken into account. With the aid of the hypothetical high energy structure of the model inspired by the experimentally inferred $c_{\gamma }$, the model is shown to be able to make a prediction for the current equation of state ($w_{\mathrm{DE},0}$) of the quintessence DE. This is expected to make our scenario distinguishable in comparison with the cosmological constant ($w=-1$) and testable in the future when the error in the future measurement of $w_{\mathrm{DE},0}$ is reduced to $\mathcal{O}(1)\%$ level ($\delta w=\mathcal{O}({10}^{-2})$).

The recent LHCb data on $B_s^0\to J/\psi p\overline{p}$ revealed a new pentaquark-like $P_c(4337{)}^{+}$ structure, while finding no evidence for $P_c(4312{)}^{+}$ discovered earlier in ${\mathrm{\Lambda }}_b^0\to J/\psi p{K}^{-}$. Though puzzling, the data actually offer an important hint to understand the nature of the pentaquark candidates. We develop a model to analyze the $B_s^0\to J/\psi p\overline{p}$ data. We find that a ${\mathrm{\Sigma }}_c\overline{D}$ one-loop mechanism causes a threshold cusp that fits well the $P_c(4337{)}^{+}$ peak. Also, the ${\mathrm{\Sigma }}_c\overline{D}$ and ${\mathrm{\Lambda }}_c{\overline{D}}^{*}$ threshold cusps interfere with each other to reproduce an oscillating behavior in the proton helicity angle distribution. These results combined with our earlier analysis on ${\mathrm{\Lambda }}_b^0\to J/\psi p{K}^{-}$ indicate that $P_c(4312{)}^{+}$ and $P_c(4337{)}^{+}$ are created by different interference patterns between the ${\mathrm{\Sigma }}_c\overline{D}$ and ${\mathrm{\Lambda }}_c{\overline{D}}^{*}$ (anomalous) threshold cusps. The proposed scenario consistently explains why the $P_c(4312{)}^{+}$ and $P_c(4337{)}^{+}$ peaks appear in ${\mathrm{\Lambda }}_b^0\to J/\psi p{K}^{-}$ and $B_s^0\to J/\psi p\overline{p}$, respectively, but not vice versa or both.

The ratios $R_{\tau /P}\equiv \mathrm{\Gamma }(\tau \to P{\nu }_{\tau }[\gamma ])/\mathrm{\Gamma }(P\to \mu {\nu }_{\mu }[\gamma ])$ ($P=\pi$, $K$) provide sensitive tests of lepton universality $|g_{\tau }/g_{\mu }|=1$ and are a useful tool for new physics searches. The radiative corrections to $R_{\tau /P}$ are computed following a large-$N_C$ expansion to deal with hadronic effects: Chiral Perturbation Theory is enlarged by including the lightest multiplets of spin-one heavy states such that the relevant Green functions are well behaved at high energies. We find $\delta R_{\tau /\pi }=(0.18\pm 0.57)\%$ and $\delta R_{\tau /K}=(0.97\pm 0.58)\%$, which imply ${|g_{\tau }/g_{\mu }|}_{\pi }=0.9964\pm 0.0038$ and ${|g_{\tau }/g_{\mu }|}_K=0.9857\pm 0.0078$, compatible with and at $1.8\sigma$ of lepton universality, respectively. We test unitarity and bind nonstandard effective interactions with the $\tau \to P{\nu }_{\tau }[\gamma ]$ decays.

In QCD, the amplitude for multiple soft gluon emissions has been shown to exhibit a form of coherence, wherein one-loop corrections are rendered IR finite by the transverse momentum of the real emissions. Using a sequence of soft-collinear effective theories (SCET) with Glauber operators, we present a compact and elegant derivation of this property. Our derivation highlights an important role played by the Lipatov vertex. The EFT approach provides increased physical intuition and, for the first time, a clear road map for how this result can be extended to higher loop orders.

We present a search for the lepton-flavor-violating decays $B^0\to {\tau }^{\pm }{\ell }^{\mp }$, where $\ell =(e,\mu )$, using the full data sample of $772\times {10}^{6}B\overline{B}$ pairs recorded by the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider. We use events in which one $B$ meson is fully reconstructed in a hadronic decay mode. The ${\tau }^{\pm }$ lepton is reconstructed indirectly using the momentum of the reconstructed $B$ and that of the ${\ell }^{\mp }$ from the signal decay. We find no evidence for $B^0\to {\tau }^{\pm }{\ell }^{\mp }$ decays and set upper limits on their branching fractions at 90% confidence level of $\mathcal{B}(B^0\to {\tau }^{\pm }{\mu }^{\mp })<1.5\times {10}^{-5}$ and $\mathcal{B}(B^0\to {\tau }^{\pm }{e}^{\mp })<1.6\times {10}^{-5}$.

The Born cross section of the process $e^{+}{e}^{-}\to \mathrm{\Lambda }\overline{\mathrm{\Lambda }}$ is measured at 33 center-of-mass energies between 3.51 and 4.60 GeV using data corresponding to the total integrated luminosity of $20.0{\mathrm{fb}}^{-1}$ collected with the BESIII detector at the BEPCII collider. Describing the energy dependence of the cross section requires a contribution from the $\psi (3770)\to \mathrm{\Lambda }\overline{\mathrm{\Lambda }}$ decay, which is fitted with a significance of $4.6-4.9\sigma$ including the systematic uncertainty. The lower bound on its branching fraction is $2.4\times {10}^{-6}$ at the 90% confidence level (C.L.), at least an order of magnitude larger than expected from predictions using a scaling based on observed electronic widths. This result indicates the importance of effects from vector charmonium(like) states when interpreting data in terms of e.g., electromagnetic structure observables. The data do not allow for definite conclusions on the interplay with other vector charmonium(like) states, and we set 90% C.L. upper limits for the products of their electronic widths and the branching fractions.

By analyzing an $e^{+}{e}^{-}$ annihilation data sample corresponding to an integrated luminosity of $2.93{\mathrm{fb}}^{-1}$ collected at a center-of-mass energy of 3.773 GeV with the BESIII detector, we measure the branching fraction of the $D^0\to {\rho }^{-}{\mu }^{+}{\nu }_{\mu }$ decay for the first time. We obtain ${\mathcal{B}}_{D^0\to {\rho }^{-}{\mu }^{+}{\nu }_{\mu }}=(1.35\pm {0.09}_{\mathrm{stat}}\pm {0.09}_{\mathrm{syst}})\times {10}^{-3}$. Using the world average of ${\mathcal{B}}_{D^0\to {\rho }^{-}{e}^{+}{\nu }_e}$, we find a branching fraction ratio of ${\mathcal{B}}_{D^0\to {\rho }^{-}{\mu }^{+}{\nu }_{\mu }}/{\mathcal{B}}_{D^0\to {\rho }^{-}{e}^{+}{\nu }_e}=0.90\pm 0.11$, which agrees with the theoretical expectation of lepton flavor universality within the uncertainty. Combining the world average of ${\mathcal{B}}_{D^{+}\to {\rho }^0{\mu }^{+}{\nu }_{\mu }}$ and the lifetimes of $D^{0(+)}$, we obtain a partial decay width ratio of ${\mathrm{\Gamma }}_{D^0\to {\rho }^{-}{\mu }^{+}{\nu }_{\mu }}/(2{\mathrm{\Gamma }}_{D^{+}\to {\rho }^0{\mu }^{+}{\nu }_{\mu }})=0.71\pm 0.14$, which is consistent with the isospin symmetry expectation of unity within $2.1\sigma$. For the reported values of ${\mathcal{B}}_{D^0\to {\rho }^{-}{\mu }^{+}{\nu }_{\mu }}/{\mathcal{B}}_{D^0\to {\rho }^{-}{e}^{+}{\nu }_e}$ and ${\mathrm{\Gamma }}_{D^0\to {\rho }^{-}{\mu }^{+}{\nu }_{\mu }}/2{\mathrm{\Gamma }}_{D^{+}\to {\rho }^0{\mu }^{+}{\nu }_{\mu }}$, the uncertainty is the quadratic sum of the statistical and systematic uncertainties.

In this article, we prove that for all five-dimensional supergravities arising from M theory compactified on a Calabi-Yau threefold, points of vanishing gauge coupling lie at infinite distance in the moduli space. Conversely, any point at infinite distance in the vector multiplet moduli space is a point of vanishing gauge coupling. This agrees with expectations from the tower/sublattice weak gravity conjecture, the swampland distance conjecture, and the emergence proposal.

We analyze families of particle detector models that linearly couple to different kinds of fermionic and bosonic fields. We also study the response of these detectors to particle and antiparticle excitations of the field. We propose a simple linear complex scalar particle detector model that captures the fundamental features of fermionic field detectors similarly to how the Unruh-DeWitt model captures the features of the light matter interaction. We also discuss why we do not need to limit ourselves to quadratic models commonly employed in past literature. Namely, we provide a physically motivated mechanism that restores U(1) symmetry in these linear complex models.

Motivated by the fact that the null shell of a collapsing black hole can be described by a perfectly reflecting accelerating mirror, we investigate an extension of this model to mirror semitransparency and derive a general implicit expression for the corresponding Bogolyubov coefficients. Then, we turn this into an explicit analytical form by focusing on mirrors that are accelerated via an impulsive force. From the so-obtained Bogolyubov coefficients we derive the particle production. Finally, we realize the field coming from the left-past spacetime region, passing through the semitransparent moving mirror and ending up to the right-future spacetime region as undergoing the action of a Gaussian quantum channel. We study the transmission and noisy generation properties of this channel, relating them to the Bogolyubov coefficients of the mirror’s motion, through which we evaluate capacities in transmitting classical and quantum information.

The Fock-Schwinger proper-time method is used to derive the effective action in the field theory with the chiral $U(3)\times U(3)$ symmetry explicitly broken by unequal masses of heavy particles. The one-loop effective action is presented as a series in inverse powers of heavy masses. The first two Seeley-DeWitt coefficients of this expansion are explicitly calculated. This powerful technique opens a promising avenue for studying explicit flavor symmetry-breaking effects in the effective field theories.

Statistically sound tests of scalar-tensor gravity theories in the strong-field regime usually involve computationally intensive calculations. In this study, we construct a reduced order surrogate model for the scalar-tensor gravity of Damour and Esposito-Farèse (DEF) with spontaneous scalarization phenomena developed for neutron stars (NSs). This model allows us to perform a rapid and comprehensive prediction of NS properties, including mass, radius, moment of inertia, effective scalar coupling, and two extra coupling parameters. We code the model in the pystgromx package, as an extension of our previous work, which speeds up the calculations at 2 and even 3 orders of magnitude and yet still keeps accuracy of $\sim 1\%$. Using the model, we can calculate all the post-Keplerian parameters in the timing of binary pulsars conveniently, which provides a quick approach for us to place comprehensive constraints on the DEF theory. We perform Markov-chain Monte Carlo simulations with the model to constrain the parameters of the DEF theory with well-timed binary pulsars. Utilizing five NS-white dwarf and three NS-NS binaries, we obtain the most stringent constraints on the DEF theory up to now. Our work provides a public tool for quick evaluation of NSs’ derived parameters to test gravity in the strong-field regime.

Inflationary dynamics driven by multiple fields, especially with nonminimal couplings, allows for highly interesting features such as isocurvature, non-Gaussianity, and preheating. In this paper, we study two-field inflation in the context of purely affine gravity, where the metrical structure results from the dynamics of the spacetime affine connection. We introduce a covariant formulation in the new framework and show that it leads to a curved field space which can produce conspicuous departure from the purely metric gravity. In the case where the fields are canonical, the field manifold gains a conformally flat shape. Interestingly, while the manifold is generally curved, it is possible to be flattened by allowing a specific noncanonical field kinetic terms. This in turn simplifies the inflationary dynamics significantly while allowing for new predictions due to the effects of the nonminimal coupling function on the potential solely. We use this new feature in studying two-field inflation driven by quartic potentials for given parameter constants. We perform a numerical solution of the slow-roll dynamics and track the possible non-Gaussianity. We focus on field parameters that allow for spectral indices within the favored region of the Planck results. These are associated to tiny tensor-to-scalar ratios, $r\sim {10}^{-6}$ for single field and $r\sim {10}^{-4}$ for two-fields. We also show that two-field Higgs inflation may favor a curved field manifold.

We develop an analytical ringdown waveform model, including both the fundamental and the overtone quasinormal modes, for charged black holes and show that it is precise enough to analyze current gravitational wave data. Applying this waveform model to GW150914, the charge to mass ratio of the remnant black hole (${\lambda }_f$) has been constrained with the sole ringdown gravitational wave data for the first time and the 90% upper limit is ${\lambda }_f\le 0.38$. Correspondingly, the deviation parameter of the scalar-tensor vector gravity (${\alpha }_{\mathrm{s}}$) is limited to be ${\alpha }_{\mathrm{s}}\le 0.17$. Our approach can be directly applied to other binary black hole mergers with loud ringdown radiation.

$k$ essence is a minimally coupled scalar field whose Lagrangian density $\mathcal{L}$ is a function of the field value $\varphi$ and the kinetic energy $X=\frac{1}{2}{\partial }_{\mu }\varphi {\partial }^{\mu }\varphi$. In the thawing scenario, the scalar field is frozen by the large Hubble friction in the early Universe, and therefore initial conditions are specified. We construct thawing $k$-essence models by generating Taylor expansion coefficients of $\mathcal{L}(\varphi ,X)$ from random matrices. From the ensemble of randomly generated thawing $k$-essence models, we select dark energy candidates by assuming negative pressure and nongrowth of subhorizon inhomogeneities. For each candidate model the dark energy equation of state function is fit to the Chevallier-Polarski-Linder parametrization $w(a)\approx w_0+w_a(1-a)$, where $a$ is the scale factor. The thawing $k$-essence dark models distribute very nonuniformly in the $(w_0,w_a)$ space. About 90% of models cluster in a narrow band in the proximity of a slow-roll line $w_a\approx -1.42{(\frac{{\mathrm{\Omega }}_m}{0.3})}^{0.64}(1+w_0)$, where ${\mathrm{\Omega }}_m$ is the present matter density fraction. This work is a proof of concept that for a certain class of models very nonuniform theoretical prior on $(w_0,w_a)$ can be obtained to improve the statistics of model selection.