We use QCD Laplace sum rules to study meson-hybrid mixing in vector ($1^{--}$) heavy quarkonium. We compute the QCD cross-correlator between a heavy meson current and a heavy hybrid current within the operator product expansion. In addition to leading-order perturbation theory, we include four- and six-dimensional gluon condensate contributions as well as a six-dimensional quark condensate contribution. We construct several single and multiresonance models that take known hadron masses as inputs. We investigate which resonances couple to both currents and so exhibit meson-hybrid mixing. Compared to single resonance models that include only the ground state, we find that models that also include excited states lead to significantly improved agreement between QCD and experiment. In the charmonium sector, we find that meson-hybrid mixing is consistent with a two-resonance model consisting of the $J/\psi$ and a 4.3 GeV resonance. In the bottomonium sector, we find evidence for meson-hybrid mixing in the $\mathrm{\Upsilon }(1S)$, $\mathrm{\Upsilon }(2S)$, $\mathrm{\Upsilon }(3S)$, and $\mathrm{\Upsilon }(4S)$.

Using a data sample of $980{\mathrm{fb}}^{-1}$ of $e^{+}{e}^{-}$ annihilation data taken with the Belle detector operating at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider, we report the results of a study of the decays of the ${\mathrm{\Omega }}_c^0$ charmed baryon into hadronic final states. We report the most precise measurements to date of the relative branching fractions of the ${\mathrm{\Omega }}_c^0$ into ${\mathrm{\Omega }}^{-}{\pi }^{+}{\pi }^0$, ${\mathrm{\Omega }}^{-}{\pi }^{+}{\pi }^{-}{\pi }^{+}$, ${\mathrm{\Xi }}^{-}{K}^{-}{\pi }^{+}{\pi }^{+}$, and ${\mathrm{\Xi }}^0{K}^{-}{\pi }^{+}$, as well as the first measurements of the branching fractions of the ${\mathrm{\Omega }}_c^0$ into ${\mathrm{\Xi }}^{-}{\overline{K}}^0{\pi }^{+}$, ${\mathrm{\Xi }}^0{\overline{K}}^0$, and $\mathrm{\Lambda }{\overline{K}}^0{\overline{K}}^0$, all with respect to the ${\mathrm{\Omega }}^{-}{\pi }^{+}$ decay. In addition, we investigate the resonant substructure of these modes. Finally, we present a limit on the branching fraction for the decay ${\mathrm{\Omega }}_c^0\to {\mathrm{\Sigma }}^{+}{K}^{-}{K}^{-}{\pi }^{+}$.

The electrons in graphene for energies close to the Dirac point have been found to form strongly interacting fluid. Taking this fact into account we have extended previous work on the transport properties of graphene by taking into account possible interactions between the currents and adding the external magnetic field directed perpendicularly to the graphene sheet. The perpendicular magnetic field $B$ severely modifies the transport parameters. In the present approach the quantization of the spectrum and formation of Landau levels is ignored. Gauge/gravity duality has been used in the probe limit. The dependence on the charge density of the Seebeck coefficient and thermoelectric parameters ${\alpha }^{ij}$ nicely agree with recent experimental data for graphene. The holographic model allows for the interpretation of one of the fields representing the currents as resulting from the dark matter sector. For the studied geometry with electric field perpendicular to the thermal gradient the effect of the dark sector has been found to modify the transport parameters but mostly in a quantitative way only. This makes difficult the detection of this elusive component of the Universe by studying transport properties of graphene.

Localizing sources on the sky is crucial for realizing the full potential of gravitational waves for astronomy, astrophysics, and cosmology. We show that the midfrequency band, roughly 0.03 to 10 Hz, has significant potential for angular localization. The angular location is measured through the changing Doppler shift as the detector orbits the Sun. This band maximizes the effect since these are the highest frequencies in which sources live for several months. Atom interferometer detectors can observe in the midfrequency band, and even with just a single baseline they can exploit this effect for sensitive angular localization. The single-baseline orbits around the Earth and the Sun, causing it to reorient and change position significantly during the lifetime of the source, and making it similar to having multiple baselines/detectors. For example, atomic detectors could predict the location of upcoming black hole or neutron star merger events with sufficient accuracy to allow optical and other electromagnetic telescopes to observe these events simultaneously. Thus, midband atomic detectors are complementary to other gravitational wave detectors and will help complete the observation of a broad range of the gravitational spectrum.

In this paper we design a search for continuous gravitational waves from three supernova remnants: Vela Jr., Cassiopeia A (Cas A) and G347.3. These systems might harbor rapidly rotating neutron stars emitting quasiperiodic gravitational radiation detectable by the advanced LIGO detectors. Our search is designed to use the volunteer computing project Einstein@Home for a few months and assumes the sensitivity and duty cycles of the advanced LIGO detectors during their first science run. For all three supernova remnants, the sky positions of their central compact objects are well known but the frequency and spin-down rates of the neutron stars are unknown which makes the searches computationally limited. In a previous paper we have proposed a general framework for deciding on what target we should spend computational resources and in what proportion, what frequency and spin-down ranges we should search for every target, and with what search setup. Here we further expand this framework and apply it to design a search directed at detecting continuous gravitational wave signals from the most promising three supernova remnants identified as such in the previous work. Our optimization procedure yields broad frequency and spin-down searches for all three objects, at an unprecedented level of sensitivity: The smallest detectable gravitational wave strain $h_0$ for Cas A is expected to be 2 times smaller than the most sensitive upper limits published to date, and our proposed search, which was set up and ran on the volunteer computing project Einstein@Home, covers a much larger frequency range.

The recently proposed chameleonic extension of bigravity theory, by including a scalar field dependence in the graviton potential, avoids several fine-tunings found to be necessary in usual massive bigravity. In particular it ensures that the Higuchi bound is satisfied at all scales, that no Vainshtein mechanism is needed to satisfy Solar System experiments, and that the strong coupling scale is always above the scale of cosmological interest all the way up to the early Universe. This paper extends the previous work by presenting a stable example of cosmology in the chameleon bigravity model. We find a set of initial conditions and parameters such that the derived stability conditions on general flat Friedmann background are satisfied at all times. The evolution goes through radiation-dominated, matter-dominated, and de Sitter eras. We argue that the parameter space allowing for such a stable evolution may be large enough to encompass an observationally viable evolution. We also argue that our model satisfies all known constraints due to gravitational wave observations so far and thus can be considered as a unique testing ground of gravitational wave phenomenologies in bimetric theories of gravity.

In recent years, superfluid dark matter (SfDM) has become a competitive model of emergent modified Newtonian dynamics (MOND) scenario: MOND phenomenons naturally emerge as a derived concept due to an extra force mediated between baryons by phonons as a result of axionlike particles condensed as superfluid at galactic scales; Beyond galactic scales, these axionlike particles behave as normal fluid without phonon-mediated MOND-like force between baryons, therefore SfDM also maintains the usual success of $\mathrm{\Lambda }\mathrm{CDM}$ at cosmological scales. In this paper, we use gravitational waves (GWs) to probe the relevant parameter space of SfDM. GWs through Bose-Einstein condensate (BEC) could propagate with a speed slightly deviation from the speed-of-light due to the change in the effective refractive index, which depends on the SfDM parameters and GW-source properties. We find that Five hundred meter Aperture Spherical Telescope (FAST), Square Kilometre Array (SKA) and International Pulsar Timing Array (IPTA) are the most promising means as GW probe of relevant parameter space of SfDM. Future space-based GW detectors are also capable of probing SfDM if a multimessenger approach is adopted.

We show that the space of solutions of a wide class of Ricci-based metric-affine theories of gravity can be put into correspondence with the space of solutions of general relativity (GR). This allows us to use well-established methods and results from GR to explore new gravitational physics beyond it.

We present scheme-independent calculations of the derivative of the beta function at an infrared (IR) fixed point, denoted ${\beta }_{\mathrm{IR}}^{\prime }$, in several asymptotically free chiral gauge theories, namely $\mathrm{SO}(4k+2)$ with $2\le k\le 4$ with respective numbers $N_f$ of fermions in the spinor representation, and ${\mathrm{E}}_6$ with fermions in the fundamental representation. Some implications of these results are discussed.

We consider an extension of the standard model (SM) augmented by two neutral singlet fermions per generation and a leptoquark. In order to generate the light neutrino masses and mixing, we incorporate inverse seesaw mechanism. The right-handed neutrino production in this model is significantly larger than the conventional inverse seesaw scenario. We analyze the different collider signatures of this model and find that the final states associated with three or more leptons, multijet and at least one $b$-tagged and (or) $\tau$-tagged jet can probe larger RH neutrino mass scale. We have also proposed a same-sign dilepton signal region associated with multiple jets and missing energy that can be used to distinguish the present scenario from the usual inverse seesaw extended SM.

We advocate for the construction of a new detector element at the LHCb experiment, designed to search for displaced decays of beyond Standard Model long-lived particles, taking advantage of a large shielded space in the LHCb cavern that is expected to soon become available. We discuss the general features and putative capabilities of such an experiment, as well as its various advantages and complementarities with respect to the existing LHC experiments and proposals such as SHiP and MATHUSLA. For two well-motivated beyond Standard Model benchmark scenarios—Higgs decay to dark photons and $B$ meson decays via a Higgs mixing portal—the reach either complements or exceeds that predicted for other LHC experiments.

We consider the standard model (SM) extended by the addition of a complex scalar singlet, with no assumptions about additional symmetries of the potential. This model provides for resonant di-Higgs production of Higgs particles with different masses. We demonstrate that regions of parameter space allowed by precision electroweak measurements, experimental limits on single Higgs production, and perturbative unitarity allow for large di-Higgs production rates relative to the SM rates. In this scenario, the dominant production mechanism of the new scalar states is di-Higgs production. Results are presented for $\sqrt{S}=13$, 27 and 100 TeV.

We conduct a systematic study of the impact of new physics in quark-level $b\to c\overline{c}s$ transitions on $B$ physics, in particular rare $B$ decays and $B$-meson lifetime observables. We find viable scenarios where a sizable effect in rare semileptonic $B$ decays can be generated, compatible with experimental indications and with a possible dependence on the dilepton invariant mass, while being consistent with constraints from radiative $B$ decay and the measured $B_s$ width difference. We show how, if the effect is generated at the weak scale or beyond, strong renormalization-group effects can enhance the impact on semileptonic decays while leaving radiative $B$ decay largely unaffected. A good complementarity of the different $B$-physics observables implies that precise measurements of lifetime observables at LHCb may be able to confirm, refine, or rule out this scenario.

We calculate the equation of state at high temperatures in $2+1$ flavor QCD using the highly improved staggered quark (HISQ) action. We study the lattice spacing dependence of the pressure at high temperatures using lattices with temporal extent $N_{\tau }=6$, 8, 10 and 12 and perform continuum extrapolations. We also give a continuum estimate for the equation of state up to temperatures $T=2\mathrm{GeV}$, which are then compared with results of the weak-coupling calculations. We find a reasonably good agreement with the weak-coupling calculations at the highest temperatures.

We derive the generalized Skyrme model as a low-energy effective model of the Sakai-Sugimoto model. The novelty with the past is the presence of the sextic term equal to the topological charge squared. This term appears when the $\omega$ meson, and the tower of states on top of it, are integrated out. We claim that, in the small ’t Hooft coupling limit, the instanton is well described by a Skyrmion arising from the low energy effective Lagrangian of the Sakai-Sugimoto model. The sextic term plays a dominant role in this limit. Moreover, when a pion mass term is added, we recover the BPS Skyrme model in the small ’t Hooft coupling limit.

We obtain the general expression of the gluon propagator at finite temperature ($T$) and in a magnetic field ($B$), for the case that the four transverse tensor structures appear in the gluon self-energy. By using this expression and a specific form of the one-loop gluon self-energy in the lowest Landau level approximation, we analyze the gluon spectrum in the strong magnetic field limit. As a result, we find that there exist two collective excitations of which the energies are of the order of $p\sim gT$ with $g$ being the coupling constant. One of the two excitations enjoys properties quite different from those of the collective excitations at $B=0$ which have been discussed by using the hard thermal loop approximation. We also discuss the static and dynamical screening effects, which are expected to be important for computation of transport coefficients in strong magnetic fields.

A search for supersymmetry is presented based on proton-proton collision events containing identified hadronically decaying top quarks, no leptons, and an imbalance $p_{\mathrm{T}}^{\mathrm{miss}}$ in transverse momentum. The data were collected with the CMS detector at the CERN LHC at a center-of-mass energy of 13 TeV, and correspond to an integrated luminosity of $35.9{\mathrm{fb}}^{-1}$. Search regions are defined in terms of the multiplicity of bottom quark jet and top quark candidates, the $p_{\mathrm{T}}^{\mathrm{miss}}$, the scalar sum of jet transverse momenta, and the $m_{\mathrm{T}2}$ mass variable. No statistically significant excess of events is observed relative to the expectation from the standard model. Lower limits on the masses of supersymmetric particles are determined at 95% confidence level in the context of simplified models with top quark production. For a model with direct top squark pair production followed by the decay of each top squark to a top quark and a neutralino, top squark masses up to 1020 GeV and neutralino masses up to 430 GeV are excluded. For a model with pair production of gluinos followed by the decay of each gluino to a top quark-antiquark pair and a neutralino, gluino masses up to 2040 GeV and neutralino masses up to 1150 GeV are excluded. These limits extend previous results.

WKB approximation methods are applied to the case of a massive scalar field around a five-dimensional Reissner-Nordström black hole. The divergences are explicitly isolated, and the cancellation against the Schwinger-DeWitt counterterms are proven. The resulting finite quantity is evaluated for different values of the free parameters, namely, the black hole mass and charge, and the scalar field mass. We thus extend our previous results on quantum vacuum polarization effects for uncharged asymptotically flat higher-dimensional black holes to electrically charged black holes.

We determine the retarded and advanced Green’s functions and Hadamard parametrices in curved spacetimes for linearized massive and massless gauge bosons and linearized Einstein gravity with a cosmological constant in general linear covariant gauges. These vector and tensor parametrices contain additional singular terms compared with their Feynman/de Donder-gauge counterpart. We also give explicit recursion relations for the Hadamard coefficients, and indicate their generalization to $n$ dimensions. Furthermore, we express the divergence and trace of the vector and tensor Green’s functions in terms of derivatives of scalar and vector Green’s functions, and show how these relations appear as Ward identities in the free quantum theory.

We revisit constraints on small-scale primordial power from annihilation signals from dark matter minihalos. Using gamma rays and neutrinos from extragalactic minihalos and assuming the delta-function primordial spectrum, we show the dependence of the constraints on annihilation modes, the mass of dark matter, and the annihilation cross section. We report conservative constraints by assuming minihalos are fully destructed when becoming part of halos originating from the standard almost-scale invariant primordial spectrum and optimistic constraints by neglecting destruction.