In this paper, triple neutral electroweak gauge boson production processes—viz. $\gamma \gamma \gamma$, $\gamma \gamma Z$, $\gamma ZZ$, and $ZZZ$ productions merged to one jet—are studied at the leading order in QCD in the context of the Randall-Sundrum (RS) model at the LHC with center-of-mass energy $\sqrt{S}=13\mathrm{TeV}$. The decay of $Z$ bosons into lepton pairs is considered. We present a selection of kinematical distributions matched to parton showers and show their deviation from the Standard Model results as a result of the RS model. The uncertainties as a result of the factorization and renormalization scales are also presented.

In the next generation of long-baseline neutrino oscillation experiments aiming to determine the charge-parity-violating phase ${\delta }_{CP}$ in the appearance channel, fine-grained time-projection chambers are expected to play an important role. In this paper, we analyze an influence of realistic detector capabilities on the ${\delta }_{CP}$ sensitivity for a setup similar to that of the Deep Underground Neutrino Experiment. We find that the effect of the missing energy carried out by undetected particles is sizable. Although the reconstructed neutrino energy can be corrected for the missing energy, the accuracy of such procedure has to exceed 20%, to avoid a sizable bias in the extracted ${\delta }_{CP}$ value.

We find a class of analytic solutions in open bosonic string field theory, parametrized by the chiral copy of higher spin algebra in ${\mathrm{AdS}}_3$. The solutions are expressed in terms of the generating function for the products of Bell polynomials in derivatives of bosonic space-time coordinates $X^m(z)$ of the open string, the form of which is determined in this work. The products of these polynomials form a natural operator algebra realizations of $w_{\infty }$ (area-preserving diffeomorphisms), enveloping algebra of SU(2) and higher spin algebra in ${\mathrm{AdS}}_3$. The class of string field theory solutions found can, in turn, be interpreted as the “enveloping of enveloping,” or the enveloping of ${\mathrm{AdS}}_3$ higher spin algebra. We also discuss the extensions of this class of solutions to superstring theory and their relations to higher spin algebras in higher space-time dimensions.

Localization of a spin-$1/2$ fermion on the braneworld is an important and interesting problem. It is well known that a five-dimensional free massless fermion $\mathrm{\Psi }$ minimally coupled to gravity cannot be localized on the Randall-Sundrum braneworld. In order to trap such a fermion, the coupling between the fermion and bulk scalar fields should be introduced. In this paper, localization and quasilocalization of a bulk fermion on the thick braneworld generated by two scalar fields (a kink scalar $\varphi$ and a dilaton scalar $\pi$) are investigated. Two types of couplings between the fermion and two scalars are considered. One coupling is the usual Yukawa coupling $-\eta \overline{\mathrm{\Psi }}\varphi \mathrm{\Psi }$ between the fermion and kink scalar, another one is $\lambda \overline{\mathrm{\Psi }}{\mathrm{\Gamma }}^M{\partial }_M\pi {\gamma }^5\mathrm{\Psi }$ between the fermion and dilaton scalar. The left-chiral fermion zero mode can be localized on the brane, and both the left- and right-chiral fermion massive Kaluza-Klein modes may be localized or quasilocalized. Hence the four-dimensional massless left-chiral fermion and massive Dirac fermions, whose lifetime is infinite or finite, can be obtained on the brane.

We study integrable open boundary conditions for $\mathfrak{d}(2,1;\alpha {)}^2$ and $\mathfrak{p}\mathfrak{s}\mathfrak{u}(1,1|2{)}^2$ spin-chains. Magnon excitations of these open spin-chains are mapped to massive excitations of type-IIB open superstrings ending on D-branes in the ${\mathrm{AdS}}_3\times S^3\times S^3\times S^1$ and ${\mathrm{AdS}}_3\times S^3\times T^4$ supergravity geometries with pure R-R flux. We derive reflection matrix solutions of the boundary Yang-Baxter equation which intertwine representations of a variety of boundary coideal subalgebras of the bulk Hopf superalgebra. Many of these integrable boundaries are matched to D1- and D5-brane maximal giant gravitons.

We analyze the Dirac equation for slow fermions coupled to linearized massive gravity above the Minkowski background and derive the effective low-energy gravitational potential. The obtained results can be used in terrestrial laboratories for the detection of gravitational waves and fluxes of massive gravitons emitted by cosmological objects. We also calculate the neutron spin precession within linearized massive gravity, which in principle can be measured by neutron interferometers.

Cosmic-ray muons and especially their secondaries break apart nuclei (“spallation”) and produce fast neutrons and beta-decay isotopes, which are backgrounds for low-energy experiments. In Super-Kamiokande, these beta decays are the dominant background in 6–18 MeV, relevant for solar neutrinos and the diffuse supernova neutrino background. In a previous paper, we showed that these spallation isotopes are produced primarily in showers, instead of in isolation. This explains an empirical spatial correlation between a peak in the muon Cherenkov light profile and the spallation decay, which Super-Kamiokande used to develop a new spallation cut. However, the muon light profiles that Super-Kamiokande measured are grossly inconsistent with shower physics. We show how to resolve this discrepancy and how to reconstruct accurate profiles of muons and their showers from their Cherenkov light. We propose a new spallation cut based on these improved profiles and quantify its effects. Our results can significantly benefit low-energy studies in Super-Kamiokande, and will be especially important for detectors at shallower depths, like the proposed Hyper-Kamiokande.

We study asymptotically free chiral gauge theories with an $\mathrm{SU}(N)$ gauge group and chiral fermions transforming according to the antisymmetric rank-$k$ tensor representation, $A_k\equiv [k{]}_N$, and the requisite number, $n_{\overline{F}}$, of copies of fermions in the conjugate fundamental representation, $\overline{F}\equiv {\overline{[1]}}_N$, to render the theories anomaly-free. We denote these as $A_k\overline{F}$ theories. We take $N\ge 2k+1$ so that $n_{\overline{F}}\ge 1$. The $A_2\overline{F}$ theories form an infinite family with $N\ge 5$, but we show that the $A_3\overline{F}$ and $A_4\overline{F}$ theories are only asymptotically free for $N$ in the respective ranges $7\le N\le 17$ and $9\le N\le 11$, and that there are no asymptotically free $A_k\overline{F}$ theories with $k\ge 5$. We investigate the types of ultraviolet to infrared evolution for these $A_k\overline{F}$ theories and find that, depending on $k$ and $N$, they may lead to a non-Abelian Coulomb phase, or may involve confinement with massless gauge-singlet composite fermions, bilinear fermion condensation with dynamical gauge and global symmetry breaking, or formation of multifermion condensates that preserve the gauge symmetry. We also show that there are no asymptotically free, anomaly-free $\mathrm{SU}(N)$ $S_k\overline{F}$ chiral gauge theories with $k\ge 3$, where $S_k$ denotes the rank-$k$ symmetric representation.

We study black hole solutions at first order in the Hartle-Thorne slow-rotation approximation in Horndeski gravity theories. We derive the equations of motion including also cases where the scalar depends linearly on time. In the Hartle-Thorne formalism, all first-order rotational corrections are described by a single frame-dragging function. We show that the frame-dragging function is exactly the same as in general relativity for all known black hole solutions in shift-symmetric Horndeski theories, with the exception of theories with a linear coupling to the Gauss-Bonnet invariant. Our results extend previous no-hair theorems for a broad class of Horndeski gravity theories.

We investigate how precisely the $CP$ nature of the 125 GeV Higgs boson $h$, parametrized by a scalar-pseudoscalar Higgs mixing angle ${\varphi }_{\tau }$, can be determined in $h\to {\tau }^{-}{\tau }^{+}$ decay with subsequent $\tau$-lepton decays to charged prongs at the Large Hadron Collider (LHC). We combine two methods in order to define an observable ${\phi }_{CP}^{*}$ which is sensitive to ${\varphi }_{\tau }$: We use the $\rho$-decay plane method for ${\tau }^{\mp }\to {\rho }^{\mp }$ and the impact parameter method for all other major $\tau$ decays. For estimating the precision with which ${\varphi }_{\tau }$ can be measured at the LHC (13 TeV) we take into account the ${\tau }^{-}{\tau }^{+}$ background from Drell-Yan production and perform a Monte Carlo simulation of measurement uncertainties on the ${\phi }_{CP}^{*}$ signal and background distributions. We obtain that the mixing angle ${\varphi }_{\tau }$ can be determined with an uncertainty of $\mathrm{\Delta }{\varphi }_{\tau }\simeq 15°$ (9°) at the LHC with an integrated luminosity of $150{\mathrm{fb}}^{-1}$ ($500{\mathrm{fb}}^{-1}$), and with $\mathrm{\Delta }{\varphi }_{\tau }\approx 4°$ with $3{\mathrm{ab}}^{-1}$. Future measurements of ${\varphi }_{\tau }$ yield direct information on whether or not there is an extended Higgs-boson sector with Higgs-sector $CP$ violation. We analyze this in the context of a number of two-Higgs-doublet extensions of the Standard Model, namely the so-called aligned model and conventional two-Higgs-doublet extensions with tree-level neutral flavor conservation.

The hadroproduction of prompt isolated photon pairs at high energies is studied in the framework of the parton Reggeization approach. The real part of the NLO corrections is computed (the ${\mathrm{NLO}}^{\star }$ approximation), and the procedure for the subtraction of double counting between real parton emissions in the hard-scattering matrix element and unintegrated parton distribution function is constructed for the amplitudes with Reggeized quarks in the initial state. The matrix element of the important next-to-next-to-leading-order subprocess $RR\to \gamma \gamma$ with full dependence on the transverse momenta of the initial-state Reggeized gluons is obtained. We compare obtained numerical results with diphoton spectra measured at the Tevatron and the LHC and find a good agreement of our predictions with experimental data at the high values of diphoton transverse momentum, $p_T$, and especially at the $p_T$ larger than the diphoton invariant mass, $M$. In this multi-Regge kinematics region, the NLO correction is strongly suppressed, demonstrating the self-consistency of the parton Reggeization approach.

By assuming that the ${\mathrm{\Lambda }}_c^{*}(2940)$ is a $p{D}^{*0}$ molecular state with spin-parity $J^P={\frac{1}{2}}^{+}$ and $J^P={\frac{1}{2}}^{-}$, the photoproduction of charmed ${\mathrm{\Lambda }}_c^{*}(2940)$ baryon in the $\gamma n\to D^{-}{\mathrm{\Lambda }}_c^{*}(2940{)}^{+}$ process is investigated with an effective Lagrangian approach. It is found that the contributions from the $t$-channel with $D^{*}$ exchange are dominant, while those from the $s$-channel with nucleon pole exchange give a sizeable contribution around the threshold. The contributions from the $u$-channel and contact term are very small. The total cross section of the $\gamma n\to D^{-}{\mathrm{\Lambda }}_c^{*}(2940{)}^{+}$ reaction is estimated, which indicate it is feasible to searching for the charmed ${\mathrm{\Lambda }}_c^{*}(2940)$ baryon at the COMPASS experiment.

In this paper, we studied the $\rho {\gamma }^{*}\to \pi$ and $\rho {\gamma }^{*}\to \rho$ transition processes and made the calculations for the $\rho \pi$ transition form factor $Q^4{F}_{\rho \pi }(Q^2)$ and the $\rho$-meson electromagnetic form factors, $F_{\mathrm{LL},\mathrm{LT},\mathrm{TT}}(Q^2)$ and $F_{1,2,3}(Q^2)$, by employing the perturbative QCD (PQCD) factorization approach. For the $\rho {\gamma }^{*}\to \pi$ transition, we found that the contribution to form factor $Q^4{F}_{\rho \pi }(Q^2)$ from the term proportional to the distribution amplitude combination ${\varphi }_{\rho }^T(x_1){\varphi }_{\pi }^P(x_2)$ is absolutely dominant, and the PQCD predictions for both the size and the $Q^2$-dependence of this form factor $Q^4{F}_{\rho \pi }(Q^2)$ agree well with those from the extended anti-de Sitter/QCD models or the light-cone QCD sum rule. For the $\rho {\gamma }^{*}\to \rho$ transition and in the region of $Q^2\ge 3{\mathrm{GeV}}^2$, furthermore, we found that the PQCD predictions for the magnitude and their $Q^2$-dependence of the $F_1(Q^2)$ and $F_2(Q^2)$ form factors agree well with those from the QCD sum rule, while the PQCD prediction for $F_3(Q^2)$ is much larger than the one from the QCD sum rule.

In this work we study the anomalous top quark-gluon couplings chromoelectric dipole moment and chromomagnetic dipole moment in a general two Higgs doublet model with $CP$ violation. We find that this model provides an important contribution from the $Y_{tt}$ Yukawa coupling that needs to be taken into account. The predictions for the chromomagnetic dipole moment and chromoelectric dipole moment obtained are $-0.03<\mathrm{\Delta }{\tilde{k}}_t<-0.005$ and $|\mathrm{\Delta }{\tilde{d}}_t|<0.005$, respectively.

In this paper we present a global fit of beyond the Standard Model (BSM) dimension-six operators relevant to the top quark sector to all currently available top production cross-section measurements, namely parton-level top-pair and single top production at the LHC and the Tevatron. Higher order QCD corrections are modeled using differential and global $K$-factors, and we use novel fast-fitting techniques developed in the context of Monte Carlo event generator tuning to perform the fit. This allows us to provide new, fully correlated and model-independent bounds on new physics effects in the top sector from the most current direct hadron-collider measurements in light of the involved theoretical and experimental systematics. As a by-product, our analysis constitutes a proof-of-principle that fast fitting of theory to data is possible in the top quark sector, and paves the way for a more detailed analysis including top quark decays, detector corrections and precision observables.

The effects of chiral imbalance and external magnetic field on pion superfluidity and color superconductivity are investigated in extended Nambu–Jona-Lasinio models. We take the Schwinger approach to treat the interaction between the charged pion condensate and magnetic field at finite isospin density and include simultaneously the chiral imbalance and magnetic field at finite baryon density. For the superfluidity, the chiral imbalance and magnetic field lead to catalysis and inverse catalysis effects, respectively. For the superconductivity, the chiral imbalance enhances the critical baryon density, and the magnetic field results in a de Haas–van Alphan oscillation on the phase transition line.

In general-relativistic perturbation theory, a point mass accelerates away from geodesic motion due to its gravitational self-force. Because the self-force is small, one can often approximate the motion as geodesic. However, it is well known that self-force effects accumulate over time, making the geodesic approximation fail on long time scales. It is less well known that this failure at large times translates to a failure at large distances as well. At second perturbative order, two large-distance pathologies arise: spurious secular growth and infrared-divergent retarded integrals. Both stand in the way of practical computations of second-order self-force effects. Utilizing a simple flat-space scalar toy model, I develop methods to overcome these obstacles. The secular growth is tamed with a multiscale expansion that captures the system’s slow evolution. The divergent integrals are eliminated by matching to the correct retarded solution at large distances. I also show how to extract conservative self-force effects by taking local-in-time “snapshots” of the global solution. These methods are readily adaptable to the physically relevant case of a point mass orbiting a black hole.

Four-dimensional static Schwarzschild-like solutions obtained in [H. Maeda and N. Dadhich, Phys. Rev. D 74, 021501(R) (2006).H. Maeda and N. Dadhich, Phys. Rev. D 75, 044007 (2007).N. Dadhich and H. Maeda, Int. J. Mod. Phys. D 17, 513 (2008).A. Molina and N. Dadhich, Int. J. Mod. Phys. D 18, 599 (2009).] in the frames of the Einstein-Gauss-Bonnet gravity at the Kaluza-Klein split are analyzed. In such models matter is created by auxiliary dimensions. The main goal of our work is to check that these solutions are physically sensible, and to examine their characteristics, which could be observable. A noncontradictive definition of a total mass (energy) is given. Study of the perturbed equations demonstrates a possibility of their stability under linear perturbations. Depending on the combination of the parameters, black hole-like objects with one or two horizons or naked singularity are described in detail. Stable orbits of test particles around these black holes are presented. We show the exotic thermodynamical properties of the solution, in which the Hawking evaporation law has the behavior opposite to the usual one in general relativity. Unfortunately, current astronomical data do not allow one to distinguish special observable evidences, which we find for the solutions under consideration, from usual Schwarzschild ones.

Stationary, axially symmetric Brans-Dicke-Maxwell solutions are reexamined in the framework of the Brans-Dicke (BD) theory. We see that, employing a particular parametrization of the standard axially symmetric metric simplifies the procedure of obtaining the Ernst equations for axially symmetric electrovacuum spacetimes for this theory. This analysis also permits us to construct a two parameter extension in both Jordan and Einstein frames of an old solution generating technique frequently used to construct axially symmetric solutions for BD theory from a seed solution of general relativity. As applications of this technique, several known and new solutions are constructed including a general axially symmetric BD-Maxwell solution of Plebanski-Demianski with vanishing cosmological constant, i.e., the Kinnersley solution and general magnetized Kerr-Newman–type solutions. Some physical properties and the circular motion of test particles for a particular subclass of Kinnersley solution, i.e., a Kerr-Newman-NUT–type solution for BD theory, are also investigated in some detail.