We explore the ability of three-particle templates to distinguish color neutral objects from QCD background. This method is particularly useful to identify the standard model Higgs, as well as other massive neutral particles. Simple cut-based analysis in the overlap distributions of the signal and background is shown to provide a significant rejection power. By combining with other discriminating variables, such as planar flow, and several variables that depend on the partonic template, three-particle templates are used to characterize the influence of gluon emission and color flow in collider events. The performance of the method is discussed for the case of a highly boosted Higgs in association with a leptonically decaying $W$ boson.

The relatively small binding energy in nuclei suggests that they may be well represented by near-BPS Skyrmions since their mass is roughly proportional to the baryon number $A$. For that purpose, we propose a generalization of the Skyrme model with terms up to order six in derivatives of the pion fields and treat the nonlinear $\sigma$ and Skyrme terms as small perturbations. For our special choice of mass term (or potential) $V$, we obtain well-behaved analytical BPS-type solutions with nonshell configurations for the baryon density, as opposed to the more complex shell-like configurations found in most extensions of the Skyrme model. Along with static and (iso)rotational energies, we add to the mass of the nuclei the often neglected Coulomb energy and isospin breaking term. Fitting the four model parameters, we find a remarkable agreement for the binding energy per nucleon $B/A$ with respect to experimental data. These results support the idea that nuclei could be near-BPS Skyrmions.

We study the neutron electric dipole moment in the presence of the $CP$-violating operators up to dimension five in terms of the QCD sum rules. It is found that the operator product expansion calculation is robust when exploiting a particular interpolating field for a neutron, while there exist some uncertainties on the phenomenological side. By using input parameters obtained from the lattice calculation, we derive a conservative limit for the contributions of the $CP$-violating operators. We also show the detail of the derivation of the sum rules.

In contrast to perturbative QCD, the analytic QCD models have running coupling whose analytic properties correctly mirror those of spacelike observables. The discontinuity (spectral) function of such running coupling is expected to agree with the perturbative case at large timelike momenta; however, at low timelike momenta, it is not known. In the latter regime, we parametrize the unknown behavior of the spectral function as a sum of (two) delta functions; while the onset of the perturbative behavior of the spectral function is set to be $1.0–1.5\mathrm{GeV}$. This is in close analogy with the “minimal hadronic ansatz” used in the literature for modeling spectral functions of correlators. For the running coupling itself, we impose the condition that it basically merges with the perturbative coupling at high spacelike momenta. In addition, we require that the well-measured nonstrange semihadronic ($V+A$) tau decay ratio value be reproduced by the model. We thus obtain a QCD framework which is basically indistinguishable from perturbative QCD at high momenta ($Q>1\mathrm{GeV}$), and at low momenta, it respects the basic analyticity properties of spacelike observables as dictated by the general principles of the local quantum field theories.

By solving the Faddeev equations we calculate the mass of the strange baryons in the framework of a relativistic constituent quark model. The Goldstone-boson-exchange quark-quark interaction is derived from $SU(3{)}_F$ symmetry, which is explicitly broken as the strange quark is much heavier. This broken symmetry can nicely be accounted for in the Faddeev framework.

We consider the phenomenology of the gauged Abelian symmetry $B+3(L_e-L_{\mu }-L_{\tau })$. Right-handed neutrinos necessary to cancel triangle anomalies are used in a type-I seesaw scheme to create active neutrino masses. Breaking the $B+3(L_e-L_{\mu }-L_{\tau })$ symmetry spontaneously below the seesaw scale generates low-energy neutrino mass matrices with the approximate symmetries $L_e$ (leading to normal hierarchy) or $L_e-L_{\mu }-L_{\tau }$ (inverted hierarchy). For the latter we need to introduce a ${\mathbb{Z}}_2$ symmetry which decouples one of the right-handed neutrinos. If exact, this ${\mathbb{Z}}_2$ leads to a Majorana dark matter candidate that interacts with the standard model via the $Z^{\prime }$ and a scalar $s$ originating from spontaneous breaking of the new symmetry. The measured relic abundance of the dark matter particle can be obtained around the scalar and $Z^{\prime }$ resonances, while direct detection experiments are mainly sensitive to scalar exchange, which is induced by mass mixing of $s$ with the standard Higgs.

The coupling of the baryonic current to new neutrino states ${\nu }_b$ with strength in excess of the weak interactions is a viable extension of the standard model. We analyze the signature of ${\nu }_b$ appearance in the solar neutrino flux that gives rise to an elastic scattering signal in dark matter direct detection and in solar neutrino experiments. This paper lays out an in-depth study of ${\nu }_b$ detection prospects for current and future underground rare event searches. We scrutinize the model as a possible explanation for the reported anomalies from DAMA, CoGeNT, and CRESST-II and confront it with constraints from other null experiments.

We extend a covariant model, tested before in the spacelike region for the physical and lattice QCD regimes, to a calculation of the ${\gamma }^{*}N\to \Delta$ reaction in the timelike region, where the square of the transfered momentum, $q^2$, is positive ($q^2>0$). We estimate the Dalitz decay $\Delta \to N{e}^{+}{e}^{-}$ and the $\Delta$ distribution mass distribution function. The results presented here can be used to simulate the $NN\to NN{e}^{+}{e}^{-}$ reactions at moderate beam kinetic energies.

Lepton flavor violation has been observed in neutrino oscillations. For charged lepton flavor violation decays only upper limits are known, but sizable branching ratios are expected in many neutrino mass models. High-scale models, such as the classical supersymmetric seesaw, usually predict that decays $l_i\to 3l_j$ are roughly a factor $\alpha$ smaller than the corresponding decays $l_i\to l_j\gamma$. Here we demonstrate that the $Z^0$-penguin diagram can give an enhancement for decays $l_i\to 3l_j$ in many extensions of the minimal supersymmetric standard model (MSSM). We first discuss why the $Z^0$-penguin is not dominant in the MSSM with seesaw and show that much larger contributions from the $Z^0$-penguin are expected in general. We then demonstrate the effect numerically in two example models, namely, the supersymmetric inverse seesaw and $R$-parity violating supersymmetry.

We investigate the prospects for distinguishing dark matter annihilation channels using the neutrino flux from gravitationally captured dark matter particles annihilating inside the sun. We show that, even with experimental error in energy reconstruction taken into account, the spectrum of contained muon tracks may be used to discriminate neutrino final states from the gauge boson/charged lepton final states and to determine their corresponding branching ratios. We also discuss the effect of ${\nu }_{\tau }$ regeneration inside the sun as a novel method to distinguish the flavor of final state neutrinos. This effect as evidenced in the muon spectrum becomes important for dark matter masses above 300 GeV. Distinguishing primary neutrinos and their flavor may be achieved using multiyear data from a detector with the same capability and effective volume as the IceCube/DeepCore array.

We present the first measurement of the angle ${\varphi }_3$ of the unitarity triangle using a model-independent Dalitz plot analysis of $B^{\pm }\to D{K}^{\pm }$, $D\to K_S^0{\pi }^{+}{\pi }^{-}$ decays. The method uses, as input, measurements of the strong phase of the $D\to K_S^0{\pi }^{+}{\pi }^{-}$ amplitude from the CLEO Collaboration. The result is based on the full data set of $772\times {10}^6$ $B\overline{B}$ pairs collected by the Belle experiment at the ${\rm Y}(4S)$ resonance. We obtain ${\varphi }_3=({77.3}_{-14.9}^{+15.1}\pm 4.1\pm 4.3)°$ and the suppressed amplitude ratio $r_B=0.145\pm 0.030\pm 0.010\pm 0.011$. Here the first error is statistical, the second is the experimental systematic uncertainty, and the third is the error due to the precision of the strong-phase parameters obtained by CLEO.

We consider the critical gravity theory with a scalar field in four dimensions. We find that this theory has the solution corresponding to the Minkowski background, in addition to the de Sitter (dS) and the anti-de Sitter (AdS) backgrounds, depending on whether the action includes the cosmological term or not. We should note that the Minkowski background is the solution which cannot be obtained in the model without a scalar field. Furthermore, when we choose the parameters to eliminate the scalar graviton, the additional scalar field is also simultaneously eliminated. At the critical point, we show that the Abbott-Deser (AD) mass of the Schwarzschild-de Sitter (SdS) black hole and the energy for the massless graviton vanish, whose situation is not changed from the model without a scalar field.

We discuss the supersymmetry and fermionic sector of the recently obtained consistent truncations of IIB supergravity containing massive modes. In particular, we present the general form of the five-dimensional $\mathcal{N}=4$ supersymmetry transformations and equations of motion for the fermions arising in the reduction of IIB theory on $T^{1,1}$ which contains all modes invariant under the $\mathrm{SU}(2)\times \mathrm{SU}(2)$ isometry group. The $\mathcal{N}=4$ reduction can be further truncated to two different $\mathcal{N}=2$ subsectors. For each of these, we present the $\mathcal{N}=2$ fermionic supersymmetry transformations and corresponding superpotentials. As an application, we obtain the explicit Killing spinors of the Klebanov-Strassler solution and comment on the relation to the ansatz of Papadopoulos and Tseytlin. We also demonstrate the applicability of consistent truncations on squashed Sasaki-Einstein manifolds to a class of flux compactifications, focusing on a recent solution describing the geometry of gaugino condensation on wrapped D7 branes and which possesses dynamic SU(2) structure.

We estimate the transition rates of a uniformly accelerated Unruh-DeWitt detector coupled to a quantum field with reflecting conditions on a boundary plane (a “mirror”). We find that these are essentially indistinguishable from the usual Unruh rates, viz. that the Unruh effect persists in the presence of the mirror. This shows that the Unruh effect (thermality of detector rates) is not merely a consequence of the entanglement between left and right Rindler quanta in the Minkowski vacuum. Since in this setup the state of the field in the Rindler wedge is pure, we argue furthermore that the relevant entropy in the Unruh effect cannot be the von Neumann entanglement entropy. We suggest, an alternative, that it is the Shannon entropy associated with Heisenberg uncertainty.

Current constraints on $f(R)$ gravity from the large-scale structure are at the verge of penetrating into a region where the modified forces become nonlinearly suppressed. For a consistent treatment of observables at these scales, we study cluster quantities produced in chameleon and linearized Hu-Sawicki $f(R)$ gravity dark matter $N$-body simulations. We find that the standard Navarro-Frenk-White halo density profile and the radial power law for the pseudo-phase-space density provide equally good fits for $f(R)$ clusters as they do in the Newtonian scenario. We give qualitative arguments for why this should be the case. For practical applications, we derive analytic relations, e.g., for the $f(R)$ scalar field, the gravitational potential, and the velocity dispersion as seen within the virialized clusters. These functions are based on three degrees of freedom fitted to simulations, i.e., the characteristic density, scale, and velocity dispersion. We further analyze predictions for these fitting parameters from the gravitational collapse and the Jeans equation, which are found to agree well with the simulations. Our analytic results can be used to consistently constrain chameleon $f(R)$ gravity with future observations on virialized cluster scales without the necessity of running a large number of simulations.

Excesses on positron and electron fluxes—measured by ATIC and the PAMELA and Fermi-LAT telescopes—can be explained by dark matter annihilation in the Galaxy, however, it requires large boosts on the dark matter annihilation rate. There are many possible enhancement mechanisms such as the Sommerfeld effect or the existence of dark matter clumps in our halo. If enhancements on the dark matter annihilation cross section are taking place, the dark matter annihilation in the core of the Earth will be enhanced. Here we use recent results from the IceCube 40-string configuration to probe generic enhancement scenarios. We present results as a function of the dark matter-proton interaction cross section, ${\sigma }_{\chi p}$ weighted by the branching fraction into neutrinos $f_{\nu \overline{\nu }}$ as a function of a generic boost factor $B_F$, which parametrizes the expected enhancement of the annihilation rate. We find that dark matter models that require annihilation enhancements of $\mathcal{O}(100)$ or more and that annihilate significantly into neutrinos are excluded as an explanation for these excesses. We also determine the boost range that can be probed by the full IceCube telescope.

Recently a new particle physics model called bound dark matter (BDM) has been proposed [A. de la Macorra, Astropart. Phys. 33, 195 (2010).] in which dark matter (DM) particles are massless above a threshold energy ($E_c$) and acquire mass below it due to nonperturbative methods. Therefore, the BDM model describes DM particles which are relativistic, hot dark matter (HDM) in the inner regions of galaxies and describes nonrelativistic, cold dark matter (CDM) where halo density is below ${\rho }_c\equiv E_c^4$. To realize this idea in galaxies, we use a particular DM cored profile that contains three parameters: a typical scale length ($r_s$) and density (${\rho }_0$) of the halo, and a core radius ($r_c$) stemming from the relativistic nature of the BDM model. We test this model by fitting rotation curves of 17 low surface brightness (LSB) galaxies from The HI Nearby Galaxy Survey (THINGS). Since the energy $E_c$ parametrizes the phase transition due to the underlying particle physics model, it is not dependent on the details of galaxy and/or structure formation and therefore the DM profile parameters $r_s$, $r_c$, $E_c$ are constrained, leaving only two free parameters. The high spatial and velocity resolution of this sample allows one to derive the model parameters through the numerical implementation of the ${\chi }^2$-goodness-of-fit test to the mass models. We compare the fittings with those of Navarro-Frenk-White (NFW), Burkert, and pseudoisothermal (ISO) profiles. Through the results, we conclude that the BDM profile fits better, or equally well, than NFW, Burkert, and ISO profiles and agree with previous results implying that cored profiles are preferred over the $N$-body motivated cuspy profiles. We also compute two-dimensional likelihoods of the BDM parameters $r_c$ and $E_c$ for the different galaxies and matter contents, and find an average galaxy core radius $r_c=300\mathrm{pc}$ and a transition energy between hot and cold dark matter at $E_c={0.11}_{-0.07}^{+0.21}\mathrm{eV}$ when the DM halo is the only component and therefore the maximum dark matter contribution in galaxies. In a more realistic analysis, as in the Kroupa mass model, we obtain a core $r_c=1.48\mathrm{kpc}$, and energy $E_c={0.06}_{-0.03}^{+0.07}\mathrm{eV}$.

There is a broad class of astrophysical sources that produce detectable, transient, gravitational waves. Some searches for transient gravitational waves are tailored to known features of these sources. Other searches make few assumptions about the sources. Typically events are observable with multiple search techniques. This work describes how to combine the results of searches that are not independent, treating each search as a classifier for a given event. This will be shown to improve the overall sensitivity to gravitational-wave events while directly addressing the problem of consistent interpretation of multiple trials.

We describe a general approach to detection of transient gravitational-wave signals in the presence of non-Gaussian background noise. We prove that under quite general conditions, the ratio of the likelihood of observed data to contain a signal to the likelihood of it being a noise fluctuation provides optimal ranking for the candidate events found in an experiment. The likelihood-ratio ranking allows us to combine different kinds of data into a single analysis. We apply the general framework to the problem of unifying the results of independent experiments and the problem of accounting for non-Gaussian artifacts in the searches for gravitational waves from compact binary coalescence in LIGO data. We show analytically and confirm through simulations that in both cases applying the likelihood-ratio ranking results in an improved analysis.