Wed·Feb 22, 2017Wednesday·February 22, 2017

1. 01*

   Search for right-handed neutrinos from dark matter annihilation with gamma-rays

   Miguel D. Campos🇩🇪 · Farinaldo S. Queiroz🇩🇪 · Carlos E. Yaguna🇩🇪 · Christoph Weniger🇳🇱

   Several extensions of the Standard Model contain right-handed (sterile) neutrinos in the GeV-TeV mass range. Due to their mixing with the active neutrinos, they may give rise to novel effects in cosmology, neutrino physics, and collider searches. In addition, right-handed neutrinos can also appear as final states from dark matter annihilations, with important implications for dark matter indirect detection searches. In this paper, we use current data from the Fermi Large Area Telescope (6-year observation of dwarf spheroidal galaxies) and H.E.S.S. (10-year observation of the Galactic center) to constrain the annihilation of dark matter into right-handed neutrinos. We consider right-handed neutrino with masses between 10 GeV and 1 TeV, including both two-body and three-body decays, to derive bounds on the dark matter annihilation rate, $⟨\sigma v⟩$, as a function of the dark matter mass. Our results show, in particular, that the thermal dark matter annihilation cross section, $3\times 10^{-26}\mathrm{c}{\mathrm{m}}^3{\mathrm{s}}^{-1}$, into right-handed neutrinos is excluded for dark matter masses smaller than $200$ GeV.

   hep-phastro-ph.HEJCAP(2017)·45 citations
2. 02*

   Pair production of the Elementary Goldstone Higgs boson at the LHC

   Chong-Xing Yue🇨🇳 · Lu Ma🇨🇳 · Ya-bing Zuo🇨🇳 · Yu-chen Guo🇨🇳

   The Elementary Goldstone Higgs (EGH) model is a perturbative extension of the standard model (SM), which identifies the EGH boson as the observed Higgs boson. In this paper, we study pair production of the EGH boson via gluon fusion at the LHC and find that the resonant contribution of the heavy scalar is very small and the SM-like triangle diagram contribution is strongly suppressed. The total production cross section mainly comes from the box diagram contribution and its value can be significantly enhanced with respect to the SM prediction.

   hep-phCPC(2017)·1 citation
3. 03*

   Aspects of open-flavour mesons in a comprehensive DSBSE study

   T. Hilger🇦🇹 · M. Gómez-Rocha🇮🇹 · A. Krassnigg🇦🇹 · W. Lucha🇦🇹

   Open-flavour meson studies are the necessary completion to any comprehensive investigation of quarkonia. We extend recent studies of quarkonia in the Dyson-Schwinger-Bethe-Salpeter-equation approach to explore their results for all possible flavour combinations. Within the inherent limitations of the setup, we present the most comprehensive results for meson masses and leptonic decay constants currently available and put them in perspective with respect to experiment and other approaches.

   hep-phEPJA(2017)·47 citations
4. 04*

   A toy model of elastic scattering of high energy protons

   I.M. Dremin🇷🇺

   The ratio of elastic to total proton cross sections is related to the darkness of the spatial profile of inelastic interactions by a single parameter in the framework of a simple analytical model. Their critical values at LHC energies are discussed. Two possible variants of their asymptotical behavior are described.

   hep-phhep-exnucl-exnucl-th5 citations
5. 05*

   Including resummation in the NLO BK equation

   T. Lappi🇫🇮 · H. Mäntysaari🇺🇸

   We include a resummation of large transverse momentum logarithms in the next-to-leading order (NLO) Balitsky-Kovchegov equation. The resummed evolution equation is shown to be stable, the evolution speed being significantly reduced by NLO corrections. The contributions from NLO terms that are not enhanced by large logarithms are found to be numerically important close to phenomenologically relevant initial conditions. We numerically determine the value for the constant in the resummed logarithm that includes a maximal part of the full NLO terms in the resummation.

   hep-phnucl-thNucl.Part.Phys.Proc.(2017)·0 citations
6. 06*

   Parton-to-Kaon Fragmentation Revisited

   D. de Florian🇦🇷 · M. Epele🇦🇷 · R. J. Hernandez-Pinto🇲🇽 · R. Sassot🇦🇷 · M. Stratmann🇩🇪

   We revisit the global QCD analysis of parton-to-kaon fragmentation functions at next-to-leading order accuracy using the latest experimental information on single-inclusive kaon production in electron-positron annihilation, lepton-nucleon deep-inelastic scattering, and proton-proton collisions. An excellent description of all data sets is achieved, and the remaining uncertainties in parton-to-kaon fragmentation functions are estimated and discussed based on the Hessian method. Extensive comparisons to the results from our previous global analysis are made.

   hep-phPRD(2017)·148 citations
7. 07*

   The leptonic widths of high $\psi$-resonances in unitary coupled-channel model

   A.M. Badalian🇷🇺 · B.L.G. Bakker🇳🇱

   The leptonic widths of high $\psi$-resonances are calculated in a coupled-channel model with unitary inelasticity, where analytical expressions for mixing angles between $(n+1){}^3{S}_1$ and $n{}^3{D}_1$ states and probabilities $Z_i$ of the $c\bar{c}$ component are derived. Since these factors depend on energy (mass), different values of mixing angles $\theta (\psi (4040))=27.7^{\circ }$ and $\theta (\psi (4160))=29.5^{\circ }$, $Z_1(\psi (4040))=0.76$, and $Z_2(\psi (4160))=0.62$ are obtained. It gives the leptonic widths ${\Gamma }_{ee}(\psi (4040))=Z_{1}1.17=0.89$~keV, ${\Gamma }_{ee}(\psi (4160))=Z_{2}0.76=0.47$~keV in good agreement with experiment. For $\psi (4415)$ the leptonic width ${\Gamma }_{ee}(\psi (4415))=0.55$~keV is calculated, while for the missing resonance $\psi (4510)$ we predict $M(\psi (4500))=(4515\pm 5)$~MeV and ${\Gamma }_{ee}(\psi (4510))\cong 0.50$~keV.

   hep-phhep-exPRD(2017)·7 citations
8. 08*

   Unification with Vector-like fermions and signals at LHC

   Biplob Bhattacherjee🇮🇳 · Pritibhajan Byakti🇮🇳 · Ashwani Kushwaha🇮🇳 · Sudhir K Vempati🇮🇳

   We look for minimal extensions of Standard Model with vector like fermions leading to precision unification of gauge couplings. Constraints from proton decay, Higgs stability and perturbativity are considered. The simplest models contain several copies of vector fermions in two different (incomplete) representations. Some of these models encompass Type III seesaw mechanism for neutrino masses whereas some others have a dark matter candidate. In all the models, at least one of the candidates has non-trivial representation under $SU(3{)}_{color}$. In the limit of vanishing Yukawa couplings, new QCD bound states are formed, which can be probed at LHC. The present limits based on results from 13 TeV already probe these particles for masses around a TeV. Similar models can be constructed with three or four vector representations, examples of which are presented.

   hep-phJHEP(2018)·21 citations
9. 09*

   Chiral magnetic effect in the presence of electroweak interactions as a quasiclassical phenomenon

   Maxim Dvornikov (1 and 2)🇷🇺 · Victor B. Semikoz (1) ((1) IZMIRAN, (2) Tomsk State University)🇷🇺

   We elaborate the quasiclassical approach to obtain the modified chiral magnetic effect in the case when massless charged fermions interact with electromagnetic fields and the background matter by the electroweak forces. The derivation of the anomalous current along the external magnetic field involves the study of the energy density evolution of chiral particles in parallel electric and magnetic fields. We consider both the particle acceleration by the external electric field and the contribution of the Adler anomaly. The condition of the validity of this method for the derivation of the chiral magnetic effect is formulated. We obtain the expression for the electric current along the external magnetic field, which appears to coincide with our previous results based on the purely quantum approach. Our results are compared with findings of other authors.

   hep-phastro-ph.HEhep-thMod.Phys.Lett.A(2018)·4 citations
10. 10*

    Effect of systematics in the T2HK, T2HKK, and DUNE experiments

    Monojit Ghosh🇯🇵 · Osamu Yasuda🇯🇵

    T2HK and T2HKK are the proposed extensions of the of T2K experiments in Japan and DUNE is the future long-baseline program of Fermilab. All these three experiments will use extremely high beam power and large detector volumes to observe neutrino oscillation. Because of the large statistics, these experiments will be highly sensitive to systematics. Thus a small change in the systematics can cause a significant change in their sensitivities. To understand this, we do a comparative study of T2HK, T2HKK and DUNE with respect to their systematic errors. Specifically we study the effect of the systematics in the determination of neutrino mass hierarchy, octant of the mixing angle ${\theta }_{23}$ and ${\delta }_{CP}$ in the standard three flavor scenario and also analyze the role of systematic uncertainties in constraining the parameters of the nonstandard interactions in neutrino propagation. Taking the overall systematics for signal and background normalization, we quantify how the sensitivities of these experiments change if the systematics are varied from $1\%$ to $7\%$.

    hep-phPRD(2017)·38 citations
11. 11*

    Double hard scattering without double counting

    Markus Diehl🇩🇪 · Jonathan R. Gaunt🇳🇱 · Kay Schönwald🇩🇪

    Double parton scattering in proton-proton collisions includes kinematic regions in which two partons inside a proton originate from the perturbative splitting of a single parton. This leads to a double counting problem between single and double hard scattering. We present a solution to this problem, which allows for the definition of double parton distributions as operator matrix elements in a proton, and which can be used at higher orders in perturbation theory. We show how the evaluation of double hard scattering in this framework can provide a rough estimate for the size of the higher-order contributions to single hard scattering that are affected by double counting. In a numeric study, we identify situations in which these higher-order contributions must be explicitly calculated and included if one wants to attain an accuracy at which double hard scattering becomes relevant, and other situations where such contributions may be neglected.

    hep-phJHEP(2017)·77 citations
12. 12*

    Qbe: Quark Matter on Rubik's Cube

    T. Csörgő🇭🇺

    Quarks can be represented on the faces of the 3x3 Rubik's cube with the help of a symbolic representation of quarks and anti-quarks, that was delevoped originally for a deck of elementary particle cards, called Quark Matter Card Game. Cubing the cards leads to a model of the nearly perfect fluid of Quark Matter on Rubik's cube, or Qbe, which can be utilized to provide hands-on experience with the high entropy density, overall color neutrality and net baryon free, nearly perfect fluid nature of Quark Matter.

    ↳ physics.pop-phhep-exhep-phnucl-ex+1JCEGI 4 (4) pp. 210-223 (2016)·1 citation
13. 13*

    Some Astrophysical Aspects of a Schwarzschild Geometry Equipped with a Minimal Measurable Length

    Mohsen Khodadi🇮🇷 · Kourosh Nozari🇮🇷 · Anahita Hajizadeh🇮🇷

    By considering a deformation of the Schwarzschild metric in the presence of a minimal measurable length which still respects the equivalence principle, we study corrections to the standard general relativistic predictions for some astrophysical phenomena such as stability of circular orbits of black hole accretion disks, redshift of black hole accretion disks, gravitational tidal forces and the geodetic drift rate. We use the \emph{Gravity Probe B} data to see robustness of our results. Our analysis shows also that the relevant deformation parameter $\epsilon$ which has a geometric origin, plays the same role as the charge to mass ratio, $\frac{e}{m}$ in the Reissner-Nordström metric.

    ↳ gr-qchep-phhep-thPLB(2017)·23 citations
14. 14*

    Matrix Model of QCD: Edge Localized Glue Balls and Phase Transitions

    Nirmalendu Acharyya🇧🇪 · A. P. Balachandran🇺🇸

    In a matrix model of pure $SU(2)$ Yang-Mills theory, boundaries emerge in the space of ${\text{Mat}}_3(\mathbb{R})$ and the Hamiltonian requires boundary conditions. We show the existence of edge localized glueball states which can have negative energies. These edge levels can be lifted to positive energies if the gluons acquire a London-like mass. This suggests a new phase of QCD with an incompressible bulk.

    ↳ hep-thhep-phmath-phmath.MPPRD(2017)·7 citations
15. 15*

    Large mass hierarchies from strongly-coupled dynamics

    Andreas Athenodorou🇨🇾 · Ed Bennett🇬🇧 · Georg Bergner🇨🇭 · Daniel Elander🇿🇦 · C.-J. David Lin🇹🇼 · Biagio Lucini🇬🇧 · Maurizio Piai🇬🇧

    Motivated by the absence of signals of new physics at the LHC, which seems to imply the presence of large mass hierarchies, we investigate the theoretical possibility that these could arise dynamically in new strongly-coupled gauge theories extending the standard model of particle physics. To this purpose, we study lattice data on non-Abelian gauge theories in the (near-)conformal regime---specifically, $\mathrm{SU}(2)$ with $N_{\mathrm{f}}=1$ and $2$ dynamical fermion flavours in the adjoint representation. We focus our attention on the ratio $R$ between the masses of the lightest spin-2 and spin-0 resonances, and draw comparisons with a simple toy model in the context of gauge/gravity dualities. For models in which large anomalous dimensions arise dynamically, we show indications that this mass ratio can be large, with $R>5$. Moreover, our results suggest that $R$ might be related to universal properties of the IR fixed point. Our findings provide an interesting step towards understanding large mass ratios in the non-perturbative regime of quantum field theories with (near) IR conformal behaviour.

    ↳ hep-lathep-phPoS(2017)·4 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.