The semi-inclusive $B$-meson decay into spin-singlet $D$-wave $2^{-+}$ charmonium, $B\to {\eta }_{c2}+X$, is studied in nonrelativistic QCD. Both color-singlet and color-octet contributions are calculated at next-to-leading order in the strong coupling constant ${\alpha }_s$. The nonperturbative long-distance matrix elements are evaluated using operator evolution equations. It is found that the color-singlet ${}^{1}D_2$ contribution is tiny, while the color-octet channels make dominant contributions. The estimated branching ratio $B(B\to {\eta }_{c2}+X)$ is about $0.41\times {10}^{-4}$ in the naïve dimensional regularization scheme and $1.24\times {10}^{-4}$ in the ’t Hooft–Veltman scheme, with renormalization scale $\mu =m_b=4.8\mathrm{GeV}$. The scheme sensitivity of these numerical results is due to cancellation between ${}^{1}S_0^{[8]}$ and ${}^{1}P_1^{[8]}$ contributions. The $\mu$-dependence curves of next-to-leading order branching ratios in both schemes are also shown, with $\mu$ varying from $\frac{m_b}{2}$ to $2m_b$ and the nonrelativistic QCD factorization or renormalization scale ${\mu }_{\Lambda }$ taken to be $2m_c$. Comparison of the estimated branching ratio of $B\to {\eta }_{c2}+X$ with the observed branching ratio of $B\to X(3872)+K$ may lead to the conclusion that $X(3872)$ is unlikely to be the $2^{-+}$ charmonium state ${\eta }_{c2}$.

We consider the 2-loop finite temperature effective potential for a standard-model-like Higgs boson, allowing Higgs boson couplings to additional scalars. If the scalars transform under color, they contribute 2-loop diagrams to the effective potential that include gluons. These 2-loop effects are perhaps stronger than previously appreciated. For a Higgs boson mass of 115 GeV, they can increase the strength of the phase transition by as much as a factor of 3.5. It is the analogue of this effect that is responsible for the survival of the tenuous electroweak baryogenesis window of the minimal supersymmetric standard model. We further illuminate the importance of these 2-loop diagrams by contrasting models with colored scalars to models with singlet scalars. We conclude that baryogenesis favors models with light colored scalars. This motivates searches for pair-produced dijet resonances or $\mathrm{\text{jet}}(\mathrm{s})+{\mathrm{E̸}}_T$.

We discuss consequences of combining the effective $Z_2\times Z_2$ symmetry of the tribimaximal neutrino mass matrix with the $CP$ symmetry. Imposition of such generalized $Z_2\times Z_2$ symmetries leads to predictive neutrino mass matrices determined in terms of only four parameters and leads to a nonzero ${\theta }_{13}$ and maximal atmospheric mixing angle and $CP$ violating phase. It is shown that an effective generalized $Z_2\times Z_2$ symmetry of the mass matrix can arise from the $A_4$ symmetry with specific vacuum alignment. The neutrino mass matrix in the considered model has only three real parameters and leads to determination of the absolute neutrino mass scale as a function of the reactor angle ${\theta }_{13}$.

In the chiral magnetic effect, there is a competition between a strong magnetic field, which tends to project positively charged particles to have spin aligned along the magnetic field, and a chirality imbalance which may be produced locally by a topologically nontrivial gauge field such as an instanton. We study the properties of the Euclidean Dirac equation for a light fermion in the presence of both a constant Abelian magnetic field and an SU(2) instanton. In particular, we analyze the zero modes analytically in various limits, both on ${\mathbf{R}}^4$ and on the four-torus, in order to compare with recent lattice QCD results, and study the implications for the electric dipole moment.

The $d=5$ Reissner-Nordström black hole becomes unstable when considered as a solution of Einstein–Yang-Mills–Chern-Simons theory. The existence of a marginally stable mode gives rise to a new branch of black holes with non-Abelian magnetic fields outside the horizon. These solutions carry a nonzero electric charge and have finite mass. We argue that these features manifest themselves both for Minkowski and (anti-)de Sitter asymptotics. The properties of solutions in a de Sitter background are new to the present work and are emphasized. All solutions constructed have finite mass by virtue of the presence of the Chern-Simons term, which in $d=5$ plays the role of a higher order term scaling appropriately for this purpose.

We investigate the thermodynamics of critical phenomena in Born-Infeld AdS black holes using a canonical ensemble. The critical behavior has been studied near the critical point which is characterized by a discontinuity in the heat capacity at constant charge. We explicitly calculate the critical exponents of the relevant thermodynamic quantities. These exponents satisfy all the thermodynamic scaling laws. We also check the generalized homogeneous function hypothesis (or the scaling hypothesis) which is shown to be compatible with the thermodynamic scaling laws. Finally we check the validity of the scaling laws of second kind which include the critical exponents associated with the spatial correlation. In the appropriate limit our results also provide the corresponding expressions for the Reissner-Nordstrom AdS case.

We study a number of different ingredients related to $\theta$ dependence, the nondispersive contribution in topological susceptibility with the wrong sign, topological sectors in gauge theories, and related subjects using a simple “deformed QCD.” This model is a weakly coupled gauge theory, which however has all the relevant essential elements allowing us to study difficult and nontrivial questions which are known to be present in real strongly coupled QCD. Essentially, we want to test the ideas related to the $U(1{)}_A$ problem in a theoretically controllable manner using the “deformed QCD” as a toy model. One can explicitly see microscopically how the crucial elements work.

Simple models for unitary black hole evolution are given in an effective Hilbert-space description, parameterizing a possible minimal relaxation of locality, with respect to semiclassical black hole geometry.

A method is given to compute an approximation to the noise kernel, defined as the symmetrized connected two-point function of the stress tensor, for the conformally invariant scalar field in any spacetime conformal to an ultrastatic spacetime for the case in which the field is in a thermal state at an arbitrary temperature. The most useful applications of the method are flat space where the approximation is exact and Schwarzschild spacetime where the approximation is better than it is in most other spacetimes. The two points are assumed to be separated in a timelike or spacelike direction. The method involves the use of a Gaussian approximation which is of the same type as that used by Page [D. N. Page, Phys. Rev. D 25, 1499 (1982).] to compute an approximate form of the stress tensor for this field in Schwarzschild spacetime. All components of the noise kernel have been computed exactly for hot flat space and one component is explicitly displayed. Several components have also been computed for Schwarzschild spacetime and again one component is explicitly displayed.

We provide an explicit structure of the charged-lepton mass matrix which is 2-3 symmetric except for a single breaking of this symmetry by the muon mass. We identify a flavor symmetric limit for the mass matrices where the first generation is decoupled from the other two in the charged-lepton sector while in the neutrino sector the third generation is decoupled from the first two generations. The leptonic mixing in the symmetric limit can be, among other structures, the bimaximal or the tri-bimaximal mixing. Symmetry breaking effects are included both in the charged-lepton and the neutrino sector to produce corrections to the leptonic mixing and explain the recent ${\theta }_{13}$ measurements. A model that extends the standard model by three right-handed neutrinos, an extra Higgs doublet, and two singlet scalars is introduced to generate the leptonic mixing.

In this work, we consider searches for dark matter made of axions or axionlike particles using resonant radio frequency cavities inserted into dipole magnets from particle accelerators, wiggler magnets developed for accelerator based advanced light sources, and toroidal magnets similar to those used in particle-physics detectors. We investigate the expected sensitivity of such axionlike-particle dark-matter detectors and discuss the engineering aspects of building and tuning them. Brief mention is also made of even stronger field magnets which are becoming available due to improvements in magnetic technology. It is concluded that new experiments utilizing already-existing magnets could greatly enlarge the mass region in searches for axionlike dark matter particles.

According to the generally accepted phase diagram of QCD, at low temperature and high baryon number density the chiral phase transition of QCD is of first order and the coexistence of the Nambu-Goldstone phase and the Wigner phase should appear. This is in conflict with the usual claim that the quark gap equation has no Wigner solution in the case of nonzero current quark mass. In this paper we analyze the reason why the Wigner solution does not exist in the usual treatment and try to propose a new approach to discuss this question. As a first step, we adopt a modified Nambu-Jona-Lasinio (NJL) model to study the Wigner solution at finite current quark mass. We then generalize this approach to the case of finite chemical potential and discuss partial restoration of chiral symmetry at finite chemical potential and compare our results with those in the normal NJL model.

We derive the single-spin-dependent cross section for the Drell-Yan lepton-pair production and the direct-photon production in the $pp$ collision induced by the twist-3 three-gluon correlation functions in the transversely polarized nucleon in the leading order with respect to the QCD coupling constant. Combined with the contribution from the twist-3 quark-gluon correlation functions in the literature, this completes the twist-3 cross section for these processes. We also present a model calculation of the asymmetry for the direct-photon production at the relativistic heavy ion collider (RHIC) energy, demonstrating the sensitivity of the asymmetry to the form of the three-gluon correlation functions. In particular, we show that the asymmetry in the backward direction of the polarized nucleon is determined by the small-$x$ behavior of the correlation functions.

An inclusive search for anomalous production of two prompt, isolated muons with the same electric charge is presented. The search is performed in a data sample corresponding to $1.6{\mathrm{fb}}^{-1}$ of integrated luminosity collected in 2011 at $\sqrt{s}=7\mathrm{TeV}$ with the ATLAS detector at the LHC. Muon pairs are selected by requiring two isolated muons of the same electric charge with $p_{\mathrm{T}}>20\mathrm{GeV}$ and $|\eta |<2.5$. Minimal requirements are placed on the rest of the event activity. The distribution of the invariant mass of the muon pair $m(\mu \mu )$ is found to agree well with the background expectation. Upper limits on the cross section for anomalous production of two muons with the same electric charge are placed as a function of $m(\mu \mu )$ within a fiducial region defined by the event selection. The fiducial cross-section limit constrains the like-sign top-quark pair-production cross section to be below 3.7 pb at 95% confidence level. The data are also analyzed to search for a narrow like-sign dimuon resonance as predicted for e.g. doubly charged Higgs bosons ($H^{\pm \pm }$). Assuming pair production of $H^{\pm \pm }$ bosons and a branching ratio to muons of 100% (33%), this analysis excludes masses below 355 (244) GeV and 251 (209) GeV for $H^{\pm \pm }$ bosons coupling to left-handed and right-handed fermions, respectively.

In this paper we perform a nonperturbative analysis of a thermal quasifermion in thermal QCD/QED by studying its self-energy function through the Dyson-Schwinger equation with the hard-thermal-loop resummed improved ladder kernel. Our analysis reveals several interesting results, some of which may force us to change the image of the thermal quasifermion: (1) The thermal mass of a quasifermion begins to decrease as the coupling gets stronger and finally disappears in the strong coupling region, (2) the imaginary part of the chiral invariant mass function (i.e., the decay width of the quasifermion) persists to have $O(g^{2}T\log (1/g))$ behavior. Present results suggest that in the recently produced strongly coupled quark-gluon plasma, the thermal mass of a quasifermion should vanish. We also briefly comment on evidence of the existence of a massless, or an ultrasoft, mode.

We discuss gauge mediation in the case where the hidden sector is strongly coupled but, via the gauge-gravity correspondence, admits a weakly-coupled description in terms of a warped higher-dimensional spacetime. In this framework, known as holographic gauge mediation, the visible-sector gauge group is realized in the gravitational description by probe D-branes and the nonsupersymmetric state by normalizable perturbations to the geometry. Using the formalism of general gauge mediation, supersymmetry-breaking soft terms in the visible sector can be related to the two-point functions of the hidden-sector current superfield that couples to the visible-sector gauge group. Such correlation functions cannot be directly calculated in the strongly coupled field theory but can be determined using the gauge-gravity correspondence and holographic renormalization. We explore this procedure by considering a toy geometry where such two-point functions can be explicitly calculated. Unlike previous implementations of holographic gauge mediation where sfermion masses were not calculable directly in a purely holographic framework, such terms are readily obtained via these correlators, while (due to the simplicity of the geometry considered) the visible-sector gauginos remain massless to leading order in the visible-sector coupling.

The primordial non-Gaussianity of local type affects the clustering of dark matter halos, and the planned deep and wide photometric surveys are suitable for examining this class of non-Gaussianity. In our previous paper, we investigated the constraint from the cross correlation between CMB-lensing potential and galaxy angular distribution on the primordial non-Gaussianity, without taking into account redshift slicing. To improve our previous analysis, in this paper, we add the galaxy-lensing shear into our analysis and take into account redshift slicing to follow the redshift evolution of the clustering. By calculating 81 power spectra and using the Fisher matrix method, we find that the constraint on the primordial non-Gaussianity can be improved from $\Delta f_{\mathrm{NL}}\sim 5.4$ to 5.1 by including the galaxy-galaxy-lensing shear cross correlations expected from the Hyper Suprime-Cam survey, in comparison with the constraint without any cross correlations. Moreover, the constraint can go down to $\Delta f_{\mathrm{NL}}\sim 4.8$ by including the galaxy-CMB lensing cross correlations from the ACTPol and Planck experiments.

We solve the cosmological evolution of warm dark matter density fluctuations within the analytic framework of the Volterra integral equations presented in the accompanying paper [H. J. de Vega and N. G. Sanchez, preceding Article, Phys. Rev. D 85, 043516 (2012).]. In the absence of neutrinos, the anisotropic stress vanishes and the Volterra-type equations reduce to a single integral equation. We solve numerically this single Volterra-type equation both for dark matter (DM) fermions decoupling at thermal equilibrium and DM sterile neutrinos decoupling out of thermal equilibrium. We give the exact analytic solution for the density fluctuations and gravitational potential at zero wave number. We compute the density contrast as a function of the scale factor $a$ for a relevant range of wave numbers $k$. At fixed $a$, the density contrast turns to grow with $k$ for $k<k_c$ while it decreases for $k>k_c$, where $k_c\simeq 1.6/\mathrm{Mpc}$. The density contrast depends on $k$ and $a$ mainly through the product $ka$ exhibiting a self-similar behavior. Our numerical density contrast for small $k$ gently approaches our analytic solution for $k=0$. For fixed $k<1/(60\mathrm{kpc})$, the density contrast generically grows with $a$ while for $k>1/(60\mathrm{kpc})$ it exhibits oscillations starting in the radiation dominated era which become stronger as $k$ grows. We compute the transfer function of the density contrast for thermal fermions and for sterile neutrinos decoupling out of equilibrium in two cases: the Dodelson-Widrow model and a model with sterile neutrinos produced by a scalar particle decay. The transfer function grows with $k$ for small $k$ and then decreases after reaching a maximum at $k=k_c$ reflecting the time evolution of the density contrast. The integral kernels in the Volterra equations are nonlocal in time and their falloff determine the memory of the past evolution since decoupling. We find that this falloff is faster when DM decouples at thermal equilibrium than when it decouples out of thermal equilibrium. Although neutrinos and photons can be neglected in the matter dominated matter dominated era, they contribute to the Volterra integral equation in the MD era through their memory from the radiation dominated era.