We extend the study of nuclear dependence of the transverse momentum dependent parton distribution functions and azimuthal asymmetries to semi-inclusive deep inelastic scattering (SIDIS) off polarized nuclear targets. We show that azimuthal asymmetries are suppressed for SIDIS off a polarized nuclear target relative to that off a polarized nucleon due to multiple scattering inside the nucleus. Using the value of transport parameter inside large nuclei extracted from jet quenching analyses in SIDIS off nuclear targets, we also present a numerical estimate of the nuclear suppression of the azimuthal asymmetry that might be useful to guide the future experimental studies of SIDIS off polarized nuclear targets.

Planck scale lepton number violation is an interesting and natural possibility to explain nonzero neutrino masses. We consider such operators in the context of Randall-Sundrum (RS1) scenarios. Implementation of this scenario with a single Higgs localized on the IR brane (standard RS1) is not phenomenologically viable as they lead to inconsistencies in the charged lepton mass fits. In this paper we propose a setup with two Higgs doublets. We present a detailed numerical analysis of the fits to fermion masses and mixing angles. This model solves the issues regarding the fermion mass fits but solutions with consistent electroweak symmetry breaking are highly fine-tuned. A simple resolution is to consider supersymmetry in the bulk and a detailed discussion of which is provided. Constraints from flavor are found to be strong and minimal flavor violation (MFV) is imposed to alleviate them.

Recently the ATLAS and CMS Collaborations have reported significant events that are attributed to the neutral Higgs boson with mass around 125 GeV. In this work, we investigate the signals of the Higgs boson decay channels $h\to \gamma \gamma$, $h\to V{V}^{*}(V=Z,W)$, and $h\to f\overline{f}(f=b,\tau )$ in the $\mu$ from $\nu$ supersymmetric standard model ($\mu \nu \mathrm{SSM}$). In the numerical results, we show the light stop and stau effects on the signal strengths for the 125 GeV Higgs boson decay channels in the $\mu \nu$SSM, which can account for the updated experimental data on Higgs.

We perform an isospin analysis of $B$ decays to two pseudoscalars. The analysis extracts appropriate Cabbibo-Kobayashi-Maskawa matrix elements and short distance loop factors to allow for comparison of nonperturbative QCD effects in the reduced matrix elements of the amplitudes. In decays where penguin diagrams compete with tree-level diagrams we find that the reduced matrix elements of the penguin diagrams, which are singlets or doublets under isospin, are significantly enhanced compared with the triplet and fourplet contributions of the weak Hamiltonian. This similarity to the $\mathrm{\Delta }I=\frac{1}{2}$ rule in $K\to \pi \pi$ decays suggests that, more generally, processes mediated by Hamiltonians in lower-dimensional isospin representations see enhancement over higher-dimensional ones in QCD.

We show that the existence of new, light gauge interactions coupled to Standard Model (SM) neutrinos gives rise to an abundance of sterile neutrinos through the sterile neutrinos’ mixing with the SM. Specifically, in the mass range of MeV–GeV and coupling of $g^{\prime }\sim 10^{-6}$–$10^{-3}$, the decay of this new vector boson in the early Universe produces a sufficient quantity of sterile neutrinos to account for the observed dark matter abundance. Interestingly, this can be achieved within a natural extension of the SM gauge group, such as a gauged $L_{\mu }-L_{\tau }$ number, without any tree-level coupling between the new vector boson and the sterile neutrino states. Such new leptonic interactions might also be at the origin of the well-known discrepancy associated with the anomalous magnetic moment of the muon.

The recent high-statistics high-energy atmospheric neutrino data collected by IceCube open a new window to probe new physics scenarios that are suppressed in lower-energy neutrino experiments. In this paper we analyze the IceCube atmospheric neutrino data to constrain the violation of equivalence principle (VEP) in the framework of three neutrinos with nonuniversal gravitational couplings. In this scenario the effect of the VEP on neutrino oscillation probabilities can be parametrized by two parameters, $\mathrm{\Delta }{\gamma }_{21}\equiv {\gamma }_2-{\gamma }_1$ and $\mathrm{\Delta }{\gamma }_{31}\equiv {\gamma }_3-{\gamma }_1$, where ${\gamma }_i$’s denote the coupling of neutrino mass eigenstates to the gravitational field. By analyzing the latest muon-tracks data sets of IceCube-40 and IceCube-79, besides providing the two-dimensional allowed regions in the $(\varphi \mathrm{\Delta }{\gamma }_{21},\varphi \mathrm{\Delta }{\gamma }_{31})$ plane, we obtain the upper limits $|\varphi \mathrm{\Delta }{\gamma }_{21}|<9.1\times {10}^{-27}$ (at 90% C.L.), which improves the previous limit by $\sim 4$ orders of magnitude, and $|\varphi \mathrm{\Delta }{\gamma }_{31}|\lesssim 6\times {10}^{-27}$ (at 90% C.L.), which improves the current limit by $\sim 1$ order of magnitude. Also we discuss in detail and analytically the effect of the VEP on neutrino oscillation probabilities.

We compute—at finite quark chemical potentials—the color screening of cold quark matter at the one-loop level, comparing the normal, BCS-paired ${\mathrm{U}(1)}_{\text{em}}$ (or Higgs) phase and a singlet phase with color-singlet condensate near the Fermi surface. The latter phase is computed using the example of two-color QCD with a color-singlet diquark condensate. In contrast to the normal and Higgs phases, neither electric nor magnetic screening masses appear in the singlet phase. The absence of a magnetic mass, within a perturbative framework, is a consequence of the proper treatment of gauge invariance. While at large momenta the gluon self-energies approach those in the normal phase, the medium contributions to the infrared region below a scale of the mass gap are substantially suppressed. Infrared gluons at low quark density in the singlet phase appear protected from medium effects, unless the quark-gluon vertices are significantly enhanced in the infrared.

The $P$-wave and $S$-wave heavy-light mesons and their charge conjugates, i.e., $D_1(2420)\overline{D}+\mathrm{c}.\mathrm{c}.$, $D_1(2420){\overline{D}}^{*}+\mathrm{c}.\mathrm{c}.$, and $D_2(2460){\overline{D}}^{*}+\mathrm{c}.\mathrm{c}.$, can couple to states with vector quantum number $J^{PC}=1^{--}$ and exotic quantum number $J^{PC}=1^{-+}$ in a relative $S$ wave. Near threshold, the heavy-light meson pair may form hadronic molecules due to the strong $S$-wave coupling, and the mysterious vector state $Y(4260)$ could be such a state of the $D_1(2420)\overline{D}+\mathrm{c}.\mathrm{c}.$ molecule. This implies the possible existence of its conjugate partner made of the same heavy-light mesons but with exotic quantum number $J^{PC}=1^{-+}$. We evaluate the production rate of such exotic hadronic molecules and propose a direct experimental search for them in $e^{+}{e}^{-}$ annihilation. Confirmation of such exotic states in experiment will certainly deepen our insights into strong QCD and the arrangement of multiquark degrees of freedom.

We study the holographic entanglement entropy of nonlocal field theories at both extremality and finite temperature. The gravity duals, constructed by Nozaki et al. [J. High Energy Phys. 10 (2012) 193], are characterized by a parameter $w$. Both the zero-temperature backgrounds and the finite-temperature counterparts are exact solutions of Einstein-Maxwell-dilaton theory. For the extremal case we consider the examples where the entangling regions are a strip and a sphere. We find that the leading-order behavior of the entanglement entropy always exhibits a volume law when the size of the entangling region is sufficiently small. We also clarify the condition under which the next-to-leading-order result is universal. For the finite-temperature case we obtain analytic expressions in both the high-temperature and low-temperature limits. In the former case the leading-order result approaches the thermal entropy, while the finite contribution to the entanglement entropy at extremality can be extracted by taking the zero-temperature limit in the latter case. Moreover, we observe some peculiar properties of the holographic entanglement entropy when $w=1$.

Using a semiparametric approach based on the fourth-order Edgeworth expansion for the unknown signal distribution, we derive an explicit expression for the likelihood detection statistic in the presence of a non-normally distributed gravitational wave stochastic background. Numerical likelihood maximization exercises based on Monte Carlo simulations for a set of large tail symmetric non-Gaussian distributions suggest that the fourth cumulant of the signal distribution can be estimated with reasonable precision when the ratio between the signal and the noise variances is larger than 0.01. The estimation of higher-order cumulants of the observed gravitational wave signal distribution is expected to provide additional constraints on astrophysical and cosmological models.

Recent measurements from the BICEP2 cosmic microwave background polarization experiment indicate the presence of primordial gravitational waves with surprisingly large amplitude. If these results are confirmed, they point to a discrepancy with temperature anisotropy power spectrum measurements and suggest that extensions to the standard cosmological model may be required to resolve the discrepancy. One intriguing extension is an anticorrelation between tensors and scalars to naturally suppress the temperature power. Here I examine this possibility and show that such a suppression is not possible in the presence of a general form of anticorrelation.

We investigate $SU(3)$ gauge theories in four dimensions with $N_f$ fundamental fermions on a lattice using the Wilson fermion. Clarifying the vacuum structure in terms of Polyakov loops in spatial directions and properties of temporal propagators using a new method that we call “local analysis,” we conjecture that the “conformal region” exists together with the confining region and the deconfining region in the phase structure parametrized by $\beta$ and $K$, both in the cases of the large $N_f$ QCD within the conformal window (referred as conformal QCD) with an IR cutoff and small $N_f$ QCD at $T/T_c>1$ with $T_c$ being the chiral transition temperature (referred to as high-temperature QCD). Our numerical simulation on a lattice of the size $16^3\times 64$ shows the following evidence of the conjecture. In the conformal region, we find that the vacuum is the nontrivial $Z(3)$ twisted vacuum modified by nonperturbative effects and that temporal propagators of mesons behave at large $t$ as a power-law-corrected Yukawa-type decaying form. The transition from the conformal region to the deconfining region or the confining region is a sharp transition between different vacua, and therefore, it suggests a first-order transition both in conformal QCD and high-temperature QCD. To confirm the conjecture and distinguish it from the possibility of crossover phenomena, we need to take the continuum/thermodynamic limit, which we do not attempt in this work. Within our fixed-lattice simulation, we find that there is a precise correspondence between conformal QCD and high-temperature QCD in the temporal propagators under the change of the parameters $N_f$ and $T/T_c$, respectively: one boundary is close to meson states, and the other is close to free quark states. In particular, conformal QCD with $N_f=7$ corresponds to high-temperature QCD with $N_f=2$ at $T\sim 2T_c$, both of which are in close relation to a meson unparticle model. From this, we estimate the anomalous mass dimension ${\gamma }^{*}=1.2(1)$ for $N_f=7$. We also show that the asymptotic state in the limit $T/T_c\to \infty$ is a free quark state in the $Z(3)$ twisted vacuum. The approach to a free quark state is very slow; even at $T/T_c\sim 10^5$, the state is affected by nonperturbative effects. This is possibly connected with the slow approach of the free energy to the Stefan-Boltzmann ideal gas limit.

We present the full $\mathcal{O}({\alpha }_s)$ supersymmetric QCD corrections for gaugino annihilation and coannihilation into light and heavy quarks in the minimal supersymmetric standard model (MSSM). We demonstrate that these channels are phenomenologically relevant within the so-called phenomenological MSSM. We discuss selected technical details such as the dipole subtraction method in the case of light quarks and the treatment of the bottom quark mass and Yukawa coupling. Numerical results for the (co)annihilation cross sections and the predicted neutralino relic density are presented. We show that the impact of including the radiative corrections on the cosmologically preferred region of the parameter space is larger than the current experimental uncertainty from Planck data.

In this paper we present the details of our previous work on exact solutions in second-order conformal hydrodynamics together with a number of new solutions found by mapping Minkowski space onto various curved space-times, such as anti–de Sitter space and hyperbolic space. We analytically show how the solutions of ideal hydrodynamics are modified by the second-order effects including vorticity. We also find novel boost-invariant exact solutions which exist only in second-order hydrodynamics and have an unusual dependence on the proper time.

The ArgoNeuT collaboration presents measurements of inclusive muon neutrino and antineutrino charged current differential cross sections on argon in the Fermilab NuMI beam operating in the low energy antineutrino mode. The results are reported in terms of outgoing muon angle and momentum at a mean neutrino energy of 9.6 GeV (neutrinos) and 3.6 GeV (antineutrinos), in the range $0°<{\theta }_{\mu }<36°$ and $0<p_{\mu }<25\mathrm{GeV}/c$, for both neutrinos and antineutrinos.

This work deals with braneworld scenarios with generalized teleparallel gravity. We extend a recent investigation, where the model studied was described by $F(T)=T+k{T}^n$. In the current study, we introduce the first-order formalism to find analytical solutions for models that include a scalar field with standard and generalized dynamics. In particular, we describe the interesting case in which the brane splits, due to the parameters that control deviation from the standard model.

We calculate the self-force of a constantly accelerating electric dipole, showing, in particular, that classical electromagnetism does not predict that an electric dipole could self-accelerate, nor could it levitate in a gravitational field. We also resolve a paradox concerning the inertial mass of a longitudinally accelerating dipole, showing that the combined system of dipole plus field can be assigned a well-defined energy-momentum four-vector, so that the principle of relativity is satisfied. We then present some general features of electromagnetic phenomena in a reference frame described by the Rindler metric, showing in particular that an observer fixed in a gravitational field described everywhere by the Rindler metric will find any charged object supported in the gravitational field to possess an electromagnetic self-force equal to that observed by an inertial observer relative to which the body undergoes rigid hyperbolic motion. It follows that the principle of equivalence is satisfied by these systems.

Four-dimensional, asymptotically flat spacetimes with an ergoregion but no horizon have been shown to be linearly unstable against a superradiant-triggered mechanism. This result has wide implications in the search for astrophysically viable alternatives to black holes, but also in the understanding of black holes and Hawking evaporation. Here we investigate this instability in detail for a particular setup that can be realized in the laboratory: the hydrodynamic vortex, an effective geometry for sound waves, with ergoregion and without an event horizon.

We consider the properties of solutions in the bigravity theory for a wide class of models, which are parametrized by two parameters ${\alpha }_3$ and ${\alpha }_4$. Assuming that two metric tensors $g_{\mu \nu }$ and $f_{\mu \nu }$ satisfy the condition $f_{\mu \nu }=C^2{g}_{\mu \nu }$, where $C$ is a constant, we investigate the conditions for the parameters so that the solutions with $C\ne 1$ could exist. We also discuss the magnitude and the sign of corresponding cosmological constants. For the black hole solution, we consider the black hole entropy to which the massive spin-2 field contributes. In order to obtain the black hole entropy, we take an approach where we use the Virasoro algebra and the central charge corresponding to the surface term in the action.