A complete numerical calculation of the temperature anisotropies and the polarization of the cosmic microwave background is presented for a nonzero cross correlation of a stochastic magnetic field with the primordial curvature perturbation. Such a cross correlation results, for example, if the magnetic field is generated during inflation by coupling electrodynamics to a scalar field that is identified with the curvaton. For a nearly scale-invariant magnetic field of 1 nG it is found that the contribution due to the cross correlation dominates over that of the pure magnetic mode. A similar behavior on large scales is found for the linear matter power spectrum.

Recently, a general principle, called $c$-extremization, which determines the exact $R$ symmetry of two-dimensional conformal field theories with $\mathcal{N}=(0,2)$ supersymmetry, was identified. In this work we show that the supergravity dual corresponds to the extremization of the $T$ tensor of $\mathcal{N}=2$ gauged supergravity in three dimensions. To support this claim, we demonstrate that the expected central charge of conformal field theories arising from twisted compactifications of four-dimensional $\mathcal{N}=4$ Super-Yang-Mills on Riemann surfaces, whose gravity dual is a reduction of five-dimensional $U(1{)}^3$ gauged supergravity, is recovered in the three-dimensional framework.

Breaking of isotropy and Lorentz boost invariance in the dynamics of second-generation leptons would lead to direction-dependent changes in the lifetimes of charged pions. This would make the intensity of a neutrino beam produced via pion decay a function of the beam orientation. The experimental signature of this phenomenon—sidereal variations in the event rate at a downstream neutrino detector—has already been studied, in searches for Lorentz-violating neutrino oscillations. Existing analyses of MINOS near detector data can be used to constrain the flavor-diagonal Lorentz violation coefficients affecting muon neutrino speeds at roughly the ${10}^{-5}$ level.

In the context of warped extra dimensional models with all fields propagating in the bulk, we address the phenomenology of a bulk scalar Higgs boson, and calculate its production cross section at the LHC as well as its tree-level effects on mediating flavor changing neutral currents. We perform the calculations based on two different approaches. First, we compute our predictions analytically by considering all the degrees of freedom emerging from the dimensional reduction [the infinite tower of Kaluza Klein modes (KK)]. In the second approach, we perform our calculations numerically by considering only the effects caused by the first few KK modes, present in the 4-dimensional effective theory. In the case of a Higgs leaking far from the brane, both approaches give the same predictions as the effects of the heavier KK modes decouple. However, as the Higgs boson is pushed toward the TeV brane, the two approaches seem to be equivalent only when one includes heavier and heavier degrees of freedom (which do not seem to decouple). To reconcile these results it is necessary to introduce higher dimension operators which essentially encode the effects of integrating out the heavy KK modes and dress the brane Higgs so that it looks just like a bulk Higgs. However, in the brane Higgs limit, it is not possible to predict if there will be enhancement or suppression in the Higgs production rate since the corrections depend on the phases of higher dimension operators.

Pair production of light top squarks at the 8-TeV LHC can be used to probe the gaugino-Higgsino sector of the minimal supersymmetric standard model. The case where the lightest neutralino is a mixture of bino and Higgsino, satisfying the thermal dark matter relic density, is investigated. In such a scenario, the lightest top squark decays mostly into (i) a top quark plus the second or third lightest neutralino, and (ii) a bottom quark plus the lightest chargino, instead of a decay scenario of the lightest top squark into a top quark and the lightest neutralino. Final states with $\ge 2$ jets, dileptons, and missing energy are expected in a subsequent decay of the second or third lightest neutralinos into the lightest neutralino via an intermediate slepton (“light sleptons” case) or $Z$ boson (“heavy sleptons” case). The opposite-sign same flavor dilepton mass distribution after subtracting the opposite-sign different flavor distribution shows a clear edge in the case of light sleptons. The significance for discovering such a scenario is calculated with optimized cuts in both light and heavy sleptons cases.

We propose a simple model where dark matter (DM) carries top flavor and couples to the Standard Model through the top quark within a framework of minimal flavor violation. Top-flavored DM can explain the anomalous top forward-backward asymmetry observed at the Tevatron, while remaining consistent with other top observables at colliders. By virtue of its large coupling to the top, DM acquires a sizable loop coupling to the $Z$ boson, and the relic density is set by annihilation through the $Z$. We also discuss constraints from current direct detection searches, emphasizing the role of spin-dependent searches to probe this scenario.

We discuss the realization of a two Higgs doublets model in the framework of a six-dimensional gauge-Higgs unification model with a simple Lie group $G_M$. Two Higgs $SU(2{)}_L$ doublets can emerge at the low energy effective theory, and the quartic coupling terms in the scalar potential, which are essential for the electroweak symmetry breaking, are now $G_M$ gauge invariant and permissive. A realistic two Higgs doublets model can possibly be obtained only when two of the root vectors associated with the would-be Higgs doublets and the root vector for $SU(2{)}_L$ form an isosceles triangle with a vertex angle either of $\pi /3$, $\pi /2$, or $2\pi /3$. Moreover, depending on $G_M$, the scalar potential of the resulting two Higgs doublets model can admit only a few limited forms. The mass spectrum of the physical Higgs and the weak mixing angle are briefly discussed.

We verify that $SU(N{)}_{\mathrm{TC}}\otimes SU(3{)}_L\otimes U(1{)}_X$ models, where the gauge symmetry breaking is totally dynamical and promoted by the non-Abelian technicolor group and the strong Abelian interactions, are quite constrained by the LHC data. The theory contains a $T$ quark self-energy involving the mixing between the neutral gauge bosons, which introduces the coupling between the light and heavy composite scalar bosons of the model. We determine the lightest scalar boson mass for these models from an effective action for composite operators, assuming details about the dynamics of the strong interaction theories. Comparing the value of this mass with the ATLAS and CMS observation of a new boson with a mass $M_{\varphi }\sim 125\mathrm{GeV}$ and considering the lower bound determined by the LHC Collaboration on the heavy neutral gauge boson $(Z^{\prime })$ present in these models, we can establish constraints on the possible models. For example, if $SU(N{)}_{\mathrm{TC}}\equiv SU(2{)}_{\mathrm{TC}}$, with technifermions in the fundamental representation, the model barely survives the confrontation with the LHC data.

We calculate the energies of quarkonium bound states in the presence of a medium of nonzero isospin density using lattice QCD. The medium, created using a canonical (fixed isospin charge) approach, induces a reduction of the quarkonium energies. As the isospin density increases, the energy shifts first increase and then saturate. The saturation occurs at an isospin density close to that where previously a qualitative change in the behavior of the energy density of the medium has been observed, which was conjectured to correspond to a transition from a pion gas to a Bose-Einstein condensed phase. The reduction of the quarkonium energies becomes more pronounced as the heavy-quark mass is decreased, similar to the behavior seen in two-color QCD at nonzero quark chemical potential. In the process of our analysis, the ${\eta }_b\mathrm{\text{−}}\pi$ and ${\rm Y}\mathrm{\text{−}}\pi$ scattering phase shifts are determined at low momentum. An interpolation of the scattering lengths to the physical pion mass gives $a_{{\eta }_b,\pi }=0.0025(8)(6)\mathrm{fm}$ and $a_{{\rm Y},\pi }=0.0030(9)(7)\mathrm{fm}$.

We present three new sets of next-to-leading order parton distribution functions (PDFs) determined by global fits to a wide variety of data for hard scattering processes. The analysis includes target mass and higher twist corrections needed for the description of deep inelastic scattering data at large $x$ and low $Q^2$, and nuclear corrections for deuterium targets. The PDF sets correspond to three different models for the nuclear effects, and provide a more realistic uncertainty range for the $d$ quark PDF, in particular, compared with previous fits. We describe the PDF error sets for each choice of the nuclear corrections, and provide a user interface for utilizing the distributions.

This paper completes the study of the next-to-leading-order QCD corrections to massive color-octet vector boson production at the LHC and Tevatron. The massive color-octet vector bosons are generically referred to as colorons. Building on our previous calculation of quark-initiated coloron production at next-to-leading order, we use the pinch technique to investigate coloron production via gluon fusion. We demonstrate that this one-loop production amplitude is finite and find that its numerical contribution to coloron production is typically 4 orders of magnitude smaller than the contribution from quark annihilation. Coloron production via gluon fusion is therefore relevant only if the colorons are (nearly) fermiophobic. We then present extensive plots and tables of our full results for next-to-leading-order coloron production at the Tevatron and the LHC.

In this work, we introduce the hadronic loop contribution to explain the anomalous radiative transitions between $h_b(nP)$ and ${\eta }_b(mS)$, which was recently observed by the Belle Collaboration. Our calculation shows that the hadronic loop mechanism associated with these known decay mechanisms can explain why there exist anomalous radiative transitions between $h_b(nP)$ and ${\eta }_b(mS)$. This study deepens our understanding of the decay mechanism of higher bottomonium radiative decays.

Comparisons of experimental data with theoretical predictions for collider processes containing hadronic jets rely on shower Monte Carlo event generators to include corrections to perturbative calculations from hadronization, parton showering, and multiple parton collisions. We examine current treatments of these corrections and propose alternative methods to take into account nonperturbative effects and parton showering in the context of next-to-leading-order event generators. We point out sizable parton-showering corrections to jet transverse energy spectra at high rapidity and discuss kinematic shifts in longitudinal momentum distributions from initial state showering in the case both of jet production and of heavy mass production at the Large Hadron Collider.

We use results of fits to the OPAL spectral data, obtained from nonstrange hadronic $\tau$ decays, to evaluate the difference between the vector and axial current correlators, ${\Pi }_{V-A}(Q^2)$. The behavior of ${\Pi }_{V-A}(Q^2)$ near Euclidean momentum $Q^2=0$ is used to determine the effective low-energy constants $L_{10}^{\mathrm{eff}}$ and $C_{87}^{\mathrm{eff}}$ related to the renormalized low-energy constants $L_{10}^r$ and $C_{87}^r$ in the chiral Lagrangian. We also investigate how well two-loop chiral perturbation theory describes ${\Pi }_{V-A}(Q^2)$ as a function of $Q^2$. This is the first determination of $L_{10}^{\mathrm{eff}}$ and $C_{87}^{\mathrm{eff}}$ to employ a fully self-consistent model for the violations of quark-hadron duality in both the vector and axial channels. We also discuss the values of the coefficients $C_{6,V-A}$ and $C_{8,V-A}$ governing the dimension-six and -eight contributions to the operator product expansion representation of ${\Pi }_{V-A}(Q^2)$.

We study whether a dominant contribution to neutrinoless double beta decay coming from extra heavy degrees of freedom, introduced to generate the light neutrino masses, can dominate over the light neutrino contribution. It has been shown that this may occur at tree level if the light neutrino contribution partially cancels out. Here we focus on this case, specifically in the context of type-I seesaw models, paying special attention to the one-loop corrections to light neutrino masses, their contribution to the process and correlation with the heavy sector. We perform a general analysis without restricting the study to any particular region of the parameter space, although interesting limits associated with inverse and extended seesawlike models are discussed in more detail. It turns out that the heavy neutrinos can dominate the process only in those limits. For the inverse seesaw limit, we find a very constrained allowed region of the parameter space, with heavy neutrino masses around 5 GeV. The extended seesaw case allows for a larger region, but in general, a hierarchical spectrum of heavy neutrinos with masses above and below $\sim 100\mathrm{MeV}$ is required.

We show that, leaving aside accelerated cosmic expansion, all experimental data in high energy physics that are commonly agreed to require physics beyond the Standard Model can be explained when completing the model by three right-handed neutrinos that can be searched for using present-day experimental techniques. The model that realizes this scenario is known as the Neutrino Minimal Standard Model ($\nu \mathrm{MSM}$). In this article we give a comprehensive summary of all known constraints in the $\nu \mathrm{MSM}$, along with a pedagogical introduction to the model. We present the first complete quantitative study of the parameter space of the model where no physics beyond the $\nu \mathrm{MSM}$ is needed to simultaneously explain neutrino oscillations, dark matter, and the baryon asymmetry of the Universe. The key new point of our analysis is leptogenesis after sphaleron freeze-out, which leads to resonant dark matter production, thus evading the constraints on sterile neutrino dark matter from structure formation and x-ray searches. This requires one to track the time evolution of left- and right-handed neutrino abundances from hot big bang initial conditions down to temperatures below the QCD scale. We find that the interplay of resonant amplifications, $CP$-violating flavor oscillations, scatterings, and decays leads to a number of previously unknown constraints on the sterile neutrino properties. We furthermore reanalyze bounds from past collider experiments and big bang nucleosynthesis in the face of recent evidence for a nonzero neutrino mixing angle ${\theta }_{13}$. We combine all our results with existing constraints on dark matter properties from astrophysics and cosmology. Our results provide a guideline for future experimental searches for sterile neutrinos. A summary of the constraints on sterile neutrino masses and mixings has appeared in Canetti et al. [Phys. Rev. Lett. 110, 061801 (2013)]. In this article we provide all details of our calculations and give constraints on other model parameters.

The process $e^{+}{e}^{-}\to p\overline{p}\gamma$ is studied using $469{\mathrm{fb}}^{-1}$ of integrated luminosity collected with the BABAR detector at the SLAC National Accelerator Laboratory, at an $e^{+}{e}^{-}$ center-of-mass energy of 10.6 GeV. From the analysis of the $p\overline{p}$ invariant mass spectrum, the energy dependence of the cross section for $e^{+}{e}^{-}\to p\overline{p}$ is measured from threshold to 4.5 GeV. The energy dependence of the ratio of electric and magnetic form factors, $|G_E/G_M|$, and the asymmetry in the proton angular distribution are measured for $p\overline{p}$ masses below 3 GeV. The branching fractions for the decays $J/\psi \to p\overline{p}$ and $\psi (2S)\to p\overline{p}$ are also determined.

We study the decay ${\overline{B}}^0\to {\Lambda }_c^{+}\overline{p}{\pi }^{+}{\pi }^{-}$, reconstructing the ${\Lambda }_c^{+}$ baryon in the $p{K}^{-}{\pi }^{+}$ mode, using a data sample of $467\times {10}^6$ $B\overline{B}$ pairs collected with the BABAR detector at the PEP-II storage rings at SLAC. We measure branching fractions for decays with intermediate ${\Sigma }_c$ baryons to be $\mathcal{B}[{\overline{B}}^0\to {\Sigma }_c(2455{)}^{++}\overline{p}{\pi }^{-}]=(21.3\pm 1.0\pm 1.0\pm 5.5)\times {10}^{-5}$, $\mathcal{B}[{\overline{B}}^0\to {\Sigma }_c(2520{)}^{++}\overline{p}{\pi }^{-}]=(11.5\pm 1.0\pm 0.5\pm 3.0)\times {10}^{-5}$, $\mathcal{B}[{\overline{B}}^0\to {\Sigma }_c(2455{)}^0\overline{p}{\pi }^{+}]=(9.1\pm 0.7\pm 0.4\pm 2.4)\times {10}^{-5}$, and $\mathcal{B}[{\overline{B}}^0\to {\Sigma }_c(2520{)}^0\overline{p}{\pi }^{+}]=(2.2\pm 0.7\pm 0.1\pm 0.6)\times {10}^{-5}$, where the uncertainties are statistical, systematic, and due to the uncertainty on the ${\Lambda }_c^{+}\to p{K}^{-}{\pi }^{+}$ branching fraction, respectively. For decays without ${\Sigma }_c(2455)$ or ${\Sigma }_c(2520)$ resonances, we measure $\mathcal{B}[{\overline{B}}^0\to {\Lambda }_c^{+}\overline{p}{\pi }^{+}{\pi }^{-}{]}_{\mathrm{non}\mathrm{\text{−}}{\Sigma }_c}=(79\pm 4\pm 4\pm 20)\times {10}^{-5}$. The total branching fraction is determined to be $\mathcal{B}[{\overline{B}}^0\to {\Lambda }_c^{+}\overline{p}{\pi }^{+}{\pi }^{-}{]}_{\mathrm{total}}=(123\pm 5\pm 7\pm 32)\times {10}^{-5}$. We examine multibody mass combinations in the resonant three-particle ${\Sigma }_c\overline{p}\pi$ final states and in the four-particle ${\Lambda }_c^{+}\overline{p}{\pi }^{+}{\pi }^{-}$ final state, and observe different characteristics for the $\overline{p}\pi$ combination in neutral versus doubly charged ${\Sigma }_c$ decays.

We consider time-dependent Lifshitz-type solutions in type IIB supergravity. The solutions describe a time evolution from Lifshitz spacetimes to AdS spaces. We argue the holographic relation of them to aging phenomena in condensed matter physics. The solutions have no time-translation invariance and possess the dynamical scaling symmetry with $z_c=2$. In addition, the time evolution corresponds to slow (nonexponential) dynamics from nonequilibrium states to the equilibrium. We also discuss a mechanism of quantum quench to generate nonequilibrium states.