The SU(3)-flavor violating decay $J/\psi \to \mathrm{\Xi }(1530{)}^{-}{\overline{\mathrm{\Xi }}}^{+}+\mathrm{c}.\mathrm{c}.$ is studied using $(1310.6\pm 7.0)\times 10^6$ $J/\psi$ events collected with the BESIII detector at BEPCII, and the branching fraction is measured to be $\mathcal{B}(J/\psi \to \mathrm{\Xi }(1530{)}^{-}{\overline{\mathrm{\Xi }}}^{+}+\mathrm{c}.\mathrm{c}.)=(3.17\pm 0.02_{\text{stat}}\pm 0.08_{\text{syst}})\times 10^{-4}$. This result is consistent with previous measurements with an order of magnitude improved precision. The angular parameter for this decay is measured for the first time and is found to be $\alpha =-0.21\pm 0.04_{\text{stat}}\pm 0.06_{\text{syst}}$. In addition, we report evidence for the radiative decay $\mathrm{\Xi }(1530{)}^{-}\to \gamma {\mathrm{\Xi }}^{-}$ with a significance of $3.9\sigma$, including the systematic uncertainties. The 90% confidence level upper limit on the branching fraction is determined to be $\mathcal{B}(\mathrm{\Xi }(1530{)}^{-}\to \gamma {\mathrm{\Xi }}^{-})\le 3.7\%$.

Based on the systematic Hamiltonian and superfield approaches, we construct the deformed $\mathcal{N}=4$, 8 supersymmetric mechanics on Kähler manifolds interacting with a constant magnetic field and study their symmetries. First, we construct the deformed $\mathcal{N}=4$, 8 supersymmetric Landau problem via the minimal coupling of standard (undeformed) $\mathcal{N}=4$, 8 supersymmetric free particle systems on a Kähler manifold with a constant magnetic field. We show that the initial “flat” supersymmetries are necessarily deformed to $SU(2|1)$ and $SU(4|1)$ supersymmetries, with the magnetic field playing the role of a deformation parameter, and that the resulting systems inherit all the kinematical symmetries of the initial ones. Then we construct $SU(2|1)$ supersymmetric Kähler oscillators and find that they include, in particular cases, the harmonic oscillator models on complex Euclidian and complex projective spaces, as well as superintegrable deformations thereof, viz. ${\mathbb{C}}^N$-Smorodinsky-Winternitz and $\mathbb{C}{\mathbb{P}}^N$-Rosochatius systems. We show that the supersymmetric extensions proposed inherit all the kinematical symmetries of the initial bosonic models. They also inherit, at least in the case of the ${\mathbb{C}}^N$ systems, hidden (nonkinematical) symmetries. The superfield formulation of these supersymmetric systems is presented, based on the worldline $SU(2|1)$ and $SU(4|1)$ superspace formalisms.

We prove the stability of the critical hypersurfaces associated with the three-dimensional general relativistic Poynting-Robertson effect. The equatorial ring configures to be as a stable attractor and the whole critical hypersurface as a basin of attraction for this dynamical system. We introduce a new, simpler (in terms of calculations), and more physical approach within the Lyapunov theory. We propose three different Lyapunov functions, each one carrying important information and very useful for understanding such phenomenon under different aspects.

The self-force program aims at accurately modeling relativistic two-body systems with a small mass ratio (SMR). In the context of the effective-one-body (EOB) framework, current results from this program can be used to determine the effective metric components at linear order in the mass ratio, resumming post-Newtonian (PN) dynamics around the test-particle limit in the process. It was shown in [Akcay et al., Phys. Rev. D 86, 104041 (2012).] that, in the original (standard) EOB gauge, the SMR contribution to the metric component $g_{tt}^{\mathrm{eff}}$ exhibits a coordinate singularity at the light-ring (LR) radius. In this paper, we adopt a different gauge for the EOB dynamics and obtain a Hamiltonian that is free of poles at the LR, with complete circular-orbit information at linear order in the mass ratio and non-circular-orbit and higher-order-in-mass-ratio terms up to 3PN order. We confirm the absence of the LR divergence in such an EOB Hamiltonian via plunging trajectories through the LR radius. Moreover, we compare the binding energies and inspiral waveforms of EOB models with SMR, PN and mixed SMR-3PN information on a quasicircular inspiral against numerical-relativity predictions. We find good agreement between numerical-relativity simulations and EOB models with SMR-3PN information for both equal- and unequal-mass ratios. In particular, when compared to EOB inspiral waveforms with only 3PN information, EOB Hamiltonians with SMR-3PN information improves the modeling of binary systems with small mass ratios $q\lesssim 1/3$, with a dephasing accumulated in $\sim 30$ gravitational-wave (GW) cycles being of the order of few hundredths of a radian up to 4 GW cycles before merger.

We study spherically symmetric strongly gravitating configurations supported by nonlinear spinor fields and non-Abelian SU(2) Yang-Mills/Proca magnetic fields. Regular asymptotically flat solutions describing objects with positive Arnowitt-Deser-Misner masses are obtained numerically. When the mass of the spinor fields is much smaller than the Planck mass, we find approximate solutions that can describe systems with total masses comparable to the Chandrasekhar mass and with effective radii of the order of kilometers. For the values of the system free parameters used here, we show that the SU(2) magnetic field always gives a small contribution to the total energy density and mass of the configurations under investigation. From the astrophysical point of view, one can regard such objects as magnetized Dirac stars.

“Twisted particles” refer to non-plane-wave states of photons, electrons, hadrons, or any other particles which carry nonzero, adjustable orbital angular momentum with respect to their average propagation direction. Twisted photons and electrons have already been experimentally demonstrated, and one can expect creation of twisted states of other particles in the future. Such states can be brought in collisions, offering a completely new degree of freedom in collider experiments and, especially, a novel tool for hadronic physics. We recently showed that $2\to 1$ processes with two twisted particles such as resonance production in twisted $e^{+}{e}^{-}$ annihilation give access to observables which are difficult or impossible to probe in the usual plane wave collisions. In this paper, we discuss in detail surprising kinematic features of this process, focusing on spinless particle annihilation. They include 1) a new dimension in the final momentum space available in twisted annihilation, 2) interference fringes emerging in the cross section as a function of the total energy, and 3) the built-in mass spectrometric capability of this process, that is, simultaneous production and automatic angular separation of several resonances with different masses in monochromatic twisted particle annihilation experiment running at fixed energy. All these features cannot be obtained in the usual plane wave collision setting.

We explore the possibility that lepton family numbers and baryon number are such good symmetries of Nature because they are the global remnant of a spontaneously broken gauge symmetry. An almost arbitrary linear combination of these symmetries (together with a component of global hypercharge) can be consistently gauged, if the Standard Model (SM) fermion content is augmented by three chiral SM singlet states. Within this framework of $U(1)$ extensions of the SM one generically expects flavor nonuniversality to emerge in the charged leptons, in such a way that naturally prevents lepton flavor violation, by aligning the mass and weak eigenbases. For quarks, all the SM Yukawa couplings responsible for their observed masses and mixings arise at the renormalizable level. We perform fits to show that models in this class can explain $R_{K^{(*)}}$ and the other neutral current $B$ anomaly data if we introduce a heavy vectorlike quark to mediate the required quark flavor violation, while simultaneously satisfying other constraints from direct $Z^{\prime }$ searches at the LHC, $B_s$ meson mixing, a number of electroweak precision observables, and neutrino trident production. Within this symmetry-motivated framework of models, we find interesting implications for the flavor anomalies; notably, any axial couplings of the $Z^{\prime }$ to electrons and muons must be flavor universal, with the flavor universality violation arising solely from the vectorlike couplings. We also comment on the generation of neutrino masses in these models.

Searches for new astrophysical phenomena often involve several sources of nonrandom uncertainties that can lead to highly misleading results. Among these, model uncertainty arising from background mismodeling can dramatically compromise the sensitivity of the experiment under study. Specifically, overestimating the background distribution in the signal region increases the chances of missing new physics. Conversely, underestimating the background outside the signal region leads to an artificially enhanced sensitivity and a higher likelihood of claiming false discoveries. The aim of this work is to provide a unified statistical strategy to perform modeling, estimation, inference, and signal characterization under background mismodeling. The method proposed allows one to incorporate the (partial) scientific knowledge available on the background distribution and provides a data-updated version of it in a purely nonparametric fashion without requiring the specification of prior distributions on the unknown parameters. Applications in the context of dark matter searches and radio surveys show how the tools presented in this article can be used to incorporate nonstochastic uncertainty due to instrumental noise and to overcome violations of classical distributional assumptions in stacking experiments.

No-scale supergravity provides a successful framework for Starobinsky-like inflation models. Two classes of models can be distinguished depending on the identification of the inflaton with the volume modulus, $T$ (C models), or a matterlike field, $\varphi$ (WZ models). When supersymmetry is broken, the inflationary potential may be perturbed, placing restrictions on the form and scale of the supersymmetry breaking sector. We consider both types of inflationary models in the context of high-scale supersymmetry. We further distinguish between models in which the gravitino mass is below and above the inflationary scale. We examine the mass spectra of the inflationary sector. We also consider, in detail, mechanisms for leptogenesis for each model when a right-handed neutrino sector, used in the seesaw mechanism to generate neutrino masses, is employed. In the case of C models, reheating occurs via an inflaton decay to two Higgs bosons. However, there is a direct decay channel to the lightest right-handed neutrino which leads to nonthermal leptogenesis. In the case of WZ models, in order to achieve reheating, we associate the matterlike inflaton with one of the right-handed sneutrinos whose decay to the lightest right-handed neutrino simultaneously reheats the Universe and generates the baryon asymmetry through leptogenesis.

In the absence of a genuine solution to the sign problem, lattice studies at imaginary quark chemical potential are an important tool to constrain the QCD phase diagram. We calculate the values of the tricritical quark masses in the Roberge-Weiss plane, $\mu =𝚤\pi T/3$, which separate mass regions with chiral and deconfinement phase transitions from the intermediate region, for QCD with ${\mathrm{N}}_{\mathrm{f}}=2$ unimproved staggered quarks on ${\mathrm{N}}_{\tau }=6$ lattices. A quantitative measure for the quality of finite size scaling plots is developed, which significantly reduces the subjective judgement required for fitting. We observe that larger aspect ratios are necessary to unambiguously determine the order of the transition than at $\mu =0$. Comparing with previous results from ${\mathrm{N}}_{\tau }=4$ we find a $\sim 50\%$ reduction in the light tricritical pion mass. The heavy tricritical pion mass stays roughly the same, but is too heavy to be resolved on ${\mathrm{N}}_{\tau }=6$ lattices and thus equally afflicted with cut-off effects. Further comparison with other discretizations suggests that current cut-off effects on the light critical masses are likely to be larger than $\sim 100\%$, implying a drastic shrinking of the chiral first-order region to possibly zero.

We compute the next-to-leading order QCD and electroweak corrections to $Z$ and $W$ pole observables using the dimension-6 Standard Model effective field theory (SMEFT) and present numerical results that can easily be included in global fitting programs. Limits on SMEFT coefficient functions are presented at leading order and at next-to-leading order under several assumptions.

We use the path integral optimization approach of Caputa, Kundu, Miyaji, Takayanagi, and Watanabe to find the time slice of geometries dual to vacuum, primary, and thermal states in the $T\overline{T}$-deformed two-dimensional conformal field theories (CFTs). The obtained optimized geometries actually capture the entire bulk, which fits well with the integrability and expected UV completeness of $T\overline{T}$-deformed CFTs. When the deformation parameter is positive, these optimized solutions can be reinterpreted as geometries at finite bulk radius, in agreement with a previous proposal by McGough, Mezei, and Verlinde. We also calculate the holographic entanglement entropy and quantum state complexity for these solutions. We show that the complexity of formation for the thermofield double state in the deformed theory is UV finite, and it depends on the temperature.

The pure spinor formulation of superstring theory includes an interacting sector of central charge $c_{\lambda }=22$, which can be realized as a curved $\beta \gamma$ system on the cone over the orthogonal Grassmannian $O{G}^{+}(5,10)$. We find that the spectrum of the $\beta \gamma$ system organizes into representations of the $\mathfrak{g}={\mathfrak{e}}_6$ affine algebra at level $-3$, whose $\mathfrak{s}\mathfrak{o}(10{)}_{-3}\oplus \mathfrak{u}(1{)}_{-4}$ subalgebra encodes the rotational and ghost symmetries of the system. As a consequence, the pure spinor partition function decomposes as a sum of affine ${\mathfrak{e}}_6$ characters. We interpret this as an instance of a more general pattern of enhancements in curved $\beta \gamma$ systems, which also includes the cases $\mathfrak{g}=\mathfrak{s}\mathfrak{o}(8)$ and ${\mathfrak{e}}_7$, corresponding to target spaces that are cones over the complex Grassmannian $Gr(2,4)$ and the complex Cayley plane ${\mathbb{O}\mathbb{P}}^2$. We identify these curved $\beta \gamma$ systems with the chiral algebras of certain two-dimensional (2D) (0,2) conformal field theories arising from twisted compactification of 4D $\mathcal{N}=2$ superconformal field theories on $S^2$.

Gravity gradient is known as a serious systematic effect in atomic tests of the universality of free fall, where the initial central position and velocity of atoms need to be exactly controlled. In this paper, we study quantum free fall with high-order gravity gradients. It is shown that the cubic terms in the Newtonian potential shall generate a new phase shift in atom interferometers, which depends on the position and velocity uncertainties of the incident atoms. We further investigate the nonclassicality of free fall and show that, due to the cubic potential, the gravitational Wigner equation in phase space of position and velocity is different from the classical Liouville equation. There exists a mass-dependent correction in the dynamical equation regardless of initial state. Nevertheless, this is just a quantum mechanical effect of microparticles, which does not violate equivalence principle that inertia mass is equal to the gravitational mass.

We present a systematic procedure to compute complete, analytic form factors of gauge-invariant operators at loop level in pure Yang-Mills. We consider applications to operators of the form $\mathrm{Tr}{F}^n$ where $F$ is the gluon field strength. Our approach is based on an extension to form factors of the dimensional reconstruction technique, in conjunction with the six-dimensional spinor-helicity formalism and generalized unitarity. For form factors this technique requires the introduction of additional scalar operators, for which we provide a systematic prescription. We also discuss a generalization of dimensional reconstruction to any number of loops, both for amplitudes and form factors. Several novel results for one-loop minimal and nonminimal form factors of $\mathrm{Tr}{F}^n$ with $n>2$ are presented. Finally, we describe the Mathematica package spinorhelicity6d, which is tailored to handle six-dimensional quantities written in the spinor-helicity formalism.

We study the Kibble-Zurek mechanism in a 2d holographic $p$-wave superconductor model with a homogeneous source quench on the critical point. We derive, on general grounds, the scaling of the Kibble-Zurek time, which marks breaking-down of adiabaticity. It is expressed in terms of four critical exponents, including three static and one dynamical exponents. Via explicit calculations within a holographic model, we confirm the scaling of the Kibble-Zurek time and obtain the scaling functions in the quench process. We find the results are formally similar to a homogeneous quench in a higher dimensional holographic s-wave superconductor. The similarity is due to the special type of quench we take. We expect differences in the quench dynamics if the condition of homogeneous source and dominance of critical mode are relaxed.

We analyze the response of a spatially extended direction-dependent local quantum system, a detector, moving on the Rindler trajectory of uniform linear acceleration in Minkowski spacetime, and coupled linearly to a quantum scalar field. We consider two spatial profiles: i) a profile defined in the Fermi-Walker frame of an arbitrarily accelerating trajectory, generalizing the isotropic Lorentz-function profile introduced by Schlicht to include directional dependence, and ii) a profile defined only for a Rindler trajectory, utilizing the associated frame, and confined to a Rindler wedge, but again allowing arbitrary directional dependence. For i, we find that the transition rate on a Rindler trajectory is nonthermal, and dependent on the direction, but thermality is restored in the low and high frequency regimes, with a direction-dependent temperature, and also in the regime of high acceleration compared with the detector’s inverse size. For ii, the transition rate is isotropic, and thermal in the usual Unruh temperature. We attribute the nonthermality and anisotropy found in i to the leaking of the Lorentz-function profile past the Rindler horizon.

We demonstrate that the anisotropic stress energy supporting the Kiselev black hole can be mimicked by being split into a perfect fluid component plus either an electromagnetic component or a scalar field component, thereby quantifying the precise extent to which the Kiselev black hole fails to represent a perfect fluid spacetime. The perfect fluid component carries either an electric or a scalar charge, which then generates anisotropic electromagnetic or scalar fields. This in turn generates anisotropic contributions to the stress energy. These in turn induce forces that partially (in addition to the fluid pressure gradient) support the matter content against gravity. This decomposition is carried out both for the original one-component Kiselev black hole and for the generalized $N$-component Kiselev black holes. We also comment on the presence of energy condition violations (specifically for the null energy condition) for certain subclasses of Kiselev black holes.

We present a covariant approach to the problem of light beam propagation in a spacetime. We develop our considerations within the framework of classical geometric optics in general relativity. Using the concept of a screen surface orthogonal to the observer velocity and to the bundle of geodesics, we introduce covariant four-dimensional definitions for Sachs and Jacobi optical fields and for the area distance. Then we give relationships between them and derive their propagation equations together with initial conditions for these equations. Ultimately, for practical use, we transform the resulting formulas into the redshift-dependent form.