Thu·Nov 5, 2015Thursday·November 5, 2015

1. 01*

   Non-linear Higgs portal to Dark Matter

   I. Brivio🇪🇸 · M.B. Gavela🇪🇸 · L. Merlo🇪🇸 · K. Mimasu🇬🇧 · J.M. No🇬🇧 · R. del Rey🇪🇸 · V. Sanz🇬🇧

   The Higgs portal to scalar Dark Matter is considered in the context of non-linearly realised electroweak symmetry breaking. We determine the dominant interactions of gauge bosons and the physical Higgs particle $h$ to a scalar singlet dark matter candidate. Phenomenological consequences are also studied in detail, including the possibility of distinguishing this scenario from the standard Higgs portal in which the electroweak symmetry breaking is linearly realised. Two features of significant impact are: i) the connection between the electroweak scale $v$ and the Higgs particle departs from the $(v+h)$ functional dependence, as the Higgs field is not necessarily an exact electroweak doublet; ii) the presence of specific couplings that arise at different order in the non-linear and in the linear expansions. These facts deeply affect the dark matter relic abundance, as well as the expected signals in direct and indirect searches and collider phenomenology, where Dark Matter production rates are enhanced with respect to the standard portal.

   hep-phJHEP(2016)·45 citations
2. 02*

   Bounding wide composite vector resonances at the LHC

   Daniele Barducci🇫🇷 · Cédric Delaunay🇫🇷

   In composite Higgs models (CHMs), electroweak precision data generically push colourless composite vector resonances to a regime where they dominantly decay into pairs of light top partners. This greatly attenuates their traces in canonical collider searches, tailored for narrow resonances promptly decaying into Standard Model final states. By reinterpreting the CMS same-sign dilepton (SS2$\ell$) analysis at the Large Hadron Collider (LHC), originally designed to search for top partners with electric charge $5/3$, we demonstrate its significant coverage over this kinematical regime. We also show the reach of the 13 TeV run of the LHC, with various integrated luminosity options, for a possible upgrade of the SS2$\ell$ search. The top sector of CHMs is found to be more fine-tuned in the presence of colourless composite resonances in the few TeV range.

   hep-phJHEP(2016)·25 citations
3. 03*

   Minicharged Particles from the Sun: A Cutting-Edge Bound

   Núria Vinyoles🇪🇸 · Hendrik Vogel🇩🇪

   We study the impact on the Sun of an exotic energy-loss channel caused by plasmon decay into fermionic minicharged particles with charge $ϵe$ and mass $m_f$. We compare solar models with this extra emission to helioseismological and neutrino data, obtaining a bound $ϵ<2.2\times 10^{-14}(95\%\mathrm{CL})$ for $m_f\lesssim 25\text{eV}$. Our result is comparable to previous limits from the cooling of globular cluster stars, while at the same time it is better understood and takes theoretical and observational errors into account.

   hep-phastro-ph.SRJCAP(2016)·57 citations
4. 04*

   Constraints on mass dimension one fermionic dark matter from the Yukawa interaction

   Marco Dias🇧🇷 · Cheng-Yang Lee🇧🇷

   We study the loop corrections to the scalar propagator and the fermionic self-energy for the mass dimension one fermionic dark matter with the Yukawa interaction. We find, in the former case, there is a non-vanishing Lorentz-violating term while the later is Lorentz-invariant. Our study of the fermionic loop correction shows that unitarity demands the fermionic mass must be at least half of the bosonic mass and that the Lorentz-violating term makes a non-trivial correction to the bosonic propagator. We discuss what these results mean in the context of the Standard Model and the possibility of bypassing the unitarity constraint. In the simplest scenario, within the framework of standard quantum field theory, by identifying the scalar boson to be the Higgs boson with a mass of 125 GeV, the mass of the fermion must be at least 62.5 GeV.

   hep-phhep-thPRD(2016)·31 citations
5. 05*

   The QCD evolution of TMD in the covariant approach

   A.V. Efremov🇷🇺 · O.V. Teryaev🇷🇺 · P. Zavada🇨🇿

   The procedure for calculation of the QCD evolution of transverse momentum dependent distributions within the covariant approach is suggested. The standard collinear QCD evolution together with the requirements of relativistic invariance and rotational symmetry of the nucleon in its rest frame represent the basic ingredients of our approach. The obtained results are compared with the predictions of some other approaches.

   hep-phJ.Phys.Conf.Ser.(2016)·2 citations
6. 06*

   Neutrino-induced meson productions

   Satoshi X. Nakamura (Osaka University)🇯🇵

   We develop a dynamical coupled-channels (DCC) model for neutrino-nucleon reactions in the resonance region, by extending the DCC model that we have previously developed through an analysis of $\pi N,\gamma N\to \pi N,\eta N,K\Lambda ,K\Sigma$ reaction data for $W\le 2.1$ GeV. We analyze electron-induced reaction data for both proton and neutron targets to determine the vector current form factors up to $Q^2\le$ 3.0 (GeV/$c$)${}^2$. Axial-current matrix elements are derived in accordance with the Partially Conserved Axial Current (PCAC) relation to the $\pi N$ interactions of the DCC model. As a result, we can uniquely determine the interference pattern between resonant and non-resonant amplitudes. Our calculated cross sections for neutrino-induced single-pion productions are compared with available data, and are found to be in reasonable agreement with the data. We also calculate the double-pion production cross sections in the resonance region, for the first time, with relevant resonance contributions and channel couplings. The result is compared with the double-pion production data. For a future development of a neutrino-nucleus reaction model and/or a neutrino event generator for analyses of neutrino experiments, the DCC model presented here can give a useful input.

   hep-phhep-exnucl-thJPS Conf.Proc.(2016)·1 citation
7. 07*

   Compositeness of baryonic resonances: Applications to the Delta(1232), N(1535), and N(1650) resonances

   Takayasu Sekihara (Osaka U., Res. Ctr. Nucl. Phys.)🇯🇵 · Takashi Arai (KEK, Tsukuba)🇯🇵 · Junko Yamagata-Sekihara (Nat. Inst. Tech., Oshima Coll.)🇯🇵 · Shigehiro Yasui (Tokyo Inst. Tech.)🇯🇵

   We present a formulation of the compositeness for baryonic resonances in order to discuss the meson-baryon molecular structure inside the resonances. For this purpose, we derive a relation between the residue of the scattering amplitude at the resonance pole position and the two-body wave function of the resonance in a sophisticated way, and we define the compositeness as the norm of the two-body wave functions. As applications, we investigate the compositeness of the $\Delta (1232)$, $N(1535)$, and $N(1650)$ resonances from precise $\pi N$ scattering amplitudes in a unitarized chiral framework with the interaction up to the next-to-leading order in chiral perturbation theory. The $\pi N$ compositeness for the $\Delta (1232)$ resonance is evaluated in the $\pi N$ single-channel scattering, and we find that the $\pi N$ component inside $\Delta (1232)$ in the present framework is nonnegligible, which supports the previous work. On the other hand, the compositeness for the $N(1535)$ and $N(1650)$ resonances is evaluated in a coupled-channels approach, resulting that the $\pi N$, $\eta N$, $K\Lambda$ and $K\Sigma$ components are negligible for these resonances.

   hep-phhep-exnucl-exnucl-thPRC(2016)·46 citations
8. 08*

   Symmetry breaking effect on the inhomogeneous chiral transition in the magnetic field

   Ryo Yoshiike🇯🇵 · Toshitaka Tatsumi🇯🇵

   We study the change of the effect of the current quark mass on the inhomogeneous chiral phase in the QCD phase diagram, and discuss the property of the phase transition by the generalized Ginzburg-Landau expansion. The strong external magnetic field spreads this phase over the low chemical potential region even if the current quark mass is finite. This implies that the existence of this phase can be explored by the lattice QCD simulation.

   hep-phPRD(2015)·13 citations
9. 09*

   Heavy ion theory: Review of recent developments with a first principles bias

   Aleksi Vuorinen🇫🇮

   We discuss a number of prominent theoretical challenges in the physics of ultrarelativistic heavy ion collisions, and review some recent attempts to tackle them. These examples cover most stages of the collision process, but emphasis is given to approaches that rely on first principles methods or well-established Effective Field Theory frameworks. The topics discussed in most detail include the early dynamics of a collision as well as the properties of quark gluon plasma in thermal equilibrium.

   hep-phPoS(2015)·3 citations
10. 10*

    MBsums - a Mathematica package for the representation of Mellin-Barnes integrals by multiple sums

    Michal Ochman🇩🇪 · Tord Riemann🇩🇪

    Feynman integrals may be represented by the Mathematica packages AMBRE and MB as multiple Mellin-Barnes integrals. With the Mathematica package MBsums these Mellin-Barnes integrals are transformed into multiple sums.

    hep-phActa Phys.Polon.B(2015)·40 citations
11. 11*

    The HLS approach to $(g-2{)}_{\mu }$~: A Solution to the "$\tau$ versus $e^{+}{e}^{-}$" Puzzle

    Maurice Benayoun🇫🇷

    The Hidden Local Symmetry (HLS) Model provides a framework able to encompass several physical processes and gives a unfied description of these in an energy range extending up to the $\varphi$ mass. Supplied with appropriate symmetry breaking schemes, the HLS Model gives a broken Effective Lagrangian (BHLS). The BHLS Lagrangian gives rise to a fit procedure in which a simultaneous description of the $e^{+}{e}^{-}$ annihilations to ${\pi }^{+}{\pi }^{-}$, ${\pi }^0\gamma$, $\eta \gamma$, ${\pi }^{+}{\pi }^{-}{\pi }^0$, $K^{+}{K}^{-}$, $K_L{K}_S$ and of the dipion spectrum in the decay ${\tau }^{\pm }\to {\pi }^{\pm }{\pi }^0\nu$ can be performed. Supplemented with a few pieces of information on the ${\rho }^0-\omega -\varphi$ system, the $\tau$ dipion spectrum is shown to predict accurately the pion form factor in $e^{+}{e}^{-}$ annihilations. Physics results derived from global fits involving or excluding the $\tau$ dipion spectra are found consistent with each others. Therefore, no obvious mismatch between the $\tau$ and $e^{+}{e}^{-}$ physics properties arises and the $\tau -e^{+}{e}^{-}$ puzzle vanishes within the broken HLS Model.

    hep-phhep-exEPJ Web Conf.(2016)·9 citations
12. 12*

    Glueball decay patterns in top-down holographic QCD

    Frederic Brünner🇦🇹 · Denis Parganlija🇦🇹 · Anton Rebhan🇦🇹

    We discuss our results on scalar glueball decay in the top-down holographic Witten-Sakai-Sugimoto model for low-energy QCD and compare with available experimental data, which appear to disfavor the glueball candidate $f_0(1500)$ but seem to be perfectly consistent with interpreting $f_0(1710)$ as a nearly unmixed glueball. The holographic model moreover makes definite predictions for future experiments.

    hep-phnucl-thPoS(2015)·3 citations
13. 13*

    Syzygies Probing Scattering Amplitudes

    Gang Chen🇨🇳 · Junyu Liu🇨🇳 · Ruofei Xie🇨🇳 · Hao Zhang🇨🇳 · Yehao Zhou🇨🇳

    We propose a new efficient algorithm to obtain the locally minimal generating set of the syzygies for an ideal, i.e. a generating set whose proper subsets cannot be generating sets. Syzygy is a concept widely used in the current study of scattering amplitudes. This new algorithm can deal with more syzygies effectively because a new generation of syzygies is obtained in each step and the irreducibility of this generation is also verified in the process. This efficient algorithm can also be applied in getting the syzygies for the modules. We also show a typical example to illustrate the potential application of this method in scattering amplitudes, especially the Integral-By-Part(IBP) relations of the characteristic two-loop diagrams in the Yang-Mills theory.

    ↳ hep-thhep-phmath-phmath.MPJHEP(2016)·18 citations
14. 14*

    Integration-by-parts reductions from unitarity cuts and algebraic geometry

    Kasper J. Larsen🇨🇭 · Yang Zhang🇨🇭

    We show that the integration-by-parts reductions of various two-loop integral topologies can be efficiently obtained by applying unitarity cuts to a specific set of subgraphs and solving associated polynomial (syzygy) equations.

    ↳ hep-thhep-phPRD(2016)·268 citations
15. 15*

    Green's function approach to Chern-Simons extended electrodynamics: an effective theory describing topological insulators

    A. Martín-Ruiz🇲🇽 · M. Cambiaso🇨🇱 · L. F. Urrutia🇲🇽

    Boundary effects produced by a Chern-Simons (CS) extension to electrodynamics are analyzed exploiting the Green's function (GF) method. We consider the electromagnetic field coupled to a $\theta$-term in a way that has been proposed to provide the correct low energy effective action for topological insulators (TI). We take the $\theta$-term to be piecewise constant in different regions of space separated by a common interface $\Sigma$, to be called the $\theta$-boundary. Features arising due to the presence of the boundary, such as magnetoelectric effects, are already known in CS extended electrodynamics and solutions for some experimental setups have been found with specific configuration of sources. In this work we illustrate a method to construct the GF that allows to solve the CS modified field equations for a given $\theta$-boundary with otherwise arbitrary configuration of sources. The method is illustrated by solving the case of a planar $\theta$-boundary but can also be applied for cylindrical and spherical geometries for which the $\theta$-boundary can be characterized by a surface where a given coordinate remains constant. The static fields of a point-like charge interacting with a planar TI, as described by a planar discontinuity in $\theta$, are calculated and successfully compared with previously reported results. We also compute the force between the charge and the $\theta$-boundary by two different methods, using the energy momentum tensor approach and the interaction energy calculated via the GF. The infinitely straight current-carrying wire is also analyzed.

    ↳ cond-mat.otherhep-phhep-thPRD(2015)·57 citations
16. 16*

    The effect of entanglement in gravitational photon-photon scattering

    Dennis Rätzel🇩🇪 · Martin Wilkens🇩🇪 · Ralf Menzel🇩🇪

    The differential cross section for gravitational photon-photon scattering calculated in Perturbative Quantum Gravity is shown to depend on the degree of polarization entanglement of the two photons. The interaction between photons in the symmetric Bell state is stronger than between not entangled photons. In contrast, the interaction between photons in the anti-symmetric Bell state is weaker than between not entangled photons. The results are interpreted in terms of quantum interference, and it is shown how they fit into the idea of distance-dependent forces.

    ↳ quant-phgr-qchep-phhep-thEPL(2016)·7 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.