Thu·Jul 21, 2016Thursday·July 21, 2016

1. 01*

   Splitting Mass Spectra and Muon g-2 in Higgs-Anomaly Mediation

   Wen Yin🇯🇵 · Norimi Yokozaki🇯🇵

   We propose a scenario where only the Higgs multiplets have direct couplings to a supersymmetry (SUSY) breaking sector. The standard model matter multiplets as well as the gauge multiples are sequestered from the SUSY breaking sector; therefore, their masses arise via anomaly mediation at the high energy scale with a gravitino mass of $\sim$100 TeV. Due to renormalization group running effects from the Higgs soft masses, the masses of the third generation sfermions become O(10) TeV at the low energy scale, while the first and second generation sfermion masses are O(0.1-1) TeV, avoiding the tachyonic slepton problem and flavor changing neutral current problem. With the splitting mass spectrum, the muon g-2 anomaly is explained consistently with the observed Higgs boson mass of 125 GeV. Moreover, the third generation Yukawa couplings are expected to be unified in some regions.

   hep-phhep-exPLB(2016)·51 citations
2. 02*

   On light baryons and their excitations

   Gernot Eichmann🇩🇪 · Christian S. Fischer🇩🇪 · Helios Sanchis-Alepuz🇦🇹

   We study ground states and excitations of light octet and decuplet baryons within the framework of Dyson-Schwinger and Faddeev equations. We improve upon similar approaches by explicitly taking into account the momentum-dependent dynamics of the quark-gluon interaction that leads to dynamical chiral symmetry breaking. We perform calculations in both the three-body Faddeev framework and the quark-diquark approximation in order to assess the impact of the latter on the spectrum. Our results indicate that both approaches agree well with each other. The resulting spectra furthermore agree one-to-one with experiment, provided well-known deficiencies of the rainbow-ladder approximation are compensated for. We also discuss the mass evolution of the Roper and the excited Delta with varying pion mass and analyse the internal structure in terms of their partial wave decompositions.

   hep-phnucl-thPRD(2016)·88 citations
3. 03*

   Chiral Phase Transition and Meson Melting from AdS/QCD

   Sean P. Bartz🇺🇸 · Theodore Jacobson🇺🇸

   We investigate the in-medium behavior of mesons at finite temperature and baryon chemical potential within a soft-wall model of AdS/QCD. We use a quartic scalar potential to obtain the correct form of chiral symmetry breaking. At zero quark mass the chiral phase transition is second-order, becoming a crossover at physical quark mass. At zero baryon chemical potential, we find a chiral transition temperature of 155 MeV in the chiral limit and a pseudo-transition temperature of 151 MeV at physical quark mass, consistent with lattice results. In the low-temperature limit, the second-order transition occurs at a baryon chemical potential of 566 MeV while the rapid crossover occurs at 559 MeV. A new parameterization of the dilaton profile results in improved meson spectra. Meson melting occurs at a lower temperature and chemical potential than the chiral phase transition, so the vector-axial vector mass splitting remains constant until the bound states melt.

   hep-phPRD(2016)·43 citations
4. 04*

   On the thermodynamically consistent quasiparticle model of quark gluon plasma

   Guru Prakash Kadam🇮🇳

   We give the alternative formulation of quasiparticle model of quark gluon plasma with medium dependent dispersion relation. The model is thermodynamically consistent provided the medium dependent contribution to the energy density is taken in to account. We establish the connection of our model with other variants of quasiparticle models which are thermodynamically consistent. We test the model by comparing the equation of state with the lattice gauge theory simulations of SU(3) pure gluodynamics .

   hep-phnucl-th0 citations
5. 05*

   Physics of Higgs Boson Family

   Ngee-Pong Chang🇺🇸

   In the Standard Model, there is the single Higgs field, $\varphi$, which gives rise to constituent quark and lepton masses. The Yukawa coupling is a highly complex set of $3\times 3$ matrices, resulting in many textures of quark and lepton masses. In this talk, I present a model which transfers the complexity of the Yukawa coupling matrices to a family of Higgs fields, so that the Yukawa coupling itself becomes a simple interaction. In the context of this Enriched Standard Model, we introduce a new $r$-symmetry in the extended $SU(2{)}_L\times U(1{)}_Y\times U(1{)}_R$ model and show how the $125GeV$ and $750GeV$ resonances may be identified with $H$ and $H^{\prime }$, the key members of the Higgs family, with $H$ being in every way identifed with the SM Higgs. There are interesting consequences of their $2\gamma$ decay widths.

   hep-ph0 citations
6. 06*

   tWH associated production at the LHC

   Federico Demartin🇧🇪 · Benedikt Maier🇺🇸 · Fabio Maltoni🇧🇪 · Kentarou Mawatari🇫🇷 · Marco Zaro🇫🇷

   We study Higgs boson production in association with a top quark and a $W$ boson at the LHC. At NLO in QCD, $tWH$ interferes with $t\bar{t}H$ and a procedure to meaningfully separate the two processes needs to be employed. In order to define $tWH$ production for both total rates and differential distributions, we consider the diagram removal and diagram subtraction techniques that have been previously proposed for treating intermediate resonances at NLO, in particular in the context of $tW$ production. These techniques feature approximations that need to be carefully taken into account when theoretical predictions are compared to experimental measurements. To this aim, we first critically revisit the $tW$ process, for which an extensive literature exists and where an analogous interference with $t\bar{t}$ production takes place. We then provide robust results for total and differential cross sections for $tW$ and $tWH$ at 13 TeV, also matching short-distance events to a parton shower. We formulate a reliable prescription to estimate the theoretical uncertainties, including those associated to the very definition of the process at NLO. Finally, we study the sensitivity to a non-Standard-Model relative phase between the Higgs couplings to the top quark and to the $W$ boson in $tWH$ production.

   hep-phEPJC(2017)·200 citations
7. 07*

   Tests of CPT symmetry in B0-B0bar mixing and in B0 to c cbar K0 decays

   Klaus R. Schubert🇩🇪

   Using the time dependences for the decays Y(4S) to B0B0bar to (ell^+- X)(c cbar K_S,L), we determine the three CPT-sensitive parameters Re (z) and Im (z) in B0-B0bar mixing and |Abar/A| in B0 to c cbar K0 decays. We find Im(z) = 0.010 +- 0.030 +- 0013, Re(z) = -0:065 +- 0.028 +- 0.014, and |Abar/A| = 0.999 +- 0.023 +- 0.017, in agreement with CPT symmetry. The Re(z) result provides a limit on one component of Lorentz-symmetry violation.

   hep-ph11 citations
8. 08*

   Isoscalar $\pi \pi$ scattering and the $\sigma$ meson resonance from QCD

   Raul A. Briceno🇺🇸 · Jozef J. Dudek🇺🇸 · Robert G. Edwards🇺🇸 · David J. Wilson🇬🇧

   We present for the first time a determination of the energy dependence of the isoscalar $\pi \pi$ elastic scattering phase-shift within a first-principles numerical lattice approach to QCD. Hadronic correlation functions are computed including all required quark propagation diagrams, and from these the discrete spectrum of states in the finite volume defined by the lattice boundary is extracted. From the volume dependence of the spectrum we obtain the $S$-wave phase-shift up to the $K\overline{K}$ threshold. Calculations are performed at two values of the $u,d$ quark mass corresponding to $m_{\pi }=236,391$ MeV and the resulting amplitudes are described in terms of a $\sigma$ meson which evolves from a bound-state below $\pi \pi$ threshold at the heavier quark mass, to a broad resonance at the lighter quark mass.

   hep-phhep-latPRL(2017)·235 citations
9. 09*

   FCNC decays of SM fermions into a dark photon

   Emidio Gabrielli🇮🇹 · Barbara Mele🇮🇹 · Martti Raidal🇪🇪 · Elena Venturini🇮🇹

   We analyze a new class of FCNC processes, the $f\to f^{\prime }\bar{\gamma }$ decays of a fermion $f$ into a lighter (same-charge) fermion $f^{\prime }$ plus a {\it massless} neutral vector boson, a {\it dark photon} $\bar{\gamma }$. A massless dark photon does not interact at tree level with observable fields, and the $f\to f^{\prime }\bar{\gamma }$ decay presents a characteristic signature where the final fermion $f^{\prime }$ is balanced by a {\it massless invisible} system. Models recently proposed to explain the exponential spread in the standard-model Yukawa couplings can indeed foresee an extra unbroken {\it dark} $U(1)$ gauge group, and the possibility to couple on-shell dark photons to standard-model fermions via one-loop magnetic-dipole kind of FCNC interactions. The latter are suppressed by the characteristic scale related to the mass of heavy messengers, connecting the standard model particles to the dark sector. We compute the corresponding decay rates for the top, bottom, and charm decays ($t\to c\bar{\gamma },u\bar{\gamma }$, $b\to s\bar{\gamma },d\bar{\gamma }$, and $c\to u\bar{\gamma }$), and for the charged-lepton decays ($\tau \to \mu \bar{\gamma },e\bar{\gamma }$, and $\mu \to e\bar{\gamma }$) in terms of model parameters. We find that large branching ratios for both quark and lepton decays are allowed in case the messenger masses are in the discovery range of the LHC. Implications of these new decay channels at present and future collider experiments are briefly discussed.

   hep-phhep-exPRD(2016)·52 citations
10. 10*

    Testing Lorentz Symmetry using Chiral Perturbation Theory

    J.P. Noordmans🇵🇹

    We consider the low-energy effects of a selected set of Lorentz- and CPT-violating quark and gluon operators by deriving the corresponding chiral effective lagrangian. Using this effective lagrangian, low-energy hadronic observables can be calculated. We apply this to magnetometer experiments and derive the best bounds on some of the Lorentz-violating coefficients. We point out that progress can be made by studying the nucleon-nucleon potential, and by considering storage-ring experiments for deuterons and other light nuclei.

    hep-phnucl-th0 citations
11. 11*

    Quark-Gluon tagging with Shower Deconstruction: Unearthing dark matter and Higgs couplings

    Danilo Ferreira de Lima🇩🇪 · Petar Petrov🇬🇧 · Davison Soper🇺🇸 · Michael Spannowsky🇬🇧

    The separation of quark and gluon initiated jets can be an important way to improve the sensitivity in searches for new physics or in measurements of Higgs boson properties. We present a simplified version of the shower deconstruction approach as a novel observable for quark-gluon tagging. Assuming topocluster-like objects as input, we compare our observable with energy correlation functions and find a favorable performance for a large variety of jet definitions. When applied to dark matter searches in mono-jet final states limitations from small signal-to-background ratios can be overcome. We also show that quark-gluon tagging is an alternative way of separating weak boson from gluon-fusion production in the process p + p -> H + jet + jet + X

    hep-phhep-exPRD(2017)·58 citations
12. 12*

    Analytical parametrization and shape classification of anomalous HH production in the EFT approach

    Alexandra Carvalho🇮🇹 · Martino Dall'Osso🇮🇹 · Pablo de Castro Manzano🇮🇹 · Tommaso Dorigo🇮🇹 · Florian Goertz🇨🇭 · Maxime Gouzevich🇫🇷 · Mia Tosi🇨🇭

    In this document we study the effect of anomalous Higgs boson couplings on non-resonant pair production of Higgs bosons ($HH$) at the LHC. We explore the space of the five parameters ${\kappa }_{\lambda }$, ${\kappa }_t$, $c_2$, $c_g$, and $c_{2g}$ in terms of the corresponding kinematics of the final state, and describe a partition of the space into a limited number of regions featuring similar phenomenology in the kinematics of $HH$ final state. We call clusters the sets of points belonging to the same region; to each cluster corresponds a representative point which we call a benchmark. We discuss a possible technique to estimate the sensitivity of an experimental search to the kinematical differences between the phenomenology of the benchmark points and the rest of the parameter space contained in the corresponding cluster. We also provide an analytical parametrization of the cross-section modifications that the variation of anomalous couplings produces with respect to standard model $HH$ production along with a recipe to translate the results into other parameter-space bases. Finally, we provide a preliminary analysis of variations in the topology of the final state within each region based on recent LHC results.

    hep-phhep-ex43 citations
13. 13*

    Ultra-High Energy Astrophysical Neutrino Detection, and the Search for Lorentz Invariance Violations

    J.C. Hanson🇺🇸

    A growing class of ultra-high energy neutrino (UHE-nu) observatories based on the Askaryan effect and Antarctic ice is able to search for Lorentz invariance violation (LIV). The ARA, ARIANNA, ANITA and EVA collaborations have the power to constrain the Standard Model Extension (SME) by measuring the flux and energy distribution of neutrinos created through the GZK process. The future expansion of ARA, at the South Pole, pushes the discovery potential further.

    ↳ astro-ph.HEhep-ph0 citations
14. 14*

    Axions And Self-Interacting Dark Matter In The Heterotic String-Derived Model

    Johar M. Ashfaque🇬🇧

    After revisiting the heterotic string-derived low-energy effective model of \cite{Ashfaque:2016ydg, Athanasopoulos:2014bba, Faraggi:2016xnm, Ashfaque:2016jha} constructed in the four-dimensional free fermionic formulation, we find two axions which are either harmful or massive. As a direct consequence, they can not solve the strong $CP$ problem which is in complete agreement with \cite{Lopez:1990iq, Halyo:1993xn}. We also explore the possibility of the self-interacting dark matter residing in the non-Abelian gauge group present in the hidden sector \cite{Faraggi:2000pv}. We find that the low-energy string-derived model naturally welcomes the self-interacting dark matter as $4$ copies of the non-Abelian, hidden $SU(2)$ gauge group factor are present.

    ↳ physics.gen-phhep-ph2 citations
15. 15*

    Musings on Lorentz Violation Given the Recent Gravitational-Wave Observations of Coalescing Binary Black Holes

    Nicolas Yunes🇺🇸

    The recent observation of gravitational waves by the LIGO/Virgo collaboration provides a unique opportunity to probe the extreme gravity of coalescing binary black holes. In this regime, the gravitational interaction is not only strong, but the spacetime curvature is large, characteristic velocities are a non-negligible fraction of the speed of light, and the time scale on which the curvature and gravity change is small. This contribution discusses some consequences of these observations on modifications to General Relativity, with a special emphasis on Lorentz-violating theories.

    ↳ gr-qchep-ph1 citation
16. 16*

    Measurement of the CKM angle ${\phi }_1$ in $B^0\to \bar{D}{}^{(\ast )0}{h}^0$, $\bar{D}{}^0\to K_S^0{\pi }^{+}{\pi }^{-}$ decays with time-dependent binned Dalitz plot analysis

    Belle Collaboration: V. Vorobyev🇷🇺 · I. Adachi🇯🇵 · H. Aihara🇯🇵 · D. M. Asner🇺🇸 · T. Aushev🇷🇺 · R. Ayad🇸🇦 · I. Badhrees🇸🇦 · S. Bahinipati🇮🇳 · A. M. Bakich🇦🇺 · P. Behera🇮🇳 · V. Bhardwaj🇮🇳 · B. Bhuyan🇮🇳 and 153 other authors

    We report a measurement of the CP violation parameter ${\phi }_1$ obtained in a time-dependent analysis of $B^0\to \bar{D}{}^{(\ast )0}{h}^0$ decays followed by $\bar{D}{}^0\to K_S^0{\pi }^{+}{\pi }^{-}$ decay. A model-independent measurement is performed using the binned Dalitz plot technique. The measured value is ${\phi }_1=11.7^{\circ }\pm 7.8^{\circ }(stat.)\pm 2.1^{\circ }(syst.)$. Treating $\sin 2{\phi }_1$ and $\cos 2{\phi }_1$ as independent parameters, we obtain $\sin 2{\phi }_1=0.43\pm 0.27(stat.)\pm 0.08(syst.)$ and $\cos 2{\phi }_1=1.06\pm 0.33(stat.{)}_{-0.15}^{+0.21}(syst.)$. The results are obtained with a full data sample of $772\times 10^{6}B\bar{B}$ pairs collected near the ${\rm Y}(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider.

    ↳ hep-exhep-phPRD(2016)·23 citations
17. 17*

    Structure of the $\mathbf{\Lambda }(1405)$ from Hamiltonian effective field theory

    Zhan-Wei Liu🇦🇺 · Jonathan M. M. Hall🇦🇺 · Derek B. Leinweber🇦🇺 · Anthony W. Thomas🇦🇺 · Jia-Jun Wu🇦🇺

    The pole structure of the $\Lambda (1405)$ is examined by fitting the couplings of an underlying Hamiltonian effective field theory to cross sections of $K^{-}p$ scattering in the infinite-volume limit. Finite-volume spectra are then obtained from the theory, and compared to lattice QCD results for the mass of the $\Lambda (1405)$. Momentum-dependent, non-separable potentials motivated by the well-known Weinberg-Tomozawa terms are used, with SU(3) flavour symmetry broken in the couplings and masses. In addition, we examine the effect on the behaviour of the spectra from the inclusion of a bare triquark-like isospin-zero basis state. It is found that the cross sections are consistent with the experimental data with two complex poles for the $\Lambda (1405)$, regardless of whether a bare baryon basis state is introduced or not. However, it is apparent that the bare baryon is important for describing the results of lattice QCD at high pion masses.

    ↳ nucl-thhep-lathep-phPRD(2017)·83 citations
18. 18*

    Predicting the singlet vector channel in a partially Higgsed gauge theory

    A. Maas🇦🇹 · P. Törek🇦🇹

    We study a toy version of a grand-unified theory on the lattice: An $SU(3)$ gauge theory, which experiences a Brout-Englert-Higgs effect due to a single Higgs field in the fundamental representation. This yields a perturbative breaking pattern $SU(3)\to SU(2)$. We investigate the singlet vector channel, finding an apparently non-degenerate and massive ground state. This is in contradistinction to the perturbative prediction of three massless and five massive vector states, even though the correlation functions of the gauge bosons exhibit a weak-coupling behavior, being almost tree-level-like. However, a combination of perturbation theory with the Fröhlich-Morchio-Strocchi mechanism allows to predict the physical spectrum in this channel.

    ↳ hep-lathep-phhep-thPRD(2017)·37 citations
19. 19*

    Gauge Symmetries Emerging from Extra Dimensions

    J.L. Chkareuli🇬🇪 · Z. Kepuladze🇬🇪

    We argue that extra dimensions with a properly chosen compactification scheme could be a natural source for emergent gauge symmetries. Actually, some proposed vector field potential terms or polynomial vector field constraints introduced in five-dimensional Abelian and non-Abelian gauge theory is shown to smoothly lead to spontaneous violation of an underlying 5D spacetime symmetry and generate pseudo-Goldstone vector modes as conventional 4D gauge boson candidates. As a special signature, there appear, apart from conventional gauge couplings, some properly suppressed direct multi-photon (multi-boson, in general) interactions in emergent QED and Yang-Mills theories whose observation could shed light on their high-dimensional nature. Moreover, in emergent Yang-Mills theories an internal symmetry G also occurs spontaneously broken to its diagonal subgroups once 5D Lorentz violation happens. This breaking origins from the extra vector field components playing a role of some adjoint scalar field multiplet in the 4D spacetime. So, one naturally has the Higgs effect without a specially introduced scalar field multiplet. Remarkably, when being applied to Grand Unified Theories this results in a fact that the emergent GUTs generically appear broken down to the Standard Model just at the 5D Lorentz violation scale M. PACS numbers: 11.15.-q, 11.30.Cp, 11.30.Pb, 11.10.Kk

    ↳ hep-thhep-phPRD(2016)·1 citation
20. 20*

    Neutrino Flavor Evolution in Binary Neutron Star Merger Remnants

    Maik Frensel🇨🇭 · Meng-Ru Wu🇩🇪 · Cristina Volpe🇫🇷 · Albino Perego🇩🇪

    We study the neutrino flavor evolution in the neutrino-driven wind from a binary neutron star merger remnant consisting of a massive neutron star surrounded by an accretion disk. With the neutrino emission characteristics and the hydrodynamical profile of the remnant consistently extracted from a three-dimensional simulation, we compute the flavor evolution by taking into account neutrino coherent forward scattering off ordinary matter and neutrinos themselves. We employ a "single-trajectory" approach to investigate the dependence of the flavor evolution on the neutrino emission location and angle. We also show that the flavor conversion in the merger remnant can affect the (anti-)neutrino absorption rates on free nucleons and may thus impact the $r$-process nucleosynthesis in the wind. We discuss the sensitivity of such results on the change of neutrino emission characteristics, also from different neutron star merger simulations.

    ↳ astro-ph.HEhep-phPRD(2017)·67 citations
21. 21*

    Twist-2 at seven loops in planar N=4 SYM theory: Full result and analytic properties

    Christian Marboe🇮🇪 · Vitaly Velizhanin🇩🇪

    The anomalous dimension of twist-2 operators of arbitrary spin in planar N=4 SYM theory is found at seven loops by using the quantum spectral curve to compute values at fixed spin, and reconstructing the general result using the LLL-algorithm together with modular arithmetic. The result of the analytic continuation to negative spin is presented, and its relation with the recently computed correction to the BFKL and double-logarithmic equation is discussed.

    ↳ hep-thhep-phJHEP(2016)·55 citations
22. 22*

    Universal features of quantum bounce in loop quantum cosmology

    Tao Zhu🇨🇳 · Anzhong Wang🇨🇳 · Klaus Kirsten🇺🇸 · Gerald Cleaver🇺🇸 · Qin Sheng🇺🇸

    In this Letter, we study analytically the evolutions of the flat Friedmann-Lemaitre-Robertson-Walker (FLRW) universe and its linear perturbations in the framework of {\em the dressed metric approach} in loop quantum cosmology (LQC). Assuming that the evolution of the background is dominated by the kinetic energy of the inflaton at the quantum bounce, we find that both evolutions of the background and its perturbations are independent of the inflationary potentials during the pre-inflationary phase. During this period the effective potentials of the perturbations can be well approximated by a Pöschl-Teller (PT) potential, from which we find analytically the mode functions and then calculate the corresponding Bogoliubov coefficients at the onset of the slow-roll inflation, valid for any inflationary model with a single scalar field. Imposing the Bunch-Davies (BD) vacuum in the contracting phase prior to the bounce when the modes are all inside the Hubble horizon, we show that particles are generically created due to the pre-inflation dynamics. Matching them to those obtained in the slow-roll inflationary phase, we investigate the effects of the pre-inflation dynamics on the scalar and tensor power spectra and find features that can be tested by current and forthcoming observations. In particular, to be consistent with the Planck 2015 data, we find that the universe must have expanded at least $141$ e-folds since the bounce.

    ↳ gr-qcastro-ph.COhep-phhep-thPLB(2017)·66 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.