WorldWideScience

Sample records for boson expansion formalism

  1. Double beta decay to the first $2^+$ state within a boson expansion formalism with a projected spherical single particle basis

    CERN Document Server

    Raduta, A A

    2007-01-01

    The Gamow-Teller transition operator is written as a polynomial in the dipole proton-neutron and quadrupole charge conserving QRPA boson operators, using the prescription of the boson expansion technique of Belyaev-Zelevinski type. Then, the $2\

  2. Double beta decay to the first 2+ state within a boson expansion formalism with a projected spherical single particle basis

    International Nuclear Information System (INIS)

    The Gamow-Teller transition operator is written as a polynomial in the dipole proton-neutron and quadrupole charge conserving QRPA boson operators, using the prescription of the boson expansion technique of Belyaev-Zelevinski type. Then, the 2νββ process ending on the first 2+ state in the daughter nucleus is allowed via one, two and three boson states describing the odd-odd intermediate nucleus. The approach uses a single particle basis which is obtained by projecting out the good angular momentum from an orthogonal set of deformed functions. The bases for mother and daughter nuclei have different deformations. The GT transition amplitude as well as the half lives was calculated for eleven transitions. Results are compared with the available data as well as with some predictions obtained with other methods

  3. Loop expansion and the bosonic representation of loop quantum gravity

    CERN Document Server

    Bianchi, Eugenio; Hackl, Lucas; Yokomizo, Nelson

    2016-01-01

    We introduce a new loop expansion that provides a resolution of the identity in the Hilbert space of loop quantum gravity on a fixed graph. We work in the bosonic representation obtained by the canonical quantization of the spinorial formalism. The resolution of the identity gives a tool for implementing the projection of states in the full bosonic representation onto the space of solutions to the Gauss and area matching constraints of loop quantum gravity. This procedure is particularly efficient in the semiclassical regime, leading to explicit expressions for the loop expansions of coherent, heat kernel and squeezed states.

  4. Partial bosonization: The formalism of Cheshire Cat bag models

    International Nuclear Information System (INIS)

    By bosonizing fermionic theories on only a part of space-time, one obtains idealized bag models where the physics is independent of the bag radius. Such ''Cheshire Cat Models (CCM's)'' were introduced in an earlier paper, where it was suggested that realistic bag models are in fact approximate CCM's. The present paper further explores Abelian CCM's in 1+1 dimensions. First, the boundary action for CCM's is derived in the Lagrangian formalism by demanding invariance under parity and chiral rotations. Next, a quantum reinterpretation of the classical Lagrangian bag boundary conditions is used to obtain the bosonic representation of fermions as soliton operators. Last, these soliton operators are used to construct CCM's in the Hamiltonian framework. The Cheshire Cat criterion - independence of the energy spectrum on the bag radius - is presented as the commuting of the energy and momentum operators for the model. (orig.)

  5. Did the Higgs boson drive the universe's expansion?

    CERN Multimedia

    2008-01-01

    The Higgs boson has been moonlighting. Not content with its day job of giving other particles their mass, it may also have driven the expansion of the early universe, given a little tinkering, according to two separate studies. Soon after the big bang the early universe is believed to have undergone a period of rapid expansion, known as inflation.

  6. 1/N expansion in the interacting boson model. II. The neutron-proton degree of freedon

    International Nuclear Information System (INIS)

    The 1/N expansion method is used to study the neutron-proton degree of freedom in a general boson model. Employing a standard IBM-2 hamiltonian, analytic expressions for energies and electromagnetic transition rates are derived both for the symmetric and mixed-symmetry states. A formalism for F-spin analysis is developed. Effects of the g-boson and F-spin breaking in various quantities are discussed. The method is not restricted to dynamic symmetries and allows for explicit breaking of the F-spin symmetry. Thus, the formulae derived here should be useful for systematic analysis of deformed nuclei in realistic situations. 42 refs., 13 figs

  7. Parameterized type expansion in the feature structure formalism TDL

    OpenAIRE

    Schäfer, Ulrich

    1995-01-01

    Over the last few years, unification-based grammar formalisms have become the predominant paradigm in natural language processing systems because of their monotonicity, declarativeness, and reversibility. From the viewpoint of computer science, typed feature structures can be seen as data structures that allow representation of linguistic knowledge in a uniform fashion. Type expansion is an operation that makes the constraints on a typed feature structure explicit and determines their satisfi...

  8. Formal GNS Construction and WKB Expansion in Deformation Quantization

    CERN Document Server

    Bordemann, Martin

    1996-01-01

    In this contribution we review the formal GNS construction developped in a previous preprint (q-alg/9607019), and formulate the usual WKB-expansion in flat 2n-dimensional phase space in terms of a GNS construction with a positive linear functional with support on a projectable Lagrangean submanifold defined as a graph of an exact one form dS. The main trick is a suitable form of the star-exponential of S.

  9. Heat kernel expansion in the background field formalism

    CERN Document Server

    Barvinsky, Andrei

    2015-01-01

    Heat kernel expansion and background field formalism represent the combination of two calculational methods within the functional approach to quantum field theory. This approach implies construction of generating functionals for matrix elements and expectation values of physical observables. These are functionals of arbitrary external sources or the mean field of a generic configuration -- the background field. Exact calculation of quantum effects on a generic background is impossible. However, a special integral (proper time) representation for the Green's function of the wave operator -- the propagator of the theory -- and its expansion in the ultraviolet and infrared limits of respectively short and late proper time parameter allow one to construct approximations which are valid on generic background fields. Current progress of quantum field theory, its renormalization properties, model building in unification of fundamental physical interactions and QFT applications in high energy physics, gravitation and...

  10. Spherical waves for Dirac--K\\"{a}hler and Dirac particles, formal relations between boson and fermion solutions

    CERN Document Server

    Red'kov, V M

    2011-01-01

    Tetrad based equation for Dirac-K\\"{a}hler particle is solved in spherical coordinates in the flat Minkocski space-time. Spherical solutions of boson type (J =0,1,2,...) are constructed. After performing a special transformation over spherical boson solutions of the Dirac-K\\"{a}hler equation, 4 \\times 4-matrices U(x) \\Longrightarrow V(x), simple linear expansions of the four rows of new representativeof the Dirac--K\\"{a}hler field V(x) in terms of spherical fermion solutions \\Psi_{i}(x) of the four ordinary Dirac equations have been derived. However, this fact cannot be interpreted as the possibility not to distinguish between the Dirac-K\\"{a}hler field and the system four Dirac fermions. The main formal argument is that the special transformation (I \\otimes S(x)) involved does not belong to the group of tetrad local gauge transformation for Dirac-K\\"{a}hler field, 2-rank bispinor under the Lorentz group. Therefore, the linear expansions between boson and fermion functions are not gauge invariant under the gr...

  11. Contributions to the Study of Thermal States of the Bosonic String in the TFD Formalism

    CERN Document Server

    Graça, E L

    2007-01-01

    We determine the local entropy of the free energy of the quantized open bosonic string in Minkowski spacetime with the most general boundary conditions. We formulate a finite temperature theory of the thermal closed string excitations in anti-de Sitter spacetime within the TFD approach. We write down the thermal states and obtain the entropy and the free energy in the first order expansion of the semiclassical quantization in the center of mass reference frame.

  12. Functional integrals and 1/h expansion in the boson-fermion model

    Science.gov (United States)

    Yan, Jun

    2016-06-01

    The effective action of boson-fermion model is derived by means of the functional integrals method and Popov-Faddeev canonical transformations. The energy gap equation and excitation spectrum equation are obtained from first order and second order perturbation expansions of functional determinant. In the long wave approximation, some analytical expressions of excitation spectrum are calculated by using the 1/h expansion technique, the results showed that analytical calculation is in good agreement with the numerical calculation. Moreover, the Nambu sum rules of Higgs bosons are analyzed and discussed.

  13. Economic expansion and increase in labout market formality: a poaching approach

    Directory of Open Access Journals (Sweden)

    Carlos Henrique L. Corseuil

    2012-06-01

    Full Text Available This paper investigates the relationship between economic expansion and the degree of formalization for the Brazilian labour market in the recent period. We present a theoretical framework that attempts to explain this relationship through the dynamics of firms hiring strategies. The main predictions are: the share of formal employment rises as the unemployment rate falls, and that the formal-informal wage gap increases, at least at the beginning of the economic expansion. In the empirical part, we use longitudinal microdata from a Brazilian household survey to check whether these two predictions are confirmed. To a large extent our results corroborate both predictions.

  14. Free expansion of fermionic dark solitons in a boson-fermion mixture

    International Nuclear Information System (INIS)

    We use a time-dependent dynamical mean-field-hydrodynamic model to study the formation of fermionic dark solitons in a trapped degenerate Fermi gas mixed with a Bose-Einstein condensate in a harmonic as well as a periodic optical-lattice potential. The dark soliton with a 'notch' in the probability density with a zero at the minimum is simulated numerically as a nonlinear continuation of the first vibrational excitation of the linear mean-field-hydrodynamic equations, as suggested recently for pure bosons. We study the free expansion of these dark solitons as well as the consequent increase in the size of their central notch and discuss the possibility of experimental observation of the notch after free expansion

  15. Bosonization

    CERN Document Server

    1994-01-01

    Bosonization is a useful technique for studying systems of interacting fermions in low dimensions. It has applications in both particle and condensed matter physics.This book contains reprints of papers on the method as used in these fields. The papers range from the classic work of Tomonaga in the 1950's on one-dimensional electron gases, through the discovery of fermionic solitons in the 1970's, to integrable systems and bosonization on Riemann surfaces. A four-chapter pedagogical introduction by the editor should make the book accessible to graduate students and experienced researchers alik

  16. Massive two-column bosonic fields in the frame-like formalism

    CERN Document Server

    Zinoviev, Yu M

    2016-01-01

    In this paper we develop the frame-like gauge invariant formulation for the massive two-column bosonic fields in (anti) de Sitter space-times. We begin with the partially massless cases in AdS and dS and then we combine these results into the general massive theory. Separate section is devoted to the special case where both columns have equal number of indices.

  17. Simple formalism for efficient derivatives and multi-determinant expansions in quantum Monte Carlo

    Science.gov (United States)

    Filippi, Claudia; Assaraf, Roland; Moroni, Saverio

    2016-05-01

    We present a simple and general formalism to compute efficiently the derivatives of a multi-determinant Jastrow-Slater wave function, the local energy, the interatomic forces, and similar quantities needed in quantum Monte Carlo. Through a straightforward manipulation of matrices evaluated on the occupied and virtual orbitals, we obtain an efficiency equivalent to algorithmic differentiation in the computation of the interatomic forces and the optimization of the orbital parameters. Furthermore, for a large multi-determinant expansion, the significant computational gain afforded by a recently introduced table method is here extended to the local value of any one-body operator and to its derivatives, in both all-electron and pseudopotential calculations.

  18. Dressed Bosons and Effective Temperature — a Formalism for Helium II

    Science.gov (United States)

    Maćkowiak, Jan; Borycki, Dawid

    2012-08-01

    The thermodynamics of a free Bose gas with effective temperature scale ˜ {T} and hard-sphere Bose gas with the ˜ {T} scale are studied. ˜ {T} arises as the temperature experienced by a single particle in a quantum gas with 2-body harmonic oscillator interaction Vosc, which at low temperatures is expected to simulate, almost correctly, the attractive part of the interatomic potential VHe between 4He atoms. The repulsive part of VHe is simulated by a hard-sphere (HS) potential. The thermodynamics of this system of HS bosons, with the ˜ {T} temperature scale (HSET), and particle mass and density equal to those of 4He, is investigated, first, by the Bogoliubov-Huang method and next by an improved version of this method, which describes He II in terms of dressed bosons and takes approximate account of those terms of the 2-body repulsion which are linear in the zero-momentum Bose operators a0, a*0 (originally rejected by Bogoliubov). Theoretical heat capacity CV(T) exhibits good agreement, below 1.9 K, with the experimental heat capacity graph observed in 4He at saturated vapour pressure. The phase transition to the He II phase, occurs in the HSET at Tλ = 2.17 K, and is accompanied, in the modified HSET version, by a singularity of CV(T). The fraction of atoms in the momentum condensate at 0 K equals 8.86% and agrees with other theoretical estimates for He II. The fraction of normal fluid falls to 8.37% at 0 K which exceeds the value 0% found in He II.

  19. The $\\{\\beta\\}$-expansion formalism in perturbative QCD and its extension

    CERN Document Server

    Kataev, A L

    2016-01-01

    We discuss the $\\{ \\beta \\}$-expansion for renormalization group invariant quantities tracing this expansion to the different contractions of the corresponding incomplete BPHZ $R$-operation. All of the coupling renormalizations, which follow from these contractions, should be taken into account for the $\\{ \\beta \\}$-expansion. We illustrate this feature considering the nonsinglet Adler function $D^\\text{NS}$ in the third order of perturbation. We propose a generalization of the $\\{ \\beta \\}$-expansion for the renormalization group covariant quantities -- the $\\{ \\beta,\\gamma \\}$-expansion.

  20. Interference of composite bosons

    OpenAIRE

    Brougham, Thomas; Barnett, Stephen M.; Jex, Igor

    2010-01-01

    We investigate multi-boson interference. A Hamiltonian is presented that treats pairs of bosons as a single composite boson. This Hamiltonian allows two pairs of bosons to interact as if they were two single composite bosons. We show that this leads to the composite bosons exhibiting novel interference effects such as Hong-Ou-Mandel interference. We then investigate generalizations of the formalism to the case of interference between two general composite bosons. Finally, we show how one can ...

  1. Bosonization of the generalized SU(3) Nambu-Jona-Lasinio model in the 1/N expansion

    International Nuclear Information System (INIS)

    The present work consists in a 1/N expansion of extended version of the SU(3) Nambu-Jona-Lasinio model in the context of the Functional Integral. The gap equations, meson propagators, triangle diagram, etc, appear quite naturally as different orders in the expansion. The new features of this approach is the inclusion of high order corrections in the 1/N leading orders, which have never included in the previous one. The method also allows for the construction of a chiral Lagrangian of interacting mesons based on the SU(3) NJL model, here obtained for the first time. (author)

  2. Gauge-Invariant Formalism with Dirac-mode Expansion for Confinement and Chiral Symmetry Breaking

    CERN Document Server

    Gongyo, Shinya; Suganuma, Hideo

    2012-01-01

    We develop a manifestly gauge-covariant expansion of the QCD operator such as the Wilson loop, using the eigen-mode of the QCD Dirac operator $\\Slash D=\\gamma^\\mu D^\\mu$. With this method, we perform a direct analysis of the correlation between confinement and chiral symmetry breaking in lattice QCD Monte Carlo calculation on $6^4$ at $\\beta$=5.6. As a remarkable fact, the confinement force is almost unchanged even after removing the low-lying Dirac modes, which are responsible to chiral symmetry breaking. This indicates that one-to-one correspondence does not hold for between confinement and chiral symmetry breaking in QCD. In this analysis, we carefully amputate only the "essence of chiral symmetry breaking" by cutting off the low-lying Dirac modes, and can artificially realize the "confined but chiral restored situation" in QCD.

  3. Lattice Boltzmann method for bosons and fermions and the fourth order Hermite polynomial expansion

    CERN Document Server

    Coelho, Rodrigo C V; Doria, M M; Pereira, R M; Aibe, Valter Yoshihiko

    2013-01-01

    The Boltzmann equation with the Bhatnagar-Gross-Krook collision operator is considered for the Bose-Einstein and Fermi-Dirac equilibrium distribution functions. We show that the expansion of the microscopic velocity in terms of Hermite polynomials must be carried until the fourth order to correctly describe the energy equation. The viscosity and thermal coefficients, previously obtained by J.Y. Yang et al through the Uehling-Uhlenbeck approach, are also derived here. Thus the construction of a lattice Boltzmann method for the quantum fluid is possible provided that the Bose-Einstein and Fermi-Dirac equilibrium distribution functions are expanded until fourth order in the Hermite polynomials.

  4. Sudden expansion and domain-wall melting of strongly interacting bosons in two-dimensional optical lattices and on multileg ladders

    Science.gov (United States)

    Hauschild, Johannes; Pollmann, Frank; Heidrich-Meisner, Fabian

    2015-11-01

    We numerically investigate the expansion of clouds of hard-core bosons in the two-dimensional square lattice using a matrix-product-state-based method. This nonequilibrium setup is induced by quenching the trapping potential to zero and our work is specifically motivated by a recent experiment with interacting bosons in an optical lattice [Ronzheimer et al., Phys. Rev. Lett. 110, 205301 (2013), 10.1103/PhysRevLett.110.205301]. As the anisotropy of the amplitudes Jx and Jy for hopping in different spatial directions is varied from the one- to the two-dimensional case, we observe a crossover from a fast ballistic expansion in the one-dimensional limit Jx≫Jy to much slower dynamics in the isotropic two-dimensional limit Jx=Jy . We further study the dynamics on multileg ladders and long cylinders. For these geometries we compare the expansion of a cloud to the melting of a domain wall, which helps us to identify several different regimes of the expansion as a function of time. By studying the dependence of expansion velocities on both the anisotropy Jy/Jx and the number of legs, we observe that the expansion on two-leg ladders, while similar to the two-dimensional case, is slower than on wider ladders. We provide a qualitative explanation for this observation based on an analysis of the rung spectrum.

  5. The Higgs boson and the quark top in the formalism of dispersion relations and the standard model

    International Nuclear Information System (INIS)

    The mechanism of spontaneous symmetry breaking responsible for the generation of masses for both the bosons and the fermions of the Standard Model remains a mystery, especially that the Higgs has still not been discovered. In this thesis I concentrate on the study of the scalar sector of the Standard Model where the Higgs with the other Goldstone Bosons reside. This sector can best be probed through the massive vector bosons and the top quark. The former, for their privileged coupling to the Higgs and because their longitudinal mode represents the Goldstone Bosons, and the top, because of its very strong Yukawa coupling, are very sensitive to the mechanism of symmetry breaking. I first focus on a situation where the Higgs is light and study the processes W-W+ → tt-bar and ZZ → tt-bar. In order to unambiguously reveal a sign of New Physics, the Standard Model needs to be predicted precisely. In a first step I therefore study the electroweak and QCD one loop corrections for these processes. This requires a renormalisation of the electroweak gauge and top sectors and mastering some one-loop techniques. I then concentrate on extracting the purely electroweak contributions to the above processes after setting up an analytical formula for the universal photonic contribution. The New Physics affecting the top and W system is parameterized with the help of effective operators describing symmetry breaking. The effect of these operators is carefully compared to the effect of the one-loop radiative corrections before setting a limit on the parameters of these New Physics operators. To give more realistic results the WW and ZZ cross sections are turned into e+e- and pp cross sections by using a structure function approach. This allows an application to the phenomenology at future colliders (LHC:Large Hadron Collider and ILC: International Linear Collider). A second aspect of the work presented here concerns the situation where the Higgs is heavy. For a heavy Higgs the

  6. Thermal expansion characteristics of a titanium modified austenitic stainless steel: measurement by high-temperature X-ray diffraction and modelling using Grueneisen formalism

    Energy Technology Data Exchange (ETDEWEB)

    Jose, R.; Raju, S. E-mail: sraju@igcar.ernet.in; Divakar, R.; Mohandas, E.; Panneerselvam, G.; Antony, M.P.; Sivasubramanian, K

    2003-04-01

    The thermal expansion of a titanium modified, swelling resistant austenitic stainless steel designated as D9 is studied by measuring the lattice parameter as a function of temperature in the range 300-1300 K by high-temperature X-ray diffraction technique. The thermal expansion data thus obtained is in reasonable agreement with the typical thermal expansion values reported for similar nuclear grade austenitic stainless steels. However, at temperatures exceeding 900 K, the measured thermal expansivity exhibits a pronounced non-linear increase due partly to the precipitation of complex carbide and intermetallic phases. The high-temperature thermal expansion data obtained in the present study are augmented by modelling the low-temperature thermal expansion behaviour by Grueneisen formalism.

  7. Thermal expansion characteristics of a titanium modified austenitic stainless steel: measurement by high-temperature X-ray diffraction and modelling using Grueneisen formalism

    International Nuclear Information System (INIS)

    The thermal expansion of a titanium modified, swelling resistant austenitic stainless steel designated as D9 is studied by measuring the lattice parameter as a function of temperature in the range 300-1300 K by high-temperature X-ray diffraction technique. The thermal expansion data thus obtained is in reasonable agreement with the typical thermal expansion values reported for similar nuclear grade austenitic stainless steels. However, at temperatures exceeding 900 K, the measured thermal expansivity exhibits a pronounced non-linear increase due partly to the precipitation of complex carbide and intermetallic phases. The high-temperature thermal expansion data obtained in the present study are augmented by modelling the low-temperature thermal expansion behaviour by Grueneisen formalism

  8. Description of deformed nuclei in the sdg boson model

    OpenAIRE

    S. C. Li; Kuyucak, S.

    1996-01-01

    We present a study of deformed nuclei in the framework of the sdg interacting boson model utilizing both numerical diagonalization and analytical $1/N$ expansion techniques. The focus is on description of high-spin states which have recently become computationally accessible through the use of computer algebra in the $1/N$ expansion formalism. A systematic study is made of high-spin states in rare-earth and actinide nuclei.

  9. Description of deformed nuclei in the sdg boson model

    CERN Document Server

    Li, S C

    1996-01-01

    We present a study of deformed nuclei in the framework of the sdg interacting boson model utilizing both numerical diagonalization and analytical 1/N expansion techniques. The focus is on description of high-spin states which have recently become computationally accessible through the use of computer algebra in the 1/N expansion formalism. A systematic study is made of high-spin states in rare-earth and actinide nuclei.

  10. High-spin states in boson models with applications to actinide nuclei

    CERN Document Server

    Kuyucak, S

    1995-01-01

    We use the 1/N expansion formalism in a systematic study of high-spin states in the sd and sdg boson models with emphasis on spin dependence of moment of inertia and E2 transitions. The results are applied to the high-spin states in the actinide nuclei ^{232}Th, ^{234-238}U, where the need for g bosons is especially acute but until now, no realistic calculation existed. We find that the d-boson energy plays a crucial role in description of the high-spin data.

  11. Higgs boson gluon-fusion production beyond threshold in N 3 LO QCD

    OpenAIRE

    Anastasiou, Charalampos(Institute for Theoretical Physics, ETH Zürich, Zürich, 8093, Switzerland); Duhr, Claude; Dulat, Falko; Furlan, Elisabetta; Gehrmann, Thomas; Herzog, Franz; Mistlberger, Bernhard

    2015-01-01

    In this article, we compute the gluon fusion Higgs boson cross-section at N 3 LO through the second term in the threshold expansion. This calculation constitutes a major milestone towards the full N 3 LO cross section. Our result has the best formal accuracy in the threshold expansion currently available, and includes contributions from collinear regions besides subleading corrections from soft and hard regions, as well as certain logarithmically enhanced contributions for general kinematics....

  12. Deformation quantization of bosonic strings

    International Nuclear Information System (INIS)

    Deformation quantization of bosonic strings is considered. We show that the light-cone gauge is the most convenient classical description to perform the quantization of bosonic strings in the deformation quantization formalism. Similar to the field theory case, the oscillator variables greatly facilitates the analysis. The mass spectrum, propagators and the Virasoro algebra are finally described within this deformation quantization scheme. (author)

  13. An introduction to boson-sampling

    OpenAIRE

    Gard, Bryan T; Motes, Keith R.; Olson, Jonathan P.; Rohde, Peter P.; Dowling, Jonathan P.

    2014-01-01

    Boson-sampling is a simplified model for quantum computing that may hold the key to implementing the first ever post-classical quantum computer. Boson-sampling is a non-universal quantum computer that is significantly more straightforward to build than any universal quantum computer proposed so far. We begin this chapter by motivating boson-sampling and discussing the history of linear optics quantum computing. We then summarize the boson-sampling formalism, discuss what a sampling problem is...

  14. Fermion-fermion and boson-boson amplitudes: surprising similarities

    CERN Document Server

    Dvoeglazov, Valeri V

    2007-01-01

    Amplitudes for fermion-fermion, boson-boson and fermion-boson interactions are calculated in the second order of perturbation theory in the Lobachevsky space. An essential ingredient of the model is the Weinberg's 2(2j+1)-component formalism for describing a particle of spin j. The boson-boson amplitude is then compared with the two-fermion amplitude obtained long ago by Skachkov on the basis of the Hamiltonian formulation of quantum field theory on the mass hyperboloid, p_0^2 - p^2=M^2, proposed by Kadyshevsky. The parametrization of the amplitudes by means of the momentum transfer in the Lobachevsky space leads to same spin structures in the expressions of T-matrices for the fermion case and the boson case. However, certain differences are found. Possible physical applications are discussed.

  15. Is geometry bosonic or fermionic?

    CERN Document Server

    Hughes, Taylor L

    2011-01-01

    It is generally assumed that the gravitational field is bosonic. Here we show that a simple propagating torsional theory can give rise to localized geometric structures that can consistently be quantized as fermions under exchange. To demonstrate this, we show that the model can be formally mapped onto the Skyrme model of baryons, and we use well-known results from Skyrme theory. This begs the question: {\\it Is geometry bosonic or fermionic (or both)?}

  16. Resummation of High Order Corrections in Higgs Boson Plus Jet Production at the LHC

    CERN Document Server

    Sun, Peng; Yuan, C -P; Yuan, Feng

    2016-01-01

    We study the effect of multiple parton radiation to Higgs boson plus jet production at the LHC, by applying the transverse momentum dependent (TMD) factorization formalism to resum large logarithmic contributions to all orders in the expansion of the strong interaction coupling. We show that the appropriate resummation scale should be the jet transverse momentum, rather than the partonic center of mass energy which has been normally used in the TMD resummation formalism. Furthermore, the transverse momentum distribution of the Higgs boson, particularly near the lower cut-off applied on the jet transverse momentum, can only be reliably predicted by the resummation calculation which is free of the so-called Sudakov-shoulder singularity problem, present in fixed-order calculations.

  17. Probing anomalous gauge boson couplings at LEP

    International Nuclear Information System (INIS)

    We bound anomalous gauge boson couplings using LEP data for the Z → bar ∫∫ partial widths. We use an effective field theory formalism to compute the one-loop corrections resulting from non-standard model three and four gauge boson vertices. We find that measurements at LEP constrain the three gauge boson couplings at a level comparable to that obtainable at LEPII

  18. Quakers, coercion and pre-modern growth: why friends’ formal institutions for contract enforcement did not matter for early Atlantic trade expansion

    OpenAIRE

    Sahle, Esther

    2014-01-01

    During the late seventeenth century the Atlantic trade experienced unprecedented growth. The New Institutional Economists attribute this to the emergence of new institutions for property rights enforcement. During this period, Quakers emerged as the region’s most prominent trading community. This paper constitutes the first study of the London Quaker community. In contrast to the literature, claiming that they enjoyed a competitive advantage due to their church’s formal institutions for co...

  19. Boson representation of the asymmetric rotator

    International Nuclear Information System (INIS)

    The yrast states, as well as the wobbling frequency are analyzed using alternatively the Holstein-Primakoff and Dyson boson expansions. Both the prolate and oblate shapes are treated using Oz as quantization axis. (author)

  20. A general approach to bosonization

    Indian Academy of Sciences (India)

    Girish S Setulur; V Meera

    2007-10-01

    We summarize recent developments in the field of higher dimensional bosonization made by Setlur and collaborators and propose a general formula for the field operator in terms of currents and densities in one dimension using a new ingredient known as a `singular complex number'. Using this formalism, we compute the Green function of the homogeneous electron gas in one spatial dimension with short-range interaction leading to the Luttinger liquid and also with long-range interactions that lead to a Wigner crystal whose momentum distribution computed recently exhibits essential singularities. We generalize the formalism to finite temperature by combining with the author's hydrodynamic approach. The one-particle Green function of this system with essential singularities cannot be easily computed using the traditional approach to bosonization which involves the introduction of momentum cutoffs, hence the more general approach of the present formalism is proposed as a suitable alternative.

  1. An Introduction to Boson-Sampling

    Science.gov (United States)

    Gard, Bryan T.; Motes, Keith R.; Olson, Jonathan P.; Rohde, Peter P.; Dowling, Jonathan P.

    2015-06-01

    Boson-sampling is a simplified model for quantum computing that may hold the key to implementing the first ever post-classical quantum computer. Boson-sampling is a non-universal quantum computer that is significantly more straightforward to build than any universal quantum computer proposed so far. We begin this chapter by motivating boson-sampling and discussing the history of linear optics quantum computing. We then summarize the boson-sampling formalism, discuss what a sampling problem is, explain why boson-sampling is easier than linear optics quantum computing, and discuss the Extended Church-Turing thesis. Next, sampling with other classes of quantum optical states is analyzed. Finally, we discuss the feasibility of building a boson-sampling device using existing technology.

  2. Introduction to bosonic string theory

    International Nuclear Information System (INIS)

    This is an introductory set of five lectures on bosonic string theory. The first one deals with the classical theory of bosonic strings. The second and third lectures cover quantization. Three basic quantization methods are sketched: the old covariant formalism, the light-cone gauge quantization, where the spectrum is derived and the Polyakov path integral formalism and in particular the partition function at one loop. Finally, the last lecture covers interactions, low energy effective action, the general idea of compactification and in particular toroidal compactification. The notes are based on books by Green, Schwarz and Witten, Polchinski, Lust and Theissen and Kaku and review papers by D'Hocker and Phong and O. Alvarez. (author)

  3. Two-boson composites

    DEFF Research Database (Denmark)

    Tichy, Malte C.; Bouvrier, P. Alexander; Mølmer, Klaus

    2013-01-01

    Composite bosons made of two bosonic constituents exhibit deviations from ideal bosonic behavior due to their substructure. This deviation is reflected by the normalization ratio of the quantum state of N composites. We find a set of saturable, efficiently evaluable bounds for this indicator, which...... quantifies the bosonic behavior of composites via the entanglement of their constituents. We predict an abrupt transition between ordinary and exaggerated bosonic behavior in a condensate of two-boson composites....

  4. Introduction to bosonization

    International Nuclear Information System (INIS)

    This is a pedagogical introduction to the general technique of bosonization of one-dimensional systems starting from scratch and assuming very little besides basic quantum mechanics and second quantization. The formalism is developed in a self-contained fashion and applied to the spinless and spin-1/2 Luttinger models, working out both single and two particle correlation functions. The implications of these results for the specific cases of the (anisotropic) Heisenberg and the Hubbard models are discussed. Although everything in these notes can be found in the published literature, detailed and explicit calculations of most of the results are given, which may prove useful to beginning graduate students or researchers in this area. (author)

  5. Bosonization and quantum hydrodynamics

    Indian Academy of Sciences (India)

    Girish S Setlur

    2006-03-01

    It is shown that it is possible to bosonize fermions in any number of dimensions using the hydrodynamic variables, namely the velocity potential and density. The slow part of the Fermi field is defined irrespective of dimensionality and the commutators of this field with currents and densities are exponentiated using the velocity potential as conjugate to the density. An action in terms of these canonical bosonic variables is proposed that reproduces the correct current and density correlations. This formalism in one dimension is shown to be equivalent to the Tomonaga-Luttinger approach as it leads to the same propagator and exponents. We compute the one-particle properties of a spinless homogeneous Fermi system in two spatial dimensions with long-range gauge interactions and highlight the metal-insulator transition in the system. A general formula for the generating function of density correlations is derived that is valid beyond the random phase approximation. Finally, we write down a formula for the annihilation operator in momentum space directly in terms of number conserving products of Fermi fields.

  6. Aharonov--Bohm problem for vector bosons

    CERN Document Server

    Castro, Luis B

    2015-01-01

    The Aharonov--Bohm (AB) problem for vector bosons by the Duffin--Kemmer--Petiau (DKP) formalism is analyzed. The relevant eigenvalue equation coming from the DKP formalism reveals an equivalence to the spin--$1/2$ AB problem. By using the self--adjoint extension approach, we examine the bound state scenario. The energy spectra are explicitly computed as well as their dependencies on the magnetic flux parameter and also the conditions for the occurrence of bound states.

  7. Boson condensation in topologically ordered quantum liquids

    Science.gov (United States)

    Neupert, Titus; He, Huan; von Keyserlingk, Curt; Sierra, Germán; Bernevig, B. Andrei

    2016-03-01

    Boson condensation in topological quantum field theories (TQFT) has been previously investigated through the formalism of Frobenius algebras and the use of vertex lifting coefficients. While general, this formalism is physically opaque and computationally arduous: analyses of TQFT condensation are practically performed on a case by case basis and for very simple theories only, mostly not using the Frobenius algebra formalism. In this paper, we provide a way of treating boson condensation that is computationally efficient. With a minimal set of physical assumptions, such as commutativity of lifting and the definition of confined particles, we can prove a number of theorems linking Boson condensation in TQFT with chiral algebra extensions, and with the factorization of completely positive matrices over Z+. We present numerically efficient ways of obtaining a condensed theory fusion algebra and S matrices; and we then use our formalism to prove several theorems for the S and T matrices of simple current condensation and of theories which upon condensation result in a low number of confined particles. We also show that our formalism easily reproduces results existent in the mathematical literature such as the noncondensability of five and ten layers of the Fibonacci TQFT.

  8. Formal Phonology

    Directory of Open Access Journals (Sweden)

    Dave Odden

    2013-02-01

    Full Text Available Normal 0 false false false EN-US JA X-NONE Two problematic trends have dominated modern phonological theorizing: over-reliance on machinery of Universal Grammar, and reification of functional properties in grammar. The former trend leads to arbitrary postulation of grammatical principles because UG “has no cost”, which leads to a welter of contradictory and unresolvable claims. The latter trend amounts to rejection of phonology and indeed grammatical computation, as a legitimate independent area of scientific investigation. This paper outlines Formal Phonology, which is a metatheoretical approach rooted in an inductive epistemology, committed to seriously engaging the fundamental logic of the discipline, one which demands justification of claims and an integrated consideration of what is known about phonological grammars, eschewing ad libitum conjectures and isolated positing of novel claims without evaluating how the claim interacts with other aspects of phonology. Debate over the proper mechanism for apparent segment-transparency in harmony, or the binary vs. privative nature of features, is ultimately doomed if we do not have a clear awareness of what a “grammar” and a “phonology” are. Misconstruing the nature of a phonology as being a model of observed behavior negatively affects theoretical choices, leads to confusion over what could motivate a claim about the nature of grammar, and in general, a lack of developed epistemological foundation leads to confusion over how to approach theory-construction.

  9. Exactly solvable models of proton and neutron interacting bosons

    International Nuclear Information System (INIS)

    We describe a class of exactly-solvable models of interacting bosons based on the algebra SO(3, 2). Each copy of the algebra represents a system of neutron and proton bosons in a given bosonic level interacting via a pairing interaction. The model that includes s and d bosons is a specific realization of the IBM2, restricted to the transition regime between vibrational and γ-soft nuclei. By including additional copies of the algebra, we can generate proton-neutron boson models involving other boson degrees of freedom, while still maintaining exact solvability. In each of these models, we can study not only the states of maximal symmetry, but also those of mixed symmetry, albeit still in the vibrational to γ-soft transition regime. Furthermore, in each of these models we can study some features of F-spin symmetry breaking. We report systematic calculations as a function of the pairing strength for models based on s,d, and g bosons and on s,d, and f bosons. The formalism of exactly-solvable models based on the SO(3, 2) algebra is not limited to systems of proton and neutron bosons, however, but can also be applied to other scenarios that involve two species of interacting bosons

  10. Worldline Formalism and Noncommutative Theories

    CERN Document Server

    Franchino-Viñas, Sebastián A

    2015-01-01

    The objective of this Ph.D. thesis is the implementation of the Worldline Formalism in the frame of Noncommutative Quantum Field Theories. The result is a master formula for the 1-loop effective action that is applied to a number of scalar models -- among them the Grosse-Wulkenhaar model. As a byproduct we find an expression for the small propertime expansion of general nonlocal operators' Heat Kernel. As an introduction, basic notions of spectral functions, Quantum Field Theories --path integrals and renormalization by means of spectral functions-- and the Worldline Formalism for commutative theories are given.

  11. The Higgs Boson.

    Science.gov (United States)

    Veltman, Martinus J. G.

    1986-01-01

    Reports recent findings related to the particle Higgs boson and examines its possible contribution to the standard mode of elementary processes. Critically explores the strengths and uncertainties of the Higgs boson and proposed Higgs field. (ML)

  12. Higgs boson : production and decays into bosons

    CERN Document Server

    Escalier, Marc; The ATLAS collaboration

    2016-01-01

    The results on the Higgs boson with decay channels into bosons from the ATLAS and CMS experiments at LHC Run 1 and early Run 2 are reviewed in the context of the Standard Model. : observation of a signal, measurement of mass, width, spin, cross-sections, search for decay channels and production modes, Higgs couplings to various particles.

  13. Scattering problem for four-boson system

    International Nuclear Information System (INIS)

    The s-wave phase shift of boson-triboson scattering has been obtained by solving the Faddeev-Osborn equation in the exact approach based on rigorous Faddeev theory. The Schmidt expansion theorem is used to express the 3+1- and 2+2-subamplitudes at energies in the continuous spectrum region as an infinite series of separable terms. Employing the pole term decomposition for these subamplitudes expressed in terms of the Schmidt expansion we can define, in conformity with the Faddeev residue prescription, respective four-nucleon amplitudes that describe elastic/rearrangement, partial breakup and full breakup scattering processes. Acquired simultaneous equations of these amplitudes take the form of multichannel two-particle Lippmann-Schwinger type, which we call Faddeev-Osborn equation. Assuming as an s-wave spin-independent, rank one separable potential of the Yamaguchi type for the two-particle interaction, are derived the Faddeev-Osborn equation for the boson-triboson elastic scattering. To treat singularities appeared in our equation, the numerical calculation is performed in the framework of the complex-valued analysis by introducing contour rotation method. The boson-triboson elastic scattering amplitude for L=0 state of a four-boson system is obtained numerically in the incident boson laboratory energy region of 0.01-24.0 Mev, including only 1=0 state for the 3+1-subamplitude. The results of the phase shift obtained from the amplitudes are plotted as dots in Fig. 1. (author)

  14. Microscopic approach to the interacting boson model

    International Nuclear Information System (INIS)

    A method is outlined for analyzing the interacting boson model microscopically in terms of S- and D-fermion pairs. We derive the number operator approximation (NOA) of Otsuka and Arima by considering functions that generate normalizations and matrix elements of states built of S-pairs. An extension of the formalism leads to a generalization of the NOA including both S and D. This approximation is suggested as a starting point for determining the collective SD subspace in a dynamical way. The simplified fermion problem that results from restriction of the hamiltonian to the SD subspace can be mapped onto a corresponding sd boson problem. Due to the finiteness of the spermion space, and the non-orthogonality of the collective SD basis, the boson hamiltonian obtained is non-hermitian. (orig.)

  15. Two-level interacting boson models beyond the mean field

    CERN Document Server

    Arias, J M; García-Ramos, J E; Vidal, J

    2007-01-01

    The phase diagram of two-level boson Hamiltonians, including the Interacting Boson Model (IBM), is studied beyond the standard mean field approximation using the Holstein-Primakoff mapping. The limitations of the usual intrinsic state (mean field) formalism concerning finite-size effects are pointed out. The analytic results are compared to numerics obtained from exact diagonalizations. Excitation energies and occupation numbers are studied in different model space regions (Casten triangle for IBM) and especially at the critical points.

  16. Resummation of Goldstone boson contributions to the MSSM effective potential

    Science.gov (United States)

    Kumar, Nilanjana; Martin, Stephen P.

    2016-07-01

    We discuss the resummation of the Goldstone boson contributions to the effective potential of the minimal supersymmetric Standard Model. This eliminates the formal problems of spurious imaginary parts and logarithmic singularities in the minimization conditions when the tree-level Goldstone boson squared masses are negative or approach zero. The numerical impact of the resummation is shown to be almost always very small. We also show how to write the two-loop minimization conditions so that Goldstone boson squared masses do not appear at all, and so that they can be solved without iteration.

  17. Resummation of Goldstone boson contributions to the MSSM effective potential

    CERN Document Server

    Kumar, Nilanjana

    2016-01-01

    We discuss the resummation of the Goldstone boson contributions to the effective potential of the Minimal Supersymmetric Standard Model (MSSM). This eliminates the formal problems of spurious imaginary parts and logarithmic singularities in the minimization conditions when the tree-level Goldstone boson squared masses are negative or approach zero. The numerical impact of the resummation is shown to be almost always very small. We also show how to write the two-loop minimization conditions so that Goldstone boson squared masses do not appear at all, and so that they can be solved without iteration.

  18. Noninertial effects on the quantum dynamics of scalar bosons

    International Nuclear Information System (INIS)

    The noninertial effect of rotating frames on the quantum dynamics of scalar bosons embedded in the background of a cosmic string is considered. In this work, scalar bosons are described by the Duffin-Kemmer-Petiau (DKP) formalism. Considering the DKP oscillator in this background the combined effects of a rotating frames and cosmic string on the equation of motion, energy spectrum, and DKP spinor are analyzed and discussed in detail. Additionally, the effect of rotating frames on the scalar bosons' localization is studied. (orig.)

  19. Noninertial effects on the quantum dynamics of scalar bosons

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Luis B. [Universidade Federal do Maranhao, Departamento de Fisica, Sao Luis, MA (Brazil)

    2016-02-15

    The noninertial effect of rotating frames on the quantum dynamics of scalar bosons embedded in the background of a cosmic string is considered. In this work, scalar bosons are described by the Duffin-Kemmer-Petiau (DKP) formalism. Considering the DKP oscillator in this background the combined effects of a rotating frames and cosmic string on the equation of motion, energy spectrum, and DKP spinor are analyzed and discussed in detail. Additionally, the effect of rotating frames on the scalar bosons' localization is studied. (orig.)

  20. The Conformal Window from the Worldline Formalism

    CERN Document Server

    Armoni, Adi

    2009-01-01

    We use the worldline formalism to derive a universal relation for the lower boundary of the conformal window in non-supersymmetric QCD-like theories. The derivation relies on the convergence of the expansion of the fermionic determinant in terms of Wilson loops. The expansion shares a similarity with the lattice strong coupling expansion and the genus expansion in string theory. Our result relates the lower boundary of the conformal window in theories with different representations and different gauge groups. Finally, we use SQCD to estimate the boundary of the conformal window in QCD-like theories and compare it with other approaches.

  1. Boson mappings for elementary excitations in fermion systems

    International Nuclear Information System (INIS)

    The boson mapping formalism is presented with a dual purpose in mind. It is first demonstrated to constitute a microscopic formalism leading to the introduction of collective variables into the many-fermion problem in an exact and consistent manner. Secondly it is shown to present ideal exploring ground with a view to the reconciliation of phenomenological collective nuclear models and microscopic considerations. Of the various existing possibilities for the construction of a boson mapping, we single out the finite, non-unitary Dyson-Maleev mapping, emphasising the convenience of its finiteness, especially in investigations concerning formal aspects of the boson mapping formalism. A contribution to the theory of Dyson-Maleev mappinigs for fermion operators is made by introducing the construction of a consistent mapping for single fermion operators which is free of limitations previously imposed on such a mapping. In various fermion models studies it is shown how the Dyson-Maleev mapping can be utilized to obtain equivalent boson models which, however, can be restricted to yield information about the collective subspace only. As far as phenomenological models are concerned, some new light from a microscopic viewpiont is shed on the assumption underlying the interacting boson model as well as on the calculational procedures usually adopted in this model. The most important observation concerns the assumed structure of the IBM hamiltonian where a non-hermitian form, rather than the existing hermitian form, is indicated

  2. Bosonic behavior of entangled fermions

    DEFF Research Database (Denmark)

    C. Tichy, Malte; Alexander Bouvrie, Peter; Mølmer, Klaus

    2012-01-01

    Two bound, entangled fermions form a composite boson, which can be treated as an elementary boson as long as the Pauli principle does not affect the behavior of many such composite bosons. The departure of ideal bosonic behavior is quantified by the normalization ratio of multi-composite-boson st......Two bound, entangled fermions form a composite boson, which can be treated as an elementary boson as long as the Pauli principle does not affect the behavior of many such composite bosons. The departure of ideal bosonic behavior is quantified by the normalization ratio of multi...

  3. The new bosonic mechanism

    OpenAIRE

    Taratuta, Rostislav

    2015-01-01

    The main purpose of this paper is to introduce the new bosonic mechanism and newtreatment of dark energy. The bosonic mechanism focuses on obtaining masses by gauge bosonswithout assuming the existence of Higgs boson. The hypothesis on dark energy as the energy ofa postulated dark field was made and a combined gravitational-dark field was introduced. This fieldis the key to a specified approach and allows addressing the fundamental starting points of the mechanism.i. Complex scalar field is i...

  4. Bosonic Cascade Laser

    OpenAIRE

    Liew, T. C. H.; Glazov, M. M.; Kavokin, K. V.; Shelykh, I. A.; Kaliteevski, M A; Kavokin, A.V.

    2012-01-01

    We propose a concept of a quantum cascade laser based on transitions of bosonic quasiparticles (excitons and exciton-polaritons) in a parabolic potential trap in a semiconductor microcavity. This laser would emit terahertz radiation due to bosonic stimulation of excitonic transitions. Dynamics of a bosonic cascade is strongly different from the dynamics of a conventional fermionic cascade laser. We show that populations of excitonic ladders are parity-dependent and quantized if the laser oper...

  5. Equivalence relations between interacting Kemmer-Duffin and Klein-Gordon spin 0 and 1 boson fields

    International Nuclear Information System (INIS)

    Two formalisms- the Kemmer-Duffin and Klein-Gordon ones - are considered parallely in the spin 0 and 1 cases. Using the S-matrix approach which bases on interaction Lagrangian the transitions between the formalisms are found. A more detailed study is made for one-boson and two-boson interactions. An equivalence between the formalisms inside certain quite natural preconditions is evident

  6. Path-Integral Bosonization of Massive Gauged Thirring Model

    CERN Document Server

    Bufalo, R

    2011-01-01

    In this work the bosonization of two-dimensional massive gauged Thirring model in the path-integral framework is presented. After completing the bosonization prescription, by the fermionic mass expansion, we perform an analysis of the strong coupling regime of the model through the transition amplitude, regarding the intention of extending the previous result about the isomorphisms, at quantum level, of the massless gauged Thirring model to the massive case.

  7. Application of the coherent state formalism to multiply excited states

    International Nuclear Information System (INIS)

    A general expression is obtained for the matrix element of an m-body operator between coherent states constructed from multiple orthogonal coherent boson species. This allows the coherent state formalism to be applied to states possessing an arbitrarily large number of intrinsic excitation quanta. For illustration, the formalism is applied to the two-dimensional vibron model (U(3) model), to calculate the energies of all excited states in the large-N limit

  8. Bosonization of the generalized SU(3) Nambu-Jona-Lasinio model in the 1/N expansion; Bosonizacao do modelo de Nambu-Jona-Lasinio SU(3) generalizado na expansao 1/N

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Francisco Antonio Pena

    1995-12-31

    The present work consists in a 1/N expansion of extended version of the SU(3) Nambu-Jona-Lasinio model in the context of the Functional Integral. The gap equations, meson propagators, triangle diagram, etc, appear quite naturally as different orders in the expansion. The new features of this approach is the inclusion of high order corrections in the 1/N leading orders, which have never included in the previous one. The method also allows for the construction of a chiral Lagrangian of interacting mesons based on the SU(3) NJL model, here obtained for the first time. (author) 32 refs., 11 figs., 5 tabs.

  9. Masses of Formal Philosophy

    DEFF Research Database (Denmark)

    Masses of Formal Philosophy is an outgrowth of Formal Philosophy. That book gathered the responses of some of the most prominent formal philosophers to five relatively open and broad questions initiating a discussion of metaphilosophical themes and problems surrounding the use of formal methods in...... philosophy. Including contributions from a wide range of philosophers, Masses of Formal Philosophy contains important new responses to the original five questions....

  10. Prehistory of the Higgs boson

    International Nuclear Information System (INIS)

    A Higgs boson is a particle whose existence is predicted in a class of quantum field theories in which a symmetry under a Lie group of transformations of the fields is spontaneously broken by an asymmetric vacuum state. It is a quantum of certain excitations of the order parameter. Such spontaneous symmetry breaking was first proposed as a feature of theories of elementary particles in 1960, but it has a much longer history in the contest of condensed matter theory: in ferromagnetism as early as 1928, in superfluidity and also in superconductivity. It was Nambu who in 1960 first proposed relativistic models inspired by BCS theory as a means of generating fermion masses in elementary particle physics but the hadronic models he proposed lacked the local gauge invariance of their prototype. The connection between spontaneous symmetry and Goldstone bosons in relativistic theories were formally proved in 1962 but the experimental evidence against the existence of such particles in the real world cast a doubt on the viability of Nambu's ideas. Between 1962 and 1964 a debate developed in the literature about whether the Goldstone theorem could be evaded. The resolution of this difficulty finally came in 1964, when Higgs realized that theories with a local gauge invariance fail to satisfy one of the axioms on which the 1962 proof of the Goldstone theorem depends. By the end of July 1964, Higgs had also written down the simplest field-theoretic model that is now known as the Higgs model. (A.C.)

  11. Where Is Higgs Boson?

    CERN Multimedia

    2008-01-01

    Quantum physicists think they know the answer. Probabilistic calculations reveal than the data provided by previous experiments has been miscalculated and that the Higgs boson has in fact been discovered. Weird! The Higgs boson is the only particle predicted by the Standard Model that hasn't been discovered yet.

  12. The Higgs boson

    CERN Document Server

    Pimenta, Jean Jûnio Mendes; Natti, Érica Regina Takano; Natti, Paulo Laerte

    2013-01-01

    The Higgs boson was predicted in 1964 by British physicist Peter Higgs. The Higgs is the key to explain the origin of the mass of other elementary particles of Nature. However, only with the coming into operation of the LHC, in 2008, there were technological conditions to search for the Higgs boson. Recently, a major international effort conducted at CERN, by means of ATLAS and CMS experiments, has enabled the observation of a new bosonic particle in the region of 125 GeVs. In this paper, by means of known mechanisms of symmetry breaking that occur in the BCS theory of superconductivity and in the theory of nuclear pairing, we discuss the Higgs mechanism in the Standard Model. Finally, we present the current state of research looking for the Higgs boson and the alternative theories and extensions of the Standard Model for the elementary particle physics. Keywords: Higgs boson, BCS theory, nuclear pairing, Higgs mechanism, Standard Model.

  13. Bosonic Partition Functions

    CERN Document Server

    Kellerstein, M; Verbaarschot, J J M

    2016-01-01

    The behavior of quenched Dirac spectra of two-dimensional lattice QCD is consistent with spontaneous chiral symmetry breaking which is forbidden according to the Coleman-Mermin-Wagner theorem. One possible resolution of this paradox is that, because of the bosonic determinant in the partially quenched partition function, the conditions of this theorem are violated allowing for spontaneous symmetry breaking in two dimensions or less. This goes back to work by Niedermaier and Seiler on nonamenable symmetries of the hyperbolic spin chain and earlier work by two of the auhtors on bosonic partition functions at nonzero chemical potential. In this talk we discuss chiral symmetry breaking for the bosonic partition function of QCD at nonzero isospin chemical potential and a bosonic random matrix theory at imaginary chemical potential and compare the results with the fermionic counterpart. In both cases the chiral symmetry group of the bosonic partition function is noncompact.

  14. A transition from a decelerated to an accelerated phase of the universe expansion from the simplest non-trivial polynomial function of T in the f(R,T) formalism

    CERN Document Server

    Moraes, P H R S; Correa, R A C

    2016-01-01

    In this work we present cosmological solutions from the simplest non-trivial $T$-dependence in $f(R,T)$ theory of gravity, with $R$ and $T$ standing for the Ricci scalar and trace of the energy-momentum tensor, respectively. Although such an approach yields a highly non-linear differential equation for the scale factor, we show that it is possible to obtain analytical solutions for the cosmological parameters. For some values of the free parameters, the model is able to predict a transition from a decelerated to an accelerated expansion of the universe.

  15. Dirac Bracket Quantization of Bosonized chiral QCD2

    International Nuclear Information System (INIS)

    We systematically derive the bosonized form of the chiral QCD2 Zagrangean exchibiting explicitely the anomalous breaking of gauge invariance and quantize it using Dirac's algorithm for constrained systems. As a side product we also discuss the Hamiltonean formalism for the principal sigma model, and derive the commutation relations of the chiral currents in both models. (author)

  16. Pragmatics for formal semantics

    DEFF Research Database (Denmark)

    Danvy, Olivier

    2011-01-01

    This tech talk describes how to write and how to inter-derive formal semantics for sequential programming languages. The progress reported here is (1) concrete guidelines to write each formal semantics to alleviate their proof obligations, and (2) simple calculational tools to obtain a formal sem...

  17. The Higgs boson

    OpenAIRE

    Pimenta, Jean Jûnio Mendes; Belussi, Lucas Francisco Bosso; Natti, Érica Regina Takano; Natti, Paulo Laerte

    2013-01-01

    The Higgs boson was predicted in 1964 by British physicist Peter Higgs. The Higgs is the key to explain the origin of the mass of other elementary particles of Nature. However, only with the coming into operation of the LHC, in 2008, there were technological conditions to search for the Higgs boson. Recently, a major international effort conducted at CERN, by means of ATLAS and CMS experiments, has enabled the observation of a new bosonic particle in the region of 125 GeVs. In this paper, by ...

  18. Photoproduction of leptophobic bosons

    CERN Document Server

    Fanelli, Cristiano

    2016-01-01

    We propose a search for photoproduction of leptophobic bosons that couple to quarks at the GlueX experiment at Jefferson Lab. We study in detail a new gauge boson that couples to baryon number $B$, and estimate that $\\gamma p \\to p B$ will provide the best sensitivity for $B$ masses above 0.5 GeV. This search will also provide sensitivity to other proposed dark-sector states that couple to quarks. Finally, our results motivate a similar search for $B$ boson electroproduction at the CLAS experiment.

  19. Entropy current formalism for supersymmetric theories

    Directory of Open Access Journals (Sweden)

    L. Andrianopoli

    2015-03-01

    Full Text Available The recent developments in fluid/gravity correspondence give a new impulse to the study of fluid dynamics of supersymmetric theories. In that respect, the entropy current formalism requires some modifications in order to be adapted to supersymmetric theories and supergravities. We formulate a new entropy current in superspace with the properties: 1 it is conserved off-shell for non-dissipative fluids, 2 it is invariant under rigid supersymmetry transformations, 3 it is covariantly closed in local supersymmetric theories, 4 it reduces to its bosonic expression on space–time.

  20. Approximate gauge symemtry of composite vector bosons

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Mahiko

    2010-06-01

    It can be shown in a solvable field theory model that the couplings of the composite vector mesons made of a fermion pair approach the gauge couplings in the limit of strong binding. Although this phenomenon may appear accidental and special to the vector bosons made of a fermion pair, we extend it to the case of bosons being constituents and find that the same phenomenon occurs in more an intriguing way. The functional formalism not only facilitates computation but also provides us with a better insight into the generating mechanism of approximate gauge symmetry, in particular, how the strong binding and global current conservation conspire to generate such an approximate symmetry. Remarks are made on its possible relevance or irrelevance to electroweak and higher symmetries.

  1. The bosonic birthday paradox

    CERN Document Server

    Arkhipov, Alex

    2011-01-01

    We motivate and prove a version of the birthday paradox for $k$ identical bosons in $n$ possible modes. If the bosons are in the uniform mixed state, also called the maximally mixed quantum state, then we need $k \\sim \\sqrt{n}$ bosons to expect two in the same state, which is smaller by a factor of $\\sqrt{2}$ than in the case of distinguishable objects (boltzmannons). While the core result is elementary, we generalize the hypothesis and strengthen the conclusion in several ways. One side result is that boltzmannons with a randomly chosen multinomial distribution have the same birthday statistics as bosons. This last result is interesting as a quantum proof of a classical probability theorem; we also give a classical proof.

  2. Driven Boson Sampling

    OpenAIRE

    Barkhofen, Sonja; Bartley, Tim J.; Sansoni, Linda; Kruse, Regina; Hamilton, Craig S.; Jex, Igor; Silberhorn, Christine

    2016-01-01

    Sampling the distribution of bosons that have undergone a random unitary evolution is strongly believed to be a computationally hard problem. Key to outperforming classical simulations of this task is to increase both the number of input photons and the size of the network. We propose driven boson sampling, in which photons are input within the network itself, as a means to approach this goal. When using heralded single-photon sources based on parametric down-conversion, this approach offers ...

  3. Higgs Boson Pizza Day

    CERN Multimedia

    Stefania Pandolfi

    2016-01-01

    CERN celebrated the fourth anniversary of the historical Higgs boson announcement with special pizzas.    400 pizzas were served on Higgs pizza day in Restaurant 1 at CERN to celebrate the fourth anniversary of the announcement of the discovery of the Higgs Boson (Image: Maximilien Brice/ CERN) What do the Higgs boson and a pizza have in common? Pierluigi Paolucci, INFN and CMS collaboration member, together with INFN president Fernando Ferroni found out the answer one day in Naples: the pizza in front of them looked exactly like a Higgs boson event display. A special recipe was then created in collaboration with the chef of the historic “Ettore” pizzeria in the St. Lucia area of Naples, and two pizzas were designed to resemble two Higgs boson decay channel event displays. The “Higgs Boson Pizza Day” was held on Monday, 4 July 2016, on the fourth anniversary of the announcement of the discovery of the Higgs boso...

  4. Higgs boson pizza

    CERN Multimedia

    Cinzia De Melis

    2016-01-01

    Four years after the historic announcement of the Higgs boson discovery at CERN, a collaboration between INFN and CERN has declared 4 July 2016 as “Higgs Boson Pizza Day”. The idea was born in Naples, by Pierluigi Paolucci and INFN president Fernando Ferroni, who inspired the chef of the historic “Ettore” pizzeria in St. Lucia to create the Higgs boson pizza in time for the opening of a Art&Science exhibition on 15 September 2015 in Naples. The animation shows the culinary creation of a Higgs boson in form of a vegetarian and ham&salami pizza. Ham&Salami: A two asparagus (proton-proton) collision produces a spicy Higgs boson (chorizo) decaying into two high-energy salami (photon) clusters and a lot of charged (sliced ham) and neutral (olive) particles that are detected in the pizza (detector) entirely covered with mozzarella sensors. A two asparagus (proton-proton) collision produces a juicy Higgs boson (cherry tomato) decaying into four high-energy (charged) peppers producing a tasty sign...

  5. Industrial use of formal methods formal verification

    CERN Document Server

    Boulanger, Jean-Louis

    2012-01-01

    At present the literature gives students and researchers of the very general books on the formal technics. The purpose of this book is to present in a single book, a return of experience on the used of the "formal technics" (such proof and model-checking) on industrial examples for the transportation domain. This book is based on the experience of people which are completely involved in the realization and the evaluation of safety critical system software based.  The implication of the industrialists allows to raise the problems of confidentiality which could appear and so allow

  6. Magnetoresistance and localization in bosonic insulators

    Science.gov (United States)

    Müller, Markus

    2013-06-01

    We study the strong localization of hard-core bosons. Using a locator expansion we find that in the insulator, unlike for typical fermion problems, nearly all low-energy scattering paths come with positive amplitudes and hence interfere constructively. As a consequence, the localization length of bosonic excitations shrinks when the constructive interference is suppressed by a magnetic field, entailing an exponentially large positive magnetoresistance, opposite to and significantly stronger than the analogous effect in fermions. Within the forward-scattering approximation, we find that the lowest-energy excitations are the most delocalized. A similar analysis applied to random field Ising models suggests that the ordering transition is due to a delocalization initiated at zero energy rather than due to the closure of a mobility gap in the paramagnet.

  7. Computing matrix permanent with collective boson operators

    CERN Document Server

    Huh, Joonsuk

    2016-01-01

    Computing permanents of matrices are known to be a classically hard problem that the computational cost grows exponentially with the size of the matrix increases. So far, there exist a few classical algorithms to compute the matrix permanents in deterministic and in randomized ways. By exploiting the series expansion of products of boson operators regarding collective boson operators, a generalized algorithm for computing permanents is developed that the algorithm can handle the arbitrary matrices with repeated columns and rows. In a particular case, the formula is reduced to Glynn's form. Not only the algorithm can be used for a deterministic direct calculation of the matrix permanent but also can be expressed as a sampling problem like Gurvits's randomized algorithm.

  8. Developments in Formal Proofs

    OpenAIRE

    Hales, Thomas C.

    2014-01-01

    This report describes three particular technological advances in formal proofs. The HOL Light proof assistant will be used to illustrate the design of a highly reliable system. Today, proof assistants can verify large bodies of advanced mathematics; and as an example, we turn to the formal proof in Coq of the Feit-Thompson Odd Order theorem in group theory. Finally, we discuss advances in the automation of formal proofs, as implemented in proof assistants such as Mizar, Coq, Isabelle, and HOL...

  9. Bosonic behavior of entangled fermions

    International Nuclear Information System (INIS)

    Two bound, entangled fermions form a composite boson, which can be treated as an elementary boson as long as the Pauli principle remains irrelevant. The bosonic character of the composite is intimately linked to the entanglement of the fermions: Large entanglement implies good bosonic properties. The deviation from perfect bosonic behavior manifests itself in the statistical properties of the composites and in their collective interference. As a consequence, the counting statistics exhibited by composites allow one to infer the form of the two-fermion wave-function. Bosonic behavior can thus be used as a probe for the underlying structure of composite particles without directly accessing their constituents.

  10. Thermal expansion

    International Nuclear Information System (INIS)

    Thermal expansion of fuel pellet is an important property which limits the lifetime of the fuels in reactors, because it affects both the pellet and cladding mechanical interaction and the gap conductivity. By fitting a number of available measured data, recommended equations have been presented and successfully used to estimate thermal expansion coefficient of the nuclear fuel pellet. However, due to large scatter of the measured data, non-consensus data have been omitted in formulating the equations. Also, the equation is strongly governed by the lack of appropriate experimental data. For those reasons, it is important to develop theoretical methodologies to better describe thermal expansion behaviour of nuclear fuel. In particular, first-principles and molecular dynamics simulations have been certainly contributed to predict reliable thermal expansion without fitting the measured data. Furthermore, the two theoretical techniques have improved on understanding the change of fuel dimension by describing the atomic-scale processes associated with lattice expansion in the fuels. (author)

  11. Anyons in the operational formalism

    International Nuclear Information System (INIS)

    The operational formalism to quantum mechanics seeks to base the theory on a firm foundation of physically well-motivated axioms [1]. It has succeeded in deriving the Feynman rules [2] for general quantum systems. Additional elaborations have applied the same logic to the question of identical particles, confirming the so-called Symmetrization Postulate [3]: that the only two options available are fermions and bosons [4, 5]. However, this seems to run counter to results in two-dimensional systems, which allow for anyons, particles with statistics which interpolate between Fermi-Dirac and Bose-Einstein (see [6] for a review). In this talk we will show that the results in two dimensions can be made compatible with the operational results. That is, we will show that anyonic behavior is a result of the topology of the space in two dimensions [7], and does not depend on the particles being identical; but that nevertheless, if the particles are identical, the resulting system is still anyonic

  12. Operator bosonization on Riemann surfaces: new vertex operators

    International Nuclear Information System (INIS)

    A new formalism is presented for building an operator theory of generalized ghost systems (bc theories of spin J) on Riemann surfaces (loop diagrams of the closed string theory). Operators of the bc system are expressed through the operators of a bosonic conformal theory on a Riemann surface. As distinct from standard bosonization formulas, which have meaning only locally, the Baker-Akhiezer operator functions are introduced which are globally well defined on a Riemann surface of arbitrary form. The operator algebra of Baker-Akhiezer functions generates explicity the algebraic-geometrical τ function and correlation functions of bc systems on Riemann surfaces

  13. A combinatorial construction of symplectic expansions

    CERN Document Server

    Kuno, Yusuke

    2010-01-01

    The notion of a symplectic expansion directly relates the topology of a surface to formal symplectic geometry. We give a method to construct a symplectic expansion by solving a recurrence formula given in terms of the Baker-Campbell-Hausdorff series.

  14. Software Formal Inspections Guidebook

    Science.gov (United States)

    1993-01-01

    The Software Formal Inspections Guidebook is designed to support the inspection process of software developed by and for NASA. This document provides information on how to implement a recommended and proven method for conducting formal inspections of NASA software. This Guidebook is a companion document to NASA Standard 2202-93, Software Formal Inspections Standard, approved April 1993, which provides the rules, procedures, and specific requirements for conducting software formal inspections. Application of the Formal Inspections Standard is optional to NASA program or project management. In cases where program or project management decide to use the formal inspections method, this Guidebook provides additional information on how to establish and implement the process. The goal of the formal inspections process as documented in the above-mentioned Standard and this Guidebook is to provide a framework and model for an inspection process that will enable the detection and elimination of defects as early as possible in the software life cycle. An ancillary aspect of the formal inspection process incorporates the collection and analysis of inspection data to effect continual improvement in the inspection process and the quality of the software subjected to the process.

  15. More than Formal Proof.

    Science.gov (United States)

    Hanna, Gila

    1989-01-01

    The origins of the emphasis on formal proof are discussed as well as more recent views. Factors in acceptance of a proof and the social process of acceptance by mathematicians are included. The impact of formal proof on the curriculum and implications for teaching are given. (DC)

  16. Bosonization of Weyl Fermions

    Science.gov (United States)

    Marino, Eduardo

    The electron, discovered by Thomson by the end of the nineteenth century, was the first experimentally observed particle. The Weyl fermion, though theoretically predicted since a long time, was observed in a condensed matter environment in an experiment reported only a few weeks ago. Is there any linking thread connecting the first and the last observed fermion (quasi)particles? The answer is positive. By generalizing the method known as bosonization, the first time in its full complete form, for a spacetime with 3+1 dimensions, we are able to show that both electrons and Weyl fermions can be expressed in terms of the same boson field, namely the Kalb-Ramond anti-symmetric tensor gauge field. The bosonized form of the Weyl chiral currents lead to the angle-dependent magneto-conductance behavior observed in these systems.

  17. Dynamical Boson Stars

    CERN Document Server

    Liebling, Steven L

    2012-01-01

    The idea of stable, localized bundles of energy has strong appeal as a model for particles. In the 1950s John Wheeler envisioned such bundles as smooth configurations of electromagnetic energy that he called {\\em geons}, but none were found. Instead, particle-like solutions were found in the late 1960s with the addition of a scalar field, and these were given the name {\\em boson stars}. Since then, boson stars find use in a wide variety of models as sources of dark matter, as black hole mimickers, in simple models of binary systems, and as a tool in finding black holes in higher dimensions with only a single killing vector. We discuss important varieties of boson stars, their dynamic properties, and some of their uses, concentrating on recent efforts.

  18. Dynamical Boson Stars

    Directory of Open Access Journals (Sweden)

    Steven L. Liebling

    2012-05-01

    Full Text Available The idea of stable, localized bundles of energy has strong appeal as a model for particles. In the 1950s, John Wheeler envisioned such bundles as smooth configurations of electromagnetic energy that he called geons, but none were found. Instead, particle-like solutions were found in the late 1960s with the addition of a scalar field, and these were given the name boson stars. Since then, boson stars find use in a wide variety of models as sources of dark matter, as black hole mimickers, in simple models of binary systems, and as a tool in finding black holes in higher dimensions with only a single Killing vector. We discuss important varieties of boson stars, their dynamic properties, and some of their uses, concentrating on recent efforts.

  19. Boson/Fermion Janus Particles

    CERN Document Server

    Tsekov, R

    2016-01-01

    Thermodynamically, bosons and fermions differ by their statistics only. A general entropy functional is proposed by superposition of entropic terms, typical for different quantum gases. The statistical properties of the corresponding Janus particles are derived by variation of the weight of the boson/fermion fraction. It is shown that di-bosons and anti-fermions separate in gas and liquid phases, while three-phase equilibrium appears for poly-boson/fermion Janus particles.

  20. Natural NMSSM Higgs bosons

    International Nuclear Information System (INIS)

    We study the phenomenology of Higgs bosons close to 126 GeV within the scale invariant unconstrained Next-to-Minimal Supersymmetric Standard Model (NMSSM), focusing on the regions of parameter space favoured by low fine-tuning considerations, namely stop masses of order 400 GeV to 1 TeV and an effective μ parameter between 100–200 GeV, with large (but perturbative) λ and low tanβ=2–4. We perform scans over the above parameter space, focusing on the observable Higgs cross sections into γγ, WW, ZZ, bb, ττ final states, and study the correlations between these observables. We show that the γγ signal strength may be enhanced up to a factor of about two not only due to the effect of singlet–doublet mixing, which occurs more often when the 126 GeV Higgs boson is the next-to-lightest CP-even one, but also due to light stops (and to a lesser extent light chargino and charged Higgs loops). There may be also smaller enhancements in the Higgs decay channels into WW, ZZ, correlated with the γγ enhancement. However there is no such correlation observed involving the Higgs decay channels into bb, ττ. The requirement of having perturbative couplings up to the GUT scale favours the interpretation of the 126 GeV Higgs boson as being the second lightest NMSSM CP-even state, which can decay into pairs of lighter neutralinos, CP-even or CP-odd Higgs bosons, leading to characteristic signatures of the NMSSM. In a non-negligible part of the parameter range the increase in the γγ rate is due to the superposition of rates from nearly degenerate Higgs bosons. Resolving these Higgs bosons would rule out the Standard Model, and provide evidence for the NMSSM

  1. Anomalous gauge boson interactions

    International Nuclear Information System (INIS)

    We discuss the direct measurement of the trilinear vector boson couplings in present and future collider experiments. The major goals of such experiments will be the confirmation of the Standard Model (SM) predictions and the search for signals of new physics. We review our current theoretical understanding of anomalous trilinear gauge-boson self interactions. If the energy scale of the new physics is ∼ 1 TeV, these low energy anomalous couplings are expected to be no larger than Ο(10-2). Constraints from high precision measurements at LEP and low energy charged and neutral current processes are critically reviewed

  2. Higgs boson hunting

    International Nuclear Information System (INIS)

    This is the summary report of the Higgs Boson Working Group. We discuss a variety of search techniques for a Higgs boson which is lighter than the Z. The processes K → πH, η prime → ηH,Υ → Hγ and e+e- → ZH are examined with particular attention paid to theoretical uncertainties in the calculations. We also briefly examine new features of Higgs phenomenology in a model which contains Higgs triplets as well as the usual doublet of scalar fields. 33 refs., 6 figs., 1 tab

  3. Nonexotic Neutral Gauge Bosons

    OpenAIRE

    Appelquist, Thomas; Dobrescu, Bogdan A.; Hopper, Adam R.

    2002-01-01

    We study theoretical and experimental constraints on electroweak theories including a new color-singlet and electrically-neutral gauge boson. We first note that the electric charges of the observed fermions imply that any such Z' boson may be described by a gauge theory in which the Abelian gauge groups are the usual hypercharge along with another U(1) component in a kinetic-diagonal basis. Assuming that the observed quarks and leptons have generation-independent U(1) charges, and that no new...

  4. Higgs boson hunting

    International Nuclear Information System (INIS)

    This paper is the summary report of the Higgs Boson Working Group. The authors discuss a variety of search techniques for a Higgs boson which is lighter than the Z. The processes K → πH, η' → ηH, Υ → Hγ and e+e- → ZH are examined with particular attention paid to theoretical uncertainties in the calculations. The authors also briefly examine new features of Higgs phenomenology in a model which contains Higgs triplets as well as the usual doublet of scalar fields

  5. Bosonic variables in nuclear matters

    International Nuclear Information System (INIS)

    It is shown that the boson theoretical interpretation of nuclear forces nessecitates the introduction of bosonic variables within the state function of nuclear matter. In this framework the 2-boson exchange plays a decisive role and calls for the introduction of special selfenergy diagrams. This generalized scheme is discussed with the help of a solvable field theoretical model. (orig.)

  6. A computer package for IBM-2 in the F-spin formalism

    International Nuclear Information System (INIS)

    A computer package for the neutron-proton interacting boson model is presented. It used the F-spin symmetric U(5) limit wavefunction as its basis states. Hamiltonian and other operators are written in terms of F-spin tonsorial form. In the input, in addition to the Hamiltonian forms in terms of neutron and proton bosons indices, F-spin tensorial formalism is also provided. B(M1) and B(E2) can also be calculated in the package

  7. Intermediate mass Higgs boson(s)

    International Nuclear Information System (INIS)

    Finding and understanding the spectrum of scalar bosons is the central problem of particle physics today. Considerable work has been done to learn how to study Standard Model heavy and obese Higgs bosons; simulations including the problems induced by standard model backgrounds are underway, and some results are reported elsewhere in these proceedings. The mass region MH Z/2 will be covered at SLC and LEP. LEPII will be able to extend this range to about 85 GeV. Above MH > 2MZ the search is easy for a Standard Model H degree at the SSC, though not so simple for the neutral scalars of a supersymmetric theory. The intermediate region, MZ/2 ≤ MH ≤ 2MZ is one of the most difficult mass regions to study, and it is the subject of this report. The authors concentrate on a neutral Standard Model scalar to be specific. The lightest scalar of a supersymmetric theory behaves very much like a Standard Model scalar for most ranges of parameters, so the results generally apply to that case as well, and for any form the scalar spectrum might take our results indicate how the analysis might go. Ultimately, to fully understand spontaneous symmetry breaking and the origin of mass, it will be necessary to find any intermediate mass scalar and to know in what mass ranges no scalars exist. Their analysis is only in progress, and their results reported here must be regarded as tentative

  8. Nonequilibrium functional bosonization of quantum wire networks

    Energy Technology Data Exchange (ETDEWEB)

    Ngo Dinh, Stephane, E-mail: stephane.ngodinh@kit.edu [Institut fuer Theorie der Kondensierten Materie, Karlsruhe Institute of Technology, 76128 Karlsruhe (Germany); DFG Center for Functional Nanostructures, Karlsruhe Institute of Technology, 76128 Karlsruhe (Germany); Bagrets, Dmitry A. [Institut fuer Theoretische Physik, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Koeln (Germany); Mirlin, Alexander D. [Institut fuer Theorie der Kondensierten Materie, Karlsruhe Institute of Technology, 76128 Karlsruhe (Germany); Institut fuer Nanotechnologie, Karlsruhe Institute of Technology, 76021 Karlsruhe (Germany); DFG Center for Functional Nanostructures, Karlsruhe Institute of Technology, 76128 Karlsruhe (Germany); Petersburg Nuclear Physics Institute, 188300 St. Petersburg (Russian Federation)

    2012-11-15

    We develop a general approach to nonequilibrium nanostructures formed by one-dimensional channels coupled by tunnel junctions and/or by impurity scattering. The formalism is based on nonequilibrium version of functional bosonization. A central role in this approach is played by the Keldysh action that has a form reminiscent of the theory of full counting statistics. To proceed with evaluation of physical observables, we assume the weak-tunneling regime and develop a real-time instanton method. A detailed exposition of the formalism is supplemented by two important applications: (i) tunneling into a biased Luttinger liquid with an impurity, and (ii) quantum Hall Fabry-Perot interferometry. - Highlights: Black-Right-Pointing-Pointer A nonequilibrium functional bosonization framework for quantum wire networks is developed Black-Right-Pointing-Pointer For the study of observables in the weak tunneling regime a real-time instanton method is elaborated. Black-Right-Pointing-Pointer We consider tunneling into a biased Luttinger liquid with an impurity. Black-Right-Pointing-Pointer We analyze electronic Fabry-Perot interferometers in the integer quantum Hall regime.

  9. Renyi entropies of free bosons on the torus and holography

    CERN Document Server

    Datta, Shouvik

    2014-01-01

    We analytically evaluate the Renyi entropies for the two dimensional free boson CFT. The CFT is considered to be compactified on a circle and at finite temperature. The Renyi entropies S_n are evaluated for a single interval using the two point function of bosonic twist fields on a torus. For the case of the compact boson, the sum over the classical saddle points results in the Riemann-Siegel theta function associated with the A_{n-1} lattice. We then study the Renyi entropies in the decompactification regime. We show that in the limit when the size of the interval becomes the size of the spatial circle, the entanglement entropy reduces to the thermal entropy of free bosons on a circle. We then set up a systematic high temperature expansion of the Renyi entropies and evaluate the finite size corrections for free bosons. Finally we compare these finite size corrections both for the free boson CFT and the free fermion CFT with the one-loop corrections obtained from bulk three dimensional handlebody spacetimes w...

  10. Mott-insulator and superfluid phases in the bosonic dynamical mean-field theory with the strong coupling impurity solver

    International Nuclear Information System (INIS)

    We investigate the phase diagram of correlated lattice bosons using the bosonic dynamical mean field theory (BDMFT). The BDMFT, formulated by Byczuk and Vollhardt (Phys. Rev. B 77, 235106 (2008)), is a comprehensive and thermodynamically consistent approximation in which the normal and condensed bosons are treated on equal footing. Within BDMFT the lattice bosonic problem is replaced by a single impurity coupled to two bosonic baths (corresponding to normal and condensed bosons, respectively). The resulting set of equations, the so-called ''impurity problem'', has to be solved self-consistently. Our approach is the strong coupling expansion within which the phase transition between the Mott-insulating superfluid phases can be described. Different thermodynamical quantities (particle density, compressibility, order parameter) as well as the bosonic density of states are investigated across the transition line.

  11. The Benefits of Formalization

    DEFF Research Database (Denmark)

    Rand, John; Torm, Nina Elisabeth

    2012-01-01

    Based on unique panel data consisting of both formal and informal firms, this paper uses a matched double difference approach to examine the relationship between legal status and firm level outcomes in micro, small and medium manufacturing enterprises (SMEs) in Vietnam. Controlling for determining...... factors and observable time-variant factors that may simultaneously influence the decision to formalize and subsequent firm performance, we find evidence that becoming officially registered leads to an increase in profits and investments, and a decrease in the use of casual labor (improved contract...... conditions for workers). Thus, we conclude that formalizing is beneficial both to firms and the workers in these firms....

  12. Towards the Fradkin-Vasiliev formalism in three dimensions

    CERN Document Server

    Zinoviev, Yu M

    2016-01-01

    In this paper we show that using frame-like gauge invariant formulation for the massive bosonic and fermionic fields in three dimensions the free Lagrangians for these fields can be rewritten in the explicitly gauge invariant form in terms of the appropriately chosen set of gauge invariant objects. This in turn opens the possibility to apply the Fradkin-Vasiliev formalism to the investigation of possible interactions of such fields.

  13. Higgs boson otherwise

    CERN Document Server

    Jora, Renata

    2009-01-01

    We propose an electroweak model based on the identification of the Higgs with the dilaton. We show that it is possible in this context to have a massless Higgs boson at tree and one loop levels without contradicting the main experimental and theoretical constraints.

  14. Z Bosons in LHCb

    CERN Document Server

    AUTHOR|(CDS)2077480; Müller, Katharina; Anderson, Jonathan

    In this thesis several measurements of the $Z$ boson production cross section in the LHCb detector are presented. After an introduction with the description of the underlying theory; the detector and the properties of the collisions the machine provided to us in LHC run I in Chapter 1, in Chapter 2 the details of the $Z$ reconstruction in the $Z\\rightarrow\\mu^+\\mu^-$ final state is discussed. In Chapter 3 jets are added to the $Z$ bosons. Several aspects of jet reconstruction are presented and a cross section measurement for the associated production of $Z$ bosons with jets at $\\sqrt{s}=7$ TeV is presented for two transverse momentum thresholds of the jets. In Chapter 4 the capability of the LHCb detector to reconstruct charmed mesons is used to establish a $ZD^{0}$ and a $ZD^{+}$ signal and to measure the total cross section. In Chapter 5 the cross section of inclusive $Z$ boson production is measured at a low statistics sample of $3.3~\\text{pb}^{-1}$ at $\\sqrt{s}=2.76$ TeV.

  15. Formal languages and compilation

    CERN Document Server

    Reghizzi, Stefano Crespi

    2009-01-01

    Covers the fundamental concepts of formal languages and compilation, which are central to computer science and based on well-consolidated principles. Based on definitions and algorithms, this book focuses on the importance of combining theoretical concepts with practical applications.

  16. Anisotropic expansion of a thermal dipolar Bose gas

    CERN Document Server

    Tang, Yijun; Burdick, Nathaniel Q; DiSciacca, Jack M; Petrov, Dmitry S; Lev, Benjamin L

    2016-01-01

    We report on the anisotropic expansion of ultracold bosonic dysprosium gases at temperatures above quantum degeneracy and develop a quantitative theory to describe this behavior. The theory expresses the post-expansion aspect ratio in terms of temperature and microscopic collisional properties by incorporating Hartree-Fock mean-field interactions, hydrodynamic effects, and Bose-enhancement factors. Our results extend the utility of expansion imaging by providing accurate thermometry for dipolar thermal Bose gases, reducing error in expansion thermometry from tens of percent to only a few percent. Furthermore, we present a simple method to determine scattering lengths in dipolar gases, including near a Feshbach resonance, through observation of thermal gas expansion.

  17. Long Range Correlation in Higgs Boson Plus Two Jets Production at the LHC

    CERN Document Server

    Sun, Peng; Yuan, Feng

    2016-01-01

    We study Higgs boson plus two high energy jets production at the LHC in the kinematics where the two jets are well separated in rapidity. The partonic processes are dominated by the t-channel weak boson fusion (WBF) and gluon fusion (GF) contributions. We derive the associated QCD resummation formalism for the correlation analysis where the total transverse momentum q_\\perp of the Higgs boson and two jets is small. Because of different color structures, the resummation results lead to distinguished behaviors: the WBF contribution peaks at relative low q_\\perp while all GF channel contributions are strongly de-correlated and spread to a much wider q_\\perp range. By applying a kinematic cut on q_\\perp, one can effectively increase the WBF signal to the GF background by a significant factor. This greatly strengthens the ability to investigate the WBF channel in Higgs boson production and study the couplings of Higgs to electroweak bosons.

  18. Scattering of stringy states in compactified closed bosonic string

    Science.gov (United States)

    Maharana, Jnanadeva

    2015-07-01

    We present scattering of stringy states of closed bosonic string compactified on torus Td. We focus our attention on scattering of moduli and gauge bosons. These states appear when massless excitations such as graviton and antisymmetric tensor field of the uncompactified theory are dimensionally reduced to lower dimension. The toroidally compactified theory is endowed with the T-duality symmetry, O (d, d). Therefore, it is expected that the amplitude for scattering of such states will be T-duality invariant. The formalism of Kawai-Lewellen-Tye is adopted and appropriately tailored to construct the vertex operators of moduli and gauge bosons. It is shown, in our approach, that N-point amplitude is T-duality invariant. We present illustrative examples for the four point amplitude to explicitly demonstrate the economy of our formalism when three spatial dimensions are compactified on T3. It is also shown that if we construct an amplitude with a set of 'initial' backgrounds, the T-duality operation transforms it to an amplitude associated with another set backgrounds. We propose a modified version of KLT approach to construct vertex operators for nonabelian massless gauge bosons which appear in certain compactification schemes.

  19. Scattering of stringy states in compactified closed bosonic string

    Directory of Open Access Journals (Sweden)

    Jnanadeva Maharana

    2015-07-01

    Full Text Available We present scattering of stringy states of closed bosonic string compactified on torus Td. We focus our attention on scattering of moduli and gauge bosons. These states appear when massless excitations such as graviton and antisymmetric tensor field of the uncompactified theory are dimensionally reduced to lower dimension. The toroidally compactified theory is endowed with the T-duality symmetry, O(d,d. Therefore, it is expected that the amplitude for scattering of such states will be T-duality invariant. The formalism of Kawai–Lewellen–Tye is adopted and appropriately tailored to construct the vertex operators of moduli and gauge bosons. It is shown, in our approach, that N-point amplitude is T-duality invariant. We present illustrative examples for the four point amplitude to explicitly demonstrate the economy of our formalism when three spatial dimensions are compactified on T3. It is also shown that if we construct an amplitude with a set of ‘initial’ backgrounds, the T-duality operation transforms it to an amplitude associated with another set backgrounds. We propose a modified version of KLT approach to construct vertex operators for nonabelian massless gauge bosons which appear in certain compactification schemes.

  20. The Parametrized Post-Newtonian-Vainshteinian Formalism

    CERN Document Server

    Avilez-Lopez, Ana; Saffin, Paul M; Skordis, Constantinos

    2015-01-01

    Light degrees of freedom that modify gravity on cosmological scales must be "screened" on solar system scales in order to be compatible with data. The Vainshtein mechanism achieves this through a breakdown of classical perturbation theory, as large interactions involving new degrees of freedom become important below the so-called Vainshtein radius. We begin to develop an extension of the Parameterized Post-Newtonian (PPN) formalism that is able to handle Vainshteinian corrections. We argue that theories with a unique Vainshtein scale must be expanded using two small parameters. In this Parameterized Post-Newtonian-Vainshteinian (PPNV) expansion, the primary expansion parameter that controls the PPN order is, as usual, the velocity $v$. The secondary expansion parameter, $\\alpha$, controls the strength of the Vainshteinian correction and is a theory-specific combination of the Schwarzschild radius and the Vainshtein radius of the source that is independent of its mass. We present the general framework and appl...

  1. Experimental Boson Sampling

    CERN Document Server

    Spring, Justin B; Humphreys, Peter C; Kolthammer, W Steven; Jin, Xian-Min; Barbieri, Marco; Datta, Animesh; Thomas-Peter, Nicholas; Langford, Nathan K; Kundys, Dmytro; Gates, James C; Smith, Brian J; Smith, Peter G R; Walmsley, Ian A

    2013-01-01

    While universal quantum computers ideally solve problems such as factoring integers exponentially more efficiently than classical machines, the formidable challenges in building such devices motivate the demonstration of simpler, problem-specific algorithms that still promise a quantum speedup. We construct a quantum boson sampling machine (QBSM) to sample the output distribution resulting from the nonclassical interference of photons in an integrated photonic circuit, a problem thought to be exponentially hard to solve classically. Unlike universal quantum computation, boson sampling merely requires indistinguishable photons, linear state evolution, and detectors. We benchmark our QBSM with three and four photons and analyze sources of sampling inaccuracy. Our studies pave the way to larger devices that could offer the first definitive quantum-enhanced computation.

  2. Interacting boson approximation

    International Nuclear Information System (INIS)

    Lectures notes on the Interacting Boson Approximation are given. Topics include: angular momentum tensors; properties of T/sub i//sup (n)/ matrices; T/sub i//sup (n)/ matrices as Clebsch-Gordan coefficients; construction of higher rank tensors; normalization: trace of products of two s-rank tensors; completeness relation; algebra of U(N); eigenvalue of the quadratic Casimir operator for U(3); general result for U(N); angular momentum content of U(3) representation; p-Boson model; Hamiltonian; quadrupole transitions; S,P Boson model; expectation value of dipole operator; S-D model: U(6); quadratic Casimir operator; an O(5) subgroup; an O(6) subgroup; properties of O(5) representations; quadratic Casimir operator; quadratic Casimir operator for U(6); decomposition via SU(5) chain; a special O(3) decomposition of SU(3); useful identities; a useful property of D/sub αβγ/(α,β,γ = 4-8) as coupling coefficients; explicit construction of T/sub x//sup (2)/ and d/sub αβγ/; D-coefficients; eigenstates of T3; and summary of T = 2 states

  3. Fear of the Formal

    DEFF Research Database (Denmark)

    du Gay, Paul; Lopdrup-Hjorth, Thomas

    could either be done under the headline ‘Gov 2.0’ that re-envisions the function of government as a platform around which creative citizens collaborate (O’Reilly, 2009), or by adopting a whole new mindset where a organo-centric view of the world is replaced by a more democratic, co-creative, ecosystem...... manifestation in relation to recent and ongoing reforms of organizational life and state administration. At the same time, we seek to indicate the continuing constitutive significance of formality and formalization for both the securing of organizational purposes and the individual freedom, and for ‘stateness...

  4. Formal Definition of AI

    OpenAIRE

    Dobrev, Dimiter

    2012-01-01

    A definition of Artificial Intelligence was proposed in [1] but this definition was not absolutely formal at least because the word "Human" was used. In this paper we will formalize the definition from [1]. The biggest problem in this definition was that the level of intelligence of AI is compared to the intelligence of a human being. In order to change this we will introduce some parameters to which AI will depend. One of this parameters will be the level of intelligence and we will define o...

  5. Formality theorem for gerbes

    DEFF Research Database (Denmark)

    Bressler, Paul; Gorokhovsky, Alexander; Nest, Ryszard;

    2015-01-01

    The main result of the present paper is an analogue of Kontsevich formality theorem in the context of the deformation theory of gerbes. We construct an L∞L∞ deformation of the Schouten algebra of multi-vectors which controls the deformation theory of a gerbe.......The main result of the present paper is an analogue of Kontsevich formality theorem in the context of the deformation theory of gerbes. We construct an L∞L∞ deformation of the Schouten algebra of multi-vectors which controls the deformation theory of a gerbe....

  6. Boson stars with nonminimal coupling

    CERN Document Server

    Marunovic, Anja

    2015-01-01

    Boson stars coupled to Einstein's general relativity possess some features similar to gravastars, such as the anisotropy in principal pressures and relatively large compactness ($\\mu_{max} = 0.32$). However, no matter how large the self-interaction is, the ordinary boson star cannot obtain arbitrarily large compression and as such does not represent a good black hole mimicker. When the boson star is nonminimally coupled to gravity, the resulting configurations resemble more the dark energy stars then the ordinary boson stars, with compactness significantly larger then that in ordinary boson stars (if matter is not constrained with the energy conditions). The gravitationally bound system of a boson star and a global monopole represents a good black hole mimicker.

  7. The Lorentz anomaly via operator product expansion

    International Nuclear Information System (INIS)

    The emergence of a critical dimension is one of the most striking features of string theory. One way to obtain it is by demanding closure of the Lorentz algebra in the light-cone gauge quantisation, as discovered for bosonic strings more than forty years ago. We give a detailed derivation of this classical result based on the operator product expansion on the Lorentzian world-sheet

  8. The Lorentz anomaly via operator product expansion

    Energy Technology Data Exchange (ETDEWEB)

    Fredenhagen, Stefan, E-mail: stefan.fredenhagen@aei.mpg.de [Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-Institut Am Mühlenberg 1, 14476 Golm (Germany); Hoppe, Jens, E-mail: hoppe@kth.se; Hynek, Mariusz, E-mail: mkhynek@kth.se [Department of Mathematics, Royal Institute of Technology, KTH 100 44 Stockholm (Sweden)

    2015-10-15

    The emergence of a critical dimension is one of the most striking features of string theory. One way to obtain it is by demanding closure of the Lorentz algebra in the light-cone gauge quantisation, as discovered for bosonic strings more than forty years ago. We give a detailed derivation of this classical result based on the operator product expansion on the Lorentzian world-sheet.

  9. Difficult-to-detect convergence problem of variational multi-mode quantum dynamics with attractive bosons

    OpenAIRE

    Cosme, Jayson G.; Weiss, Christoph; Brand, Joachim

    2015-01-01

    We test variational quantum dynamics with the multiconfigurational time-dependent Hartree method for bosons (MCTDHB) against exact solutions for the dynamics of two attractive bosons following trap release. MCTDHB produces unphysical and qualitatively incorrect results of breathing dynamics where ballistic expansion should occur, although an analysis of participating mode functions indicates that the numerical result should be converged. Further analysis reveals that the calculations are inde...

  10. Boson star at finite temperature

    CERN Document Server

    Latifah, S; Mart, T

    2014-01-01

    By using a simple thermodynamical method we confirm the finding of Chavanis and Harko that stable Bose-Einstein condensate stars can form. However, by using a thermodynamically consistent boson equation of state, we obtain a less massive Bose-Einstein condensate star compared to the one predicted by Chavanis and Harko. We also obtain that the maximum mass of a boson star is insensitive to the change of matter temperature. However, the mass of boson star with relatively large radius depends significantly on the temperature of the boson matter.

  11. Bosonization and Lie Group Structure

    CERN Document Server

    Ha, Yuan K

    2015-01-01

    We introduce a concise quantum operator formula for bosonization in which the Lie group structure appears in a natural way. The connection between fermions and bosons is found to be exactly the connection between Lie group elements and the group parameters. Bosonization is an extraordinary way of expressing the equation of motion of a complex fermion field in terms of a real scalar boson in two dimensions. All the properties of the fermion field theory are known to be preserved under this remarkable transformation with substantial simplification and elucidation of the original theory, much like Lie groups can be studied by their Lie algebras.

  12. Formality in Brackets

    DEFF Research Database (Denmark)

    Garsten, Christina; Nyqvist, Anette

    suits’ (Nyqvist 2013), and of doing ‘ethnography by failure’ (Garsten 2013). In this paper, we explore the layers of informality and formality in our fieldwork experiences among financial investors and policy experts, and discuss how to ethnographically represent embodied fieldwork practices. How do we...

  13. Formalization of Medical Guidelines

    Czech Academy of Sciences Publication Activity Database

    Peleška, Jan; Anger, Z.; Buchtela, David; Šebesta, K.; Tomečková, Marie; Veselý, Arnošt; Zvára, K.; Zvárová, Jana

    2005-01-01

    Roč. 1, - (2005), s. 133-141. ISSN 1801-5603 R&D Projects: GA AV ČR 1ET200300413 Institutional research plan: CEZ:AV0Z10300504 Keywords : GLIF model * formalization of guidelines * prevention of cardiovascular diseases Subject RIV: IN - Informatics, Computer Science

  14. Fear of the Formal

    DEFF Research Database (Denmark)

    du Gay, Paul; Lopdrup-Hjorth, Thomas

    2016-01-01

    term this ‘fear of the formal’, outlining key elements of its genealogy and exploring its contemporary manifestation in relation to recent and ongoing reforms of organisational life in a range of contexts. At the same time, we seek to indicate the continuing constitutive significance of formality...

  15. Links between the quantum Hall effect, chiral boson theories and string theory

    International Nuclear Information System (INIS)

    Chiral boson theory is introduced and its relevance to the quantum Hall effect is explained. It is shown that the chiral boson theory admits mode expansions which are essentially those which appear and are made use of in bosonic string theories. This immediately leads to a way of quantizing the theory. Restrictions on various parameters appearing in the model can be imposed in a natural way. Finally, it is suggested that some of these ideas have important applications to other geometries which could give rise to new types of physical behavior. (author)

  16. Approximate but accurate quantum dynamics from the Mori formalism: I. Nonequilibrium dynamics

    Science.gov (United States)

    Montoya-Castillo, Andrés; Reichman, David R.

    2016-05-01

    We present a formalism that explicitly unifies the commonly used Nakajima-Zwanzig approach for reduced density matrix dynamics with the more versatile Mori theory in the context of nonequilibrium dynamics. Employing a Dyson-type expansion to circumvent the difficulty of projected dynamics, we obtain a self-consistent equation for the memory kernel which requires only knowledge of normally evolved auxiliary kernels. To illustrate the properties of the current approach, we focus on the spin-boson model and limit our attention to the use of a simple and inexpensive quasi-classical dynamics, given by the Ehrenfest method, for the calculation of the auxiliary kernels. For the first time, we provide a detailed analysis of the dependence of the properties of the memory kernels obtained via different projection operators, namely, the thermal (Redfield-type) and population based (NIBA-type) projection operators. We further elucidate the conditions that lead to short-lived memory kernels and the regions of parameter space to which this program is best suited. Via a thorough analysis of the different closures available for the auxiliary kernels and the convergence properties of the self-consistently extracted memory kernel, we identify the mechanisms whereby the current approach leads to a significant improvement over the direct usage of standard semi- and quasi-classical dynamics.

  17. Approximate but Accurate Quantum Dynamics from the Mori Formalism: I. Nonequilibrium Dynamics

    CERN Document Server

    Montoya-Castillo, Andrés

    2016-01-01

    We present a formalism that explicitly unifies the commonly used Nakajima-Zwanzig approach for reduced density matrix dynamics with the more versatile Mori theory in the context of nonequilibrium dynamics. Employing a Dyson-type expansion to circumvent the difficulty of projected dynamics, we obtain a self-consistent equation for the memory kernel which requires only knowledge of normally evolved auxiliary kernels. To illustrate the properties of the current approach, we focus on the spin-boson model and limit our attention to the use of a simple and inexpensive quasi-classical dynamics, given by the Ehrenfest method, for the calculation of the auxiliary kernels. For the first time, we provide a detailed analysis of the dependence of the properties of the memory kernels obtained via different projection operators, namely the thermal (Redfield-type) and population based (NIBA-type) projection operators. We further elucidate the conditions that lead to short-lived memory kernels and the regions of parameter spa...

  18. Approximate but accurate quantum dynamics from the Mori formalism: I. Nonequilibrium dynamics.

    Science.gov (United States)

    Montoya-Castillo, Andrés; Reichman, David R

    2016-05-14

    We present a formalism that explicitly unifies the commonly used Nakajima-Zwanzig approach for reduced density matrix dynamics with the more versatile Mori theory in the context of nonequilibrium dynamics. Employing a Dyson-type expansion to circumvent the difficulty of projected dynamics, we obtain a self-consistent equation for the memory kernel which requires only knowledge of normally evolved auxiliary kernels. To illustrate the properties of the current approach, we focus on the spin-boson model and limit our attention to the use of a simple and inexpensive quasi-classical dynamics, given by the Ehrenfest method, for the calculation of the auxiliary kernels. For the first time, we provide a detailed analysis of the dependence of the properties of the memory kernels obtained via different projection operators, namely, the thermal (Redfield-type) and population based (NIBA-type) projection operators. We further elucidate the conditions that lead to short-lived memory kernels and the regions of parameter space to which this program is best suited. Via a thorough analysis of the different closures available for the auxiliary kernels and the convergence properties of the self-consistently extracted memory kernel, we identify the mechanisms whereby the current approach leads to a significant improvement over the direct usage of standard semi- and quasi-classical dynamics. PMID:27179468

  19. Higher Spin Particles with Bosonic Counterpart of Supersymmetry

    CERN Document Server

    Fedoruk, S; Fedoruk, Sergey; Lukierski, Jerzy

    2005-01-01

    We propose the relativistic point particle models invariant under the bosonic counterpart of SUSY. The particles move along the world lines in four dimensional Minkowski space extended by $N$ commuting Weyl spinors. The models provide after first quantization the non--Grassmann counterpart of chiral superfields, satisfying Klein--Gordon equation. Free higher spin fields obtained by expansions of such chiral superfields satisfy the N=2 Bargman--Wigner equations in massive case and Fierz--Pauli equations in massless case.

  20. Higgs boson cosmology

    CERN Document Server

    Moss, Ian G

    2015-01-01

    The discovery of the Standard Model Higgs boson opens up a range of speculative cosmological scenarios, from the formation of structure in the early universe immediately after the big bang, to relics from the electroweak phase transition one nanosecond after the big bang, on to the end of the present-day universe through vacuum decay. Higgs physics is wide-ranging, and gives an impetus to go beyond the Standard Models of particle physics and cosmology to explore the physics of ultra-high energies and quantum gravity.

  1. Compact boson stars

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Betti [School of Engineering and Science, Jacobs University, Postfach 750 561, D-28725 Bremen (Germany); Kleihaus, Burkhard; Kunz, Jutta [Institut fuer Physik, Universitaet Oldenburg, Postfach 2503, D-26111 Oldenburg (Germany); Schaffer, Isabell, E-mail: i.schaffer@jacobs-university.de [School of Engineering and Science, Jacobs University, Postfach 750 561, D-28725 Bremen (Germany)

    2012-07-24

    We consider compact boson stars that arise for a V-shaped scalar field potential. They represent a one parameter family of solutions of the scaled Einstein-Gordon equations. We analyze the physical properties of these solutions and determine their domain of existence. Along their physically relevant branch emerging from the compact Q-ball solution, their mass increases with increasing radius. Employing arguments from catastrophe theory we argue that this branch is stable, until the maximal value of the mass is reached. There the mass and size are on the order of magnitude of the Schwarzschild limit, and thus the spiraling respectively oscillating behaviour, well known for compact stars, sets in.

  2. Z' Bosons and Supersymmetry

    OpenAIRE

    Lykken, Joseph D.

    1996-01-01

    A broad class of supersymmetric extensions of the standard model predict a Z' vector boson whose mass is naturally in the range 250 GeV < M_Z' < 2 TeV. To avoid unacceptably large mixing with the Z, one requires either a discrete tuning of the U(1)' charges or a leptophobic Z'. Both cases are likely to arise as the low energy limits of heterotic string compactifications, but a survey of existing realistic string models provides no acceptable examples. A broken U(1)' leads to additional D-term...

  3. Robust determination of the scalar boson couplings

    CERN Document Server

    Corbett, Tyler; Gonzalez-Fraile, J; Gonzalez-Garcia, M C

    2013-01-01

    We study the indirect effects of new physics on the phenomenology of the "Higgs-like" particle. Assuming that the recently observed state belongs to a light electroweak doublet scalar and that the SU(2)_L x U(1)_Y symmetry is linearly realized, we parametrize these effects in terms of an effective Lagrangian at the electroweak scale. We choose the dimension--six operator basis which allows us to make better use of all the available data to constrain the coefficients of the dimension-six operators. We perform a global 6--parameter fit which allows simultaneous determination of the standard model scalar couplings to gluons, electroweak gauge bosons, bottom quarks, and tau leptons. The results are based on the data released at Moriond 2013. Moreover, our formalism leads to strong constraints on the electroweak triple gauge boson couplings. Note added: The analysis has been updated with a NEW GLOBAL 6-PARAMETER FIT with all the public data available after Moriond 2013. Updates of this analysis are provided at the...

  4. Composite gauge-bosons made of fermions

    Science.gov (United States)

    Suzuki, Mahiko

    2016-07-01

    We construct a class of Abelian and non-Abelian local gauge theories that consist only of matter fields of fermions. The Lagrangian is local and does not contain an auxiliary vector field nor a subsidiary condition on the matter fields. It does not involve an extra dimension nor supersymmetry. This Lagrangian can be extended to non-Abelian gauge symmetry only in the case of SU(2) doublet matter fields. We carry out an explicit diagrammatic computation in the leading 1 /N order to show that massless spin-one bound states appear with the correct gauge coupling. Our diagram calculation exposes the dynamical features that cannot be seen in the formal auxiliary vector-field method. For instance, it shows that the s -wave fermion-antifermion interaction in the 3S1 channel (ψ ¯ γμψ ) alone cannot form the bound gauge bosons; the fermion-antifermion pairs must couple to the d -wave state too. One feature common to our class of Lagrangian is that the Noether current does not exist. Therefore it evades possible conflict with the no-go theorem of Weinberg and Witten on the formation of the non-Abelian gauge bosons.

  5. Chemical graph-theoretic cluster expansions

    International Nuclear Information System (INIS)

    A general computationally amenable chemico-graph-theoretic cluster expansion method is suggested as a paradigm for incorporation of chemical structure concepts in a systematic manner. The cluster expansion approach is presented in a formalism general enough to cover a variety of empirical, semiempirical, and even ab initio applications. Formally such approaches for the utilization of chemical structure-related concepts may be viewed as discrete analogues of Taylor series expansions. The efficacy of the chemical structure concepts then is simply bound up in the rate of convergence of the cluster expansions. In many empirical applications, e.g., boiling points, chromatographic separation coefficients, and biological activities, this rate of convergence has been observed to be quite rapid. More note will be made here of quantum chemical applications. Relations to questions concerning size extensivity of energies and size consistency of wave functions are addressed

  6. Formalizations of Commonsense Psychology

    OpenAIRE

    Gordon, Andrew S.; Hobbs, Jerry R.

    2004-01-01

    The central challenge in commonsense knowledge representation research is to develop content theories that achieve a high degree of both competency and coverage. We describe a new methodology for constructing formal theories in commonsense knowledge domains that complements traditional knowledge representation approaches by first addressing issues of coverage. We show how a close examination of a very general task (strategic planning) leads to a catalog of the concepts and facts that must be ...

  7. {\\delta}N formalism

    OpenAIRE

    Sugiyama, Naonori S.; Komatsu, Eiichiro; Futamase, Toshifumi

    2012-01-01

    Precise understanding of nonlinear evolution of cosmological perturbations during inflation is necessary for the correct interpretation of measurements of non-Gaussian correlations in the cosmic microwave background and the large-scale structure of the universe. The "{\\delta}N formalism" is a popular and powerful technique for computing non-linear evolution of cosmological perturbations on large scales. In particular, it enables us to compute the curvature perturbation, {\\zeta}, on large scal...

  8. Nuclear orientation formalism

    International Nuclear Information System (INIS)

    The formalism necessary for the description, analysis and interpretation of experiments with oriented nuclei is considered in detail. The formalism is conveniently expressed as a sum of products where the number of terms appearing in the summation is determined by the spins of the nuclear levels and by the properties of the observed radiation. Each term of the product is identified with one particular aspect of the process which leads from the initial oriented state to the observed radiation. The orientation parameters and statistical tensors, used to describe the initial state, are discussed. The effective orientation is determined by the initial orientation modified by the deorientation coefficients. Further modifications, due to direct interactions of the electromagnetic moments of that state with the nuclear environment, are described by perturbation coefficients. The observed radiation is described by the angular distribution coefficients which depend on the multipole character of the observed radiation. Applications for various types of radiations are considered. Examples are given of angular correlation measurements, in which two radiations, e.g in a cascade, are measured in coincidence. Modifications of the standard angular distribution formalism, brought about by the finite size of the sources and detectors, are discussed. (Auth.)

  9. Hierarchy in Sampling Gaussian-correlated Bosons

    CERN Document Server

    Huh, Joonsuk

    2016-01-01

    Boson Sampling represents a class of physical processes potentially intractable for classical devices to simulate. The Gaussian extension of Boson Sampling remains a computationally hard problem, where the input state is a product of uncorrelated Gaussian modes. Besides, motivated by molecular spectroscopy, Vibronic Boson Sampling involves operations that can generate Gaussian correlation among different Boson modes. Therefore, Gaussian Boson Sampling is a special case of Vibronic Boson Sampling. However, this does not necessarily mean that Vibronic Boson Sampling is more complex than Gaussian Boson Sampling. Here we develop a hierarchical structure to show how the initial correlation in Vibronic Boson Sampling can be absorbed in Gaussian Boson Sampling with ancillary modes and in a scattershot fashion. Since every Gaussian state is associated with a thermal state, our result implies that every sampling problem in molecular vibronic transitions, at any temperature, can be simulated by Gaussian Boson Sampling ...

  10. A Minimally Symmetric Higgs Boson

    CERN Document Server

    Low, Ian

    2014-01-01

    Models addressing the naturalness of a light Higgs boson typically employ symmetries, either bosonic or fermionic, to stabilize the Higgs mass. We consider a setup with the minimal amount of symmetries: four shift symmetries acting on the four components of the Higgs doublet, subject to the constraints of linearly realized SU(2)xU(1) electroweak symmetry. Up to terms that explicitly violate the shift symmetries, the effective lagrangian can be derived, irrespective of the spontaneously broken group G in the ultraviolet, and is universal in all models where the Higgs arises as a pseudo-Nambu-Goldstone boson (PNGB). Very high energy scatterings of vector bosons could provide smoking gun signals of a minimally symmetric Higgs boson.

  11. Hard-core lattice bosons: new insights from algebraic graph theory

    Science.gov (United States)

    Squires, Randall W.; Feder, David L.

    2014-03-01

    Determining the characteristics of hard-core lattice bosons is a problem of long-standing interest in condensed matter physics. While in one-dimensional systems the ground state can be formally obtained via a mapping to free fermions, various properties (such as correlation functions) are often difficult to calculate. In this work we discuss the application of techniques from algebraic graph theory to hard-core lattice bosons in one dimension. Graphs are natural representations of many-body Hamiltonians, with vertices representing Fock basis states and edges representing matrix elements. We prove that the graphs for hard-core bosons and non-interacting bosons have identical connectivity; the only difference is the existence of edge weights. A formal mapping between the two is therefore possible by manipulating the graph incidence matrices. We explore the implications of these insights, in particular the intriguing possibility that ground-state properties of hard-core bosons can be calculated directly from those of non-interacting bosons.

  12. $\\delta N$ formalism from superpotential and holography

    CERN Document Server

    Garriga, Jaume; Vernizzi, Filippo

    2016-01-01

    We consider the superpotential formalism to describe the evolution of scalar fields during inflation, generalizing it to include the case with non-canonical kinetic terms. We provide a characterization of the attractor behaviour of the background evolution in terms of first and second slow-roll parameters (which need not be small). We find that the superpotential is useful in justifying the separate universe approximation from the gradient expansion, and also in computing the spectra of primordial perturbations around attractor solutions in the $\\delta N$ formalism. As an application, we consider a class of models where the background trajectories for the inflaton fields are derived from a product separable superpotential. In the perspective of the holographic inflation scenario, such models are dual to a deformed CFT boundary theory, with $D$ mutually uncorrelated deformation operators. We compute the bulk power spectra of primordial adiabatic and entropy cosmological perturbations, and show that the results...

  13. Scattering of Stringy States in Compactified Closed Bosonic String

    CERN Document Server

    Maharana, Jnanaveda

    2014-01-01

    We present scattering of stringy states of closed bosonic string compactified on d-dimensional torus. We focus our attention on scattering of moduli and gauge bosons. These states appear when massless excitations such as graviton and antisymmetric tensor field of the uncompactified theory are dimensionally reduced to lower dimension. The toroidally compactified theory is endowed with the T-duality symmetry, O(d,d). Therefore, it is expected that the amplitude for scattering of such states will be $T$-duality invariant. The formalism of Kawai-Llewelen-Tye is adopted and appropriately tailored to construct the vertex operators of moduli and gauge bosons. It is shown, in our approach, that N-point amplitude is T-duality invariant. We present illustrative examples for the four point amplitude to explicitly demonstrate the economy of our formalism when three spatial dimensions are compactified on three dimensional torus. It is also shown that if we construct an amplitude with a set of 'initial' backgrounds, the T-...

  14. Time-dependent many-body treatment of electron-boson dynamics: Application to plasmon-accompanied photoemission

    Science.gov (United States)

    Schüler, M.; Berakdar, J.; Pavlyukh, Y.

    2016-02-01

    Recent experiments access the time-resolved photoelectron signal originating from plasmon satellites in correlated materials and address their buildup and decay in real time. Motivated by these developments, we present the Kadanoff-Baym formalism for the nonequilibrium time evolution of interacting fermions and bosons. In contrast to the fermionic case, the bosons are described by second-order differential equations. Solution of the bosonic Kadanoff-Baym equations—which is the central ingredient of this work—requires substantial modification of the usual two-times electronic propagation scheme. The solution is quite general and can be applied to a number of problems, such as the interaction of electrons with quantized photons, phonons, and other bosonic excitations. Here the formalism is applied to the photoemission from a deep core hole accompanied by plasmon excitation. We compute the time-resolved photoelectron spectra and discuss the effects of intrinsic and extrinsic electron energy losses and their interference.

  15. Constraints and period relations in bosonic strings at genus-g

    CERN Document Server

    Oh, C H

    1994-01-01

    We examine some of the implications of implementing the usual boundary conditions on the closed bosonic string in the hamiltonian framework. Using the KN formalism, it is shown that at the quantum level, the resulting constraints lead to relations among the periods of the basis 1-forms. These are compared with those of Riemanns' which arise from a different consideration.

  16. New Results on Charged Compact Boson Stars

    CERN Document Server

    Kumar, Sanjeev; Kulshreshtha, Daya Shankar

    2016-01-01

    In this work we present some new results which we have obtained in a study of the phase diagram of charged compact boson stars in the theory involving massive complex scalar fields coupled to the U(1) gauge field and gravity in a conical potential in the presence of a cosmological constant $\\Lambda$ which we treat as a free parameter taking positive and negative values and thereby allowing us to study the theory in the de Sitter and Anti de Sitter spaces respectively. In our studies, we obtain four bifurcation points (possibility of more bifurcation points being not ruled out) in the de Sitter region. We present a detailed discussion of the various regions in our phase diagram with respect to four bifurcation points. Our theory is seen to have rich physics in a particular domain for positive values of $\\Lambda$ which is consistent with the accelerated expansion of the universe.

  17. New results on charged compact boson stars

    Science.gov (United States)

    Kumar, Sanjeev; Kulshreshtha, Usha; Kulshreshtha, Daya Shankar

    2016-05-01

    In this work we present some new results that we have obtained in a study of the phase diagram of charged compact boson stars in the theory involving massive complex scalar fields coupled to the U(1) gauge field and gravity in a conical potential in the presence of a cosmological constant Λ , which we treat as a free parameter taking positive and negative values and thereby allowing us to study the theory in de Sitter and anti de Sitter spaces, respectively. We obtain four bifurcation points (the possibility of more bifurcation points not being ruled out) in the de Sitter region. We present a detailed discussion of the various regions in our phase diagram with respect to four bifurcation points. Our theory is seen to have rich physics in a particular domain for positive values of Λ , which is consistent with the accelerated expansion of the Universe.

  18. Formalizing the concept of sound.

    Energy Technology Data Exchange (ETDEWEB)

    Kaper, H. G.; Tipei, S.

    1999-08-03

    The notion of formalized music implies that a musical composition can be described in mathematical terms. In this article we explore some formal aspects of music and propose a framework for an abstract approach.

  19. Formal Methods in Industry

    Directory of Open Access Journals (Sweden)

    Alexei Serna A.

    2012-12-01

    Full Text Available The application of formal methods in industry has progressed extensively over the past decade and the results are promising. But despite these achievements and it have been documented in numerous studies, it is still very common the skepticism about its usefulness and applicability. The goal of this paper is to show that its evolution over the past decade exceeds all previous processes and each time they do a better job to satisfy industrial needs. This is achieved by the description of some experiments and the result of various applications in industry and through an analyzing of the needs of companies that must be satisfy the research community in this field.

  20. Advanced formal verification

    CERN Document Server

    Drechsler, Rolf

    2007-01-01

    Preface. Contributing Authors. Introduction; R. Drechsler. 1. Formal Verification. 2. Challenges. 3. Contributions to this Book. 1: What SAT-Solvers Can and Cannot Do; E. Goldberg. 1. Introduction. 2. Hard Equivalence Checking CNF Formulas. 3. Stable Sets of Points. 2: Advancements in Mixed BDD and SAT Techniques; G. Cabodi, S. Quer. 1. Introduction. 2. Background. 3. Comparing SAT and BDD Approaches: Are they Different? 4. Decision Diagrams as a Slave Engine in General SAT: Clause Compression by Means of ZBDDs. 5. Decision Diagram Preprocessing and Circuit-Based SAT. 6. Using SAT in Symbolic

  1. Covariant map between Ramond-Neveu-Schwarz and pure spinor formalisms for the superstring

    International Nuclear Information System (INIS)

    A covariant map between the Ramond-Neveu-Schwarz (RNS) and pure spinor formalisms for the superstring is found which transforms the RNS and pure spinor BRST operators into each other. The key ingredient is a dynamical twisting of the ten spin-half RNS fermions into five spin-one and five spin-zero fermions using bosonic pure spinors that parameterize an SO(10)/U(5) coset. The map relates massless vertex operators in the two formalisms, and gives a new description of Ramond states which does not require spin fields. An argument is proposed for relating the amplitude prescriptions in the two formalisms

  2. Formal methods in knowledge engineering.

    OpenAIRE

    Harmelen, van, F.; Fensel, D.

    2007-01-01

    This paper presents a general discussion of the role of formal methods in Knowledge Engineering. We give an historical account of the development of the field of Knowledge Engineering towards the use of formal methods. Subsequently, we discuss the pro's and cons of formal methods. We do this by summarising the proclaimed advantages, and by arguing against some of the commonly heard objections against formal methods. We briefly summarise the current state of the art and discuss the most import...

  3. The Higgs boson

    CERN Multimedia

    Brunet, S

    2014-01-01

    ATLAS Higgs poster targeted to general public, explaining the Brout-Englert-Higgs mechanism and why it is important. It also explains the role of the Higgs Boson, how we look for it, the journey of the discovery and what comes after the discovery. Also available in French (http://cds.cern.ch/record/1697501). Don’t hesitate to use it in your institute’s corridors and in your outreach events! The poster is in A0 format. You can click on the image to download the high-quality .pdf version and print it at your favorite printshop. For any questions or comments you can contact atlas-outreach-coordination@cern.ch.

  4. The Z boson

    International Nuclear Information System (INIS)

    The discovery of the Z boson 7 years ago verified a key prediction of the unified theory of electromagnetic and weak forces. Today an experimental program is beginning at two electron-positron colliders to study the properties of the Z particle in great detail. The data accumulated will subject the unified theory to more rigorous tests and will probe with great sensitivity for new physics not encompassed by the existing standard model of the elementary particles and forces. Questions under study include the number of quark and lepton families, the mass of the still undiscovered top quark, and the search for the still unknown fifth force of nature required by the theory to generate the masses of the elementary particles. 48 refs., 3 figs., 1 tab

  5. Quartic gauge boson couplings

    Science.gov (United States)

    He, Hong-Jian

    1998-08-01

    We review the recent progress in studying the anomalous electroweak quartic gauge boson couplings (QGBCs) at the LHC and the next generation high energy e±e- linear colliders (LCs). The main focus is put onto the strong electroweak symmetry breaking scenario in which the non-decoupling guarantees sizable new physics effects for the QGBCs. After commenting upon the current low energy indirect bounds and summarizing the theoretical patterns of QGBCs predicted by the typical resonance/non-resonance models, we review our systematic model-independent analysis on bounding them via WW-fusion and WWZ/ZZZ-production. The interplay of the two production mechanisms and the important role of the beam-polarization at the LCs are emphasized. The same physics may be similarly and better studied at a multi-TeV muon collider with high luminosity.

  6. una experiencia no formal

    Directory of Open Access Journals (Sweden)

    Peter J. Scott

    2008-01-01

    Full Text Available En este documento presentamos parte de un estudio en el que se ha analizado un proceso de aprendizaje desarrollado por estudiantes en interacción directa a través de un entorno de videoconferencia. El estudio cubre un periodo de 6 meses de interacción de un grupo de estudiantes de animación gráfica en diferentes países, quienes han llevado a cabo un total de 99 reuniones. Cada una de estas reuniones ha sido organizada y manejada por la propia comunidad de estudiantes. Al final, los integrantes de la comunidad aparecen como sus propios mentores naturales, y el grupo muestra una enorme capacidad de apoyo mutuo y de asunción de roles de facilitación mutua en el contexto de dicho intercambio. En este estudio podemos ver cómo los estudiantes pueden apoyarse mutuamente de manera eficiente en un contexto de colaboración no formal y además podemos observar cómo sistemas de videoconferencia en red pueden ayudar a facilitar y transformar una comunidad de aprendizaje, incluso sin la intervención formal de aulas o profesores.

  7. Topological quantization of the free massive bosonic field

    CERN Document Server

    Arciniega, Gustavo; Patiño, Leonardo; Quevedo, Hernando

    2012-01-01

    We present the results of studding free massive bosonic fields under the formalism of topological quantization. First, we identify certain harmonic map as a geometric representation of this physical system. We take as a concrete example the case of free massive bosonic fields in two dimensions represented by the minimal embedding of a two dimensional surface into a pp-wave spacetime. We use this geometric representation to construct the fiber bundle corresponding to some specific field configurations and then find their topological spectra, defined as the integral of the Euler characteristic class. The integral of the Euler invariant turns out to be dependent on the order in which the variables are integrated. We discuss the results for some particular configurations and their consequences for the energy of the system.

  8. Unintegrated parton distributions and electroweak boson production at hadron colliders

    CERN Document Server

    Watt, G; Ryskin, M G

    2004-01-01

    We describe the use of doubly-unintegrated parton distributions in hadron-hadron collisions, using the (z,k_t)-factorisation prescription where the transverse momentum of the incoming parton is generated in the last evolution step. We apply this formalism to calculate the transverse momentum (P_T) distributions of produced W and Z bosons and compare the predictions to Tevatron Run 1 data. We find that the observed P_T distributions can be generated almost entirely by the leading order q_1 q_2 -> W,Z subprocesses, using known and universal doubly-unintegrated quark distributions. We also calculate the P_T distribution of the Standard Model Higgs boson at the LHC, where the dominant production mechanism is by gluon-gluon fusion.

  9. Radial expansion for spinning conformal blocks

    CERN Document Server

    Costa, Miguel$uPorto U.; Penedones, João; Trevisani, Emilio

    2016-01-01

    This paper develops a method to compute any bosonic conformal block as a series expansion in the optimal radial coordinate introduced by Hogervorst and Rychkov. The method reduces to the known result when the external operators are all the same scalar operator, but it allows to compute conformal blocks for external operators with spin. Moreover, we explain how to write closed form recursion relations for the coefficients of the expansions. We study three examples of four point functions in detail: one vector and three scalars; two vectors and two scalars; two spin 2 tensors and two scalars. Finally, for the case of two external vectors, we also provide a more efficient way to generate the series expansion using the analytic structure of the blocks as a function of the scaling dimension of the exchanged operator.

  10. Sudakov Resummation in Small-x Saturation Formalism

    OpenAIRE

    Mueller, A. H.; Xiao, Bo-Wen; Yuan, Feng

    2012-01-01

    Through an explicit calculation of massive scalar particle (e.g., Higgs boson) production in high energy pA collisions up to one-loop order, we demonstrate that the Sudakov-type logarithms in hard processes in small-x saturation formalism can be systematically separated from the typical small-x logarithms. The generic feature of the Sudakov logarithms and all order resummation is derived. We further comment on the phenomenological implications and extension to other hard processes in the smal...

  11. The W boson weighs in

    International Nuclear Information System (INIS)

    It was 20 years ago this month that particle physicists caught their first glimpse of the W boson. Now they have measured its mass so precisely that the Standard Model is facing an unprecedented challenge. (U.K.)

  12. Spectroscopy of family gauge bosons

    International Nuclear Information System (INIS)

    Spectroscopy of family gauge bosons is investigated based on a U(3) family gauge boson model proposed by Sumino. In his model, the family gauge bosons are in mass eigenstates in a diagonal basis of the charged lepton mass matrix. Therefore, the family numbers are defined by (e1,e2,e3)=(e,μ,τ), while the assignment for quark sector are free. For possible family-number assignments (q1,q2,q3), under a constraint from K0–K¯0 mixing, we investigate possibilities of new physics, e.g. production of the lightest family gauge boson at the LHC, μ−N→e−N, rare K and B decays, and so on.

  13. From Bosonic Strings to Fermions

    OpenAIRE

    Sidharth, B. G.

    2006-01-01

    Early string theory described Bosonic particles at the real life Compton scale. Later developments to include Fermions initiated by Ramond and others have lead through Quantum Super Strings to M-theory operating at the as yet experimentally unattainable Planck scale. We describe an alternative route from Bosonic Strings to Fermions, by directly invoking a non commutative geometry, an approach which is closer to experiment.

  14. Hidden order in bosonic gases confined in one-dimensional optical lattices

    International Nuclear Information System (INIS)

    We analyze the effective Hamiltonian arising from a suitable power series expansion of the overlap integrals of Wannier functions for confined bosonic atoms in a one-dimensional (1D) optical lattice. For certain constraints between the coupling constants, we construct an explicit relationship between such an effective bosonic Hamiltonian and the integrable spin-S anisotropic Heisenberg model. The former results are therefore integrable by construction. The field theory is governed by an anisotropic nonlinear σ-model with singlet and triplet massive excitations; this result holds also in the generic non-integrable cases. The criticality of the bosonic system is investigated. The schematic phase diagram is drawn. Our study sheds light on the hidden symmetry of the Haldane type for 1D bosons.

  15. Some tree-level string amplitudes in the NSR formalism

    CERN Document Server

    Becker, Katrin; Melnikov, Ilarion V; Robbins, Daniel; Royston, Andrew B

    2015-01-01

    We calculate tree level scattering amplitudes for open strings using the NSR formalism. We present a streamlined symmetry-based and pedagogical approach to the computations, which we first develop by checking two-, three-, and four-point functions involving bosons and fermions. We calculate the five-point amplitude for massless gluons and find agreement with an earlier result by Brandt, Machado and Medina. We then compute the five-point amplitudes involving two and four fermions respectively, the general form of which has not been previously obtained in the NSR formalism. The results nicely confirm expectations from the supersymmetric $F^4$ effective action. Finally we use the prescription of Kawai, Lewellen and Tye (KLT) to compute the amplitudes for the closed string sector.

  16. Some tree-level string amplitudes in the NSR formalism

    Science.gov (United States)

    Becker, Katrin; Becker, Melanie; Melnikov, Ilarion V.; Robbins, Daniel; Royston, Andrew B.

    2015-12-01

    We calculate tree level scattering amplitudes for open strings using the NSR formalism. We present a streamlined symmetry-based and pedagogical approach to the computations, which we first develop by checking two-, three-, and four-point functions involving bosons and fermions. We calculate the five-point amplitude for massless gluons and find agreement with an earlier result by Brandt, Machado and Medina. We then compute the five-point amplitudes involving two and four fermions respectively, the general form of which has not been previously obtained in the NSR formalism. The results nicely confirm expectations from the supersymmetric F 4 effective action. Finally we use the prescription of Kawai, Lewellen and Tye (KLT) to compute the amplitudes for the closed string sector.

  17. Formalization of Database Systems -- and a Formal Definition of {IMS}

    DEFF Research Database (Denmark)

    Bjørner, Dines; Løvengreen, Hans Henrik

    1982-01-01

    Drawing upon an analogy between Programming Language Systems and Database Systems we outline the requirements that architectural specifications of database systems must futfitl, and argue that only formal, mathematical definitions may 6atisfy these. Then we illustrate home aspects and touch upon...... come ueee of formal definitions of data models and databaee management systems. A formal model of INS will carry this discussion. Finally we survey some of the exkting literature on formal definitions of database systems. The emphasis will be on constructive definitions in the denotationul semantics...

  18. Spinor formalism and complex-vector formalism of general relativity

    International Nuclear Information System (INIS)

    In this paper, using E. Cartan's exterior calculus, we give the spinor form of the structure equations, which leads naturally to the Newman--Penrose equations. Furthermore, starting from the spinor spaces and the el (2C) algebra, we construct the general complex-vector formalism of general relativity. We find that both the Cahen--Debever--Defrise complex-vector formalism and that of Brans are its special cases. Thus, the spinor formalism and the complex-vector formalism of general relativity are unified on the basis of the uni-modular group SL(2C) and its Lie algebra

  19. Boson-exchange nucleon-nucleon potential and nuclear structure

    International Nuclear Information System (INIS)

    A fully momentum-dependent one-boson-exchange potential is derived which takes into account the mesons, π, eta, sigma, rho, ω and phi. Scattering bound states and nuclear matter properties are studied in momentum space. The use of such potential is shown to be as easy as the use of more simple phenomenological interactions. In nuclear matter the formalism of Bethe-Goldstone is chosen to compute the binding energy versus density in the approximation of two-body and three-body correlations. The three-body correlated wave function obtained is then used

  20. Analytic boosted boson discrimination

    Science.gov (United States)

    Larkoski, Andrew J.; Moult, Ian; Neill, Duff

    2016-05-01

    Observables which discriminate boosted topologies from massive QCD jets are of great importance for the success of the jet substructure program at the Large Hadron Collider. Such observables, while both widely and successfully used, have been studied almost exclusively with Monte Carlo simulations. In this paper we present the first all-orders factorization theorem for a two-prong discriminant based on a jet shape variable, D 2, valid for both signal and background jets. Our factorization theorem simultaneously describes the production of both collinear and soft subjets, and we introduce a novel zero-bin procedure to correctly describe the transition region between these limits. By proving an all orders factorization theorem, we enable a systematically improvable description, and allow for precision comparisons between data, Monte Carlo, and first principles QCD calculations for jet substructure observables. Using our factorization theorem, we present numerical results for the discrimination of a boosted Z boson from massive QCD background jets. We compare our results with Monte Carlo predictions which allows for a detailed understanding of the extent to which these generators accurately describe the formation of two-prong QCD jets, and informs their usage in substructure analyses. Our calculation also provides considerable insight into the discrimination power and calculability of jet substructure observables in general.

  1. Twisted vertex algebras, bicharacter construction and boson-fermion correspondences

    International Nuclear Information System (INIS)

    The boson-fermion correspondences are an important phenomena on the intersection of several areas in mathematical physics: representation theory, vertex algebras and conformal field theory, integrable systems, number theory, cohomology. Two such correspondences are well known: the types A and B (and their super extensions). As a main result of this paper we present a new boson-fermion correspondence of type D-A. Further, we define a new concept of twisted vertex algebra of order N, which generalizes super vertex algebra. We develop the bicharacter construction which we use for constructing classes of examples of twisted vertex algebras, as well as for deriving formulas for the operator product expansions, analytic continuations, and normal ordered products. By using the underlying Hopf algebra structure we prove general bicharacter formulas for the vacuum expectation values for two important groups of examples. We show that the correspondences of types B, C, and D-A are isomorphisms of twisted vertex algebras

  2. Penrose limits versus string expansions

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Matthias; Weiss, Sebastian [Institut de Physique, Universite de Neuchatel, Rue Breguet 1, CH-2000 Neuchatel (Switzerland)

    2008-06-21

    We analyze the relation between two a priori quite different expansions of the string equations of motion and constraints in a general curved background, namely one based on the covariant Penrose-Fermi expansion of the metric G{sub {mu}}{sub {nu}} around a Penrose limit plane wave associated with a null geodesic {gamma} and the other on the Riemann coordinate expansion in the exact metric G{sub {mu}}{sub {nu}} of the string embedding variables around the null geodesic {gamma}. Starting with the observation that there is a formal analogy between the exact string equations in a plane wave and the first-order string equations in a general background, we show that this analogy becomes exact provided that one chooses the background string configuration to be the null geodesic {gamma} itself. We then explore the higher-order correspondence between these two expansions and find that for a general curved background they agree to all orders provided that one works in Fermi coordinates and in the lightcone gauge. Requiring moreover the conformal gauge restricts one to the usual class of (Brinkmann) backgrounds admitting simultaneously the lightcone and the conformal gauge, without further restrictions.

  3. Excited Weak Bosons and Dark Matter

    CERN Document Server

    Fritzsch, Harald

    2016-01-01

    The weak bosons are bound states of new constituents, the haplons. The p-wave excitations are studied. The state with the lowest mass is identified with the boson, which has been discovered at the LHC. Specific properties of the excited bosons are discussed, in particular their decays into weak bosons and photons. Recently a two photon signal has been observed, which might come from the decay of a neutral heavy boson with a mass of about 0.75 TeV. This particle could be the excited weak tensor boson. The stable fermion, consisting of three haplons, provides the dark matter in our universe.

  4. 40 years of formal methods

    DEFF Research Database (Denmark)

    Bjørner, Dines; Havelund, Klaus

    2014-01-01

    In this "40 years of formal methods" essay we shall first delineate, Sect. 1, what we mean by method, formal method, computer science, computing science, software engineering, and model-oriented and algebraic methods. Based on this, we shall characterize a spectrum from specification......-oriented methods to analysis-oriented methods. Then, Sect. 2, we shall provide a "survey": which are the 'prerequisite works' that have enabled formal methods, Sect. 2.1, and which are, to us, the, by now, classical 'formal methods', Sect. 2.2. We then ask ourselves the question: have formal methods for software...... development, in the sense of this paper been successful? Our answer is, regretfully, no! We motivate this answer, in Sect. 3.2, by discussing eight obstacles or hindrances to the proper integration of formal methods in university research and education as well as in industry practice. This "looking back" is...

  5. SDG fermion-pair algebraic SO(12) and Sp(10) models and their boson realizations

    CERN Document Server

    Navrátil, P; Dobes, J; Dobaczewski, J

    1994-01-01

    It is shown how the boson mapping formalism may be applied as a useful many-body tool to solve a fermion problem. This is done in the context of generalized Ginocchio models for which we introduce S-, D-, and G-pairs of fermions and subsequently construct the sdg-boson realizations of the generalized Dyson type. The constructed SO(12) and Sp(10) fermion models are solved beyond the explicit symmetry limits. Phase transitions to rotational structures are obtained, also in situations where there is no underlying SU(3) symmetry.

  6. SDG fermion-pair algebraic SO(12) and Sp(10) models and their boson realizations

    OpenAIRE

    Navratil, P.; Geyer, H. B.; Dobes, J.; Dobaczewski, J.

    1994-01-01

    It is shown how the boson mapping formalism may be applied as a useful many-body tool to solve a fermion problem. This is done in the context of generalized Ginocchio models for which we introduce S-, D-, and G-pairs of fermions and subsequently construct the sdg-boson realizations of the generalized Dyson type. The constructed SO(12) and Sp(10) fermion models are solved beyond the explicit symmetry limits. Phase transitions to rotational structures are obtained, also in situations where ther...

  7. U-boson at BESIII

    CERN Document Server

    Zhu, S

    2006-01-01

    The $O$(MeV) spin-1 U-boson has been proposed to mediate the interaction among electron-positron and $O$(MeV) dark matter, in order to account for the 511 keV $\\gamma$-ray observation by SPI/INTEGRAL. In this paper the observability of such kind of U-boson at BESIII is investigated through the processes $e^+e^- \\to U \\gamma$ and $e^+e^- \\to J/\\Psi \\to e^+e^- U$. We find that BESIII and high luminosity B-factories have the comparable capacity to detect such U-boson. If U-boson decays mainly into dark matter, i.e. invisibly, BESIII can measure the coupling among U-boson and electron-positron $g_{eR}$ (see text) down to $O(10^{-5})$, and cover large parameter space which can account for 511 keV $\\gamma$-ray observation. On the other hand, provided that U decays mainly into electron-positron, BESIII can detect $g_{eR}$ down to $O(10^{-3})$, and it is hard to explore 511 keV $\\gamma$-ray measurement allowed parameter space due to the irreducible QED backgrounds.

  8. Spin models and boson sampling

    Science.gov (United States)

    Garcia Ripoll, Juan Jose; Peropadre, Borja; Aspuru-Guzik, Alan

    Aaronson & Arkhipov showed that predicting the measurement statistics of random linear optics circuits (i.e. boson sampling) is a classically hard problem for highly non-classical input states. A typical boson-sampling circuit requires N single photon emitters and M photodetectors, and it is a natural idea to rely on few-level systems for both tasks. Indeed, we show that 2M two-level emitters at the input and output ports of a general M-port interferometer interact via an XY-model with collective dissipation and a large number of dark states that could be used for quantum information storage. More important is the fact that, when we neglect dissipation, the resulting long-range XY spin-spin interaction is equivalent to boson sampling under the same conditions that make boson sampling efficient. This allows efficient implementations of boson sampling using quantum simulators & quantum computers. We acknowledge support from Spanish Mineco Project FIS2012-33022, CAM Research Network QUITEMAD+ and EU FP7 FET-Open Project PROMISCE.

  9. A Z' Boson and the Higgs Boson Mass

    OpenAIRE

    Chanowitz, Michael S.

    2008-01-01

    The Standard Model fit prefers values of the Higgs boson mass that are below the 114 GeV direct lower limit from LEP II. The discrepancy is acute if the 3.2 sigma disagreement for the effective weak interaction mixing angle from the two most precise measurements is attributed to underestimated systematic error. In that case the data suggests new physics to raise the predicted value of the Higgs mass. One of the simplest possibilities is a Z' boson, which would generically increase the predict...

  10. Quantum field theory of dilute homogeneous Bose-Fermi mixtures at zero temperature: General formalism and beyond mean-field corrections

    International Nuclear Information System (INIS)

    We consider a dilute homogeneous mixture of bosons and spin-polarized fermions at zero temperature. We first construct the formal scheme for carrying out systematic perturbation theory in terms of single particle Green's functions. We especially focus on the description of the boson-fermion interaction. To do so we need to introduce the renormalized boson-fermion T matrix, which we determine to second order in the boson-fermion s-wave scattering length. We also discuss how to incorporate the usual boson-boson T matrix in mean field approximation to obtain the total ground-state properties of the system. The next-order term beyond mean field stems from the boson-fermion interaction and is proportional to aBFkF. The total ground-state energy density to this order is the sum of the kinetic energy of the free fermions, the boson-boson mean-field interaction, the usual mean-field contribution to the boson-fermion interaction energy, and the first boson-fermion correction beyond mean field. We also compute the bosonic and the fermionic chemical potentials, the compressibilities, and the modification to the induced fermion-fermion interaction. We discuss the behavior of the total ground-state energy and the importance of the correction beyond mean field for various parameter regimes, in particular considering mixtures of 6Li and 7Li and of 3He and 4He. Moreover, we determine the modification of the induced fermion-fermion interaction due to the effects beyond mean field. We show that there is no effect on the depletion of the Bose condensate to first order in the boson-fermion scattering length aBF

  11. Inclusion of g boson in the microscopic sdgIBM and the g boson effect

    International Nuclear Information System (INIS)

    The inclusion of g boson in the microscopic sdgIBM is presented. The collectivity of g boson, the relationship between g boson properties and the strengths of the effective nucleon-nucleon interaction, and the influence of g boson on the sdIBM are discussed in detail

  12. Medium-induced gluon radiation in hard forward parton scattering in the saturation formalism

    CERN Document Server

    Munier, Stéphane; Petreska, Elena

    2016-01-01

    We derive the medium-induced, coherent gluon radiation spectrum associated with the hard forward scattering of an energetic parton off a nucleus, in the saturation formalism and within the Gaussian approximation for the relevant correlators of Wilson lines. The calculation reproduces the simple expression for the spectrum previously obtained in the opacity expansion formalism, and rigorously specifies its validity range. The connection between the calculations in the opacity expansion and saturation formalisms is made apparent. This study may serve as a first step in order to implement consistently induced coherent energy loss and gluon shadowing in `saturation-based models' of hadron nuclear suppression in proton-nucleus collisions.

  13. Light Front Boson Model Propagation

    Institute of Scientific and Technical Information of China (English)

    Jorge Henrique Sales; Alfredo Takashi Suzuki

    2011-01-01

    stract The scope and aim of this work is to describe the two-body interaction mediated by a particle (either the scalar or the gauge boson) within the light-front formulation. To do this, first of all we point out the importance of propagators and Green functions in Quantum Mechanics. Then we project the covariant quantum propagator onto the light front time to get the propagator for scalar particles in these coordinates. This operator propagates the wave function from x+ = 0 to x+ > O. It corresponds to the definition of the time ordering operation in the light front time x+. We calculate the light-front Green's function for 2 interacting bosons propagating forward in x+. We also show how to write down the light front Green's function from the Feynman propagator and finally make a generalization to N bosons.

  14. Gauss–Bonnet boson stars

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Betti, E-mail: b.hartmann@jacobs-university.de [School of Engineering and Science, Jacobs University Bremen, 28759 Bremen (Germany); Riedel, Jürgen, E-mail: j.riedel@jacobs-university.de [School of Engineering and Science, Jacobs University Bremen, 28759 Bremen (Germany); Faculty of Physics, University Oldenburg, 26111 Oldenburg (Germany); Suciu, Raluca, E-mail: r.suciu@jacobs-university.de [School of Engineering and Science, Jacobs University Bremen, 28759 Bremen (Germany)

    2013-11-04

    We construct boson stars in (4+1)-dimensional Gauss–Bonnet gravity. We study the properties of the solutions in dependence on the coupling constants and investigate in detail their properties. While the “thick wall” limit is independent of the value of the Gauss–Bonnet coupling, we find that the spiraling behaviour characteristic for boson stars in standard Einstein gravity disappears for large enough values of the Gauss–Bonnet coupling. Our results show that in this case the scalar field can not have arbitrarily high values of the scalar field at the center of the boson star and that it is hence impossible to reach the “thin wall” limit. Moreover, for large enough Gauss–Bonnet coupling we find a unique relation between the mass and the radius (qualitatively similar to those of neutron stars) which is not present in the Einstein gravity limit.

  15. A Formalization of Linkage Analysis

    DEFF Research Database (Denmark)

    Ingolfsdottir, Anna; Christensen, A.I.; Hansen, Jens A.;

    In this report a formalization of genetic linkage analysis is introduced. Linkage analysis is a computationally hard biomathematical method, which purpose is to locate genes on the human genome. It is rooted in the new area of bioinformatics and no formalization of the method has previously been ...

  16. Formal Verification of UML Profil

    DEFF Research Database (Denmark)

    Bhutto, Arifa; Hussain, Dil Muhammad Akbar

    2011-01-01

    and object diagrams and behavioral view model by the activity, use case, state, and sequence diagram. However, UML does not provide the formal syntax, therefore its semantics is not formally definable, so for assure of correctness, we need to incorporate semantic reasoning through verification...

  17. Higgs boson production at the LHC

    CERN Document Server

    Peters, Krisztian; The ATLAS collaboration

    2015-01-01

    After the discovery at the LHC, the main goal of the Higgs boson measurements at ATLAS and CMS is to fully elucidate the nature of this new particle. In this contribution we will discuss the Higgs boson production and decay properties at the LHC and the main analyses which build the fundation for the current Higgs boson property measurements. Inclusive rates as well as differential measurements in the main bosonic and fermionic channels, and searches for rarer decay modes will be presented.

  18. Bosonic Coherent Motions in the Universe

    CERN Document Server

    Kim, Jihn E; Tsujikawa, Shinji

    2014-01-01

    We mini-review the role of fundamental spin-0 bosons as bosonic coherent motion (BCM) in the Universe. The fundamental spin-0 bosons have the potential to account for the baryon number generation, cold dark matter (CDM) via BCM, dark energy, and inflation. Among these, here we focus on the CDM possibility because it can be experimentally tested with the current experimental techniques. We also comment briefly on the panoply of the other roles of spin-0 bosons.

  19. New procedure for departure formalities

    CERN Multimedia

    HR & GS Departments

    2011-01-01

    As part of the process of simplifying procedures and rationalising administrative processes, the HR and GS Departments have introduced new personalised departure formalities on EDH. These new formalities have applied to students leaving CERN since last year and from 17 October 2011 this procedure will be extended to the following categories of CERN personnel: Staff members, Fellows and Associates. It is planned to extend this electronic procedure to the users in due course. What purpose do departure formalities serve? The departure formalities are designed to ensure that members of the personnel contact all the relevant services in order to return any necessary items (equipment, cards, keys, dosimeter, electronic equipment, books, etc.) and are aware of all the benefits to which they are entitled on termination of their contract. The new departure formalities on EDH have the advantage of tailoring the list of services that each member of the personnel must visit to suit his individual contractual and p...

  20. Formal connections in deformation quantization

    DEFF Research Database (Denmark)

    Masulli, Paolo

    manifold. Gammelgaard gave an explicit formula for a class of star products in this setting. We review his construction, which is combinatorial and based on a certain family of graphs and extend it, to provide the graph formalism with the notions of composition and differentiation. We shall focus our...... attention on symplectic manifolds equipped with a family of star products, indexed by a parameter space. In this situation we can define a connection in the trivial bundle over the parameter space with fibres the formal smooth functions on the manifold, which relates the star products in the family and is...... called a formal connection. We study the question of classifying such formal connections. To each star product we can associate a certain cohomology class called the characteristic class. It turns out that a formal connection exists if and only if all the star products in the family have the same...

  1. Vectorial versus axial goldstone bosons

    International Nuclear Information System (INIS)

    The Yukawa interactions of fermions with Goldstone bosons are given in closed form for an arbitrary renormalizable field theory to all orders of perturbation theory or for a general effective Lagrangian. Although the diagonal couplings are always pseudoscalar there is an important difference between spontaneously broken vector and axial-vector global symmetries. Compared to the axial case, the diagonal douplings of 'vectorial' Goldstone bosons to charged fermions are suppressed by mixing angles or appear only via radiative corrections involving gauge fields. This general result may be relevant for the problem of flavour symmetry breaking in composite models. (Author)

  2. Boson stars in the centre of galaxies?

    CERN Document Server

    Schunck, Franz E

    2008-01-01

    We investigate the possible gravitational redshift values for boson stars with a self-interaction, studying a wide range of possible masses. We find a limiting value of z_lim \\simeq 0.687 for stable boson star configurations. We can exclude the direct observation of boson stars. X-ray spectroscopy is perhaps the most interesting possibility.

  3. A generalization of boson normal ordering

    International Nuclear Information System (INIS)

    In this Letter we define generalizations of boson normal ordering. These are based on the number of contractions whose vertices are next to each other in the linear representation of the boson operator function. Our main motivation is to shed further light onto the combinatorics arising from algebraic and Fock space properties of boson operators

  4. Introduction to the physics of Higgs bosons

    Energy Technology Data Exchange (ETDEWEB)

    Dawson, S.

    1994-11-01

    A basic introduction to the physics of the Standard Model Higgs boson is given. We discuss Higgs boson production in e{sup +}e{sup {minus}} and hadronic collisions and survey search techniques at future accelerators. The Higgs bosons of the minimal SUSY model are briefly considered. Indirect limits from triviality arguments, vacuum stability and precision measurements at LEP are also presented.

  5. Charged Higgs Bosons in the LHCHXSWG

    CERN Document Server

    Heinemeyer, S

    2014-01-01

    Searches for charged Higgs bosons are an integral part of current and future investigations at the LHC. The LHC Higgs Cross Section Working Group (LHCHXSWG) was created to provide cross sections, branching ratios, analysis strategies etc. for Higgs boson searches at the LHC. We briefly review progress and results for charged Higgs bosons in and for the LHCHXSWG.

  6. Introduction to the physics of Higgs bosons

    International Nuclear Information System (INIS)

    A basic introduction to the physics of the Standard Model Higgs boson is given. We discuss Higgs boson production in e+e- and hadronic collisions and survey search techniques at future accelerators. The Higgs bosons of the minimal SUSY model are briefly considered. Indirect limits from triviality arguments, vacuum stability and precision measurements at LEP are also presented

  7. Twisted bosonization in two dimensional noncommutative spacetime

    CERN Document Server

    Haque, Asrarul

    2012-01-01

    We study the twisted bosonization of massive Thirring model to relate to sine-Gordon model in Moyal spacetime using twisted commutation relations. We obtain the relevant twisted bosonization rules. We show that there exists dual rela- tionship between twisted bosonic and fermionic operators. The strong-weak duality is also observed to be preserved as its commutative counterpart.

  8. Exploring the spectrum of regularized bosonic string theory

    International Nuclear Information System (INIS)

    We implement a UV regularization of the bosonic string by truncating its mode expansion and keeping the regularized theory “as diffeomorphism invariant as possible.” We compute the regularized determinant of the 2d Laplacian for the closed string winding around a compact dimension, obtaining the effective action in this way. The minimization of the effective action reliably determines the energy of the string ground state for a long string and/or for a large number of space-time dimensions. We discuss the possibility of a scaling limit when the cutoff is taken to infinity

  9. Three-boson bound states in finite volume with EFT

    International Nuclear Information System (INIS)

    The universal properties of a three-boson system with large scattering length are well understood within the framework of Effective Field Theory. They include a geometric spectrum of shallow three-body bound states called Efimov states and log-periodic dependence of scattering observables on the scattering length. We investigate the modification of this spectrum in a finite cubic box using a partial wave expansion. The dependence of the binding energies on the box size is calculated and the renormalization of the Effective Field Theory in finite volume is verified explicitly.

  10. Evidence of Higgs Boson Production through Vector Boson Fusion

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00333580

    The discovery of the Higgs boson in 2012 provided confirmation of the proposed mechanism for preserving the electroweak $SU(2) \\times U(1)$ gauge symmetry of the Standard Model of particle physics. It also heralded in a new era of precision Higgs physics. This thesis presents a measurement of the rate at which the Higgs boson is produced by vector boson fusion in the \\wwlnln decay channel. With gauge boson couplings in both the production and decay vertices, a VBF measurement in this channel is a powerful probe of the $VVH$ vertex strength. Using $4.5$~fb$^{-1}$ and $20.3$~fb$^{-1}$ of $pp$ collision data collected at respective center-of-mass energies of 7 and $8 \\tev$ in the ATLAS detector, measurements of the statistical significance and the signal strength are carried out in the Higgs mass range $100 \\leq m_H \\leq 200 \\gev$. These measurements are enhanced with a boosted decision tree that exploits the correlations between eight kinematic inputs in order to separate signal and background processes. At the...

  11. Diffeomorphisms as symplectomorphisms in history phase space: Bosonic string model

    International Nuclear Information System (INIS)

    The structure of the history phase space G of a covariant field system and its history group (in the sense of Isham and Linden) is analyzed on an example of a bosonic string. The history space G includes the time map T from the spacetime manifold (the two-sheet) Y to a one-dimensional time manifold T as one of its configuration variables. A canonical history action is posited on G such that its restriction to the configuration history space yields the familiar Polyakov action. The standard Dirac-ADM action is shown to be identical with the canonical history action, the only difference being that the underlying action is expressed in two different coordinate charts on G. The canonical history action encompasses all individual Dirac-ADM actions corresponding to different choices T of foliating Y. The history Poisson brackets of spacetime fields on G induce the ordinary Poisson brackets of spatial fields in the instantaneous phase space G0 of the Dirac-ADM formalism. The canonical history action is manifestly invariant both under spacetime diffeomorphisms Diff Y and temporal diffeomorphisms Diff T. Both of these diffeomorphisms are explicitly represented by symplectomorphisms on the history phase space G. The resulting classical history phase space formalism is offered as a starting point for projection operator quantization and consistent histories interpretation of the bosonic string model

  12. Matrix models as CFT: Genus expansion

    International Nuclear Information System (INIS)

    We show how the formulation of the matrix models as conformal field theories on a Riemann surfaces can be used to compute the genus expansion of the observables. Here we consider the simplest example of the Hermitian matrix model, where the classical solution is described by a hyperelliptic Riemann surface. To each branch point of the Riemann surface we associate an operator which represents a twist field dressed by the modes of the twisted boson. The partition function of the matrix model is computed as a correlation function of such dressed twist fields. The perturbative construction of the dressing operators yields a set of Feynman rules for the genus expansion, which involve vertices, propagators and tadpoles. The vertices are universal, the propagators and the tadpoles depend on the Riemann surface. As a demonstration we evaluate the genus-two free energy using the Feynman rules.

  13. Formal verification - Robust and efficient code: Introduction to Formal Verification

    CERN Document Server

    CERN. Geneva

    2016-01-01

    In general, FV means "proving that certain properties hold for a given system using formal mathematics". This definition can certainly feel daunting, however, as we will learn, we can reap benefits from the paradigm without digging too deep into ...

  14. Composite gauge-bosons made of fermions

    CERN Document Server

    Suzuki, Mahiko

    2016-01-01

    We construct a class of Abelian and non-Abelian local gauge theories that consist only of matter fields of fermions. The Lagrangian is compact and local without containing an auxiliary vector field nor a subsidiary condition on the matter fields. Because of the special structure, this Lagrangian can be extended to non-Abelian gauge symmetry only in the case of SU(2) doublet matter fields. We carry out explicit dynamical computation in the leading 1/N order to show that massless spin-one bound states appear with the correct gauge coupling. Our diagram calculation exposes the dynamical features that cannot be explored in the formal auxiliary vector-field trick. For instance, it shows that the s-wave fermion-antifermion interaction alone cannot form the bound gauge-bosons; the fermion-antifermion pairs must couple to the d-wave state too. Since our models are unrenormalizable in the world of (3+1) dimension, they can be phenomenologically relevant, if at all, only when momentum cutoff is introduced.

  15. Scalable Techniques for Formal Verification

    CERN Document Server

    Ray, Sandip

    2010-01-01

    This book presents state-of-the-art approaches to formal verification techniques to seamlessly integrate different formal verification methods within a single logical foundation. It should benefit researchers and practitioners looking to get a broad overview of the spectrum of formal verification techniques, as well as approaches to combining such techniques within a single framework. Coverage includes a range of case studies showing how such combination is fruitful in developing a scalable verification methodology for industrial designs. This book outlines both theoretical and practical issue

  16. Formal Component-Based Semantics

    CERN Document Server

    Madlener, Ken; van Eekelen, Marko; 10.4204/EPTCS.62.2

    2011-01-01

    One of the proposed solutions for improving the scalability of semantics of programming languages is Component-Based Semantics, introduced by Peter D. Mosses. It is expected that this framework can also be used effectively for modular meta theoretic reasoning. This paper presents a formalization of Component-Based Semantics in the theorem prover Coq. It is based on Modular SOS, a variant of SOS, and makes essential use of dependent types, while profiting from type classes. This formalization constitutes a contribution towards modular meta theoretic formalizations in theorem provers. As a small example, a modular proof of determinism of a mini-language is developed.

  17. Formal Methods: Practice and Experience

    DEFF Research Database (Denmark)

    Woodcock, Jim; Larsen, Peter Gorm; Bicarregui, Juan;

    2009-01-01

    Formal methods use mathematical models for analysis and verification at any part of the program life-cycle. We describe the state of the art in the industrial use of formal methods, concentrating on their increasing use at the earlier stages of specification and design. We do this by reporting on a....... Based on this, we discuss the issues surrounding the industrial adoption of formal methods. Finally, we look to the future and describe the development of a Verified Software Repository, part of the worldwide Verified Software Initiative. We introduce the initial projects being used to populate the...

  18. Bosonic interactions with a domain wall

    CERN Document Server

    Morris, J R

    2016-01-01

    We consider here the interaction of scalar bosons with a topological domain wall. Not only is there a continuum of scattering states, but there is also an interesting "quasi-discretuum" of positive energy bosonic bound states, describing bosons entrapped within the wall's core. The full spectrum of the scattering and bound state energies and eigenstates is obtainable from a Schr\\"odinger-type of equation with a P\\"oschl-Teller potential. We also consider the presence of a boson gas within the wall and high energy boson emission.

  19. Excited Weak Bosons and Dark Matter

    OpenAIRE

    Fritzsch, Harald

    2016-01-01

    The weak bosons are bound states of new constituents, the haplons. The p-wave excitations are studied. The state with the lowest mass is identified with the boson, which has been discovered at the LHC. Specific properties of the excited bosons are discussed, in particular their decays into weak bosons and photons. Recently a two photon signal has been observed, which might come from the decay of a neutral heavy boson with a mass of about 0.75 TeV. This particle could be the excited weak tenso...

  20. A geometrical representation of the interacting-boson model of nuclei

    International Nuclear Information System (INIS)

    The representation of the interacting-boson-model Hamiltonian as a second-order differential operator in geometrical variables is studied in detail. It is shown that, with appropriate boundary conditions and biorthogonal weight functions, it reproduces exactly both the spectrum and matrix elements of operators of the algebraic boson model. It can be written in self-adjoint form and expanded in a symmetrized moment expansion, allowing the identification of collective mass parameters and energy surfaces, but differs in detail from conventional geometrical collective model. (author)

  1. Completeness of spin-3 field in two-boson free-field-realized conformal field theory

    International Nuclear Information System (INIS)

    We consider the higher- (integer-)spin fields which can be realized with the derivatives of two-boson free fields in two-dimensional conformal quantum field theory. We show that the operator-product expansion (OPE) between higher-spin fields themselves cannot be closed when the spins are larger than 3. Thus, with the requirement of the closure of the OPE, the spin-3 field given by Fateev and Zamolodchikov is uniquely possible---that is, it is ''complete.'' The same analyses on N- (≥3-) boson free-field-realized conformal field theories are discussed

  2. Gravitational Stability of Boson Stars

    CERN Document Server

    Kusmartsev, Fjodor V; Schunck, Franz E

    1991-01-01

    We investigate the stability of general-relativistic boson stars by classifying singularities of differential mappings and compare it with the results of perturbation theory. Depending on the particle number, the star has the following regimes of behavior: stable, metastable, pulsation, and collapse.

  3. How to Detect `Decoupled' Heavy Supersymmetric Higgs Bosons

    CERN Document Server

    Bisset, Mike; Li, Jun

    2007-01-01

    Heretofore neglected decay modes of heavy MSSM Higgs bosons into a variety of neutralino pairs may push the LHC discovery reach for these crucial elements of an extended Higgs sector to nearly the TeV-scale -- if sparticle-sector MSSM input parameters are favorable. This is well into the so-called decoupling region, including moderate to low tan(beta) values, where no known signals exist for said heavy Higgs bosons via decays involving solely SM daughter particles, and the lighter h^0 mimics the lone SM Higgs boson. While the expanse of the Higgs to sparticle discovery region is sensitive to a number of MSSM parameters, including in particular those for the sleptons, its presence is primarily linked to the gaugino inputs -- in fact, to just one parameter, M_2, if gaugino unification is invoked. Thus consideration of high vs. low M_2 realms in the MSSM should be placed on a par with the extensive consideration already given to high vs. low tan(beta) regimes.

  4. Formal and informal contract farming in poultry in Bangladesh

    OpenAIRE

    Jabbar, Mohammad A.; Rahman, Md. Habibur; Talukder, R. K.; Raha, S.K.

    2008-01-01

    Since the early 1990s, contract farming as a market institution in the poultry industry in Bangladesh has evolved along with the expansion of commercial poultry farming. Apart from classical contract farming within vertically integrated enterprises, there are also formal and informal contract arrangements in input marketing and output marketing. In this paper, characteristics of these forms of contract arrangements and their implications for the poultry industry in Bangladesh are discussed. A...

  5. Locally-smeared operator product expansions

    CERN Document Server

    Monahan, Christopher

    2014-01-01

    We propose a "locally-smeared Operator Product Expansion" (sOPE) to decompose non-local operators in terms of a basis of locally-smeared operators. The sOPE formally connects nonperturbative matrix elements of smeared degrees of freedom, determined numerically using the gradient flow, to non-local operators in the continuum. The nonperturbative matrix elements do not suffer from power-divergent mixing on the lattice, provided the smearing scale is kept fixed in the continuum limit. The presence of this smearing scale prevents a simple connection to the standard operator product expansion and therefore requires the construction of a two-scale formalism. We demonstrate the feasibility of our approach using the example of real scalar field theory.

  6. Inclusive production of Higgs boson in the two-photon channel at the LHC within $k_{t}$-factorization approach and with the Standard Model couplings

    OpenAIRE

    Szczurek, Antoni(Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, PL-31-342, Kraków, Poland); Luszczak, Marta; Maciula, Rafal

    2014-01-01

    We calculate differential cross sections for Higgs boson and/or two-photon production from intermediate (virtual) Higgs boson within the formalism of $k_t$-factorization. The off-shell $g^* g^* \\to H$ matrix elements are used. We compare results obtained with infinite top fermion (quark) mass and with finite mass taken into account. The latter effect is rather small. We compare results with different unintegrated gluon distributions from the literature. Two methods are used. In the first meth...

  7. El Salvador - Formal Technical Education

    Data.gov (United States)

    Millenium Challenge Corporation — With a budget of nearly $20 million, the Formal Technical Education Sub-Activity was designed to strengthen technical and vocational educational institutions in the...

  8. The sensitivity of the Higgs boson branching ratios to the W boson width

    Science.gov (United States)

    Murray, William

    2016-07-01

    The Higgs boson branching ratio into vector bosons is sensitive to the decay widths of those vector bosons because they are produced with at least one boson significantly off-shell. Γ (H → VV) is approximately proportional to the product of the Higgs boson coupling and the vector boson width. ΓZ is well measured, but ΓW gives an uncertainty on Γ (H → WW) which is not negligible. The ratio of branching ratios, BR (H → WW) / BR (H → ZZ) measured by a combination of ATLAS and CMS at LHC is used herein to extract a width for the W boson of ΓW =1.8-0.3+0.4 GeV by assuming Standard Model couplings of the Higgs bosons. This dependence of the branching ratio on ΓW is not discussed in most Higgs boson coupling analyses.

  9. The sensitivity of the Higgs boson branching ratios to the W boson width

    CERN Document Server

    Murray, William

    2016-01-01

    The Higgs boson branching ratio into vector bosons is sensitive to the decay widths of those vector bosons because they are produced with at least one boson significantly off-shell. Gamma(H to V V ) is approximately proportional to the product of the Higgs boson coupling and the vector boson width. Gamma Z is well known, but Gamma W gives an uncertainty on Gamma(H to W W ) which is not negligible. The ratio of branching ratios, BR(H to W W )/BR(H to ZZ) measured by a combination of ATLAS and CMS at LHC is used herein to extract a width for the W boson of Gamma W = 1.8+0.4-0.3 GeV by assuming Standard Model couplings of the Higgs bosons. This dependence of the branching ratio on Gamma W is not discussed in most Higgs boson coupling analyses.

  10. Helicity formalism and spin effects

    International Nuclear Information System (INIS)

    The helicity formalism and the technique to compute amplitudes for interaction processes involving leptons, quarks, photons and gluons are reviewed. Explicit calculations and examples of exploitation of symmetry properties are shown. The formalism is then applied to the discussion of several hadronic processes and spin effects: the experimental data, when related to the properties of the elementary constituent interactions, show many not understood features. Also the nucleon spin problem is briefly reviewed. (author)

  11. Complex cobordism and formal groups

    Science.gov (United States)

    Buchstaber, Viktor M.

    2012-10-01

    This paper surveys the current state of the theory of cobordism, focusing on geometric and universal properties of complex cobordism, the Landweber-Novikov algebra, and the formal group law of geometric cobordisms. The relationships with K-theory, algebraic cycles, formal group laws, compact Lie group actions on manifolds, toric topology, infinite-dimensional Lie algebras, and nilmanifolds are described. The survey contains key results and open problems. Bibliography: 124 titles.

  12. Beam expansion with specified final distributions

    International Nuclear Information System (INIS)

    The formation of nearly uniformly distributed beams has been accomplished by the use of multipole magnets. Multipole fields, however, are an inappropriate basis for creating precise distributions, particularly since substantial departures from uniformity are produced with a finite number of multipole elements. A more appropriate formalism that allows precise formation of a desired distribution is presented. Design of nonlinear magnets for uniform-beam production and the optics of an accompanying expansion system are presented

  13. Topological Properties of Rough Soft Formal Context

    OpenAIRE

    Li Fu

    2014-01-01

    In this paper, the topological structure is discussed in the rough soft formal context. The rough soft formal context is defined on the rough formal context with some soft operators, the topology and the topological space are given in the rough soft formal context. And some topological properties are discussed over the rough soft formal context.

  14. Generalized boson model

    International Nuclear Information System (INIS)

    In the paper it is noted, that it is necessary to develop dynamical symmetries as U(6) direct X U(4) which take into account a quadrupole nuclear collectivization, a dipole quasi-molecular clusterization as well as an interaction of quadrupole and dipole degrees of freedom. The group chains U(6) direct X U(4) contains SUd(3) direct X Up(3) contains 0(3); U(6) direct X U(4) contains SUd(3) direct X SUp(3) contains 0(3) are investigated. In te both chains the quadrupole collective motion of nucleons generates in an energetic spectrum band of rotational character, classified by representations of (λ, μ), following from the expansion: U(6) contains SU(3). In the lowest order there are (2N, 0), (2N-4.2), k=0+,2+, etc. From group reduction for U(4), taking into account the cluster from of the motion by the model of dipole clusterization of atomic nucleus nucleons, two variant of a theory were developed: a vibration limit of U(4) contains U(3) O(3) and a rotational limit of U(4) contains SU(3) contains O(3). In spite of an apparent identity of groups of U(3) and SU(3) variants of the model generate different spectra of cluster states of atomic nuclei. For the vibration limit the theory predicts an alteration of cluster states of even and odd parities 0+, 1-, 2+, 3-, for the rotational limit there is taken place some electrogenic shift between bands of levels of even and odd parities. The first type of excitations is observed for such nuclei as 28Si, :32S, 36Ar, 44Ti te second type of excitation is observed for light nuclei, such as 16O and 20Ne. An interaction of collective quadrupole and cluster degrees of freedom is taken into account by approximate methods

  15. Prospects for the search for Higgs bosons with vector boson fusion processes at the LHC

    OpenAIRE

    Rottlaender, Iris

    2007-01-01

    The search for the Higgs boson is one of the main physics goals of the Large Hadron Collider (LHC) and its two multi-purpose experiments, ATLAS and CMS. Vector boson fusion is the second largest production process for a standard model Higgs boson at the LHC and offers excellent means for background suppression. This paper gives an overview of the prospects of Higgs boson searches using vector boson fusion at the LHC. For a standard model Higgs boson, the decay channels H->tautau, H->WW and H-...

  16. Supersymmetry and compositeness; dynamical weak gauge bosons

    International Nuclear Information System (INIS)

    We show at the leading order of 1/N expansion that composite gauge fields in a supersymmetric U(4n + 2)/U(4n) x SU(2) non-linear sigma model become dynamical in some range of parameters. Since the hidden local symmetry in this sigma model is identifiable with a weak SU(2) of the standard electroweak model, we suggest that the observed weak bosons W+- and Z0 are indeed the dynamical gauge fields in the non-linear sigma model. Some phenomenological difficulies in identifing such composite fields with W+- and Z0 are discussed. We also give a brief review on a supersymmetric preon model which generates our non-linear sigma model as a low-energy effective theory. I. Introduction. In spite of the excellent success of the standard electroweak gauge theory [1], it is still unclear to us what the origin of the spontaneous breakdown of the SU(2) x U(1) symmetry is. In the standard scheme, an elementary Higgs scalar phi is assumed to have a vacuum-expectation value not equal 0 which induces the breaking of the electroweak symmetry. The Fermi scale G sub(F)sup(-1/2) is thus related basically to the undetermined, free parameter, . (author)

  17. Reconstruction of the Higgs mass in events with Higgs bosons decaying into a pair of tau leptons using matrix element techniques

    CERN Document Server

    Bianchini, L; Conway, J; Fowlie, A; Marzola, L; Veelken, C

    2016-01-01

    We present an algorithm for the reconstruction of the Higgs mass in events with Higgs bosons decaying into a pair of tau leptons. The algorithm is based on matrix element (ME) techniques and achieves a relative resolution on the Higgs boson mass of typically 15-20%. A previous version of the algorithm has been used in analyses of Higgs boson production performed by the CMS collaboration during LHC Run 1. The algorithm is described in detail and its performance on simulated events is assessed. The development of techniques to handle tau decays in the ME formalism represents an important result of this paper.

  18. Unified Equations of Boson and Fermion at High Energy and Some Unifications in Particle Physics

    OpenAIRE

    Chang, Yi-Fang

    2009-01-01

    We suggest some possible approaches of the unified equations of boson and fermion, which correspond to the unified statistics at high energy. A. The spin terms of equations can be neglected. B. The mass terms of equations can be neglected. C. The known equations of formal unification change to the same. They can be combined each other. We derive the chaos solution of the nonlinear equation, in which the chaos point should be a unified scale. Moreover, various unifications in particle physics ...

  19. A short introduction to the quantum formalism[s

    CERN Document Server

    David, Francois

    2012-01-01

    These notes are an elaboration on: (i) a short course that I gave at the IPhT-Saclay in May-June 2012; (ii) a previous letter on reversibility in quantum mechanics. They present an introductory, but hopefully coherent, view of the main formalizations of quantum mechanics, of their interrelations and of their common physical underpinnings: causality, reversibility and locality/separability. The approaches covered are mainly: (ii) the canonical formalism; (ii) the algebraic formalism; (iii) the quantum logic formulation. Other subjects: quantum information approaches, quantum correlations, contextuality and non-locality issues, quantum measurements, interpretations and alternate theories, quantum gravity, are only very briefly and superficially discussed. Most of the material is not new, but is presented in an original, homogeneous and hopefully not technical or abstract way. I try to define simply all the mathematical concepts used and to justify them physically. These notes should be accessible to young physi...

  20. Scattering length of composite bosons in the three-dimensional BCS-BEC crossover

    Science.gov (United States)

    Salasnich, L.; Bighin, G.

    2015-03-01

    We study the zero-temperature grand potential of a three-dimensional superfluid made of ultracold fermionic alkali-metal atoms in the BCS-BEC crossover. In particular, we analyze the zero-point energy of both fermionic single-particle excitations and bosonic collective excitations. The bosonic elementary excitations, which are crucial to obtain a reliable equation of state in the Bose-Einstein condensate regime, are obtained with a low-momentum expansion up to the forth order of the quadratic (Gaussian) action of the fluctuating pairing field. By performing a cutoff regularization and renormalization of Gaussian fluctuations, we find that the scattering length aB of composite bosons, bound states of fermionic pairs, is given by aB=(2 /3 ) aF , where aF is the scattering length of fermions.

  1. One or more Higgs bosons?

    CERN Document Server

    Barbieri, Riccardo; Kannike, Kristjan; Sala, Filippo; Tesi, Andrea

    2013-01-01

    Now that one has been found, the search for signs of more scalars is a primary task of current and future experiments. In the motivated hypothesis that the extra Higgs bosons of the next-to-minimal supersymmetric Standard Model (NMSSM) be the lightest new particles around, we outline a possible overall strategy to search for signs of the CP-even states. This work complements Ref. arXiv:1304.3670.

  2. The Higgs boson is unveiled

    International Nuclear Information System (INIS)

    The 4 of July 2012, the CERN physicists announced the discovery of the Higgs boson, a particle which existence is essential to the understanding of our world. The paper relates this day which will remain in the history of the physics of particles, and gives some details of the results of the CMS and Atlas experiments on the CERN Large Hadron Collider (LHC). Results from the Fermilab's Tevatron accelerator are also mentioned

  3. Bosonic colored group field theory

    Energy Technology Data Exchange (ETDEWEB)

    Ben Geloun, Joseph [Universite Paris XI, Laboratoire de Physique Theorique, Orsay Cedex (France); University of Abomey-Calavi, Cotonou (BJ). International Chair in Mathematical Physics and Applications (ICMPA-UNESCO Chair); Universite Cheikh Anta Diop, Departement de Mathematiques et Informatique, Faculte des Sciences et Techniques, Dakar (Senegal); Magnen, Jacques [Ecole Polytechnique, Centre de Physique Theorique, Palaiseau Cedex (France); Rivasseau, Vincent [Universite Paris XI, Laboratoire de Physique Theorique, Orsay Cedex (France)

    2010-12-15

    Bosonic colored group field theory is considered. Focusing first on dimension four, namely the colored Ooguri group field model, the main properties of Feynman graphs are studied. This leads to a theorem on optimal perturbative bounds of Feynman amplitudes in the ''ultraspin'' (large spin) limit. The results are generalized in any dimension. Finally, integrating out two colors we write a new representation, which could be useful for the constructive analysis of this type of models. (orig.)

  4. Electroweak boson production at LHCb

    Directory of Open Access Journals (Sweden)

    Wallace Ronan

    2013-11-01

    Full Text Available Measurements of W and Z boson production provide important tests of the Standard Model as well as being inputs for determining the parton density functions of the proton. W and Z production cross-sections, and their ratios, have been measured using the LHCb detector and are reported here. Datasets of up to 1 fb−1 at √s = 7 TeV are used.

  5. Domains of bosonic functional integrals

    International Nuclear Information System (INIS)

    We propose a mathematical framework for bosonic Euclidean quantum field functional integrals based on the theory of integration on the dual algebraic vector space of classical field sources. We present a generalization of the Minlos-Dao Xing theorem and apply it to determine exactly the domain of integration associated to the functional integral representation of the two-dimensional quantum electrodynamics Schwinger generating functional. (author)

  6. Collider Signatures of Goldstone Bosons

    CERN Document Server

    Cheung, Kingman; Yuan, Tzu-Chiang

    2014-01-01

    Recently Weinberg suggested that Goldstone bosons arising from the spontaneous breakdown of some global hidden symmetries can interact weakly in the early Universe and account for a fraction of the effective number of neutrino species N_{eff}, which has been reported persistently 2\\sigma away from its expected value of three. In this work, we study in some details a number of experimental constraints on this interesting idea based on the simplest possibility of a global U(1), as studied by Weinberg. We work out the decay branching ratios of the associated light scalar field \\sigma and suggest a possible collider signature at the Large Hadron Collider (LHC). In some corners of the parameter space, the scalar field \\sigma can decay into a pair of pions with a branching ratio of order 10% while the rest is mostly a pair of Goldstone bosons. The collider signature would be gluon fusion into the standard model Higgs boson gg -> H followed by H -> \\sigma \\sigma -> (\\pi\\pi) (\\alpha\\alpha) where \\alpha is the Goldsto...

  7. Query Expansion Based on Clustered Results

    CERN Document Server

    Liu, Ziyang; Chen, Yi

    2011-01-01

    Query expansion is a functionality of search engines that suggests a set of related queries for a user-issued keyword query. Typical corpus-driven keyword query expansion approaches return popular words in the results as expanded queries. Using these approaches, the expanded queries may correspond to a subset of possible query semantics, and thus miss relevant results. To handle ambiguous queries and exploratory queries, whose result relevance is difficult to judge, we propose a new framework for keyword query expansion: we start with clustering the results according to user specified granularity, and then generate expanded queries, such that one expanded query is generated for each cluster whose result set should ideally be the corresponding cluster. We formalize this problem and show its APX-hardness. Then we propose two efficient algorithms named iterative single-keyword refinement and partial elimination based convergence, respectively, which effectively generate a set of expanded queries from clustered r...

  8. Distinguishing a SM-like MSSM Higgs boson from SM Higgs boson at muon collider

    Indian Academy of Sciences (India)

    Jai Kumar Singhal; Sardar Singh; Ashok K Nagawat

    2007-06-01

    We explore the possibility of distinguishing the SM-like MSSM Higgs boson from the SM Higgs boson via Higgs boson pair production at future muon collider. We study the behavior of the production cross-section in SM and MSSM with Higgs boson mass for various MSSM parameters tan and A. We observe that at fixed CM energy, in the SM, the total cross-section increases with the increase in Higgs boson mass whereas this trend is reversed for the MSSM. The changes that occur for the MSSM in comparison to the SM predictions are quantified in terms of the relative percentage deviation in cross-section. The observed deviations in cross-section for different choices of Higgs boson masses suggest that the measurements of the cross-section could possibly distinguish the SM-like MSSM Higgs boson from the SM Higgs boson.

  9. CMS standard model Higgs boson results

    Directory of Open Access Journals (Sweden)

    Garcia-Abia Pablo

    2013-11-01

    Full Text Available In July 2012 CMS announced the discovery of a new boson with properties resembling those of the long-sought Higgs boson. The analysis of the proton-proton collision data recorded by the CMS detector at the LHC, corresponding to integrated luminosities of 5.1 fb−1 at √s = 7 TeV and 19.6 fb−1 at √s = 8 TeV, confirm the Higgs-like nature of the new boson, with a signal strength associated with vector bosons and fermions consistent with the expectations for a standard model (SM Higgs boson, and spin-parity clearly favouring the scalar nature of the new boson. In this note I review the updated results of the CMS experiment.

  10. UML-ising formal techniques

    DEFF Research Database (Denmark)

    Bjørner, Dines; George, Chris W.; Haxthausen, Anne Elisabeth;

    2004-01-01

    This invited paper presents a number of correlated specifications of example railway system problems. They use a variety of partially or fully integrated formal specification. The paper thus represents a mere repository of what we consider interesting case studies. The existence of the Unified...... these different UML views are unified, integrated, correlated or merely co-located is for others to dispute. We also seek to support multiple views, but are also in no doubt that there must be sound, well defined relations between such views. We thus report on ways and means of integrating formal...... techniques such as RAISE (RSL) [58,59], Petri Nets [56,62,37,61,411, Message and Live Sequence Charts [42,43,44,64,13], Statecharts [23,24,26,27], RAISE with Timing (TRSL) [18,45,461, and TRSL with Duration Calculus (79,30]. In this way one achieves a firm foundation for combined uses of these formal...

  11. A semiclassical approach for the Higgs boson

    CERN Document Server

    Fariborz, Amir H; Schechter, Joseph

    2014-01-01

    Starting from the equations of motion of the fields involved in a theory with spontaneous symmetry breaking and by making simple assumptions regarding their behavior we derive simple tree level relations between the mass of the Higgs boson in the theory and the masses of the gauge bosons corresponding to the broken generators. We show that these mass relations have a clear meaning if both the scalars and the gauge bosons are composite states made of two fermions.

  12. Fermionic subspaces of the bosonic string

    Energy Technology Data Exchange (ETDEWEB)

    Chattaraputi, Auttakit [Department of Physics, University of Chulalongkorn, Bangkok 10330 (Thailand); Englert, Francois [Service de Physique Theorique, Universite Libre de Bruxelles, Campus Plaine, CP 225, Boulevard du Triomphe, B-1050 Bruxelles (Belgium); Houart, Laurent [Service de Physique Theorique et Mathematique, Universite Libre de Bruxelles, Campus Plaine CP 231, Boulevard du Triomphe, B-1050 Brussells (Belgium); Taormina, Anne [Department of Mathematical Sciences, University of Durham, South Road, DH1 3LE Durham (United Kingdom)

    2003-06-21

    A universal symmetric truncation of the bosonic string Hilbert space yields all known closed fermionic string theories in ten dimensions, their D-branes and their open descendants. We highlight the crucial role played by group theory and two-dimensional conformal field theory in the construction and emphasize the predictive power of the truncation. Such circumstantial evidence points towards the existence of a mechanism which generates spacetime fermions out of bosons dynamically within the framework of bosonic string theory.

  13. Fermionic Subspaces of the Bosonic String

    CERN Document Server

    Chattaraputi, A; Houart, L; Taormina, A; Chattaraputi, Auttakit; Englert, Francois; Houart, Laurent; Taormina, Anne

    2003-01-01

    A universal symmetric truncation of the bosonic string Hilbert space yields all known closed fermionic string theories in ten dimensions, their D-branes and their open descendants. We highlight the crucial role played by group theory and two-dimensional conformal field theory in the construction and emphasize the predictive power of the truncation. Such circumstantial evidence points towards the existence of a mechanism which generates space-time fermions out of bosons dynamically within the framework of bosonic string theory.

  14. Fermionic Subspaces of the Bosonic String

    Science.gov (United States)

    Chattaraputi, A.; Englert, F.; Houart, L.; Taormina, A.

    A universal symmetric truncation of the bosonic string Hilbert space yields all known closed fermionic string theories in ten dimensions, their D-branes and their open descendants. We highlight the crucial role played by group theory and two-dimensional conformal field theory in the construction and emphasize the predictive power of the truncation. Such circumstantial evidence points towards the existence of a mechanism which generates space-time fermions out of bosons dynamically within the framework of bosonic string theory.

  15. The derivative expansion approach to the interaction between close surfaces

    CERN Document Server

    Fosco, C D; Mazzitelli, F D

    2014-01-01

    The derivative expansion approach to the calculation of the interaction between two surfaces, is a generalization of the proximity force approximation, a technique of widespread use in different areas of physics. The derivative expansion has so far been applied to seemingly unrelated problems in different areas; it is our principal aim here to present the approach in its full generality. To that end, we introduce an unified setting, which is independent of any particular application, provide a formal derivation of the derivative expansion in that general setting, and study some its properties. With a view on the possible application of the derivative expansion to other areas, like nuclear and colloidal physics, we also discuss the relation between the derivative expansion and some time-honoured uncontrolled approximations used in those contexts. By putting them under similar terms as the derivative expansion, we believe that the path is open to the calculation of next to leading order corrections also for tho...

  16. Testing the Higgs Boson Coupling to Gluons

    CERN Document Server

    Langenegger, Urs; Strebel, Ivo

    2015-01-01

    We study the possibility to separate in gluon fusion loop-induced Higgs boson production from point-like production. The Higgs boson is reconstructed in the Hgg final state at very large transverse momentum. Using the Higgs boson yields (normalized to the overall rate) and the shape of the Higgs boson pt distribution the two hypotheses can be separated with 2 standard deviations with an integrated luminosity of about 500 fb^-1. The largest experimental uncertainty affecting this estimate is the background event yield. The theoretical uncertainties from missing top mass effects are large, but can be decreased with dedicated calculations.

  17. Physics of W bosons at LEP

    CERN Document Server

    Mele, S

    2004-01-01

    The high-energy and high-luminosity data-taking campaigns of the LEP e+e- collider provided the four collaborations, ALEPH, DELPHI, L3 and OPAL, with about 50 000 W-boson pairs and about a thousand singly-produced W bosons. This unique data sample has an unprecedented reach in probing some aspects of the Standard Model of the electroweak interactions, and this article reviews several achievements in the understanding of W-boson physics at LEP. The measurements of the cross sections for W-boson production are discussed, together with their implication on the existence of the coupling between Z and W bosons. The precision measurements of the magnitude of triple gauge-boson couplings are presented. The observation of the longitudinal helicity component of the W-boson spin, related to the mechanism of electroweak symmetry breaking, is described together with the techniques used to probe the CP and CPT symmetries in the W-boson system. A discussion on the intricacies of the measurement of the mass of the W boson, ...

  18. Rotating Boson Stars and Q-Balls

    CERN Document Server

    Kleihaus, B; List, M; Kleihaus, Burkhard; Kunz, Jutta; List, Meike

    2005-01-01

    We consider axially symmetric, rotating boson stars. Their flat space limits represent spinning Q-balls. We discuss their properties and determine their domain of existence. Q-balls and boson stars are stationary solutions and exist only in a limited frequency range. The coupling to gravity gives rise to a spiral-like frequency dependence of the boson stars. We address the flat space limit and the limit of strong gravitational coupling. For comparison we also determine the properties of spherically symmetric Q-balls and boson stars.

  19. Rényi entropies of free bosons on the torus and holography

    International Nuclear Information System (INIS)

    We analytically evaluate the Rényi entropies for the two dimensional free boson CFT. The CFT is considered to be compactified on a circle and at finite temperature. The Rényi entropies Sn are evaluated for a single interval using the two point function of bosonic twist fields on a torus. For the case of the compact boson, the sum over the classical saddle points results in the Riemann-Siegel theta function associated with the An−1 lattice. We then study the Rényi entropies in the decompactification regime. We show that in the limit when the size of the interval becomes the size of the spatial circle, the entanglement entropy reduces to the thermal entropy of free bosons on a circle. We then set up a systematic high temperature expansion of the Rényi entropies and evaluate the finite size corrections for free bosons. Finally we compare these finite size corrections both for the free boson CFT and the free fermion CFT with the one-loop corrections obtained from bulk three dimensional handlebody spacetimes which have higher genus Riemann surfaces as its boundary. One-loop corrections in these geometries are entirely determined by quantum numbers of the excitations present in the bulk. This implies that the leading finite size corrections contributions from one-loop determinants of the Chern-Simons gauge field and the Dirac field in the dual geometry should reproduce that of the free boson and the free fermion CFT respectively. By evaluating these corrections both in the bulk and in the CFT explicitly we show that this expectation is indeed true

  20. Leibniz' First Formalization of Syllogistics

    DEFF Research Database (Denmark)

    Robering, Klaus

    2014-01-01

    In his Dissertatio de Arte Combinatoria from 1666 Leibniz provides a formal presentation of syllogistics within the framework of his general-combinatoric program. He does not set up an axiomatic system for the derivation of all valid syllogistic mode, rather he formulates a set of rules which dis...

  1. The Role of Formal Instruction

    Institute of Scientific and Technical Information of China (English)

    Sun Yu

    2011-01-01

    This paper looks at second language acquisition in a classroom setting. It considers whether formal instruction makes a difference to SLA. This is an important issue, because it address the question of the role played by environmental factors in SLA. It is also an important educational issue, as language pedagogy has traditionally operated on the assumption that grammar can be taught.

  2. Formal Institutions and Subjective Wellbeing

    DEFF Research Database (Denmark)

    Bjørnskov, Christian; Dreher, Axel; Fischer, Justina A.V.

    2010-01-01

    cross-country studies on the institution-happiness association. Our findings suggest that their conclusions are qualitatively rather insensitive to the specific measure of 'happiness' used, while the associations between formal institutions and subjective well-being differ among poor and rich countries...

  3. Formal Institutions and Subjective Wellbeing

    DEFF Research Database (Denmark)

    Bjørnskov, Christian; Dreher, Axel; Fischer, Justina

    A long tradition in economics explores the association between the quality of formal institutions and economic performance. The literature on the relationship between such institutions and happiness is, however, rather limited. In this paper, we revisit the findings from recent cross-country stud...

  4. Cohomology and the operator formalism

    International Nuclear Information System (INIS)

    This letter points a close parallel between the operator formalism for string theory and the action of a Lie algebra on a differential complex. The construction of conformal field theories can then be regarded as a cohomology problem; we suggest that this viewpoint may survive the generalization beyond finite genus Riemann surfaces. (orig.)

  5. Formal Verification of Continuous Systems

    DEFF Research Database (Denmark)

    Sloth, Christoffer

    2012-01-01

    losses. Furthermore, a malfunction in the control system of a surgical robot may cause death of patients. The previous examples involve complex systems that are required to operate according to complex specifications. The systems cannot be formally verified by modern verification techniques, due to the...

  6. A Formal Calculus for Categories

    DEFF Research Database (Denmark)

    Cáccamo, Mario José

    This dissertation studies the logic underlying category theory. In particular we present a formal calculus for reasoning about universal properties. The aim is to systematise judgements about functoriality and naturality central to categorical reasoning. The calculus is based on a language which...

  7. Ambitwistor String Theory in the Operator Formalism

    OpenAIRE

    Reid-Edwards, R. A.

    2015-01-01

    After a brief overview of the operator formalism for conventional string theory, an operator formalism for ambitwistor string theory is presented. It is shown how tree level supergravity scattering amplitudes are recovered in this formalism. More general applications of this formalism to loop amplitudes and the construction of an ambitwistor string field theory are briefly discussed.

  8. Ambitwistor string theory in the operator formalism

    Science.gov (United States)

    Reid-Edwards, R. A.

    2016-06-01

    After a brief overview of the operator formalism for conventional string theory, an operator formalism for ambitwistor string theory is presented. It is shown how tree level supergravity scattering amplitudes are recovered in this formalism. More general applications of this formalism to loop amplitudes and the construction of an ambitwistor string field theory are briefly discussed.

  9. Light composite Higgs boson from the normalized Bethe-Salpeter equation

    OpenAIRE

    Doff, A.(Universidade Tecnológica Federal do Paraná – UTFPR – DAFIS, Av. Monteiro Lobato Km 04, 84016-210 Ponta Grossa, PR, Brazil); Natale, A. A.; da Silva, P. S. Rodrigues

    2009-01-01

    Scalar composite boson masses have been computed in QCD and Technicolor theories with the help of the homogeneous Bethe-Salpeter equation (BSE), resulting in a scalar mass that is twice the dynamically generated fermion or technifermion mass ($m_{dyn}$). We show that in the case of walking (or quasi-conformal) technicolor theories, where the $m_{dyn}$ behavior with the momenta may be quite different from the one predicted by the standard operator product expansion, this result is incomplete a...

  10. Strong-coupling solution of the bosonic dynamical mean-field theory

    Czech Academy of Sciences Publication Activity Database

    Kauch, Anna; Byczuk, K.; Vollhardt, D.

    2012-01-01

    Roč. 85, č. 20 (2012), "205115-1"-"205115-7". ISSN 1098-0121 Institutional research plan: CEZ:AV0Z10100520 Keywords : strongly correlated bosons * dynamical mean-field theory * linked-cluster expansion * optical lattices * Mott insulators * superfluid Subject RIV: BE - Theoretical Physics Impact factor: 3.767, year: 2012 http://prb.aps.org/abstract/PRB/v85/i20/e205115

  11. Landau-Yang theorem and decays of a Z' boson into two Z bosons.

    Science.gov (United States)

    Keung, Wai-Yee; Low, Ian; Shu, Jing

    2008-08-29

    We study the decay of a Z' boson into two Z bosons by extending the Landau-Yang theorem to a parent particle decaying into two Z bosons. For a spin-1 parent the theorem predicts that (1) there are only two possible couplings and (2) the normalized differential cross section depends on kinematics only through a phase shift in the azimuthal angle between the two decay planes of the Z boson. When the parent is a Z' the two possible couplings are anomaly induced and CP violating, respectively. At the CERN Large Hadron Collider their effects could be disentangled when both Z bosons decay leptonically. PMID:18851602

  12. $3d$ fermion-boson map with imaginary chemical potential

    CERN Document Server

    Filothodoros, E G; Vlachos, N D

    2016-01-01

    We study the three-dimensional $U(N)$ Gross-Neveu and CP$^{N-1}$ models in the canonical formalism with fixed $U(1)$ charge. For large-$N$ this is closely related to coupling the models to abelian Chern-Simons in a monopole background. We show that the presence of the imaginary chemical potential for the $U(1)$ charge makes the phase structure of the models remarkably similar. We calculate their respective large-$N$ free energy densities and show that they are mapped into each other in a precise way. Intriguingly, the free energy map involves the Bloch-Wigner function and its generalizations introduced by Zagier. We expect that our results are connected to the recently discussed $3d$ bosonization.

  13. MSSM Higgs bosons production at e+e- colliders

    International Nuclear Information System (INIS)

    We study the production of the Higgs bosons predicted in the Minimal Supersymmetric extension of the Standard Model (h0,H0,A0,H±), with the reactions e+e- → bb-barh0(H0,A0), and e+e- → τ-v-barτH+,τ+vτH-, using the helicity formalism. We evaluate cross section of h0,H0,A0 and H± in the limit when tanβ is large. The numerical computation is done considering two stages of a possible Next Linear e+e- Collider: the first with √(s) = 500 GeV and design luminosity 50 fb-1, and the second with √(s) = 1 TeV and luminosity 100-200 fb-1

  14. Quantum state majorization at the output of bosonic Gaussian channels.

    Science.gov (United States)

    Mari, A; Giovannetti, V; Holevo, A S

    2014-01-01

    Quantum communication theory explores the implications of quantum mechanics to the tasks of information transmission. Many physical channels can be formally described as quantum Gaussian operations acting on bosonic quantum states. Depending on the input state and on the quality of the channel, the output suffers certain amount of noise. For a long time it has been conjectured, but never proved, that output states of Gaussian channels corresponding to coherent input signals are the less noisy ones (in the sense of a majorization criterion). Here we prove this conjecture. Specifically we show that every output state of a phase-insensitive Gaussian channel is majorized by the output state corresponding to a coherent input. The proof is based on the optimality of coherent states for the minimization of strictly concave output functionals. Moreover we show that coherent states are the unique optimizers. PMID:24806909

  15. On Nonlinear Bosonic Coherent States

    CERN Document Server

    Genovese, Marco; Rasetti, Mario

    2009-01-01

    Nonlinear coherent states are an interesting resource for quantum technologies. Here we investigate some critical features of the single-boson nonlinear coherent states, which are theoretically constructed as eigenstates of the annihilation operator and experimentally realized as stationary states of a trapped laser-driven ion. We show that the coherence and the minimum-uncertainty properties of such states are broken for values of the Lamb-Dicke parameter corresponding to the roots of the Laguerre polynomials, which enter their explicit expression. The case of the multiboson nonlinear coherent states is also discussed.

  16. The study of the W boson

    CERN Document Server

    Buchmüller, O L; Thompson, J C

    2002-01-01

    the status of the measurement of the W boson mass at LEP-2 is reviewed. Properties of the W such as branching ration into quarks and leptons and couplings to other neutral gauge bosons are reported. 4-fermion production cross-sections in e sup + e sup - collisions are also presented. (authors)

  17. Analysis of boson cascade laser characteristics

    Science.gov (United States)

    Ivanov, K. A.; Kaliteevskaya, N. A.; Gubaidullin, A. R.; Kaliteevski, M. A.

    2015-11-01

    The dependence of the level population on pumping in a boson cascade laser has been theoretically studied. Analytical expressions for the population of various cascade levels and the terahertz mode below and above the pumping threshold are obtained. Formulas for the pumping threshold and external quantum efficiency of the boson cascade laser are derived.

  18. Rare Decays of Z-boson

    OpenAIRE

    Jalilian-Marian, Jamal

    1994-01-01

    We study radiative decay modes of the Z-boson into heavy quark bound states. We find that the widths for these decays are extremely small. We conclude that these decays will not be detectable for the time being unless there is a significant increase in the number of Z-bosons produced at the electron- positron colliders.

  19. Diffractive Higgs Boson photoproduction in peripheral collisions

    International Nuclear Information System (INIS)

    An alternative process is proposed for the diffractive Higgs boson production inspired in the Durham model, exploring it through the photon-proton interaction. In this sense, we estimate the production cross section of the Higgs boson, comparing some sets of parton distributions in the proton and confronting this results with those from other processes. (author)

  20. Goldstone Bosons as Fractional Cosmic Neutrinos

    CERN Document Server

    Weinberg, Steven

    2013-01-01

    It is suggested that Goldstone bosons may be masquerading as fractional cosmic neutrinos, contributing about 0.39 to what is reported as the effective number of neutrino types in the era before recombination. The broken symmetry associated with these Goldstone bosons is further speculated to be the conservation of the particles of dark matter.

  1. Electroweak gauge boson polarisation at the LHC

    CERN Document Server

    Stirling, W J

    2012-01-01

    We study the polarisation of gauge bosons produced at the LHC. Polarisation effects for W bosons manifest themselves in the angular distributions of the lepton and in the distributions of lepton transverse momentum and missing transverse energy. The distributions also depend on the selection cuts, with kinematic effects competing with polarisation effects. The polarisation is discussed for a range of different processes producing W bosons: W+jets, W from top (single and pair) production, W pair production and W production in association with a Z or Higgs boson. The relative contributions of the different polarisation states varies from process to process, reflecting the dynamics of the underlying hard-scattering process. We also present results for the polarisation of the Z boson produced in association with QCD jets at the LHC, and comment on the differences between W and Z production.

  2. The Boson peak in supercooled water.

    Science.gov (United States)

    Kumar, Pradeep; Wikfeldt, K Thor; Schlesinger, Daniel; Pettersson, Lars G M; Stanley, H Eugene

    2013-01-01

    We perform extensive molecular dynamics simulations of the TIP4P/2005 model of water to investigate the origin of the Boson peak reported in experiments on supercooled water in nanoconfined pores, and in hydration water around proteins. We find that the onset of the Boson peak in supercooled bulk water coincides with the crossover to a predominantly low-density-like liquid below the Widom line TW. The frequency and onset temperature of the Boson peak in our simulations of bulk water agree well with the results from experiments on nanoconfined water. Our results suggest that the Boson peak in water is not an exclusive effect of confinement. We further find that, similar to other glass-forming liquids, the vibrational modes corresponding to the Boson peak are spatially extended and are related to transverse phonons found in the parent crystal, here ice Ih. PMID:23771033

  3. Search for new heavy charged gauge bosons

    Energy Technology Data Exchange (ETDEWEB)

    Magass, Carsten Martin [RWTH Aachen Univ. (Germany)

    2007-11-02

    Additional gauge bosons are introduced in many theoretical extensions to the Standard Model. A search for a new heavy charged gauge boson W' decaying into an electron and a neutrino is presented. The data used in this analysis was taken with the D0 detector at the Fermilab proton-antiproton collider at a center-of-mass energy of 1.96 TeV and corresponds to an integrated luminosity of about 1 fb-1. Since no significant excess is observed in the data, an upper limit is set on the production cross section times branching fraction σW'xBr (W' → ev). Using this limit, a W' boson with mass below ~1 TeV can be excluded at the 95% confidence level assuming that the new boson has the same couplings to fermions as the Standard Model W boson.

  4. Search for new heavy charged gauge bosons

    Energy Technology Data Exchange (ETDEWEB)

    Magass, Carsten Martin; /RWTH Aachen U.

    2007-11-01

    Additional gauge bosons are introduced in many theoretical extensions to the Standard Model. A search for a new heavy charged gauge boson W{prime} decaying into an electron and a neutrino is presented. The data used in this analysis was taken with the D0 detector at the Fermilab proton-antiproton collider at a center-of-mass energy of 1.96 TeV and corresponds to an integrated luminosity of about 1 fb{sup -1}. Since no significant excess is observed in the data, an upper limit is set on the production cross section times branching fraction {sigma}{sub W{prime}}xBr (W{prime} {yields} e{nu}). Using this limit, a W{prime} boson with mass below {approx}1 TeV can be excluded at the 95% confidence level assuming that the new boson has the same couplings to fermions as the Standard Model W boson.

  5. Orbital dynamics of binary boson star systems

    International Nuclear Information System (INIS)

    We extend our previous studies of head-on collisions of boson stars by considering orbiting binary boson stars. We concentrate on equal-mass binaries and study the dynamical behavior of boson/boson and boson/antiboson pairs. We examine the gravitational wave output of these binaries and compare with other compact binaries. Such a comparison lets us probe the apparent simplicity observed in gravitational waves produced by black hole binary systems. In our system of interest however, there is an additional internal freedom which plays a significant role in the system's dynamics, namely, the phase of each star. Our evolutions show rather simple behavior at early times, but large differences occur at late times for the various initial configurations

  6. Various Models Mimicking the SM Higgs Boson

    CERN Document Server

    Chang, Jung; Tseng, Po-Yan; Yuan, Tzu-Chiang; 10.1142/S0217751X1230030X

    2012-01-01

    This review is based on the talk presented at the SUSY 2012 (Beijing). The new particle around 125 GeV observed at the Large Hadron Collider (LHC) is almost consistent with the standard model Higgs boson, except that the diphoton decay mode may be excessive. We summarize a number of possibilities. While at the LHC the dominant production mechanism for the Higgs boson of the standard model and some other extensions is via the gluon fusion process, the alternative vector-boson fusion is more sensitive to electroweak symmetry breaking. Using the well known dijet-tagging technique to single out the vector-boson fusion mechanism, we investigate potential of vector-boson fusion to discriminate a number of models suggested to give an enhanced inclusive diphoton production rate.

  7. Boson Sampling for Molecular Vibronic Spectra

    CERN Document Server

    Huh, Joonsuk; Peropadre, Borja; McClean, Jarrod R; Aspuru-Guzik, Alán

    2014-01-01

    Quantum computers are expected to be more efficient in performing certain computations than any classical machine. Unfortunately, the technological challenges associated with building a full-scale quantum computer have not yet allowed the experimental verification of such an expectation. Recently, boson sampling has emerged as a problem that is suspected to be intractable on any classical computer, but efficiently implementable with a linear quantum optical setup. Therefore, boson sampling may offer an experimentally realizable challenge to the Extended Church-Turing thesis and this remarkable possibility motivated much of the interest around boson sampling, at least in relation to complexity-theoretic questions. In this work, we show that the successful development of a boson sampling apparatus would not only answer such inquiries, but also yield a practical tool for difficult molecular computations. Specifically, we show that a boson sampling device with a modified input state can be used to generate molecu...

  8. Notoph gauge theory: superfield formalism

    International Nuclear Information System (INIS)

    We derive absolutely anticommuting Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST symmetry transformations for the 4D free Abelian 2-form gauge theory by exploiting the superfield approach to BRST formalism. The antisymmetric tensor gauge field of the above theory was christened as the 'notoph' (i.e., the opposite of 'photon') gauge field by Ogievetsky and Polubarinov way back in 1966-67. We briefly outline the problems involved in obtaining the absolute anticommutativity of the (anti-)BRST formalism. One of the highlights of our results is the emergence of a Curci-Ferrari type of restriction in the context of 4D Abelian 2-form (notoph) gauge theory which renders the nilpotent (anti-)BRST symmetries of the theory to be absolutely anticommutative in nature

  9. Informal work and formal plans

    DEFF Research Database (Denmark)

    Dalsted, Rikke Juul; Hølge-Hazelton, Bibi; Kousgaard, Marius Brostrøm;

    2012-01-01

    trajectories. METHODS AND THEORY: An in-depth case study of patient trajectories at a Danish hospital and surrounding municipality using individual interviews with patients. Theory about trajectory and work by Strauss was included. RESULTS: Patients continuously took initiatives to organize their treatment...... and care. They initiated processes in the trajectories, and acquired information, which they used to form their trajectories. Patients presented problems to the healthcare professionals in order to get proper help when needed. DISCUSSION: Work done by patients was invisible and not perceived as work....... The patients' requests were not sufficiently supported in the professional organisation of work or formal planning. Patients' insertion and use of information in their trajectories challenged professional views and working processes. And the design of the formal pathway models limits the patients' active...

  10. Methodology of formal software evaluation

    International Nuclear Information System (INIS)

    Sydkraft AB, the major Swedish utility, owner of ca 6000 MWel installed in nuclear (NPP Barsebaeck and NPP Oskarshamn), fossil fuel and hydro Power Plants is facing modernization of the control systems of the plants. Standards applicable require structured, formal methods for implementation of the control functions in the modem, real time software systems. This presentation introduces implementation methodology as discussed presently at the Sydkraft organisation. The approach suggested is based upon the process of co-operation of three parties taking part in the implementation; owner of the plant, vendor and Quality Assurance (QA) organisation. QA will be based on tools for formal software validation and on systematic gathering by the owner of validated and proved-by-operation control modules for the concern-wide utilisation. (author)

  11. Contextual approach to quantum formalism

    CERN Document Server

    Khrennikov, Andrei

    2009-01-01

    The aim of this book is to show that the probabilistic formalisms of classical statistical mechanics and quantum mechanics can be unified on the basis of a general contextual probabilistic model. By taking into account the dependence of (classical) probabilities on contexts (i.e. complexes of physical conditions), one can reproduce all distinct features of quantum probabilities such as the interference of probabilities and the violation of Bell’s inequality. Moreover, by starting with a formula for the interference of probabilities (which generalizes the well known classical formula of total probability), one can construct the representation of contextual probabilities by complex probability amplitudes or, in the abstract formalism, by normalized vectors of the complex Hilbert space or its hyperbolic generalization. Thus the Hilbert space representation of probabilities can be naturally derived from classical probabilistic assumptions. An important chapter of the book critically reviews known no-go theorems...

  12. Formal Verification of Quantum Protocols

    CERN Document Server

    Nagarajan, R; Nagarajan, Rajagopal; Gay, Simon

    2002-01-01

    We propose to analyse quantum protocols by applying formal verification techniques developed in classical computing for the analysis of communicating concurrent systems. One area of successful application of these techniques is that of classical security protocols, exemplified by Lowe's discovery and fix of a flaw in the well-known Needham-Schroeder authentication protocol. Secure quantum cryptographic protocols are also notoriously difficult to design. Quantum cryptography is therefore an interesting target for formal verification, and provides our first example; we expect the approach to be transferable to more general quantum information processing scenarios. The example we use is the quantum key distribution protocol proposed by Bennett and Brassard, commonly referred to as BB84. We present a model of the protocol in the process calculus CCS and the results of some initial analyses using the Concurrency Workbench of the New Century (CWB-NC).

  13. Extension of the consistent Q formalism to odd-A nuclei in the W-Pt region

    International Nuclear Information System (INIS)

    It is shown that the approach of the Consistent Q Formalism, which has proved successful in the Interacting Boson Model description of even-even nuclei, can be extended to odd A nuclei within the framework of the Interacting Boson-Fermion Model. The proposed method describes the transition between the SU(3) and O(6) symmetry limits of the U(6/12) boson fermion group, and can be applied to the odd neutron W, Os, Pt nuclei. As in the even-even case, a number of parameter-free predictions emerge for the transitional region concerning energies, B(E2) values and also single particle structure factors, and some of these are compared to existing data for the odd Os nuclei. 15 references

  14. Formal modelling of cognitive interpretation

    OpenAIRE

    Rukšenas, R.; Curzon, P.; Back, J.; Blandford, A.

    2007-01-01

    We formally specify the interpretation stage in a dual state space human-computer interaction cycle. This is done by extending/reorganising our previous cognitive architecture. In particular, we focus on shape related aspects of the interpretation process associated with device input prompts. A cash-point example illustrates our approach. Using the SAL model checking environment, we show how the extended cognitive architecture facilitates detection of prompt-shape induced human error. © Sprin...

  15. Stroh formalism and Rayleigh waves

    CERN Document Server

    Tanuma, Kazumi

    2008-01-01

    Introduces a powerful and elegant mathematical method for the analysis of anisotropic elasticity equationsThe reader can grasp the essentials as quickly as possibleCan be used as a textbook, which presents compactly introduction and applications of the Stroh formalismAppeals to the people not only in mathematics but also in mechanics and engineering sciencePrerequisites are only basic linear algebra, calculus and fundamentals of differential equations

  16. Geometrical formalism in gauge theories

    OpenAIRE

    Kubyshin, Yuri A.

    2003-01-01

    We review the basic elements of the geometrical formalism for description of gauge fields and the theory of invariant connections, and their applications to the coset space dimensional reduction of Yang-Mills theories. We also discuss the problem of classification of principal fibre bundles, which is important for the quantization of gauge theories. Some results for bundles over two-dimensional spaces are presented.

  17. Review of the helicity formalism

    International Nuclear Information System (INIS)

    Our purpose in these notes has been to present a brief and general review of the helicity formalism. We begin by discussing Lorentz invariance, spin and helicity ideas, in section 1 . In section 2 we deal with the construction of relativistic states and scattering amplitudes in the helicity basis and we study their transformation properties under discrete symmetries. Finally we present some more sophisticated topics like kinematical singularities of helicity amplitudes, kinematical constraints and crossing relations 3, 4, 5 respectively. (Author) 8 refs

  18. Formalizing Arrow’s theorem

    Indian Academy of Sciences (India)

    Freek Wiedijk

    2009-02-01

    A small project in which I encoded a proof of Arrow’s theorem—probably the most famous results in the economics field of social choice theory—in the computer using the Mizar system is presented here. The details of this specific project, as well as the process of formalization (encoding proofs in the computer) in general are discussed.

  19. Formal aspects of component software

    OpenAIRE

    Sun, Meng; Schatz, B.

    2014-01-01

    This issue includes extended versions of selected best papers from the 7th International Workshop on Formal Aspects of Component Software (FACS 2010) held in Guimarães, Portugal on October 14–16, 2010. The component-based software development approach has emerged as a promising paradigm to cope with an ever increasing complexity of present-day software solutions by bringing sound production and engineering principles into software engineering. However, many conceptual and technological iss...

  20. Formal Verification under Unknown Constraints

    Institute of Scientific and Technical Information of China (English)

    LI Guang-hui; LI Xiao-wei

    2005-01-01

    We present a formal method of verifying designs with unknown constraints (e. g. , black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) formulas. Furthermore, this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

  1. Higgs Boson - on Your Own

    CERN Document Server

    Csorgo, T

    2013-01-01

    One of the highlights of 2012 in physics is related to two papers, published by the ATLAS and the CMS Collaborations, that announced the discovery of at least one new particle in pp collisions at CERN LHC. At least one of the properties of this new particle is found to be similar to that of the Higgs boson, the last and most difficult to find building block from the Standard Model of particle physics. Physics teachers are frequently approached by their media-educated students, who inquire about the properties of the Higgs boson, but physics teachers are rarely trained to teach this elusive aspect of particle physics in elementary, middle or junior high schools. In this paper I describe a card-game, that can be considered as a hands-on and easily accessible tool that allows interested teachers, students and also motivated lay-persons to play with the properties of the newly found Higgs-like particle. This new particle was detected through its decays to directly observable, final state particles. Many of these ...

  2. From The Beatles to Bosons

    CERN Multimedia

    Stephanie McClellan

    2013-01-01

    Before embarking on a successful career as a musician, Alan Parsons started out as a sound engineer - earning his first credit on The Beatles’ Abbey Road.  Over the years, he has worked and collaborated with various artists, but 30 September 2013 marks a unique collaboration.  For CERN’s ‘Bosons & More’ party, Alan Parsons Live Project will be sharing the stage with the Orchestre de la Suisse Romande.  Having already visited CERN in 2011, Alan Parsons provides an insight into his views on science and his upcoming performance at the ‘Bosons & More’ event.     Alan Parsons during his visit to CERN in August 2011. Since visiting CERN in 2011, how have your feelings towards the Organization developed? I was thrilled to hear about the recent discovery and how years of work had paid off. Together with my wife, Lisa, and my band, we were very privileged to come to CERN a couple of years ago, hav...

  3. 1/N expansion in SUSY CPsup(N-1) model

    International Nuclear Information System (INIS)

    The 1/N expansion for supersymmetric two-dimensional CPsup(N-1) model has been constructed in the superfield formalism. The subtraction procedure and the way to choose manifestly supersymmetric gauge is formulated to define UV and IR regular Green functions for any given order in 1/N

  4. The essence of eta-expansion in partial evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier; Malmkjær, Karoline; Palsberg, Jens

    1995-01-01

    Selective eta-expansion is a powerful ldquobinding-time improvementrdquo,i.e., a source-program modification that makes a partial evaluator yield better results. But like most binding-time improvements, the exact problem it solves and the reason why have not been formalized and are only understood...

  5. New Exact Solutions for Konopelchenko-Dubrovsky Equation Using an Extended Riccati Equation Rational Expansion Method

    Institute of Scientific and Technical Information of China (English)

    SONG Li-Na; ZHANG Hong-Qing

    2006-01-01

    Taking the Konopelchenko-Dubrovsky system as a simple example, some families of rational formal hyperbolic function solutions, rational formal triangular periodic solutions, and rational solutions are constructed by using the extended Riccati equation rational expansion method presented by us. The method can also be applied to solve more nonlinear partial differential equation or equations.

  6. Ordering principle for cluster expansions in the theory of quantum fluids, dense gases, and simple classical liquids

    International Nuclear Information System (INIS)

    A study is made of a series-expansion procedure which gives the leading terms of the n-particle distribution function p/sup( n/)(1,2,...,n) as explicit functionals in the radial distribution function g(r). The development of the series is based on the cluster-expansion formalism applied to the Abe form for p/sup( n/) expressed as a product of the generalized Kirkwood superposition approximation P/sup( n/)/sub K/ and a correction factor exp[A/sup( n/)(1,2,...,n)]. An ordering parameter μ is introduced to determine A/sup( n/) and p/sup( n/) in the form of infinite power series in μ, and the postulate of minimal complexity is employed to eliminate an infinite number of possible classes of solutions in a sequential relation connecting A/sup( n/-1) and A/sup( n/). Derivation of the series for p/sup( n/) and many other algebraic manipulations involving a large number of cluster integrals are greatly simplified by the use of a scheme which groups together all cluster terms having, in a certain way, the same source term. In particular, the scheme is useful in demonstrating that the nature of the series structure of p/sup(3) is such that its three-point Fourier transform S/sup(3)(k1,k2,k3) has as a factor the product of the three liquid-structure functions S(k1)S(k2)S(k3). The results obtained to order μ4 for A/sup(3), p/sup(3), and S/sup(3) agree with those derived earlier in a more straightforward but tedious approach. The result for p/sup(4) shows that the convolution approximation p/sup(4)/sub c/, which contains μ3 terms, must be supplemented by a correction of O(μ3) in order to be accurate through third order. The μ-expansion approach is also examined for the cluster expansion of the correlation function in the Bijl-Dingle-Jastrow description of a many-boson system, and then compared with the number-density expansion formula by using the Gaussian model for g(r)-1 to evaluate cluster integrals

  7. Formal Analysis of Meaning in Natural Languages

    Directory of Open Access Journals (Sweden)

    Ljiljana Saric

    2006-06-01

    Full Text Available Broadly, the subject of this paper is the relation between logic and linguistics. More narrowly, it concentrates on formal semantics. The first part of the text discusses the topics and methods of formal semantics, and the second part the history of formal semantics. Formal semantic analysis has not been widely known and applied in our research community, and formal methods have been applied extremely rarely in linguistic analyses. This is why it is useful to point out the significant achievements of formal semantics. This inspiring interdisciplinary field of research has been successfully connecting research in linguistics, logic and philosophy since the early 1970s.

  8. Computer education in formal and non-formal education

    OpenAIRE

    Mrak Merhar, Irena

    2015-01-01

    During my work with the nongovermental youth organization Društvo mladinski ceh, the Computer studies at the Faculty of Education and working with my obligatory computer practice I've become acquainted with the formal and informal computer education. In my diploma I've asked myself how to improve both types of education, which are the weaknesses and the advantages with either computer education. In the first part of my diploma I studied all curricula for Computer science and Informatics f...

  9. Formal languages, automata and numeration systems, v.2

    CERN Document Server

    Rigo, Michel

    2014-01-01

    The interplay between words, computability, algebra and arithmetic has now proved its relevance and fruitfulness. Indeed, the cross-fertilization between formal logic and finite automata (such as that initiated by J.R. Büchi) or between combinatorics on words and number theory has paved the way to recent dramatic developments, for example, the transcendence results for the real numbers having a "simple" binary expansion, by B. Adamczewski and Y. Bugeaud. This book is at the heart of this interplay through a unified exposition. Objects are considered with a perspective that comes both from t

  10. Calculation of ionization within the close-coupling formalism

    International Nuclear Information System (INIS)

    A method for calculation of differential ionization cross sections from theories that use the close-coupling expansions for the total wave functions is presented. It is shown how from a single such calculation elastic, excitation, and ionization cross sections may be extracted using solely the T-matrix elements arising from solution of the coupled equations. To demonstrate the applicability of this formalism, the convergent close-coupling (CCC) theory is systematically applied at incident energies of 150-600 eV to the calculation of e-He ionization. Comparison with available measurements is generally very good. 50 refs., 17 figs

  11. Spin asymmetries for vector boson production in polarized p+p collisions

    CERN Document Server

    Huang, Jin; Vitev, Ivan; Xing, Hongxi

    2015-01-01

    We study the cross section for vector boson ($W^{\\pm}/Z^0/\\gamma^*$) production in polarized nucleon-nucleon collisions for low transverse momentum of the observed vector boson. For the case where one measures the transverse momentum and azimuthal angle of the vector bosons, we present the cross sections and the associated spin asymmetries in terms of transverse momentum dependent parton distribution functions (TMDs) at tree level within the TMD factorization formalism. To assess the feasibility of experimental measurements, we estimate the spin asymmetries for $W^{\\pm}/Z^0$ boson production in polarized proton-proton collisions at the Relativistic Heavy Ion Collider (RHIC) by using current knowledge of the relevant TMDs. We find that some of these asymmetries can be sizable if the suppression effect from TMD evolution is not too strong. The $W$ program at RHIC can, thus, test and constrain spin theory by providing unique information on the universality properties of TMDs, TMD evolution, and the nucleon struc...

  12. Spin asymmetries for vector boson production in polarized p +p collisions

    Science.gov (United States)

    Huang, Jin; Kang, Zhong-Bo; Vitev, Ivan; Xing, Hongxi

    2016-01-01

    We study the cross section for vector boson (W±/Z0/γ*) production in polarized nucleon-nucleon collisions for low transverse momentum of the observed vector boson. For the case where one measures the transverse momentum and azimuthal angle of the vector bosons, we present the cross sections and the associated spin asymmetries in terms of transverse momentum dependent parton distribution functions (TMDs) at tree level within the TMD factorization formalism. To assess the feasibility of experimental measurements, we estimate the spin asymmetries for W±/Z0 boson production in polarized proton-proton collisions at the Relativistic Heavy Ion Collider by using current knowledge of the relevant TMDs. We find that some of these asymmetries can be sizable if the suppression effect from TMD evolution is not too strong. The W program at RHIC can, thus, test and constrain spin theory by providing unique information on the universality properties of TMDs, TMD evolution, and the nucleon structure. For example, the single transverse spin asymmetries could be used to probe the well-known Sivers function f1T ⊥q, as well as the transversal helicity distribution g1T q via the parity-violating nature of W production.

  13. Effective Field Theory for Few-Boson Systems

    CERN Document Server

    Bazak, Betzalel; van Kolck, Ubirajara

    2016-01-01

    We study universal bosonic few-body systems within the framework of effective field theory at leading order (LO). We calculate binding energies of systems of up to six particles and the atom-dimer scattering length. Convergence to the limit of zero-range two- and three-body interactions is shown, indicating that no additional few-body interactions need to be introduced at LO. Generalizations of the Tjon line are constructed, showing correlations between few-body binding energies and the binding energy of the trimer, for a given dimer energy. As a specific example, we implement our theory for 4He atomic systems, and show that the results are in surprisingly good agreement with those of sophisticated 4He-4He potentials. Potential implications for the convergence of the EFT expansion are discussed.

  14. Higgs boson, renormalization group, and naturalness in cosmology

    International Nuclear Information System (INIS)

    We consider the renormalization group improvement in the theory of the Standard Model (SM) Higgs boson playing the role of an inflaton with a strong non-minimal coupling to gravity. At the one-loop level with the running of constants taken into account, it leads to a range of the Higgs mass that is entirely determined by the lower WMAP bound on the cosmic microwave background (CMB) spectral index. We find that the SM phenomenology is sensitive to current cosmological data, which suggests to perform more precise CMB measurements as a SM test complementary to the LHC program. By using the concept of a field-dependent cutoff, we show the naturalness of the gradient and curvature expansion in this model within the conventional perturbation theory range of the SM. We also discuss the relation of these results to two-loop calculations and the limitations of the latter caused by parametrization and gauge dependence problems. (orig.)

  15. Higgs boson research in e+e- collisions

    International Nuclear Information System (INIS)

    This lesson is about the experimental results obtained in 1990, at LEP concerning Higgs boson research. The main topics studied are: Higgs boson research of minimal Standard Model, then beyond the minimal model, the charged Higgs boson research in 2-doublets model, and finally, neutral Higgs boson research in a specific 2-doublets model, the minimal supersymmetric standard model

  16. MSSM Higgs Bosons at The LHC

    CERN Document Server

    Christensen, Neil; Su, Shufang

    2012-01-01

    The recent results on Higgs boson searches from LHC experiments provide significant guidance in exploring the Minimal Supersymmetric (SUSY) Standard Model (MSSM) Higgs sector. If we accept the existence of a SM-like Higgs boson in the mass window of 123 GeV-127 GeV as indicated by the observed gamma,gamma events, there are two distinct mass regions (in mA) left in the MSSM Higgs sector: (a) the lighter CP-even Higgs boson being SM-like and the non-SM-like Higgs bosons all heavy and nearly degenerate above 300 GeV (an extended decoupling region); (b) the heavier CP-even Higgs boson being SM-like and the neutral non-SM-like Higgs bosons all nearly degenerate around 100 GeV (a small non-decoupling region). On the other hand, due to the strong correlation between the Higgs decays to W+W- and to gamma,gamma predicted in the MSSM, the apparent absence of a W+W- final state signal is in direct conflict with the gamma,gamma peak. If the deficit in the W+W- channel persists, it would imply that the SM-like Higgs boson...

  17. Expansion for Universal Quantifiers

    CERN Document Server

    Lenglet, Sergueï

    2012-01-01

    Expansion is an operation on typings (i.e., pairs of typing environments and result types) defined originally in type systems for the lambda-calculus with intersection types in order to obtain principal (i.e., most informative, strongest) typings. In a type inference scenario, expansion allows postponing choices for whether and how to use non-syntax-driven typing rules (e.g., intersection introduction) until enough information has been gathered to make the right decision. Furthermore, these choices can be equivalent to inserting uses of such typing rules at deeply nested positions in a typing derivation, without needing to actually inspect or modify (or even have) the typing derivation. Expansion has in recent years become simpler due to the use of expansion variables (e.g., in System E). This paper extends expansion and expansion variables to systems with forall-quantifiers. We present System Fs, an extension of System F with expansion, and prove its main properties. This system turns type inference into a c...

  18. Composite Weak Bosons at the Large Hadronic Collider

    CERN Document Server

    Fritzsch, Harald

    2016-01-01

    In a composite model of the weak bosons the p-wave bosons are studied. The state with the lowest mass is identified with the boson, which has been discovered at the LHC. Specific properties of the excited bosons are discussed, in particular their decays into weak bosons and photons. Recently a two photon signal has been observed, which might come from the decay of a neutral heavy boson with a mass of about 0.75 TeV. This particle could be an excited weak tensor boson.

  19. Local spinfoam expansion in loop quantum cosmology

    CERN Document Server

    Henderson, Adam; Vidotto, Francesca; Wilson-Ewing, Edward

    2010-01-01

    The quantum dynamics of the flat Friedmann-Lemaitre-Robertson-Walker and Bianchi I models defined by loop quantum cosmology have recently been translated into a spinfoam-like formalism. The construction is facilitated by the presence of a massless scalar field which is used as an internal clock. The implicit integration over the matter variable leads to a nonlocal spinfoam amplitude. In this paper we consider a vacuum Bianchi I universe and show that by choosing an appropriate regulator a spinfoam expansion can be obtained without selecting a clock variable and that the resulting spinfoam amplitude is local.

  20. Cluster expansion in the truncated bootstrap model and linear graphs theory

    International Nuclear Information System (INIS)

    Using the formalism of linear graphs theory, we obtain the cluster expansion for the grand potential of interacting hadronic systems in the framework of the truncated bootstrap model. We show that the coefficients of the expansion are constructed from two classes of Cayley-tree graphs contributing with opposite sign, related to the two-phase nature of the truncated bootstrap model. (orig.)

  1. The Bondi-Sachs Formalism

    CERN Document Server

    Mädler, Thomas

    2016-01-01

    The Bondi-Sachs formalism of General Relativity is a metric-based treatment of the Einstein equations in which the coordinates are adapted to the null geodesics of the spacetime. It provided the first convincing evidence that gravitational radiation is a nonlinear effect of general relativity and that the emission of gravitational waves from an isolated system is accompanied by a mass loss from the system. The asymptotic behaviour of the Bondi-Sachs metric revealed the existence of the symmetry group at null infinity, the Bondi-Metzner-Sachs group, which turned out to be larger than the Poincare group.

  2. Knowledge formalization of intelligent building

    Science.gov (United States)

    Žáček, Martin

    2016-06-01

    This article aim is understanding the basic knowledge about an intelligent building. The notion of the intelligent building can be called any building equipped with computer and communication technology, which can automatically respond to internal or external stimuli. The result of the intelligent building is an automated and foreseeing of activities that enable to reduce operating costs and increase comfort. The best way to use the intelligent building is for a low-energy building, a passive building, or for building with high savings. The output of this article is the formalization of basic knowledge of the intelligent building by RDF graph.

  3. Measuring the effect of formalization

    International Nuclear Information System (INIS)

    We present an ongoing research activity concerned with measuring the effect of an increased level of formalization in software development. We summarize the experiences from a first experimental development. Based on these experiences, we discuss a number of technical issues; in particular, problems connected to metrics based on fault reports. First of all, what is a fault? Secondly, how should the fault counting be integrated in the development process? Thirdly, any reasonable definition of fault depends on a notion of satisfaction. Hence, we must address the question: What does it mean for a specification or an implementation to satisfy a requirement imposed by a more high-level specification? (author)

  4. Quantum mechanics principles and formalism

    CERN Document Server

    McWeeny, R

    2013-01-01

    Quantum Mechanics: Principles and Formalism gives importance to the exposition of the fundamental bases of quantum mechanics. This text first discusses the physical basis of quantum theory. This book then provides some simple solutions of Schrödinger's equation, eigenvalue equations, and general formulation of quantum mechanics. The general theory of representations is also tackled. In discussing this topic, this text specifically looks into the harmonic oscillator, Dirac notation, time-evolution, Schrödinger equation in momentum space, and transformation theory. This publication will be inv

  5. Search for a Higgs Boson Decaying to Weak Boson Pairs at LEP

    CERN Document Server

    Achard, P; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Baldew, S V; Banerjee, S; Banerjee, Sw; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiefari, G; Cifarelli, Luisa; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; van Dalen, J A; De Asmundis, R; Déglon, P L; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau, D; Duda, M; Echenard, B; Eline, A; El-Hage, A; El-Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Guida, M; van Gulik, R; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hakobyan, R S; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Käfer, D; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kräber, M H; Krämer, R W; Krüger, A; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Levtchenko, M; Levchenko, P M; Li, C; Likhoded, S; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Luci, C; Luminari, L; Lustermann, W; Ma Wen Gan; Malgeri, L; Malinin, A; Maña, C; Mangeol, D J J; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Nowak, H; Ofierzynski, R A; Organtini, G; Palomares, C; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofiev, D O; Prokofev, D; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P A; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosier-Lees, S; Roth, S; Rosenbleck, C; Roux, B; Rubio, J A; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Sanders, M P; Schäfer, C; Shchegelskii, V; Schopper, Herwig Franz; Schotanus, D J; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A V; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, Ludwig; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Ulbricht, J; Valente, E; Van de Walle, R T; Vásquez, R; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, Gert M; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, X L; Wang, Z M; Weber, M; Wienemann, P; Wilkens, H; Wynhoff, S; Xia, L; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhao, J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zichichi, A; Zimmermann, B; Zöller, M

    2003-01-01

    A Higgs particle produced in association with a Z boson and decaying into weak boson pairs is searched for in 336.4 1/pb of data collected by the L3 experiment at LEP at centre-of-mass energies from 200 to 209 GeV. Limits on the branching fraction of the Higgs boson decay into two weak bosons as a function of the Higgs mass are derived. These results are combined with the L3 search for a Higgs boson decaying to photon pairs. A Higgs produced with a Standard Model e+e- --> Zh cross section and decaying only into electroweak boson pairs is excluded at 95% CL for a mass below 107 GeV.

  6. Bosonic string theory with dust

    International Nuclear Information System (INIS)

    We study a modified bosonic string theory that has a pressureless ‘dust’ field on the string worldsheet. The dust is a real scalar field with unit gradient which breaks conformal invariance. Hamiltonian analysis reveals a time reparametrization constraint linear in the dust field momentum and a spatial diffeomorphism constraint. This feature provides a natural ‘dust time’ gauge in analogy with the parametrized particle. In this gauge we give a Fock quantization of the theory, which is complete and self-consistent in d < 26. The Hamiltonian of the theory is not a constraint; as a consequence the Hilbert space and mass spectrum are characterized by an additional parameter, and includes the usual string spectrum as a special case. The other sectors provide new particle spectra, some of which do not have tachyons. (paper)

  7. Leptogenesis and neutral gauge bosons

    CERN Document Server

    Heeck, Julian

    2016-01-01

    We consider low-scale leptogenesis via right-handed neutrinos $N$ coupled to a $Z'$ boson, with gauged $U(1)_{B-L}$ as a simple realization. Keeping the neutrinos sufficiently out of equilibrium puts strong bounds on the $Z'$ coupling strength and mass, our focus being on light $Z'$ and $N$, testable in the near future by SHiP, HPS, Belle II, and at the LHC. We show that leptogenesis could be robustly falsified in a large region of parameter space by the double observation of $Z'$ and $N$, e.g. in the channel $pp\\to Z' \\to NN$ with displaced $N$-decay vertex, and by several experiments searching for light $Z'$, according to the mass of $N$.

  8. Is my boson sampler working?

    Science.gov (United States)

    Bentivegna, Marco; Spagnolo, Nicolò; Sciarrino, Fabio

    2016-04-01

    Is it possible to assess the correct functioning of a quantum device which eludes efficient computation of the expected results? The BosonSampling protocol is one of the best candidates to experimentally demonstrate the superior computational power of quantum mechanics, but the problem of its results certification requires the development of new methodologies, when the size of the problem becomes too large for a complete classical simulation. A recent work (Walschaers et al 2016 New J. Phys. 18 032001) has provided a significant step forward in this direction, by developing a statistical test to identify particle types in a many-body interference pattern. This tool can be applied in a general scenario to assess and investigate multi-particle coherent dynamics.

  9. Vector Boson Scattering at ATLAS

    CERN Document Server

    Ozcan, V E

    2009-01-01

    While the Higgs model is the best studied scenario of electroweak symmetry breaking, there is no fundamental reason for the physics responsible for the symmetry breaking to be weakly-coupled. Many alternatives exist, predicting highly model-dependent signatures. By measuring the cross-section for the W and Z scattering at the LHC, it will be possible to obtain model-independent evidence for strong symmetry breaking or to constrain these various models. ATLAS Collaboration has recently performed a realistic simulation of this process and its backgrounds, which takes into account the detector effects and has developed new jet-analysis techniques for identifying vector bosons within the immense QCD backgrounds expected at the LHC. These techniques and the prospects for measuring the scattering signal will be presented.

  10. Weak gauge boson radiation in parton showers

    International Nuclear Information System (INIS)

    The emission of W and Z gauge bosons off quarks is included in a traditional QCD + QED shower. The unitarity of the shower algorithm links the real radiation of the weak gauge bosons to the negative weak virtual corrections. The shower evolution process leads to a competition between QCD, QED and weak radiation, and allows for W and Z boson production inside jets. Various effects on LHC physics are studied, both at low and high transverse momenta, and effects at higher-energy hadron colliders are outlined

  11. Masses of Higgs bosons in supersymmetric theories

    International Nuclear Information System (INIS)

    A simple method for Higgs boson mass calculation in the MSSM and in its minimal extension, the so-called next-to-minimal supersymmetric standard model (NMSSM), is suggested. The approach is based on the hierarchic structure of the mass matrix. Such matrices are obtained within the framework of MSSM and NMSSM. The simple analytical expression for Higgs boson spectrum in both these models are obtained. It was shown that the mass of the lightest Higgs boson in the NMSSM can be essentially lighter than its upper bound

  12. Improved effective vector boson approximation revisited

    CERN Document Server

    Bernreuther, Werner

    2015-01-01

    We reexamine the improved effective vector boson approximation which is based on two-vector-boson luminosities $\\mathrm{\\mathbf{L}}_{\\rm pol}$ for the computation of weak gauge-boson hard scattering subprocesses $V_1 V_2\\to {\\cal W}$ in high-energy hadron-hadron or $e^-e^+$ collisions. We calculate these luminosities for the nine combinations of the transverse and longitudinal polarizations of $V_1$ and $V_2$. The quality of this approach is investigated for the reactions $e^-e^+ \\to W^- W^+ \

  13. Bosonic thermoelectric transport and breakdown of universality

    International Nuclear Information System (INIS)

    We discuss the general principles of transport in normal phase atomic gases, comparing Bose and Fermi systems. Our study shows that two-dimensional bosonic transport is non-universal with respect to different dissipation mechanisms. Near the superfluid transition temperature Tc, a striking similarity between the fermionic and bosonic transport emerges because super-conducting (fluid) fluctuation transport for Fermi gases is dominated by the bosonic, Cooper pair component. As in fluctuation theory, one finds that the Seebeck coefficient changes sign at Tc and the Lorenz number approaches zero at Tc. Our findings appear quantitatively consistent with recent Bose gas experiments. (paper)

  14. An enigma called the Higgs boson

    International Nuclear Information System (INIS)

    The search for the Higgs boson, the missing pillar of the currently prevailing theory of weak and electromagnetic interactions, is a prime goal of the Large Hadron Collider (LHC) experiment. We review the circumstances, based on which our expectation of the existence of the Higgs boson has grown, how it is expected to be seen at the LHC, and where we stand in the drop of the presently available data. Moreover, we touch upon the fact that the very existence of the Higgs boson as an elementary particle provides a strong hint on possible new laws of physics. (author)

  15. Mapping the genuine bosonic quartic couplings

    CERN Document Server

    Eboli, O J P

    2016-01-01

    The larger center-of-mass energy of the Large Hadron Collider Run 2 opens up the possibility of a more detailed study of the quartic vertices of the electroweak gauge bosons. Our goal in this work is to classify all operators possessing quartic interactions among the electroweak gauge bosons that do not exhibit triple gauge-boson vertices associated to them. We obtain all relevant operators in the non-linear and linear realizations of the $SU(2)_L \\otimes U(1)_Y$ gauge symmetry.

  16. A light Higgs Boson would invite Supersymmmetry

    CERN Document Server

    Ellis, Jonathan Richard; Ellis, John; Ross, Douglas

    2001-01-01

    If the Higgs boson weighs about 115 GeV, the effective potential of the Standard Model becomes unstable above a scale of about 10^6 GeV. This instability may be rectified only by new bosonic particles such as stop squarks. However, avoiding the instability requires fine-tuning of the model couplings, in particular if the theory is not to become non-perturbative before the Planck scale. Such fine-tuning is automatic in a supersymmetric model, but is lost if there are no Higgsinos. A light Higgs boson would be prima facie evidence for supersymmetry in the top-quark and Higgs sectors.

  17. The Goldstone boson equivalence theorem with fermions

    OpenAIRE

    Durand, Loyal; Riesselmann, Kurt

    1995-01-01

    The calculation of the leading electroweak corrections to physical transition matrix elements in powers of $M_H^2/v^2$ can be greatly simplified in the limit $M_H^2\\gg M_W^2,\\, M_Z^2$ through the use of the Goldstone boson equivalence theorem. This theorem allows the vector bosons $W^\\pm$ and $Z$ to be replaced by the associated scalar Goldstone bosons $w^\\pm$, $z$ which appear in the symmetry breaking sector of the Standard Model in the limit of vanishing gauge couplings. In the present pape...

  18. Quantum mechanical formalism of particle beam optics

    OpenAIRE

    Khan, Sameen Ahmed

    2001-01-01

    A general procedure for construction of the formalism of quantum beam optics for any particle is reviewed. The quantum formalism of spin-1/2 particle beam optics is presented starting {\\em ab initio} with the Dirac equation. As an example of application the case of normal magnetic quadrupole lens is discussed. In the classical limit the quantum formalism leads to the well-known Lie algebraic formalism of classical particle beam optics.

  19. A Survey of Formal Languages for Contracts

    DEFF Research Database (Denmark)

    Hvitved, Tom

    In this short paper we present the current status on formal languages and models for contracts. By a formal model is meant an unambiguous and rigorous representation of contracts, in order to enable their automatic validation, execution, and analysis — activates that are collectively referred to as...... contract lifecycle management (CLM). We present a set of formalism requirements, which represent features that any ideal contract model should support, based on which we present a comparative survey of existing contract formalisms....

  20. Formalizing Preference Utilitarianism in Physical World Models

    OpenAIRE

    Oesterheld, Caspar

    2015-01-01

    Most ethical work is done at a low level of formality. This makes practical moral questions inaccessible to formal and natural sciences and can lead to misunderstandings in ethical discussion. In this paper, we use Bayesian inference to introduce a formalization of preference utilitarianism in physical world models, specifically cellular automata. Even though our formalization is not immediately applicable, it is a first step in providing ethics and ultimately the question of how to "make the...

  1. Searches for heavy Higgs bosons decaying to light Higgs bosons with a mass of 125 GeV

    CERN Document Server

    Lane, Rebecca

    2015-01-01

    Searches for Higgs bosons decaying to a pair of Higgs bosons (hh or hA) or for a Higgs boson decaying to Zh/ZA are presented. Different analyses involving Higgs boson decays into bottom-quarks, tau pairs, and diphotons will be summarized in this talk.

  2. Pseudospin S = 1 formalism and skyrmion-like excitations in the three-body constrained extended Bose–Hubbard model

    Energy Technology Data Exchange (ETDEWEB)

    Moskvin, A. S., E-mail: alexander.moskvin@urfu.ru [Ural Federal University (Russian Federation)

    2015-09-15

    We discuss the most prominent and intensively studied S = 1 pseudospin formalism for the extended bosonic Hubbard model (EBHM) with the on-site Hilbert space truncated to the three lowest occupation states n = 0, 1, 2. The EBHM Hamiltonian is a paradigmatic model for the highly topical field of ultracold gases in optical lattices. The generalized non-Heisenberg effective pseudospin Hamiltonian does provide a deep link with a boson system and a physically clear description of “the myriad of phases,” from uniform Mott insulating phases and density waves to two types of superfluids and supersolids. We argue that the 2D pseudospin system is prone to a topological phase separation and focus on several types of unconventional skyrmion-like topological structures in 2D boson systems, which have not been analyzed until now. The structures are characterized by a complicated interplay of insulating and two superfluid phases with a single- boson and two-boson condensation, respectively.

  3. Effects of Colombia's Social Protection System on Workers' Choice between Formal and Informal Employment

    OpenAIRE

    Camacho, Adriana; Conover, Emily; Hoyos, Alejandro

    2013-01-01

    This paper examines whether the Colombian government's expansion of social programs in the early 1990s, particularly the publicly provided health insurance, discouraged formal employment. Using household survey data and variation across municipalities in the onset of interviews for the SISBEN, the instrument used to identify beneficiaries for public health insurance, it shows robust and co...

  4. Covariant collective coordinates method in path integral formalism: application to quantum gravity on classical background

    International Nuclear Information System (INIS)

    In this paper the problem of quantization of the free gravitational field on classical background (the exact solutions of Einstein equations) is considered. The Bogoliubov group coordinates method in path integral formalism is developed. This approach makes it possible to take carefully into account the conservation laws alongside with the perturbation theory expansion

  5. New and More General Rational Formal Solutions to (2+1)-Dimensional Toda System

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    With the aid of computerized symbolic computation and Riccati equation rational expansion approach, some new and more general rational formal solutions to (2+1)-dimensional Toda system are obtained. The method used here can also be applied to solve other nonlinear differential-difference equation or equations.

  6. Search for nonminimal neutral Higgs bosons from Z-boson decays

    International Nuclear Information System (INIS)

    Using the Mark II detector at the SLAC Linear Collider, we search for decays of the Z boson to a pair of nonminimal Higgs bosons (Z→Hs0Hp0), where one of them is relatively light (approx-lt 10 GeV). We find no evidence for these decays and we obtain limits on the ZHs0Hp0 coupling as a function of the Higgs-boson masses

  7. Research on Higgs bosons by positron-electron collisions

    International Nuclear Information System (INIS)

    The experimental results obtained at LEP concerning Higgs bosons research are discussed. The existence of the Higgs bosons, from the Standard Model principles, is reviewed. The investigations on charged and neutral Higgs bosons are discussed taking into account a two-doublets model. The investigations show: that the Higgs bosons cannot be found between zero and 41 GeV, and that the Higgs boson mass is approximately 40 GeV

  8. Formal Connections for families of Star Products

    DEFF Research Database (Denmark)

    Ellegaard Andersen, Jørgen; Masulli, Paolo; Schaetz, Florian

    We define the notion of a formal connection for a smooth family of star products with fixed underlying symplectic structure. Such a formal connection allows one to relate star products at different points in the family. This generalizes the formal Hitchin connection introduced by the first author...

  9. Formal Testing of Correspondence Carrying Software

    NARCIS (Netherlands)

    Bujorianu, M.C.; Bujorianu, L.M.; Maharaj, S.

    2008-01-01

    Nowadays formal software development is characterised by use of multitude formal specification languages. Test case generation from formal specifications depends in general on a specific language, and, moreover, there are competing methods for each language. There is a need for a generic approach to

  10. Formalizing the concept phase of product development

    NARCIS (Netherlands)

    Schuts, M.; Hooman, J.

    2015-01-01

    We discuss the use of formal techniques to improve the concept phase of product realisation. As an industrial application, a new concept of interventional X-ray systems has been formalized, using model checking techniques and the simulation of formal models. cop. Springer International Publishing Sw

  11. Fuzzy Set Approximations in Fuzzy Formal Contexts

    Institute of Scientific and Technical Information of China (English)

    Mingwen Shao; Shiqing Fan

    2006-01-01

    In this paper, a kind of multi-level formal concept is introduced. Based on the proposed multi-level formal concept, we present a pair of rough fuzzy set approximations within fuzzy formal contexts. By the proposed rough fuzzy set approximations, we can approximate a fuzzy set according to different precision level. We discuss the properties of the proposed approximation operators in detail.

  12. Multipole expansions in magnetostatics

    International Nuclear Information System (INIS)

    Multipole expansions of the magnetic field of a spatially restricted system of stationary currents and those for the potential function of such currents in an external magnetic field are studied using angular momentum algebraic techniques. It is found that the expansion for the magnetic induction vector is made identical to that for the electric field strength of a neutral system of charges by substituting electric for magnetic multipole moments. The toroidal part of the multipole expansion for the magnetic field vector potential can, due to its potential nature, be omitted in the static case. Also, the potential function of a system of currents in an external magnetic field and the potential energy of a neutral system of charges in an external electric field have identical multipole expansions. For axisymmetric systems, the expressions for the field and those for the potential energy of electric and magnetic multipoles are reduced to simple forms, with symmetry axis orientation dependence separated out. (methodological notes)

  13. Multipole expansions in magnetostatics

    Energy Technology Data Exchange (ETDEWEB)

    Agre, Mark Ya [National University of ' Kyiv-Mohyla Academy' , Kyiv (Ukraine)

    2011-02-28

    Multipole expansions of the magnetic field of a spatially restricted system of stationary currents and those for the potential function of such currents in an external magnetic field are studied using angular momentum algebraic techniques. It is found that the expansion for the magnetic induction vector is made identical to that for the electric field strength of a neutral system of charges by substituting electric for magnetic multipole moments. The toroidal part of the multipole expansion for the magnetic field vector potential can, due to its potential nature, be omitted in the static case. Also, the potential function of a system of currents in an external magnetic field and the potential energy of a neutral system of charges in an external electric field have identical multipole expansions. For axisymmetric systems, the expressions for the field and those for the potential energy of electric and magnetic multipoles are reduced to simple forms, with symmetry axis orientation dependence separated out. (methodological notes)

  14. Weakly relativistic plasma expansion

    Energy Technology Data Exchange (ETDEWEB)

    Fermous, Rachid, E-mail: rfermous@usthb.dz; Djebli, Mourad, E-mail: mdjebli@usthb.dz [Theoretical Physics Laboratory, Faculty of Physics, USTHB, B.P. 32 Bab-Ezzouar, 16079 Algiers (Algeria)

    2015-04-15

    Plasma expansion is an important physical process that takes place in laser interactions with solid targets. Within a self-similar model for the hydrodynamical multi-fluid equations, we investigated the expansion of both dense and under-dense plasmas. The weakly relativistic electrons are produced by ultra-intense laser pulses, while ions are supposed to be in a non-relativistic regime. Numerical investigations have shown that relativistic effects are important for under-dense plasma and are characterized by a finite ion front velocity. Dense plasma expansion is found to be governed mainly by quantum contributions in the fluid equations that originate from the degenerate pressure in addition to the nonlinear contributions from exchange and correlation potentials. The quantum degeneracy parameter profile provides clues to set the limit between under-dense and dense relativistic plasma expansions at a given density and temperature.

  15. Formal Proofs for Nonlinear Optimization

    Directory of Open Access Journals (Sweden)

    Victor Magron

    2015-01-01

    Full Text Available We present a formally verified global optimization framework. Given a semialgebraic or transcendental function f and a compact semialgebraic domain K, we use the nonlinear maxplus template approximation algorithm to provide a certified lower bound of f over K.This method allows to bound in a modular way some of the constituents of f by suprema of quadratic forms with a well chosen curvature. Thus, we reduce the initial goal to a hierarchy of semialgebraic optimization problems, solved by sums of squares relaxations. Our implementation tool interleaves  semialgebraic approximations with sums of squares witnesses to form certificates. It is interfaced with Coq and thus benefits from the trusted arithmetic available inside the proof assistant. This feature is used to produce, from the certificates, both valid underestimators and lower bounds for each approximated constituent.The application range for such a tool is widespread; for instance Hales' proof of Kepler's conjecture yields thousands of multivariate transcendental inequalities. We illustrate the performance of our formal framework on some of these inequalities as well as on examples from the global optimization literature.

  16. A new type of massive spin-one boson: And its relation with Maxwell equations

    International Nuclear Information System (INIS)

    First, the author showed that in the (1, 0) circle-plus (0, 1) representation space there exist not one but two theories for charged particles. In the Weinberg construct, the boson and its antiboson carry same relative intrinsic parity, whereas in the author's construct the relative intrinsic parities of the boson and its antiboson are opposite. These results originate from the commutativity of the operations of Charge conjugation and Parity in Weinberg's theory, and from the anti-commutativity of the operations of Charge conjugation and Parity in the author's theory. The author thus claims that he has constructed a first non-trivial quantum theory of fields for the Wigner-type particles. Second, the massless limit of both theories seems formally identical and suggests a fundamental modification of Maxwell equations. At its simplest level, the modification to Maxwell equations enters via additional boundary condition(s)

  17. Associated Production of Heavy Quarkonia and Electroweak Bosons at Present and Future Colliders

    CERN Document Server

    Kniehl, Bernd A; Zwirner, Lennart; Kniehl, Bernd A.; Palisoc, Caesar P.; Zwirner, Lennart

    2002-01-01

    We investigate the associated production of heavy quarkonia, with angular-momentum quantum numbers ^{2S+1}L_J = ^1S_0, ^3S_1, ^1P_1, ^3P_J (J = 0, 1, 2), and photons, Z bosons, and W bosons in photon-photon, photon-hadron, and hadron-hadron collisions within the factorization formalism of nonrelativistic quantum chromodynamics providing all contributing partonic cross sections in analytic form. In the case of photoproduction, we also include the resolved-photon contributions. We present numerical results for the processes involving J/psi and chi_{cJ} mesons appropriate for the Fermilab Tevatron, CERN LHC, DESY TESLA, operated in the e^+ e^- and gamma gamma modes, and DESY THERA.

  18. Weak boson production via vector-boson fusion rate at NLO matched with Powheg

    International Nuclear Information System (INIS)

    The production of weak vector-bosons in association with two jets is an important background to Higgs-boson searches in vector-Boson fusion (VBF) at the LHC. In order to make reliable predictions, the combination of fixed-order NLO-calculations and parton-showers is indispensable. We present the implementation of the weak boson production via VBF in the Powheg-Box. This is a first step to interface Vbfnlo, a fully flexible Monte Carlo program, with the Powheg-Box.

  19. Landau-Yang Theorem and Decays of a Z' Boson into Two Z Bosons

    OpenAIRE

    Keung, Wai-Yee; Low, Ian; Shu, Jing

    2008-01-01

    We study the decay of a Z' boson into two Z bosons by extending the Landau-Yang theorem to a parent particle decaying into two Z bosons. For a spin-1 parent the theorem predicts: 1) there are only two possible couplings and 2) the normalized differential cross-section depends on kinematics only through a phase shift in the azimuthal angle between the two decay planes of the Z boson. When the parent is a Z' the two possible couplings are anomaly-induced and CP-violating, respectively. At the L...

  20. The future of the Higgs boson

    International Nuclear Information System (INIS)

    Experimentalists and theorists are still celebrating the Nobel-worthy discovery of the Higgs boson that was announced in July 2012 at CERN’s Large Hadron Collider. Now they are working on the profound implications of that discovery

  1. Bosonic superconformal Toda model and dressing transformation

    International Nuclear Information System (INIS)

    The authors show the dressing transformations of the basic field and the classical chiral operators in the Bosonic Superconformal Toda model. After quantization, The related quantum algebra is obtained

  2. Acquiring a taste for the Higgs boson

    CERN Multimedia

    Caroline Duc

    2012-01-01

    Before CERN's scientists had even announced the discovery of the Higgs boson, others were already attributing some interesting characteristics to it: flavoursome, sparkling and liquid...   The artisan brewery Hopfenstark in Quebec launched its new "Higgs boson" beer in November 2010. Ever since, it has been intriguing enthusiasts with its unique taste explosion. The boson was a source of inspiration for brewer Frédéric Cormier, the Hopfenstark brewery's owner, who is a big fan of science programmes. "I returned from a trip to Europe in 2010 with the idea for a new beer that would be unlike any other," he explains. "I was always reading and hearing about CERN's particle accelerator in the media, so I did some research on the famous Higgs boson and decided to give my new creation the same name." For Frédéric Cormier, it's important that the names of his beers refle...

  3. A Historical Profile of the Higgs Boson

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, John; Gaillard, Mary K.; Nanopoulos, Dimitri V.

    2012-01-31

    The Higgs boson was postulated in 1964, and phenomenological studies of its possible production and decays started in the early 1970s, followed by studies of its possible productionin e{sup +} e{sup -}, {anti p}p and pp collisions, in particular. Until recently, the most sensitive searches for the Higgs boson were at LEP between 1989 and 2000, which have been complemented bysearches at the Fermilab Tevatron. The LHC has recently entered the hunt, excluding a Higgs boson over a large range of masses and revealing a tantalizing hint in the range 119 to125 GeV, and there are good prospects that the existence or otherwise of the Higgs boson will soon be established. One of the most attractive possibilities is that the Higgs bosonis accompanied by supersymmetry, though composite options have yet to be excluded. This article reviews some of the key historical developments in Higgs physics over the past half-century.

  4. Quantum geometry of bosonic strings - revisited

    International Nuclear Information System (INIS)

    We review the original paper by A.M. Polyakov (Quantum Geometry of Bosonic Strings) with corrections and improvements the concepts exposed there and following as closely as possible to the original A.M. Polyakov's paper. (author)

  5. Microscopic boson approach to nuclear collective motion

    International Nuclear Information System (INIS)

    A quantum mechanical approach to the maximally decoupled nuclear collective motion is proposed. The essential idea is to transcribe the original shell-model Hamiltonian in terms of boson operators, then to isolate the collective one-boson eigenstates of the mapped Hamiltonian and to perform a canonical transformation which eliminates (up to the two-body terms) the coupling between the collective and noncollective bosons. Unphysical states arising due to the violtion of the Pauli principle in the boson space are identified and removed within a suitable approximation. The method is applied to study the low-lying collective states of nuclei which are successfully described by the exactly solvable multilevel pairing Hamiltonian (Sn, Ni, Pb). 75 refs.; 8 figs

  6. The pomeron in closed bosonic string theory

    CERN Document Server

    Fazio, A R

    2010-01-01

    We review the features of the pomeron in the S-matrix theory and in quantum field theory. We extend those general properties to the pomeron of closed bosonic string theory in a Minkowskian background. We compute the couplings of the pomeron to the lowest mass levels of closed bosonic string states in flat space. We recognize the deviation from the linearity of the Regge trajectories in a five dimensional anti De Sitter background.

  7. Fermion boson metamorphosis in field theory

    International Nuclear Information System (INIS)

    In two-dimensional field theories many features are especially transparent if the Fermi fields are represented by non-local expressions of the Bose fields. Such a procedure is known as boson representation. Bilinear quantities appear in the Lagrangian of a fermion theory transform, however, as simple local expressions of the bosons so that the resulting theory may be written as a theory of bosons. Conversely, a theory of bosons may be transformed into an equivalent theory of fermions. Together they provide a basis for generating many interesting equivalences between theories of different types. In the present work a consistent scheme for constructing a canonical Fermi field in terms of a real scalar field is developed and such a procedure is valid and consistent with the tenets of quantum field theory is verified. A boson formulation offers a unifying theme in understanding the structure of many theories. This is illustrated by the boson formulation of a multifermion theory with chiral and internal symmetries. The nature of dynamical generation of mass when the theory undergoes boson transmutation and the preservation of continuous chiral symmetry in the massive case are examined. The dynamics of the system depends to a great extent on the specific number of fermions and different models of the same system can have very different properties. Many unusual symmetries of the fermion theory, such as hidden symmetry, duality and triality symmetries, are only manifest in the boson formulation. The underlying connections between some models with U(N) internal symmetry and another class of fermion models built with Majorana fermions which have O(2N) internal symmetry are uncovered

  8. Vector-boson-induced neutrino mass

    International Nuclear Information System (INIS)

    One-loop radiative Majorana neutrino masses through the exchange of scalars have been considered for many years. We show for the first time how such a one-loop mass is also possible through the exchange of vector gauge bosons. It is based on a simple variation of a recently proposed SU(2)N extension of the Standard Model, where a vector boson is a candidate for the dark matter of the Universe.

  9. Study of single W bosons at JLC

    Energy Technology Data Exchange (ETDEWEB)

    Arogancia, Dennis C.; Sanchez, Allister Levi C.; Magallanes, Jingle B.; Gooc, Hermogenes C.; Bacala, Angelina M. [Mindanao State Univ., Dept. of Physics, Iligan (Philippines); Fujii, Keisuke; Miyamoto, Akiya [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan)

    2001-06-01

    Single W bosons are studied through computer simulation using the process e{sup +}e{sup -} {yields} e{sup +}{nu}{sub e}W{sup -} where it decays into two hadronic jets. This study focuses of the measurement of W boson mass with and without beamstrahlung and initial state radiation (ISR) effects. The JLC Study Framework (JSF) is employed for this purpose. The center-of-mass energy is set at 500 GeV. (author)

  10. Higgs bosons in the simplest SUSY models

    OpenAIRE

    Nevzorov, R. B.; Ter-Martirosyan, K. A.; Trusov, M.A.

    2001-01-01

    Nowadays in the MSSM the moderate values of $\\tan\\beta$ are almost excluded by LEP II lower bound on the lightest Higgs boson mass. In the Next-to-Minimal Supersymmetric Standard Model the theoretical upper bound on it increases and reaches maximal value in the strong Yukawa coupling limit when all solutions of renormalization group equations are concentrated near the quasi-fixed point. For calculation of Higgs boson spectrum the perturbation theory method can be applied. We investigate the p...

  11. Unconventional quantum phases of lattice bosonic mixtures

    OpenAIRE

    Buonsante, P.; Giampaolo, S. M.; Illuminati, F.; Penna, V; Vezzani, A.

    2008-01-01

    We consider strongly interacting boson-boson mixtures on one-dimensional lattices and, by adopting a qualitative mean-field approach, investigate their quantum phases as the interspecies repulsion is increased. In particular, we analyze the low-energy "quantum emulsion" metastable states occurring at large values of the interspecies interaction, which are expected to prevent the system from reaching its true ground state. We argue a significant decrease in the visibility of the time-of-flight...

  12. Deformed Bosons: Combinatorics of Normal Ordering

    CERN Document Server

    Blasiak, P; Penson, K A; Solomon, A I

    2004-01-01

    We solve the normal ordering problem for (A* A)^n where A* (resp. A) are one mode deformed bosonic creation (resp. annihilation) operators satisfying [A,A*]=[N+1]-[N]. The solution generalizes results known for canonical and q-bosons. It involves combinatorial polynomials in the number operator N for which the generating functions and explicit expressions are found. Simple deformations provide examples of the method.

  13. Electroweak Precision Data and New Gauge Bosons

    OpenAIRE

    Erler, Jens

    2009-01-01

    I review constraints on the Standard Model (SM) Higgs boson from high energy electroweak (EW) precision data. The same data set also strongly limits various mixing effects of hypothetical extra neutral gauge bosons (Z') with the ordinary Z. I also discuss low energy precision measurements which are sensitive to other aspects of Z' physics, such as the direct exchange amplitude and the flavor or CP violating sectors.

  14. Precision Probes of a Leptophobic Z' Boson

    OpenAIRE

    Buckley, Matthew R.; Ramsey-Musolf, Michael J.

    2012-01-01

    Extensions of the Standard Model that contain leptophobic Z' gauge bosons are theoretically interesting but difficult to probe directly in high-energy hadron colliders. However, precision measurements of Standard Model neutral current processes can provide powerful indirect tests. We demonstrate that parity-violating deep inelastic scattering of polarized electrons off of deuterium offer a unique probe leptophobic Z' bosons with axial quark couplings and masses above 100 GeV. In addition to c...

  15. Microscopic foundation of the interacting boson model

    International Nuclear Information System (INIS)

    A microscopic foundation of the interacting boson model is described. The importance of monopole and quadrupole pairs of nucleons is emphasized. Those pairs are mapped onto the s and d bosons. It is shown that this mapping provides a good approximation in vibrational and transitional nuclei. In appendix, it is shown that the monopole pair of electrons plays possibly an important role in metal clusters. (orig.)

  16. Vector bosons in the expanding universe

    International Nuclear Information System (INIS)

    We exactly solve the relativistic wave equation for vector bosons in the expanding universe and show that the current of the vector bosons in this background is rapidly oscillating in early time. Additionally, we derive the solutions of the Proca equation from the solutions of the Duffin-Kemmer-Petiau (DKP) equations in the same background and obtain the massless-particle, photon, solutions by taking the m2→0 limit of these solutions. (orig.)

  17. SU(N) Irreducible Schwinger Bosons

    OpenAIRE

    Mathur, Manu; Raychowdhury, Indrakshi; Anishetty, Ramesh

    2010-01-01

    We construct SU(N) irreducible Schwinger bosons satisfying certain U(N-1) constraints which implement the symmetries of SU(N) Young tableaues. As a result all SU(N) irreducible representations are simple monomials of $(N-1)$ types of SU(N) irreducible Schwinger bosons. Further, we show that these representations are free of multiplicity problems. Thus all SU(N) representations are made as simple as SU(2).

  18. Supersymmetry search via gauge boson fusion

    Indian Academy of Sciences (India)

    Anindya Datta

    2003-02-01

    We propose a novel method for the search of supersymmetry, especially for the electroweak gauginos at the large hadron collider (LHC). Gauge boson fusion technique was shown to be useful for heavy and intermediate mass Higgs bosons. In this article, we have shown that this method can also be applied to find the signals of EW gauginos in supersymmetric theories where the canonical search strategies for these particles fail.

  19. A Comparison of Participation Patterns in Selected Formal, Non-Formal, and Informal Online Learning Environments

    Science.gov (United States)

    Schwier, Richard A.; Seaton, J. X.

    2013-01-01

    Does learner participation vary depending on the learning context? Are there characteristic features of participation evident in formal, non-formal, and informal online learning environments? Six online learning environments were chosen as epitomes of formal, non-formal, and informal learning contexts and compared. Transcripts of online…

  20. Resonant state expansions

    International Nuclear Information System (INIS)

    The completeness properties of the discrete set of bound state, virtual states and resonances characterizing the system of a single nonrelativistic particle moving in a central cutoff potential is investigated. From a completeness relation in terms of these discrete states and complex scattering states one can derive several Resonant State Expansions (RSE). It is interesting to obtain purely discrete expansion which, if valid, would significantly simplify the treatment of the continuum. Such expansions can be derived using Mittag-Leffler (ML) theory for a cutoff potential and it would be nice to see if one can obtain the same expansions starting from an eigenfunction theory that is not restricted to a finite sphere. The RSE of Greens functions is especially important, e.g. in the continuum RPA (CRPA) method of treating giant resonances in nuclear physics. The convergence of RSE is studied in simple cases using square well wavefunctions in order to achieve high numerical accuracy. Several expansions can be derived from each other by using the theory of analytic functions and one can the see how to obtain a natural discretization of the continuum. Since the resonance wavefunctions are oscillating with an exponentially increasing amplitude, and therefore have to be interpreted through some regularization procedure, every statement made about quantities involving such states is checked by numerical calculations.Realistic nuclear wavefunctions, generated by a Wood-Saxon potential, are used to test also the usefulness of RSE in a realistic nuclear calculation. There are some fundamental differences between different symmetries of the integral contour that defines the continuum in RSE. One kind of symmetry is necessary to have an expansion of the unity operator that is idempotent. Another symmetry must be used if we want purely discrete expansions. These are found to be of the same form as given by ML. (29 refs.)

  1. Formulation of a unified method for low- and high-energy expansions in the analysis of reflection coefficients for one-dimensional Schr\\"odinger equation

    OpenAIRE

    Miyazawa, Toru

    2015-01-01

    We study low-energy expansion and high-energy expansion of reflection coefficients for one-dimensional Schr\\"odinger equation, from which expansions of the Green function can be obtained. Making use of the equivalent Fokker-Planck equation, we develop a generalized formulation of a method for deriving these expansions in a unified manner. In this formalism, the underlying algebraic structure of the problem can be clearly understood, and the basic formulas necessary for the expansions can be d...

  2. Formal Aspects of Grid Brokering

    CERN Document Server

    Kertész, Attila; 10.4204/EPTCS.14.2

    2009-01-01

    Coordination in distributed environments, like Grids, involves selecting the most appropriate services, resources or compositions to carry out the planned activities. Such functionalities appear at various levels of the infrastructure and in various means forming a blurry domain, where it is hard to see how the participating components are related and what their relevant properties are. In this paper we focus on a subset of these problems: resource brokering in Grid middleware. This paper aims at establishing a semantical model for brokering and related activities by defining brokering agents at three levels of the Grid middleware for resource, host and broker selection. The main contribution of this paper is the definition and decomposition of different brokering components in Grids by providing a formal model using Abstract State Machines.

  3. Formal analysis of physical theories

    International Nuclear Information System (INIS)

    The rules of inference that are made use of in formalization are considered. It is maintained that a physical law represents the universal assertion of a probability, and not the assessment of the probability of a universal assertion. The precision of the apparatus used to collect the experimental evidence is introduced as an essential part of the theoretical structure of physics. This approach allows the author to define the concept of truth in a satisfactory way, abandoning the unacceptable notion of approximate truth. It is shown that a considerable amount of light can be shed on a number of much debated problems arising in the logic of quantum mechanics. It is stressed that the deductive structure of quantum theory seems to be essentially founded on a kind of mixture of different logics. Two different concepts of truth are distinguished within quantum theory, an empirical truth and quantum-logical truth. (Auth.)

  4. Charging transient in polyvinyl formal

    Indian Academy of Sciences (India)

    P K Khare; P L Jain; R K Pandey

    2001-08-01

    In the present paper charging and discharging transient currents in polyvinyl formal (PVF) were measured as a function of temperatures (40–80°C), poling fields (9.0 × 103–9.0 × 104 V/cm) and electrode combinations (Al–Al, Au–Al, Zn–Al, Bi–Al, Cu–Al and Ag–Al). The current–time characteristics have different values of slope lying between 0.42–0.56 and 1.42–1.63. The polarization is considered to be due to dipolar reorientation associated with structural motions and space charge relaxations due to trapping of injected charge carriers in energetically distributed traps.

  5. Neutral Supersymmetric Higgs Boson Searches

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, Stephen Luke; /Imperial Coll., London

    2009-09-01

    In some Supersymmetric extensions of the Standard Model, including the Minimal Supersymmetric Standard Model (MSSM), the coupling of Higgs bosons to b-quarks is enhanced. This enhancement makes the associated production of the Higgs with b-quarks an interesting search channel for the Higgs and Supersymmetry at D0. The identification of b-quarks, both online and offline, is essential to this search effort. This thesis describes the author's involvement in the development of both types of b-tagging and in the application of these techniques to the MSSM Higgs search. Work was carried out on the Level-3 trigger b-tagging algorithms. The impact parameter (IP) b-tagger was retuned and the effects of increased instantaneous luminosity on the tagger were studied. An extension of the IP-tagger to use the z-tracking information was developed. A new b-tagger using secondary vertices was developed and commissioned. A tool was developed to allow the use of large multi-run samples for trigger studies involving b-quarks. Offline, a neural network (NN) b-tagger was trained combining the existing offline lifetime based b-tagging tools. The efficiency and fake rate of the NN b-tagger were measured in data and MC. This b-tagger was internally reviewed and certified by the Collaboration and now provides the official b-tagging for all analyses using the Run IIa dataset at D0. A search was performed for neutral MSSM Higgs bosons decaying to a b{bar b} pair and produced in association with one or more b-quarks. Limits are set on the cross-section times the branching ratio for such a process. The limits were interpreted in various MSSM scenarios. This analysis uses the NN b-tagger and was the first to use this tool. The analysis also relies on triggers using the Level-3 IP b-tagging tool described previously. A likelihood discriminant was used to improve the analysis and a neural network was developed to cross-check this technique. The result of the analysis has been submitted to PRL

  6. Neutral Supersymmetric Higgs Boson Searches

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, Stephen Luke [Imperial College, London (United Kingdom)

    2008-07-01

    In some Supersymmetric extensions of the Standard Model, including the Minimal Supersymmetric Standard Model (MSSM), the coupling of Higgs bosons to b-quarks is enhanced. This enhancement makes the associated production of the Higgs with b-quarks an interesting search channel for the Higgs and Supersymmetry at D0. The identification of b-quarks, both online and offline, is essential to this search effort. This thesis describes the author's involvement in the development of both types of b-tagging and in the application of these techniques to the MSSM Higgs search. Work was carried out on the Level-3 trigger b-tagging algorithms. The impact parameter (IP) b-tagger was retuned and the effects of increased instantaneous luminosity on the tagger were studied. An extension of the IP-tagger to use the z-tracking information was developed. A new b-tagger using secondary vertices was developed and commissioned. A tool was developed to allow the use of large multi-run samples for trigger studies involving b-quarks. Offline, a neural network (NN) b-tagger was trained combining the existing offline lifetime based b-tagging tools. The efficiency and fake rate of the NN b-tagger were measured in data and MC. This b-tagger was internally reviewed and certified by the Collaboration and now provides the official b-tagging for all analyses using the Run IIa dataset at D0. A search was performed for neutral MSSM Higgs bosons decaying to a b{bar b} pair and produced in association with one or more b-quarks. Limits are set on the cross-section times the branching ratio for such a process. The limits were interpreted in various MSSM scenarios. This analysis uses the NN b-tagger and was the first to use this tool. The analysis also relies on triggers using the Level-3 IP b-tagging tool described previously. A likelihood discriminant was used to improve the analysis and a neural network was developed to cross-check this technique. The result of the analysis has been submitted to PRL

  7. Fermions and bosons on an atom chip

    Science.gov (United States)

    Extravour, Marcius H. T.

    Ultra-cold dilute gases of neutral atoms are attractive candidates for creating controlled mesoscopic quantum systems. In particular, quantum degenerate gases of bosonic and fermionic atoms can be used to model the correlated many-body behaviour of Bose and Fermi condensed matter systems, and to study matter wave interference and coherence. This thesis describes the experimental realization and manipulation of Bose-Einstein condensates (BECs) of 87Rb and degenerate Fermi gases (DFGs) of 40K using static and dynamic magnetic atom chip traps. Atom chips are versatile modern tools used to manipulate atomic gases. The chips consist of micrometre-scale conductors supported by a planar insulating substrate, and can be used to create confining potentials for neutral atoms tens or hundreds of micrometres from the chip surface. We demonstrate for the first time that a DFG can be produced via sympathetic cooling with a BEC using a simple single-vacuum-chamber apparatus. The large 40 K-87Rb collision rate afforded by the strongly confining atom chip potential permits rapid cooling of 40K to quantum degeneracy via sympathetic cooling with 87Rb. By studying 40K-87Rb cross-thermalization as a function of temperature, we observe the Ramsauer-Townsend reduction in the 40K-87Rb elastic scattering cross-section. We achieve DFG temperatures as low as T ≈ 0:1TF, and observe Fermi pressure in the time-of-flight expansion of the gas. This thesis also describes the radio-frequency (RF) manipulation of trapped atoms to create dressed state double-well potentials for BEC and DFG. We demonstrate for the first time that RF-dressed potentials are species-selective, permitting the formation of simultaneous 87Rb double-well and 40K single-well potentials using a 40K-87Rb mixture. We also develop tools to measure fluctuations of the relative atom number and relative phase of a dynamically split 87Rb BEC. In particular, we observe atom number fluctuations at the shot-noise level using time

  8. Microscopic foundation and geometric interpretation of the interacting-boson model

    International Nuclear Information System (INIS)

    A number of aspects of the relation between the shell model and the interacting-boson model are studied. The IBM is assumed to describe that part of the shell-model space where all states are built from selected, correlated pairs with angular momentum zero or two, which are mapped onto bosons. The goal of a microscopic derivation of IBM is to determine this subspace and to obtain the parameters that govern the dynamics in boson space. A formalism is introduced to calculate the expectation value of the hamiltonian between states containing such correlated fermion pairs. This formalism only applies to spherical nuclei, where zero-coupled pairs dominate. It is applied to the semimagic tin nuclei. Several methods are compared to determine the structure of the collective pairs in order to find a method which gives the 'best pairs'. The formalism is also applied to the mercury isotopes for which both neutrons and protons are active. In this more realistic case the above-mentioned methods to determine the pairs are also studied. The IBM-2 parameters are derived from the microscopic calculation. Group-theoretical aspects of the SU(3) limits of IBM-1 and IBM-2 are investigated. A complete decomposition for the SU(3) limits is given. Specific attention is paid to the 'triaxial-rotor' SU(3)*-limit, which is thought to describe nuclei with a triaxial shape. The SU(3)* symmetry of IBM-2 is applied in a study of the 192Os nucleus. The relation between IBM and geometrical models is discussed. (Auth.)

  9. Expansion joints for LMFBR

    International Nuclear Information System (INIS)

    This discourse recounts efforts put into the SNR-2 project; specifically the development of compensation devices. The various prototypes of these compensation devices are described and the state of the development reviewed. Large Na (sodium)-heat transfer systems require a lot of valuable space if the component lay-out does not include compensation devices. So, in order to condense the spatial requirement as much as possible, expansion joints must be integrated into the pipe system. There are two basic types to suit the purpose: axial expansion joints and angular expansion joints. The expansion joints were developed on the basis of specific design criteria whereby differentiation is made between expansion joints of small and large nominal diameter. Expansion joints for installation in the sodium-filled primary piping are equipped with safety bellows in addition to the actual working bellows. Expansion joints must be designed and mounted in a manner to completely withstand seismic forces. The design must exclude any damage to the bellows during intermittent operations, that is, when sodium is drained the bellows' folds must be completely empty; otherwise residual solidified sodium could destroy the bellows when restarting. The expansion joints must be engineered on the basis of the following design data for the secondary system of the SNR project: working pressure: 16 bar; failure mode pressure: 5 events; failure mode: 5 sec., 28.5 bar, 520 deg. C; working temperature: 520 deg. C; temperature transients: 30 deg. C/sec.; service life: 200,000 h; number of load cycles: 104; material: 1.4948 or 1.4919; layer thickness of folds: 0.5 mm; angular deflection (DN 800): +3 deg. C or; axial expansion absorption (DN 600): ±80 mm; calculation: ASME class. The bellows' development work is not handled within this scope. The bellows are supplied by leading manufacturers, and warrant highest quality. Multiple bellows were selected on the basis of maximum elasticity - a property

  10. Search for the Standard Model Higgs Boson in associated production with w boson at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Xu; /Michigan U.

    2009-11-01

    A search for the Standard Model Higgs boson in proton-antiproton collisions with center-of-mass energy 1.96 TeV at the Tevatron is presented in this dissertation. The process of interest is the associated production of W boson and Higgs boson, with the W boson decaying leptonically and the Higgs boson decaying into a pair of bottom quarks. The dataset in the analysis is accumulated by the D0 detector from April 2002 to April 2008 and corresponding to an integrated luminosity of 2.7 fb{sup -1}. The events are reconstructed and selected following the criteria of an isolated lepton, missing transverse energy and two jets. The D0 Neural Network b-jet identification algorithm is further used to discriminate b jets from light jets. A multivariate analysis combining Matrix Element and Neural Network methods is explored to improve the Higgs boson signal significance. No evidence of the Higgs boson is observed in this analysis. In consequence, an observed (expected) limit on the ratio of {sigma} (p{bar p} {yields} WH) x Br (H {yields} b{bar b}) to the Standard Model prediction is set to be 6.7 (6.4) at 95% C.L. for the Higgs boson with a mass of 115 GeV.

  11. (Super)rare decays of an extra Z' boson via Higgs boson emission

    OpenAIRE

    Kozlov, G. A.

    1999-01-01

    The phenomenological model of an extra U(1) neutral gauge Z' boson coupled to heavy quarks is presented. In particular, we discuss the probability for a light $Z_{2}$ mass eigenstate decay into a bound state composed of heavy quarks via Higgs boson emission.

  12. Search for the Standard Model Higgs Boson in associated production with w boson at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Xu [Univ. of Michigan, Ann Arbor, MI (United States)

    2009-11-01

    A search for the Standard Model Higgs boson in proton-antiproton collisions with center-of-mass energy 1.96 TeV at the Tevatron is presented in this dissertation. The process of interest is the associated production of W boson and Higgs boson, with the W boson decaying leptonically and the Higgs boson decaying into a pair of bottom quarks. The dataset in the analysis is accumulated by the D0 detector from April 2002 to April 2008 and corresponding to an integrated luminosity of 2.7 fb-1. The events are reconstructed and selected following the criteria of an isolated lepton, missing transverse energy and two jets. The D0 Neural Network b-jet identification algorithm is further used to discriminate b jets from light jets. A multivariate analysis combining Matrix Element and Neural Network methods is explored to improve the Higgs boson signal significance. No evidence of the Higgs boson is observed in this analysis. In consequence, an observed (expected) limit on the ratio of σ (p$\\bar{p}$ → WH) x Br (H → b$\\bar{b}$) to the Standard Model prediction is set to be 6.7 (6.4) at 95% C.L. for the Higgs boson with a mass of 115 GeV.

  13. Bosonization and even Grassmann variables

    International Nuclear Information System (INIS)

    They test a new approach to bosonization in relativistic field theories and many-body systems, based on the use of fermionic composites as integration variables in the Berezin integral defining the partition function of the system. The method appears promising since at zeroth order it correctly describes the propagators of the composites, which can be evaluated in a number of significant cases. Still to be established is a general procedure for deriving the free action of the composites starting from the one of the constituents. To shed light on this problem and to explore further features of the method they study a simplified version of the BCS model. In this simple case the action of the composites can indeed be obtained: whether this result can be generalized it remains however to be seen. Yet an interesting property of the wave operators appearing in the free actions of bilinear composites already emerges from the simple problem they have treated: here the wave operators do not describe any time evolution, even though they generate the right propagators. This outcome relates to the basic properties of the integrals over the even elements of a Grassmann algebra where the composites live, which entails that the propagators are no longer the inverse of the wave operators

  14. Specific heat studies in Ho–Ba–CuO superconductors: Fermionic and bosonic contributions

    Indian Academy of Sciences (India)

    Dinesh Varshney; Sanjay Shah; R K Singh

    2000-08-01

    The specific heats of superconducting HoBa2Cu3O7– (c ≅ 92 K) have been theoretically investigated in the temperature domain 70 ≤ ≤ 110 K. The bosonic (phonons) contribution to the specific heat is estimated from Debye model in the harmonic approximation for high temperature expansion ( > D/2) using the moments of the phonon density of states. The fermionic constituent as the electronic specific heat is deduced using a suitable trial function above and below c. As a next step the contribution of specific heat by charge oscillations (plasmons) are obtained. The theoretical results from bosonic and fermionic terms are then compared with the experimental results. We find that the specific heats from electronic as well as plasmon term are only a fraction of lattice specific heat and in particular, plasmons do not influence the thermal conduction significantly. The implications of the above analysis are discussed.

  15. A strictly Markovian expansion for plasma turbulence theory

    Science.gov (United States)

    Jones, F. C.

    1978-01-01

    The collision operator that appears in the equation of motion for a particle distribution function that has been averaged over an ensemble of random Hamiltonians is non-Markovian. It is non-Markovian in that it involves a propagated integral over the past history of the ensemble averaged distribution function. All formal expansions of this nonlinear collision operator to date preserve this non-Markovian character term by term yielding an integro-differential equation that must be converted to a diffusion equation by an additional approximation. In this note we derive an expansion of the collision operator that is strictly Markovian to any finite order and yields a diffusion equation as the lowest non-trivial order. The validity of this expansion is seen to be the same as that of the standard quasi-linear expansion.

  16. Search for an Invisibly Decaying Higgs Boson Produced via Vector Boson Fusion

    CERN Document Server

    AUTHOR|(SzGeCERN)661801

    This thesis presents the first search of an invisibly decaying Higgs boson produced via Vector Boson Fusion on ATLAS. The dataset used for the analysis corresponds to 20.3fb$^{-1}$ of proton-proton collisions at $\\sqrt{s} = 8$ TeV recorded at the Large Hadron Collider in 2011 and 2012. An upper bound limit is set at 95% confidence level on the invisible branching fraction of the Higgs Boson. A limit of 28% is observed (34% expected) and interpreted using the Higgs portal model to set a limit on the dark matter-nucleon cross section. The unique jet final state created by Vector Boson Fusion provides a stronger signal to background ratio than other invisibly decaying Higgs channels. The Vector Boson Fusion analysis presented resulted in the strongest constraint on dark matter production set by a hadron collider.

  17. Boson mapping and the microscopic collective nuclear Hamiltonian

    International Nuclear Information System (INIS)

    Starting with the mapping of the quadrupole collective states in the fermion space onto the boson space, the fermion nuclear problem is transformed into the boson one. The boson images of the bifermion operators and of the fermion Hamiltonian are found. Recurrence relations are used to obtain approximately the norm matrix which appears in the boson-fermion mapping. The resulting boson Hamiltonian contains terms which go beyond the ordinary SU(6) symmetry Hamiltonian of the interacting boson model. Calculations, however, suggest that on the phenomenological level the differences between the mapped Hamiltonian and the SU(6) Hamiltonian are not too important. 18 refs.; 2 figs

  18. Electroweak production of single vector bosons, vector boson scattering and triple gauge-boson production with the ATLAS detector

    CERN Document Server

    Gumpert, Christian; The ATLAS collaboration

    2016-01-01

    The production of single Z bosons with two jets at high invariant mass has been studied by the ATLAS collaboration in detail using data corresponding to 20.3 /fb at a centre-of-mass energy of 8 TeV. Integrated and differential cross sections are measured in many different phase space regions with varying degree of sensitivity to the electroweak production in vector boson fusion. The cross section for the electroweak production has been extracted for both integrated and for the first time differential distributions. The results have also been used to derive limits on anomalous triple gauge couplings. Vector-boson scattering processes provide a unique way to probe the mechanism of electroweak symmetry breaking. Similar physics can be probed by studying the production of three gauge bosons. The results can also be used for a model-independent search for new physics at the TeV scale via anomalous quartic gauge couplings. The ATLAS collaboration has studied vector boson scattering in final states with two gauge bo...

  19. Chiral symmetry breaking and quark confinement in the nilpotency expansion of QCD

    CERN Document Server

    Caracciolo, Sergio

    2010-01-01

    We apply to lattice QCD a bosonization method previously developed in which dynamical bosons are generated by time-dependent Bogoliubov transformations. The transformed action can be studied by an expansion in the inverse of the nilpotency index, which is the number of fermionic states in the structure function of composite bosons. When this number diverges the model is solved by the saddle point method which has a variational interpretation. We give a stationary covariant solution for a background matter field whose fluctuations describe mesons. In the saddle point approximations live fermionic quasiparticles with quark quantum numbers which are confined, in the sense that they propagate only in pointlike color singlets. Conditions for chiral symmetry breaking are determined, to be studied numerically, and a derivation of mesons-nucleons action is outlined.

  20. Cycle expansions: From maps to turbulence

    Science.gov (United States)

    Lan, Y.

    2010-03-01

    We present a derivation, a physical explanation and applications of cycle expansions in different dynamical systems, ranging from simple one-dimensional maps to turbulence in fluids. Cycle expansion is a newly devised powerful tool for computing averages of physical observables in nonlinear chaotic systems which combines many innovative ideas developed in dynamical systems, such as hyperbolicity, invariant manifolds, symbolic dynamics, measure theory and thermodynamic formalism. The concept of cycle expansion has a deep root in theoretical physics, bearing a close analogy to cumulant expansion in statistical physics and effective action functional in quantum field theory, the essence of which is to represent a physical system in a hierarchical way by utilizing certain multiplicative structures such that the dominant parts of physical observables are captured by compact, maneuverable objects while minor detailed variations are described by objects with a larger space and time scale. The technique has been successfully applied to many low-dimensional dynamical systems and much effort has recently been made to extend its use to spatially extended systems. For one-dimensional systems such as the Kuramoto-Sivashinsky equation, the method turns out to be very effective while for more complex real-world systems including the Navier-Stokes equation, the method is only starting to yield its first fruits and much more work is needed to enable practical computations. However, the experience and knowledge accumulated so far is already very useful to a large set of research problems. Several such applications are briefly described in what follows. As more research effort is devoted to the study of complex dynamics of nonlinear systems, cycle expansion will undergo a fast development and find wide applications.

  1. Measurement-feedback formalism meets information reservoirs

    Science.gov (United States)

    Shiraishi, Naoto; Matsumoto, Takumi; Sagawa, Takahiro

    2016-01-01

    There have been two distinct formalisms of thermodynamics of information: one is the measurement-feedback formalism, which concerns bipartite systems with measurement and feedback processes, and the other is the information reservoir formalism, which considers bit sequences as a thermodynamic fuel. In this paper, we derive a second-law-like inequality by applying the measurement-feedback formalism to information reservoirs, which provides a stronger bound of extractable work than any other known inequality in the same setup. In addition, we demonstrate that the Mandal-Jarzynski model, which is a prominent model of the information reservoir formalism, is equivalent to a model obtained by the contraction of a bipartite system with autonomous measurement and feedback. Our results provide a unified view on the measurement-feedback and the information-reservoir formalisms.

  2. Enhancing System Realisation in Formal Model Development

    DEFF Research Database (Denmark)

    Tran-Jørgensen, Peter Würtz Vinther

    2016-01-01

    Software for mission-critical systems is sometimes analysed using formal specification to increase the chances of the system behaving as intended. When sufficient insights into the system have been obtained from the formal analysis, the formal specification is realised in the form of a software...... implementation. One way to realise the system’s software is by automatically generating it from the formal specification – a technique referred to as code generation. However, in general it is difficult to make guarantees about the correctness of the generated code – especially while requiring automation of the...... steps involved in realising the formal specification. This PhD dissertation investigates ways to improve the automation of the steps involved in realising and validating a system based on a formal specification. The approach aims to develop properly designed software tools which support the integration...

  3. Formalizing the slow-roll approximation in inflation

    Science.gov (United States)

    Liddle, Andrew R.; Parsons, Paul; Barrow, John D.

    1994-12-01

    The meaning of the inflationary slow-roll approximation is formalized. Comparisons are made between an approach based on the Hamilton-Jacobi equations, governing the evolution of the Hubble parameter, and the usual scenario based on the evolution of the potential energy density. The vital role of the inflationary attractor solution is emphasized, and some of its properties described. We propose a new measure of inflation, based upon contraction of the comoving Hubble length as opposed to the usual e-foldings of physical expansion, and derive relevant formulas. We introduce an infinite hierarchy of slow-roll parameters, and show that only a finite number of them are required to produce results to a given order. The extension of the slow-roll approximation into an analytic slow-roll expansion, converging on the exact solution, is provided. Its role in calculations of inflationary dynamics is discussed. We explore rational approximants as a method of extending the range of convergence of the slow-roll expansion up to, and beyond, the end of inflation.

  4. M-Theory in the Gaugeon Formalism

    Institute of Scientific and Technical Information of China (English)

    Mir Faizal

    2012-01-01

    In this paper we will analyse the Aharony-Bergman-Jafferis-Maldacena (ABJM) theory in N = 1 superspace formalism. We then study the quantum gauge transformations for this ABJM theory in gaugeon formalism. We will also analyse the extended BRST symmetry for this ABJM theory in gaugeon formalism and show that these BRST transformations for this theory are nilpotent and this in turn leads to the unitary evolution of the S-matrix.

  5. Quantum formalism to describe binocular rivalry

    OpenAIRE

    Manousakis, Efstratios

    2007-01-01

    On the basis of the general character and operation of the process of perception, a formalism is sought to mathematically describe the subjective or abstract/mental process of perception. It is shown that the formalism of orthodox quantum theory of measurement, where the observer plays a key role, is a broader mathematical foundation which can be adopted to describe the dynamics of the subjective experience. The mathematical formalism describes the psychophysical dynamics of the subjective or...

  6. Survey of Existing Tools for Formal Verification.

    Energy Technology Data Exchange (ETDEWEB)

    Punnoose, Ratish J.; Armstrong, Robert C.; Wong, Matthew H.; Jackson, Mayo

    2014-12-01

    Formal methods have come into wide use because of their effectiveness in verifying "safety and security" requirements of digital systems; a set of requirements for which testing is mostly ineffective. Formal methods are routinely used in the design and verification of high-consequence digital systems in industry. This report outlines our work in assessing the capabilities of commercial and open source formal tools and the ways in which they can be leveraged in digital design workflows.

  7. A Mathematical Formalization Proposal for Business Growth

    OpenAIRE

    Gheorghe BAILESTEANU; Diana TARNAVEANU

    2013-01-01

    Economic sciences have known a spectacular evolution in the last century; beginning to use axiomatic methods, applying mathematical instruments as a decision-making tool. The quest to formalization needs to be addressed from various different angles, reducing entry and operating formal costs, increasing the incentives for firms to operate formally, reducing obstacles to their growth, and searching for inexpensive approaches through which to enforce compliancy with government regulations. This...

  8. CYCLIC CODES OVER FORMAL POWER SERIES RINGS

    Institute of Scientific and Technical Information of China (English)

    Dougherty Steven T.; Liu Hongwei

    2011-01-01

    In this article, cyclic codes and negacyclic codes over formal power series rings are studied. The structure of cyclic codes over this class of rings is given, and the relationship between these codes and cyclic codes over finite chain rings is obtained. Using an isomorphism between cyclic and negacyclic codes over formal power series rings, the structure of negacyclic codes over the formal power series rings is obtained.

  9. Formalization of P Systems by Maude

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Rewriting logic is a unified model of concurrency, which provides a formal common framework of wellknown models of concurrent systems. A new formal method of the specification and execution of P systems using rewriting logic was proposed. The powerful tool Maude 2.0 is used to implement this specification. In order to present the general ideas in a concrete case study, a simple and classical example from the literature is adopted to present how to formally specify and execute a P system.

  10. Wild attractors and thermodynamic formalism

    CERN Document Server

    Bruin, Henk

    2012-01-01

    Fibonacci unimodal maps can have a wild Cantor attractor, and hence be Lebesgue dissipative, depending on the order of the critical point. We present a one-parameter family $f_\\lambda$ of countably piecewise linear unimodal Fibonacci maps in order to study the thermodynamic formalism of dynamics where dissipativity of Lebesgue (and conformal) measure is responsible for phase transitions. We show that for the potential $\\phi_t = -t\\log|f'_\\lambda|$, there is a unique phase transition at some $t_1 \\le 1$, and the pressure $P(\\phi_t)$ is analytic (with unique equilibrium state) elsewhere. The pressure is majorised by a non-analytic $C^\\infty$ curve (with all derivatives equal to 0 at $t_1 < 1$) at the emergence of a wild attractor, whereas the phase transition at $t_1 = 1$ can be of any finite order for those $\\lambda$ for which $f_\\lambda$ is Lebesgue conservative. We also obtain results on the existence of conformal measures and equilibrium states, as well as the hyperbolic dimension and the dimension of th...

  11. Universal formalism of Fano resonance

    International Nuclear Information System (INIS)

    The phenomenon of Fano resonance is ubiquitous in a large variety of wave scattering systems, where the resonance profile is typically asymmetric. Whether the parameter characterizing the asymmetry should be complex or real is an issue of great experimental interest. Using coherent quantum transport as a paradigm and taking into account of the collective contribution from all available scattering channels, we derive a universal formula for the Fano-resonance profile. We show that our formula bridges naturally the traditional Fano formulas with complex and real asymmetry parameters, indicating that the two types of formulas are fundamentally equivalent (except for an offset). The connection also reveals a clear footprint for the conductance resonance during a dephasing process. Therefore, the emergence of complex asymmetric parameter when fitting with experimental data needs to be properly interpreted. Furthermore, we have provided a theory for the width of the resonance, which relates explicitly the width to the degree of localization of the close-by eigenstates and the corresponding coupling matrices or the self-energies caused by the leads. Our work not only resolves the issue about the nature of the asymmetry parameter, but also provides deeper physical insights into the origin of Fano resonance. Since the only assumption in our treatment is that the transport can be described by the Green’s function formalism, our results are also valid for broad disciplines including scattering problems of electromagnetic waves, acoustics, and seismology

  12. Expansion of Pannes

    Science.gov (United States)

    For the Long Island, New Jersey, and southern New England region, one facet of marsh drowning as a result of accelerated sea level rise is the expansion of salt marsh ponds and pannes. Over the past century, marsh ponds and pannes have formed and expanded in areas of poor drainag...

  13. THESAURUS AND QUERY EXPANSION

    Directory of Open Access Journals (Sweden)

    Hazra Imran

    2009-11-01

    Full Text Available The explosive growth of the World Wide Web is making it difficult for a user to locate information that isrelevant to his/her interest. Though existing search engines work well to a certain extent but they still faceproblems like word mismatch which arises because the majority of information retrieval systemscompare query and document terms on lexical level rather than on semantic level and short query: theaverage length of queries by the user is less than two words. Short queries and the incompatibilitybetween the terms in user queries and documents strongly affect the retrieval of relevant document.Query expansion has long been suggested as a technique to increase the effectiveness of the informationretrieval. Query expansion is the process of supplementing additional terms or phrases to the originalquery to improve the retrieval performance. The central problem of query expansion is the selection ofthe expansion terms based on which user’s original query is expanded. Thesaurus helps to solve thisproblem. Thesaurus have frequently been incorporated in information retrieval system for identifying thesynonymous expressions and linguistic entities that are semantically similar. Thesaurus has been widelyused in many applications, including information retrieval and natural language processing.

  14. OPEC future capacity expansions

    International Nuclear Information System (INIS)

    This conference presentation examined OPEC future capacity expansions including highlights from 2000-2004 from the supply perspective and actions by OPEC; OPEC spare capacity in 2005/2006; medium-term capacity expansion and investments; long-term scenarios, challenges and opportunities; and upstream policies in member countries. Highlights from the supply perspective included worst than expected non-OPEC supply response; non-OPEC supply affected by a number of accidents and strikes; geopolitical tensions; and higher than expected demand for OPEC crude. OPEC's actions included closer relationship with other producers and consumers; capacity expansions in 2004 and 2005/2006; and OPEC kept the market well supplied with crude in 2004. The presentation also provided data using graphical charts on OPEC net capacity additions until 2005/2006; OPEC production versus spare capacity from 2003 to 2005; OPEC production and capacity to 2010; and change in required OPEC production from 2005-2020. Medium term expansion to 2010 includes over 60 projects. Medium-term risks such as project execution, financing, costs, demand, reserves, depletion, integration of Iraq, and geopolitical tensions were also discussed. The presentation concluded that in the long term, large uncertainties remain; the peak of world supply is not imminent; and continued and enhanced cooperation is essential to market stability. tabs., figs

  15. Bed expansion crucible tests

    International Nuclear Information System (INIS)

    The Am/Cm program will vitrify the americium and curium currently stored in F-canyon. A batch flowsheet has been developed (with non-radioactive surrogate feed in place of the F-canyon solution) and tested full-scale in the 5-inch Cylindrical Induction Melter (CIM) facility at TNX. During a normal process run, a small bed expansion occurs when oxygen released from reduction of cerium (IV) oxide to cerium (III) oxide is trapped in highly viscous glass. The bed expansion is characterized by a foamy layer of glass that slowly expands as the oxygen is trapped and then dissipates when the viscosity of the foam becomes low enough to allow the oxygen to escape. Severe bed expansions were noted in the 5-inch CIM when re-heating after an interlock during the calcination phase of the heat cycle, escaping the confines of the melter vessel. In order to better understand the cause of the larger than normal bed expansion and to develop mitigating techniques, a series of three crucible tests were conducted

  16. Unifying Clifford algebra formalism for relativistic fields

    International Nuclear Information System (INIS)

    It is shown that a Clifford algebra formalism provides a unifying description of spin-0, -1/2, and -1 fields. Since the operators and operands are both expressed in terms of the same Clifford algebra, the formalism obtains some results which are considerably different from those of the standard of formalisms for these fields. In particular, the conservation laws are obtained uniquely and unambiguously from the equations of motion in this formalism and do not suffer from the ambiguities and inconsistencies of the standard methods

  17. Our dear boson – and so what?

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    A long-sought particle finally found. On Wednesday 4 July, enthusiasm spread from CERN to the worldwide media. But a question legitimately arises: why is this particle attracting so much interest? In other words, how is it different from all the others? (And, by the way, what is a boson?).   CERN, 4 July 2012: a long-sought particle finally found. Strictly speaking, we cannot even call it the “Higgs” boson yet. Only after careful checking of its properties will physicists be able to say if the new boson corresponds to the particle that theorists predicted in 1964. However, the experimental data we have so far already tells us, unambiguously, that this new particle is different from all the other elementary particles we know. “Every particle is either a boson or a fermion,” explains John Ellis, former CERN theorist and currently professor at King's College in London. “All known particles spin like small tops, with the known bosons tha...

  18. Interaction between bosonic dark matter and stars

    Science.gov (United States)

    Brito, Richard; Cardoso, Vitor; Macedo, Caio F. B.; Okawa, Hirotada; Palenzuela, Carlos

    2016-02-01

    We provide a detailed analysis of how bosonic dark matter "condensates" interact with compact stars, extending significantly the results of a recent Letter [1]. We focus on bosonic fields with mass mB , such as axions, axion-like candidates and hidden photons. Self-gravitating bosonic fields generically form "breathing" configurations, where both the spacetime geometry and the field oscillate, and can interact and cluster at the center of stars. We construct stellar configurations formed by a perfect fluid and a bosonic condensate, and which may describe the late stages of dark matter accretion onto stars, in dark-matter-rich environments. These composite stars oscillate at a frequency which is a multiple of f =2.5 ×1014(mBc2/eV ) Hz . Using perturbative analysis and numerical relativity techniques, we show that these stars are generically stable, and we provide criteria for instability. Our results also indicate that the growth of the dark matter core is halted close to the Chandrasekhar limit. We thus dispel a myth concerning dark matter accretion by stars: dark matter accretion does not necessarily lead to the destruction of the star, nor to collapse to a black hole. Finally, we argue that stars with long-lived bosonic cores may also develop in other theories with effective mass couplings, such as (massless) scalar-tensor theories.

  19. Ratio method of measuring W boson mass

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Feng [Stony Brook Univ., NY (United States)

    2010-08-01

    This dissertation describes an alternative method of measuring the W boson mass in DØ experiment. Instead of extracting MW from the fitting of W → ev fast Monte Carlo simulations to W → ev data as in the standard method, we make the direct fit of transverse mass between W → ev data and Z → ee data. One of the two electrons from Z boson is treated as a neutrino in the calculation of transverse mass. In ratio method, the best fitted scale factor corresponds to the ratio of W and Z boson mass (MW/MZ). Given the precisely measured Z boson mass, W mass is directly fitted from W → ev and Z → ee data. This dissertation demonstrates that ratio method is a plausible method of measuring the W boson mass. With the 1 fb-1 DØ Run IIa dataset, ratio method gives MW = 80435 ± 43(stat) ± 26(sys) MeV.

  20. U boson at the BES III detector

    International Nuclear Information System (INIS)

    The O(MeV) spin-1 U boson has been proposed to mediate the interaction among electron-positron and O(MeV) dark matter, in order to account for the 511 keV γ-ray observation by SPI/INTEGRAL. In this paper the observability of such a kind of U boson at BESIII is investigated through the processes e+e-→Uγ and e+e-→J/Ψ→e+e-U. We find that BESIII and high luminosity B factories have a comparable capacity to detect such a U boson. If the U boson decays mainly into dark matter, i.e. invisibly, BESIII can measure the coupling between the U boson and an electron-positron pair geR (see text) down to O(10-5), and cover large parameter space which can account for 511 keV γ-ray observation. On the other hand, provided that U decays mainly into the electron-positron, BESIII can detect geR down to O(10-3), and it is hard to explore the 511 keV γ-ray measurement allowed parameter space due to the irreducible QED backgrounds

  1. ATLAS measurements of vector boson production

    CERN Document Server

    Debenedetti, Chiara; The ATLAS collaboration

    2016-01-01

    Vector boson production in pp collisions at 7, 8 and 13 TeV has been extensively studied by ATLAS. Recent results include the precision measurements of the transverse momentum of the Z/gamma* boson production, sensitive to soft resummation effects, hard jet emissions and electroweak corrections. A precise measurement of the angular coefficients of the Z­boson production tests the underlying QCD dynamics of the Drell­Yan process. A first measurement of the inclusive W and Z cross section at a cms energy of 13TeV has been derived. The Production of jets in association with a vector boson is an important process to study QCD in a multi­scale environment. Cross sections, differential in several kinematics variables, have been measured with the ATLAS detector and compared to state­of­the­art QCD calculations and Monte Carlo simulations. First measurements of vector boson + jets production have been performed at cms energies of 13TeV. An overview of these results is given.

  2. Ratio method of measuring $w$ boson mass

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Feng; /SUNY, Stony Brook

    2010-08-01

    This dissertation describes an alternative method of measuring the W boson mass in D0 experiment. Instead of extracting M{sub W} from the fitting of W {yields} e{nu} fast Monte Carlo simulations to W {yields} e{nu} data as in the standard method, we make the direct fit of transverse mass between W {yields} e{nu} data and Z {yields} ee data. One of the two electrons from Z boson is treated as a neutrino in the calculation of transverse mass. In ratio method, the best fitted scale factor corresponds to the ratio of W and Z boson mass (M{sub W}/M{sub Z}). Given the precisely measured Z boson mass, W mass is directly fitted from W {yields} e{nu} and Z {yields} ee data. This dissertation demonstrates that ratio method is a plausible method of measuring the W boson mass. With the 1 fb{sup -1} D0 Run IIa dataset, ratio method gives M{sub W} = 80435 {+-} 43(stat) {+-} 26(sys) MeV.

  3. Correlations in charged bosons systems

    International Nuclear Information System (INIS)

    The two and three-dimensional charge Bose gas have been studied. In the bidimensional case two different types of interaction were considered: l/r and l n(r). The method of self-consistent-field was applied to these systems, which takes into account the short range correlations between the bosons through a local-field correction. By using self-consistent numerical calculations, the structure factor S(k→) was determined. The pair-correlation function, the ground-state energy, the pressure of the gas and the spectrum of elementary excitations were obtained from S (k→). The screening density induced by a fixed charged impurity was calculated. In the high-density limit our calculations reproduce the results given by Bogoliubov's perturbation theory. In the intermediate-density region, corresponding to the strongly coupled systems, the results are in very good agreement with calculations based on HNC approximation as well as Monte Carlo method. The results are compared in several situations with RPA results showing that the self-consistent method is much more accurate. The two-dimensional systems showed to be more correlated than the three-dimensional systems showed to be more correlated than the three-dimensional one; the gas with interaction l/r is also more correlated than the logarithmic one at high densities, but it begins to be less correlated than this one in the low-density region. The thermodynamic functions of the two and three-dimensional systems at finite temperatures near absolute zero are calculated based upon the gas excitation spectra at zero temperature. (author)

  4. Orbital optical lattices with bosons

    Science.gov (United States)

    Kock, T.; Hippler, C.; Ewerbeck, A.; Hemmerich, A.

    2016-02-01

    This article provides a synopsis of our recent experimental work exploring Bose-Einstein condensation in metastable higher Bloch bands of optical lattices. Bipartite lattice geometries have allowed us to implement appropriate band structures, which meet three basic requirements: the existence of metastable excited states sufficiently protected from collisional band relaxation, a mechanism to excite the atoms initially prepared in the lowest band with moderate entropy increase, and the possibility of cross-dimensional tunneling dynamics, necessary to establish coherence along all lattice axes. A variety of bands can be selectively populated and a subsequent thermalization process leads to the formation of a condensate in the lowest energy state of the chosen band. As examples the 2nd, 4th and 7th bands in a bipartite square lattice are discussed. The geometry of the 2nd and 7th bands can be tuned such that two inequivalent energetically degenerate energy minima arise at the X ±-points at the edge of the 1st Brillouin zone. In this case even a small interaction energy is sufficient to lock the phase between the two condensation points such that a complex-valued chiral superfluid order parameter can emerge, which breaks time reversal symmetry. In the 4th band a condensate can be formed at the Γ-point in the center of the 1st Brillouin zone, which can be used to explore topologically protected band touching points. The new techniques to access orbital degrees of freedom in higher bands greatly extend the class of many-body scenarios that can be explored with bosons in optical lattices.

  5. Appendix: Chapman-Enskog Expansion in the Lattice Boltzmann Method

    CERN Document Server

    Li, Jun

    2015-01-01

    The Chapman-Enskog expansion was used in the lattice Boltzmann method (LBM) to derive a Navier-Stokes-like equation and a formula was obtained to correlate the LBM model parameters to the kinematic viscosity implicitly implemented in LBM simulations. The obtained correlation formula usually works as long as the model parameters are carefully selected to make the Mach number and Knudsen number small although the validity of Chapman-Enskog expansion that has a formal definition of time derivative without tangible mathematical sense is not recognized by many mathematicians.

  6. Vector and Axial-vector resonances in composite models of the Higgs boson

    CERN Document Server

    Franzosi, Diogo Buarque; Cai, Haiying; Deandrea, Aldo; Frandsen, Mads

    2016-01-01

    We provide a non-linear realisation of composite Higgs models in the context of the SU(4)/Sp(4) symmetry breaking pattern, where the effective Lagrangian of the spin-0 and spin-1 resonances is constructed via the CCWZ prescription using the Hidden Symmetry formalism. We investigate the EWPT constraints by accounting the effects from reduced Higgs couplings and integrating out heavy spin-1 resonances. This theory emerges from an underlying theory of gauge interactions with fermions, thus first principle lattice results predict the massive spectrum in composite Higgs models. This model can be used as a template for the phenomenology of composite Higgs models at the LHC and at future 100 TeV colliders, as well as for other application. In this work, we focus on the formalism for spin-1 resonances and their bounds from di-lepton and di-boson searches at the LHC.

  7. Feshbach resonances and weakly bound molecular states of boson-boson and boson-fermion NaK pairs

    OpenAIRE

    Viel, Alexandra; Simoni, Andrea

    2016-01-01

    We study theoretically magnetically induced Feshbach resonances and near-threshold bound states in isotopic NaK pairs. Our calculations accurately reproduce Feshbach spectroscopy data on Na$^{40}$K and explain the origin of the observed multiplets in the p-wave [Phys. Rev. A 85, 051602(R) (2012)]. We apply the model to predict scattering and bound state threshold properties of the boson-boson Na$^{39}$K and Na$^{41}$K systems. We find that the Na$^{39}$K isotopic pair presents broad magnetic ...

  8. Hexadecapole degree of freedom in the interacting boson model

    International Nuclear Information System (INIS)

    The hexadecapole degree of freedom in the interacting boson models with sd and sdg bosons is reviewed with the aim of providing experimental signatures that distinguish between the two models. (orig.)

  9. Bosonic Dp-branes at finite temperature in TFD approach

    Science.gov (United States)

    Abdalla, M. C. B.; Gadelha, A. L.; Vancea, I. V.

    2004-02-01

    A general formulation of Thermo Field Dynamics using transformation generators that form the SU(1, 1) group, is presented and applied to the closed bosonic string and for bosonic Dp-brane with an external field.

  10. Bosonic Dp-branes at finite temperature in TFD approach

    Energy Technology Data Exchange (ETDEWEB)

    Abdalla, M.C.B.; Gadelha, A.L.; Vancea, I.V

    2004-02-01

    A general formulation of Thermo Field Dynamics using transformation generators that form the SU(1, 1) group, is presented and applied to the closed bosonic string and for bosonic D{sub p}-brane with an external field.

  11. Bosonic Dp-branes at finite temperature in TFD approach

    International Nuclear Information System (INIS)

    A general formulation of Thermo Field Dynamics using transformation generators that form the SU(1, 1) group, is presented and applied to the closed bosonic string and for bosonic Dp-brane with an external field

  12. Higgs bosons in the standard model, the MSSM and beyond

    Indian Academy of Sciences (India)

    John F Gunion

    2004-02-01

    I summarize the basic theory and selected phenomenology for the Higgs boson(s) of the standard model, the minimal supersymmetric model and some extensions thereof, including the next-to-minimal supersymmetric model.

  13. Integrability and Quantum Phase Transitions in Interacting Boson Models

    CERN Document Server

    Dukelsky, J; García-Ramos, J E; Pittel, S

    2003-01-01

    The exact solution of the boson pairing hamiltonian given by Richardson in the sixties is used to study the phenomena of level crossings and quantum phase transitions in the integrable regions of the sd and sdg interacting boson models.

  14. Search for a Higgs Boson Produced in Association with a W Boson at ATLAS

    CERN Document Server

    Ruckert, Benjamin

    The Large Hadron Collider at CERN is the most modern proton-proton collider and data taking will start in 2009, with a centre-of-mass energy of 7 TeV. The ATLAS detector, which is one of two multi-purpose detectors at the Large Hadron Collider, is able to detect a Standard Model Higgs boson if it exists. This is one of the main tasks of the ATLAS experiment. This thesis deals with a Standard Model Higgs boson produced in association with a W boson. The Monte Carlo study is based on physics events generated at the nominal centre-of-mass energy of the Large Hadron Collider of 14 TeV. Large parts of this analysis have been done using the global Grid infrastructure of the Large Hadron Collider experiments. A mass range of the Higgs boson of mH = 130 - 190 GeV has been taken into account. In this mass range, the Higgs boson dominantly decays into a pair of W bosons, leading to initially three W bosons: WH -> WWW. Two orthogonal analysis channels have been investigated in detailed studies of the background properti...

  15. Formal language constrained path problems

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, C.; Jacob, R.; Marathe, M.

    1997-07-08

    In many path finding problems arising in practice, certain patterns of edge/vertex labels in the labeled graph being traversed are allowed/preferred, while others are disallowed. Motivated by such applications as intermodal transportation planning, the authors investigate the complexity of finding feasible paths in a labeled network, where the mode choice for each traveler is specified by a formal language. The main contributions of this paper include the following: (1) the authors show that the problem of finding a shortest path between a source and destination for a traveler whose mode choice is specified as a context free language is solvable efficiently in polynomial time, when the mode choice is specified as a regular language they provide algorithms with improved space and time bounds; (2) in contrast, they show that the problem of finding simple paths between a source and a given destination is NP-hard, even when restricted to very simple regular expressions and/or very simple graphs; (3) for the class of treewidth bounded graphs, they show that (i) the problem of finding a regular language constrained simple path between source and a destination is solvable in polynomial time and (ii) the extension to finding context free language constrained simple paths is NP-complete. Several extensions of these results are presented in the context of finding shortest paths with additional constraints. These results significantly extend the results in [MW95]. As a corollary of the results, they obtain a polynomial time algorithm for the BEST k-SIMILAR PATH problem studied in [SJB97]. The previous best algorithm was given by [SJB97] and takes exponential time in the worst case.

  16. The Bargmann-Wigner Formalism for Higher Spins (up to 2)

    CERN Document Server

    Dvoeglazov, Valeriy V

    2011-01-01

    On the basis of our recent modifications of the Dirac formalism we generalize the Bargmann-Wigner formalism for higher spins to be compatible with other formalisms for bosons. Relations with dual electrodynamics, with the Ogievetskii-Polubarinov notoph and the Weinberg 2(2S+1) theory are found. Next, we proceed to derive the equations for the symmetric tensor of the second rank on the basis of the Bargmann-Wigner formalism in a straightforward way. The symmetric multispinor of the fourth rank is used. It is constructed out of the Dirac 4-spinors. Due to serious problems with the interpretation of the results obtained on using the standard procedure we generalize it and obtain the spin-2 relativistic equations, which are consistent with the previous one. We introduce the dual analogues of the Riemann tensor and derive corresponding dynamical equations in the Minkowski space. Relations with the Marques-Spehler chiral gravity theory are discussed. The importance of the 4-vector field (and its gauge part) is poin...

  17. Bosonization of Weyl Fermions and Free Electrons

    CERN Document Server

    Marino, E C

    2015-01-01

    The electron, discovered by Thomson by the end of the nineteenth century, was the first experimentally observed particle. The Weyl fermion, though theoretically predicted since a long time, was observed in a condensed matter environment in an experiment reported only a few weeks ago. Is there any linking thread connecting the first and the last observed fermion (quasi)particles? The answer is positive. By generalizing the method known as bosonization, the first time in its full complete form, for a spacetime with 3+1 dimensions, we are able to show that both electrons and Weyl fermions can be expressed in terms of the same boson field, namely the Kalb-Ramond anti-symmetric tensor gauge field. The bosonized form of the Weyl chiral currents lead to the angle-dependent magneto-conductance behavior observed in these systems.

  18. Light gauge boson in rare $K$ decay

    CERN Document Server

    Chen, Chuan-Hung

    2016-01-01

    The inconsistent conclusions for a light gauge boson $X$ production in the $K^- \\to \\pi^- X$ exist in the literature. It is found that the process can be generated by the tree-level $W$-boson annihilation and loop-induced $s\\to dX$. We find that it strongly depends on the $SU(3)$ limit or the unique gauge coupling to the quarks, whether the $K^-\\to \\pi^- X$ decay, which is from the $W$-boson annihilation, is suppressed by $m^2_X \\epsilon_X \\cdot p_K$; however, no such suppression is found via the loop-induced $s\\to d X$. The constraints on the relevant couplings are studied.

  19. W Boson Polarisation at LEP2

    CERN Document Server

    Abbiendi, G; Åkesson, P F; Alexander, G; Allison, J; Amaral, P; Anagnostou, G; Anderson, K J; Arcelli, S; Asai, S; Axen, D A; Azuelos, Georges; Bailey, I; Barberio, E; Barillari, T; Barlow, R J; Batley, J Richard; Bechtle, P; Behnke, T; Bell, K W; Bell, P J; Bella, G; Bellerive, A; Benelli, G; Bethke, Siegfried; Biebel, O; Boeriu, O; Bock, P; Boutemeur, M; Braibant, S; Brigliadori, L; Brown, R M; Büsser, K; Burckhart, H J; Campana, S; Carnegie, R K; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Ciocca, C; Couchman, J; Csilling, Akos; Cuffiani, M; Dado, S; de Roeck, A; De Wolf, E A; Desch, Klaus; Dienes, B; Donkers, M; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Etzion, E; Fabbri, Franco Luigi; Feld, L; Ferrari, P; Fiedler, F; Fleck, I; Ford, M; Frey, A; Gagnon, P; Gary, J W; Gaycken, G; Geich-Gimbel, C; Giacomelli, G; Giacomelli, P; Giunta, M; Goldberg, J; Gross, E; Grunhaus, Jacob; Gruwé, M; Günther, P O; Sen-Gupta, A; Hajdu, C; Hamann, M; Hanson, G G; Harel, A; Hauschild, M; Hawkes, C M; Hawkings, R; Hemingway, Richard J; Herten, G; Heuer, R D; Hill, J C; Hoffman, K; Horváth, D; Igo-Kemenes, P; Ishii, K; Jeremie, H; Jovanovic, P; Junk, T R; Kanaya, N; Kanzaki, J; Karlen, Dean A; Kawagoe, K; Kawamoto, T; Keeler, Richard K; Kellogg, R G; Kennedy, B W; Klein, K; Klier, A; Kluth, S; Kobayashi, T; Kobel, M; Komamiya, S; Kramer, T; Krieger, P; Von Krogh, J; Krüger, K; Kühl, T; Kupper, M; Lafferty, G D; Landsman, Hagar Yaël; Lanske, D; Layter, J G; Lellouch, D; Letts, J; Levinson, L; Lillich, J; Lloyd, S L; Loebinger, F K; Lü, J; Ludwig, A; Ludwig, J; Mader, W; Marcellini, S; Martin, A J; Masetti, G; Mashimo, T; Mättig, P; McKenna, J A; McPherson, R A; Meijers, F; Menges, W; Merritt, F S; Mes, H; Michelini, Aldo; Mihara, S; Mikenberg, G; Miller, D J; Moed, S; Mohr, W; Mori, T; Mutter, A; Nagai, K; Nakamura, I; Nanjo, H; Neal, H A; Nisius, R; O'Neale, S W; Oh, A; Okpara, A N; Oreglia, M J; Orito, S; Pahl, C; Pásztor, G; Pater, J R; Pilcher, J E; Pinfold, J L; Plane, D E; Poli, B; Pooth, O; Przybycien, M B; Quadt, A; Rabbertz, K; Rembser, C; Renkel, P; Roney, J M; Rosati, S; Rozen, Y; Runge, K; Sachs, K; Saeki, T; Sarkisyan-Grinbaum, E; Schaile, A D; Schaile, O; Scharff-Hansen, P; Schieck, J; Schörner-Sadenius, T; Schröder, M; Schumacher, M; Scott, W G; Seuster, R; Shears, T G; Shen, B C; Sherwood, P; Skuja, A; Smith, A M; Sobie, R J; Söldner-Rembold, S; Spanó, F; Stahl, A; Strom, D; Ströhmer, R; Tarem, S; Tasevsky, M; Teuscher, R; Thomson, M A; Torrence, E; Toya, D; Tran, P; Trigger, I; Trócsányi, Z L; Tsur, E; Turner-Watson, M F; Ueda, I; Ujvári, B; Vollmer, C F; Vannerem, P; Vertesi, R; Verzocchi, M; Voss, H; Vossebeld, Joost Herman; Waller, D; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wetterling, D; Wilson, G W; Wilson, J A; Wolf, G; Wyatt, T R; Yamashita, S; Zer-Zion, D; Zivkovic, L

    2004-01-01

    Elements of the spin density matrix for W bosons in e+e- -> W+W- -> qqln events are measured from data recorded by the OPAL detector at LEP. This information is used calculate polarised differential cross-sections and to search for CP-violating effects. Results are presented for W bosons produced in e+e- collisions with centre-of-mass energies between 183 GeV and 209 GeV. The average fraction of W bosons that are longitudinally polarised is found to be (23.9 +- 2.1 +- 1.1)% compared to a Standard Model prediction of (23.9 +- 0.1)%. All results are consistent with CP conservation.

  20. Efficient experimental validation of photonic boson sampling

    CERN Document Server

    Spagnolo, N; Bentivegna, M; Brod, D J; Crespi, A; Flamini, F; Giacomini, S; Milani, G; Ramponi, R; Mataloni, P; Osellame, R; Galvao, E F; Sciarrino, F

    2013-01-01

    A boson sampling device is a specialised quantum computer that solves a problem which is strongly believed to be computationally hard for classical computers. Recently a number of small-scale implementations have been reported, all based on multi-photon interference in multimode interferometers. In the hard-to-simulate regime, even validating the device's functioning may pose a problem. In a recent criticism of boson sampling experiments, Gogolin et al. argued that the output would be effectively indistinguishable from the trivial, uniform distribution. Here we report new boson sampling experiments on larger photonic chips, and analyse the data using a scalable statistical test recently proposed by Aaronson and Arkhipov. We show the test successfully validates small experimental data samples against the hypothesis that they are uniformly distributed. We also show how to discriminate data arising from either indistinguishable or distinguishable photons. Our results pave the way towards demonstrating the quantu...

  1. Fidelities in the spin-boson model

    Science.gov (United States)

    Lukyanov, Sergei L.

    2016-04-01

    The spin-boson model (or the dissipative two-state system) is a model for the study of dissipation and decoherence in quantum mechanics. The spin-boson model with Ohmic dissipation is an integrable theory, related to several other integrable systems including the anisotropic Kondo and resonant level models. Here we consider the problem of computing the overlaps between two ground states corresponding to different values of parameters of the Ohmic spin-boson Hamiltonian. We argue that this can be understood as a part of the problem of quantizing the mKdV/sine-Gordon integrable hierarchy. The main objective of this work is to analyze how the Anderson orthogonality affects the Yang-Baxter integrable structure underlying the theory.

  2. QCD corrections to Higgs boson decays

    International Nuclear Information System (INIS)

    The two-loop OMIKRON (αsGFmt2) corrections to the b anti b decay rate of the Standard Model Higgs boson as well as its production via e+e-→ZH will be presented. These QCD corrections are obtained by using a low-energy theorem for light Higgs bosons compared to the top quark mass. The results yield strong screening effects of the OMIKRON (GFmt2) contributions. After that the two-loop QCD corrections to the γγ and gluonic decays of the Higgs bosons of the Standard Model and its minimal supersymmetric extension are discussed. While the corrections to the γγ decays remain small of OMIKRON (αs) they are huge ∝50-70% in the case of the gluonic decays. (orig.)

  3. Improved effective vector boson approximation revisited

    Science.gov (United States)

    Bernreuther, Werner; Chen, Long

    2016-03-01

    We reexamine the improved effective vector boson approximation which is based on two-vector-boson luminosities Lpol for the computation of weak gauge-boson hard scattering subprocesses V1V2→W in high-energy hadron-hadron or e-e+ collisions. We calculate these luminosities for the nine combinations of the transverse and longitudinal polarizations of V1 and V2 in the unitary and axial gauge. For these two gauge choices the quality of this approach is investigated for the reactions e-e+→W-W+νeν¯ e and e-e+→t t ¯ νeν¯ e using appropriate phase-space cuts.

  4. Critical Scaling and a Dynamical Higgs Boson

    CERN Document Server

    Mannheim, Philip D

    2016-01-01

    In a quantum electrodynamics theory that is realized by critical scaling and anomalous dimensions, even though the fermion mass is generated dynamically, the Lagrangian is not chiral invariant and no dynamical pseudoscalar Goldstone boson or scalar Higgs boson accompanies the mass generation. In the mean-field approximation to a chiral invariant four-fermion theory there is also dynamical mass generation. However, the associated mean-field sector Lagrangian is not chirally invariant and possesses no dynamical bound states, with Goldstone and Higgs boson bound states instead being generated by the residual interaction. In this paper we show that if a critical scaling electrodynamics is augmented with a four-fermion interaction, precisely because it possesses no dynamical bound states the electrodynamic sector can be reinterpreted as a mean-field approximation to a larger theory that is chiral symmetric, and in this larger theory there is a residual interaction that then does generate dynamical Goldstone and Hi...

  5. Boson Stars in AdS

    CERN Document Server

    Buchel, Alex; Lehner, Luis

    2013-01-01

    We construct boson stars in global Anti de Sitter (AdS) space and study their stability. Linear perturbation results suggest that the ground state along with the first three excited state boson stars are stable. We evolve some of these solutions and study their nonlinear stability in light of recent work \\cite{Bizon:2011gg} arguing that a weakly turbulent instability drives scalar perturbations of AdS to black hole formation. However evolutions suggest that boson stars are nonlinearly stable and immune to the instability for sufficiently small perturbation. Furthermore, these studies find other families of initial data which similarly avoid the instability for sufficiently weak parameters. Heuristically, we argue that initial data families with widely distributed mass-energy distort the spacetime sufficiently to oppose the coherent amplification favored by the instability. From the dual CFT perspective our findings suggest that there exist families of rather generic initial conditions in strongly coupled CFT ...

  6. The general boson normal ordering problem

    CERN Document Server

    Blasiak, P; Solomon, A I; Blasiak, Pawel; Penson, Karol A.; Solomon, Allan I.

    2003-01-01

    We solve the boson normal ordering problem for F[(a*)^r a^s], with r,s positive integers, where a* and a are boson creation and annihilation operators satisfying [a,a*]=1. That is, we provide exact and explicit expressions for the normal form wherein all a's are to the right. The solution involves integer sequences of numbers which are generalizations of the conventional Bell and Stirling numbers whose values they assume for r=s=1. A comprehensive theory of such generalized combinatorial numbers is given including closed-form expressions (extended Dobinski-type formulas)and generating functions. These last are special expectation values in boson coherent states.

  7. Triplet Higgs boson at hadron colliders

    International Nuclear Information System (INIS)

    The novel feature of a Higgs-triplet representation is a nonzero tree-level coupling of H+W-Z, which is absent in all Higgs-doublet models. We study the associated production of a singly-charged Higgs boson of the Higgs-triplet representation with a W or Z boson at hadron colliders, followed by the H+→W+Z decay. We find that the 2l+4j final state gives an interesting level of signal with a negligible background, plus it allows a full mass reconstruction of the charged-Higgs boson. The cover range of the charged-Higgs mass is between 110 and 200 GeV. (author)

  8. Elementary Goldstone Higgs Boson and Dark Matter

    DEFF Research Database (Denmark)

    Alanne, Tommi; Gertov, Helene; Sannino, Francesco;

    2015-01-01

    We investigate a perturbative extension of the Standard Model featuring elementary pseudo-Goldstone Higgs and dark matter particles. These are two of the five Goldstone bosons parametrising the SU(4)/Sp(4) coset space. They acquire masses, and therefore become pseudo-Goldstone bosons, due...... of the theory, the quantum corrections are precisely calculable. The remaining pseudo-Goldstone boson is identified with the dark matter candidate because it is neutral with respect to the Standard Model and stable. By a direct comparison with the Large Hadron Collider experiments, the model is found...... to be phenomenologically viable. Furthermore the dark matter particle leads to the observed thermal relic density while respecting the most stringent current experimental constraints....

  9. Locally smeared operator product expansions in scalar field theory

    CERN Document Server

    Monahan, Christopher

    2015-01-01

    We propose a new "locally smeared operator product expansion" (sOPE) to decompose non-local operators in terms of a basis of smeared operators. The sOPE formally connects nonperturbative matrix elements determined numerically using lattice field theory to matrix elements of non-local operators in the continuum. These nonperturbative matrix elements do not suffer from power-divergent mixing on the lattice, which significantly complicates calculations of quantities such as the moments of parton distribution functions, provided the smearing scale is kept fixed in the continuum limit. The presence of this smearing scale complicates the connection to the Wilson coefficients of the standard operator product expansion and requires the construction of a suitable formalism. We demonstrate the feasibility of our approach with examples in real scalar field theory.

  10. Cascade Decays of Triplet Higgs Bosons at LEP2

    CERN Document Server

    Akeroyd, A G

    1998-01-01

    We study the Georgi-Machacek two triplet, one doublet model in the context of LEP2, and show that cascade decays of Higgs bosons to lighter Higgs bosons and a virtual vector boson may play a major role. Such decays would allow the Higgs bosons of this model to escape current searches, and in particular are of great importance for the members of the five-plet which will always decay to the three-plet giving rise to cascade signatures.

  11. NLO QCD corrections to Wγ production via vector boson fusion

    International Nuclear Information System (INIS)

    Vector boson fusion processes will be used to probe the mechanism of electroweak symmetry breaking at the LHC. Wγ production via vector boson fusion is expected to yield important information on triple and quartic vector boson couplings. We have implemented the full next-to-leading order QCD corrections to Wγ production via vector boson fusion in a flexible parton-level Monte Carlo program, VBFNLO. Here we present our results.

  12. The Physics of New U(1)' Gauge Bosons

    OpenAIRE

    Langacker, Paul

    2009-01-01

    Additional Z' gauge bosons are predicted by a wide variety of extensions of the standard model (SM). Possibilities include TeV-scale bosons with electroweak coupling, very light bosons which nearly decouple from the standard model particles, and bosons which communicate with a quasi-hidden sector. A broad survey is given of the theoretical possibilities and of the physics implications for particle physics and cosmology. Several novel examples, including light Z's suggested by PAMELA, Stueckel...

  13. Standard electroweak interactions and Higgs bosons

    Energy Technology Data Exchange (ETDEWEB)

    Cox, B.; Gilman, F.J.

    1984-09-01

    In the standard model, only one basic component remains to be found: the Higgs boson. The specifics of Higgs boson production and detection, with decay to t anti t and a particular t quark mass range in mind, have not been examined in detail. As such, the working group on Standard Electroweak Interactions and Higgs Bosons at this meeting decided to concentrate on Higgs boson production and detection at SSC energies in the particular case where the Higgs mass is in the range so as to make t anti t quark-antiquark pairs the dominant decay mode. The study of this case, that of the so-called intermediate mass Higgs, had already been launched in the Berkeley PSSC Workshop on Electroweak Symmetry Breaking, and was continued and extended here. The problems of t quark jet identification and detection efficiency and the manner of rejection of background (especially from b quark jets) with realistic detectors then occupied much of the attention of the group. The subject of making precise measurements of parameters in the standard model at SSC energies is briefly examined. Then we delve into the Higgs sector, with an introduction to the neutral Higgs of the standard model together with its production cross-sections in various processes and the corresponding potential backgrounds. A similar, though briefer, discussion for a charged Higgs boson (outside the Standard Model) follows. The heart of the work on identifying and reconstructing the t and then the Higgs boson in the face of backgrounds is discussed. The problems with semileptonic decays, low energy jet fragments, mass resolution, and b-t discrimination all come to the fore. We have tried to make a serious step here towards a realistic assessment of the problems entailed in pulling a signal out of the background, including a rough simulation of calorimeter-detector properties. 25 references.

  14. Multiple-scattering formalism beyond the quasistatic approximation: Analyzing resonances in plasmonic chains

    DEFF Research Database (Denmark)

    de Lasson, Jakob Rosenkrantz; Kristensen, Philip Trøst; Mørk, Jesper

    2012-01-01

    We present a multiple-scattering formalism for simulating scattering of electromagnetic waves on spherical inhomogeneities in 3D. The formalism is based on the Lippmann-Schwinger equation and the electromagnetic Green's tensor and applies an expansion of the electric field on spherical wavefuncti...... wavefunctions. As an example, we analyze localized surface plasmons in chains of Ag spheres, and show how the resonances of such systems depend sensitively on the polarization of the incoming field, the spacing between the particles and the number of particles in the chain....

  15. Higgs boson couplings to bosons with the ATLAS detector: Run 1 legacy

    Science.gov (United States)

    Petit, E.; Atlas Collaboration

    2016-07-01

    The final ATLAS measurements of Higgs boson production and couplings in the decay channels H → ZZ^{(*)} → ℓℓℓℓ , H → γγ and H → WW(*) → ℓ νℓ ν are presented, based on the run 1 of the LHC. The analyses are optimised to measure the number of observed Higgs boson decays divided by the corresponding Standard Model predictions for individual Higgs boson production processes. Total, fiducial and differential cross-sections are also measured. No significant deviations from the predictions of the Standard Model are found.

  16. Black holes evaporation and big mass particle (maximon, intermediate boson) creation in nonstationary universe

    International Nuclear Information System (INIS)

    This chapter considers the process of creation of particles with maximally big masses (maximons, intermediate bosons) in the nonstationary Universe within the framework of neutral and charged scalar field theory. The conclusions of the matter creation model for real particles (resonances) and hypothetical particles (maximons, friedmons, intermediate bosons) are analyzed. It is determined that if the mechanism of maximon's creation exists, then these particles must be stable. The maximons could be the final states of decaying black holes. A possible mechanism of cosmic ray creation as a result of ''vacuum'' generation of known unstable particles is discussed. The limits upon the mass and the life time of intermediate bosons are calculated. It is demonstrated that the creation of masses greater than 10 GeV, and with life times less than 10-24 sec and quantity of elementary particles greater than 100 are in contradiction with the particle creation mechanism and the experimental mass density in the Universe. The formalism of the examined method and its vacuum properties are discussed in an appendix

  17. The future (and past) of quantum theory after the Higgs boson: a quantum-informational viewpoint.

    Science.gov (United States)

    Plotnitsky, Arkady

    2016-05-28

    Taking as its point of departure the discovery of the Higgs boson, this article considers quantum theory, including quantum field theory, which predicted the Higgs boson, through the combined perspective of quantum information theory and the idea of technology, while also adopting anon-realistinterpretation, in 'the spirit of Copenhagen', of quantum theory and quantum phenomena themselves. The article argues that the 'events' in question in fundamental physics, such as the discovery of the Higgs boson (a particularly complex and dramatic, but not essentially different, case), are made possible by the joint workings of three technologies: experimental technology, mathematical technology and, more recently, digital computer technology. The article will consider the role of and the relationships among these technologies, focusing on experimental and mathematical technologies, in quantum mechanics (QM), quantum field theory (QFT) and finite-dimensional quantum theory, with which quantum information theory has been primarily concerned thus far. It will do so, in part, by reassessing the history of quantum theory, beginning with Heisenberg's discovery of QM, in quantum-informational and technological terms. This history, the article argues, is defined by the discoveries of increasingly complex configurations of observed phenomena and the emergence of the increasingly complex mathematical formalism accounting for these phenomena, culminating in the standard model of elementary-particle physics, defining the current state of QFT. PMID:27091170

  18. Small firms' formalization: The stick treatment

    OpenAIRE

    De Giorgi, Giacomo; Ploenzke, Matthew; Rahman, Aminur

    2015-01-01

    Firm informality is pervasive throughout the developing world, Bangladesh being no exception. The informal status of many firms substantially reduces the tax basis and therefore impacts the provision of public goods. The literature on encouraging formalization has predominantly focused on reducing the direct costs of formalization and has found negligible impacts of such policies. This pap...

  19. Multifractal formalism and anisotropic selfsimilar functions

    Science.gov (United States)

    Ben Slimane, Mourad

    1998-09-01

    In this paper we prove that the conjectures of Frisch and Parisi and Arneodo et al. (called the multifractal formalism for functions) may fail for some non-homogeneous selfsimilar functions on [open face R]2. In these cases, we compute the correct spectrum of singularities and we show how the multifractal formalism must be modified.

  20. Hamilton-Jacobi formalism for linearized gravity

    Energy Technology Data Exchange (ETDEWEB)

    Bertin, M C [CMCC, Universidade Federal do ABC, Rua Santa Adalia, 166, Santo Andre, SP (Brazil); Pimentel, B M; Valcarcel, C E [Instituto de Fisica Teorica, UNESP, Sao Paulo State University, PO Box 70532-2, 01156-970, Sao Paulo, SP (Brazil); Zambrano, G E R, E-mail: mario.bertin@ufabc.edu.br, E-mail: pimentel@ift.unesp.br, E-mail: valcarcel@ift.unesp.br, E-mail: gramos@udenar.edu.co [Departamento de Fisica, Universidad de Narino, Calle 18 Carrera 50, San Juan de Pasto, Narino (Colombia)

    2011-09-07

    In this work, we study the theory of linearized gravity via the Hamilton-Jacobi formalism. We make a brief review of this theory and its Lagrangian description, as well as a review of the Hamilton-Jacobi approach for singular systems. Then, we apply this formalism to analyze the constraint structure of the linearized gravity in instant- and front-form dynamics.

  1. Formal Engineering Hybrid Systems: Semantic Underpinnings

    NARCIS (Netherlands)

    Bujorianu, M.C.; Bujorianu, L.M.

    2008-01-01

    In this work we investigate some issues in applying formal methods to hybrid system development and develop a categorical framework. We study the themes of stochastic reasoning, heterogeneous formal specification and retrenchment. Hybrid systems raise a rich pallets of aspects that need to be invest

  2. Restorative Practices as Formal and Informal Education

    Science.gov (United States)

    Carter, Candice C.

    2013-01-01

    This article reviews restorative practices (RP) as education in formal and informal contexts of learning that are fertile sites for cultivating peace. Formal practices involve instruction about response to conflict, while informal learning occurs beyond academic lessons. The research incorporated content analysis and a critical examination of the…

  3. DNA expressions - A formal notation for DNA

    NARCIS (Netherlands)

    Vliet, Rudy van

    2015-01-01

    We describe a formal notation for DNA molecules that may contain nicks and gaps. The resulting DNA expressions denote formal DNA molecules. Different DNA expressions may denote the same molecule. Such DNA expressions are called equivalent. We examine which DNA expressions are minimal, which

  4. General Formalism for the BRST Symmetry

    International Nuclear Information System (INIS)

    Abstract In this paper we will discuss Faddeev—Popov method for gauge theories with a general form of gauge symmetry in an abstract way. We will then develope a general formalism for dealing with the BRST symmetry. This formalism will make it possible to analyse the BRST symmetry for any theory. (physics of elementary particles and fields)

  5. Does (In)Formal Learning Enhance Employability?

    Science.gov (United States)

    van der Heijden, Beatrice I.J.M.; Boon, Jo; van der Klink, Marcel R.; Meys, Ely

    2008-01-01

    Not much is known about the actual contribution of informal learning to employability over and above formal learning activities. This paper presents findings of a research project among university staff members and is aimed to determine the contribution of formal and informal learning activities in the light of future career potential. Findings…

  6. Acrylates and methacrylates of formal-glycerine

    International Nuclear Information System (INIS)

    Present article is devoted acrylates and methacrylates of formal-glycerine. The formal-glycerine was obtained in the form of mixture of isomers 1.2 and 1.3 from glycerine and paraform with hydrochloric acid. The structure of obtained acrylates and methacrylates is studied by means of molecular refraction, element analysis and infrared spectroscopy.

  7. A Conceptual Formalization of Crosscutting in AOSD

    NARCIS (Netherlands)

    Berg, van den K.G.; Conejero, J.M.

    2005-01-01

    We propose a formalization of crosscutting based on a conceptual framework for AOSD. Crosscutting is clearly distinguished from the related concepts scattering and tangling. The definitions of these concepts are formalized and visualized with matrices and matrix operations. This allows more precise

  8. Formalizing Evaluation in Music Information Retrieval

    DEFF Research Database (Denmark)

    Sturm, Bob L.

    2013-01-01

    We develop a formalism to disambiguate the evaluation of music information retrieval systems. We define a ``system,'' what it means to ``analyze'' one, and make clear the aims, parts, design, execution, interpretation, and assumptions of its ``evaluation.'' We apply this formalism to discuss the...

  9. A computational formalization for partial evaluation

    DEFF Research Database (Denmark)

    Hatcliff, John; Danvy, Olivier

    1996-01-01

    We formalize a partial evaluator for Eugenio Moggi's computational metalanguage. This formalization gives an evaluation-order independent view of binding-time analysis and program specialization, including a proper treatment of call unfolding. It also enables us to express the essence of `control...

  10. The Formal Specifications for Protocols of Decoders

    Institute of Scientific and Technical Information of China (English)

    YUAN Meng-ting; WU Guo-qing; SHU Feng-di

    2004-01-01

    This paper presents a formal approach, FSPD (Formal Specifications for Protocols of Decoders), to specify decoder communication protocols. Based on axiomatic, FSPD is a precise language with which programmers could use only one suitable driver to handle various types of decoders. FSPD is helpful for programmers to get high adaptability and reusability of decoder-driver software.

  11. A computational formalization for partial evaluation

    DEFF Research Database (Denmark)

    Hatcliff, John; Danvy, Olivier

    1997-01-01

    We formalize a partial evaluator for Eugenio Moggi's computational metalanguage. This formalization gives an evaluation-order independent view of binding-time analysis and program specialization, including a proper treatment of call unfolding. It also enables us to express the essence of `control...

  12. Neutral Higgs boson search at Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Wei-Ming; /LBL, Berkeley

    2004-11-01

    The authors review searches for neutral Higgs Boson performed by the CDF and D0 collaborations using approximately 200 pb{sup -1} of the dataset accumulated from p{bar p} collisions at the center-of-mass energy of 1.96 TeV. No signals are found and limits on the Standard Model (SM) Higgs or SM-like Higgs production cross section times branching ratio and couplings of the Higgs boson in MSSM are presented, including the future prospects of discovery Higgs at the end of Run II.

  13. Bosonic superconformal algebras from hamiltonian reduction

    International Nuclear Information System (INIS)

    Hamiltonian reduction of WZW theories involving constraints with half integer conformal weight is analyzed. The reduced system can be described in terms of an effective action that corresponds to a generalized Toda system. To obtain this action, the constraints must be imposed on an enlarged phase space that includes weight 1/2 bosons in addition to the WZW degrees of freedom. An example is worked out for which the chiral algebra consists of a bosonic version of the uN extended superconformal algebra. A Gauss decomposition of the WZW field leads to a hybrid free field realization of these algebras. (orig.)

  14. Slepton production from gauge boson fusion

    CERN Document Server

    Choudhury, D; Huitu, K; Konar, P; Moretti, S; Mukhopadhyaya, B; Choudhury, Debajyoti; Datta, Anindya; Huitu, Katri; Konar, Partha; Moretti, Stefano; Mukhopadhyaya, Biswarup; 10.1103/PhysRevD.68.075007

    2003-01-01

    We emphasise that charged slepton pairs produced via vector-boson fusion along with two high-mass, high-$p_T$ forward/backward jets (in two opposite hemispheres) can have a higher production cross-section for heavy slepton masses than that from conventional Drell-Yan production at a hadronic collider like the LHC. We analyse the signal and leading backgrounds in detail in the minimal supersymmetric standard model with conserved baryon and lepton numbers. Our investigation reveals that the mass reach of the vector-boson fusion channel is certainly an improvement over the scope of the Drell-Yan mode.

  15. Lepton flavor violation with light vector bosons

    Science.gov (United States)

    Heeck, Julian

    2016-07-01

    New sub-GeV vector bosons with couplings to muons but not electrons have been discussed in order to explain the muon's magnetic moment, the gap of high-energy neutrinos in IceCube or the proton radius puzzle. If such a light Z‧ not only violates lepton universality but also lepton flavor, as expected for example from the recent hint for h → μτ at CMS, the two-body decay mode τ → μZ‧ opens up and for MZ‧ vector bosons with lepton-flavor-violating couplings.

  16. Gauge boson production at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Cecilia E Gerber

    2003-01-15

    We present measurements on gauge boson production from data taken during 1994-1996 by the D0 and CDF detectors: the differential production cross section of the W boson as a function of the transverse momentum [1,2], the ratio of W and Z differential cross sections [3,4], direct photon cross-sections at {radical}s = 630 and 1800 GeV [5,6], and studies of Drell-Yan production [7,8]. All measurements are in good agreement with currently available theoretical predictions in most of the measured kinematic range.

  17. Higgs boson decays in the Complex MSSM

    OpenAIRE

    Williams, K. E.; Weiglein, G.

    2007-01-01

    The analysis of the Higgs search results at LEP showed that a part of the MSSM parameter space with non-zero complex phases could not be excluded, where the lightest neutral Higgs boson, h_1, has a mass of only about 45 GeV and the second lightest neutral Higgs boson, h_2, has a sizable branching fraction into a pair of h_1 states. Full one-loop results for the Higgs cascade decay h_2 --> h_1 h_1 are presented and combined with two-loop Higgs propagator corrections taken from the program Feyn...

  18. Higgs boson mass from gauge invariant operators

    CERN Document Server

    Jora, Renata

    2016-01-01

    We make the assumption that the vacuum correlators of the gauge invariant kinetic term of the Higgs doublet are the same before and after the spontaneous symmetry breaking of the theory. Based on this we determine the mass of the standard model Higgs boson at $m_h \\approx 125.07$ GeV by considering one loop and the most relevant two loop corrections. This result might suggest that there is a single Higgs boson doublet that contributes to the electroweak symmetry breaking.

  19. Lepton flavor violation with light vector bosons

    Science.gov (United States)

    Heeck, Julian

    2016-07-01

    New sub-GeV vector bosons with couplings to muons but not electrons have been discussed in order to explain the muon's magnetic moment, the gap of high-energy neutrinos in IceCube or the proton radius puzzle. If such a light Z‧ not only violates lepton universality but also lepton flavor, as expected for example from the recent hint for h → μτ at CMS, the two-body decay mode τ → μZ‧ opens up and for MZ‧ year-old ARGUS limits. We discuss the general prospects and motivation of light vector bosons with lepton-flavor-violating couplings.

  20. Search for Charged Higgs Bosons at LEP

    CERN Document Server

    Achard, P; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Baldew, S V; Banerjee, S; Banerjee, Sw; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiefari, G; Cifarelli, Luisa; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; van Dalen, J A; De Asmundis, R; Déglon, P L; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau, D; Duda, M; Echenard, B; Eline, A; El-Hage, A; El-Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Guida, M; van Gulik, R; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Käfer, D; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kräber, M H; Krämer, R W; Krüger, A; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Levtchenko, M; Levchenko, P M; Li, C; Likhoded, S; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Luci, C; Luminari, L; Lustermann, W; Ma Wen Gan; Malgeri, L; Malinin, A; Maña, C; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Novák, T; Nowak, H; Ofierzynski, R A; Organtini, G; Pal, I; Palomares, C; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofev, D; Prokofiev, D O; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P A; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosenbleck, C; Rosier-Lees, S; Roth, S; Rubio, J A; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Schäfer, C; Shchegelskii, V; Schopper, Herwig Franz; Schotanus, D J; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A V; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, Ludwig; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Ulbricht, J; Valente, E; Van de Walle, R T; Vásquez, R; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, Gert M; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, Q; Wang, X L; Wang, Z M; Weber, M; Wienemann, P; Wilkens, H; Wynhoff, S; Xia, L; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhao, J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zichichi, A; Zimmermann, B; Zöller, M

    2003-01-01

    A search for pair-produced charged Higgs bosons is performed with the L3 detector at LEP using data collected at centre-of-mass energies between 189 and 209GeV, corresponding to an integrated luminosity of 629.4/pb. Decays into a charm and a strange quark or into a tau lepton and its neutrino are considered. No significant excess is observed and lower limits on the mass of the charged Higgs boson are derived at the 95% confidence level. They vary from 76.5 to 82.7GeV, as a function of the H->tv branching ratio.

  1. Z Boson Pair-Production at LEP

    CERN Document Server

    Achard, P; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Baldew, S V; Banerjee, S; Banerjee, Sw; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiefari, G; Cifarelli, Luisa; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; van Dalen, J A; De Asmundis, R; Déglon, P L; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau, D; Duda, M; Echenard, B; Eline, A; El-Hage, A; El-Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Guida, M; van Gulik, R; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Käfer, D; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kräber, M H; Krämer, R W; Krüger, A; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Levtchenko, M; Levchenko, P M; Li, C; Likhoded, S; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Luci, C; Luminari, L; Lustermann, W; Ma Wen Gan; Malgeri, L; Malinin, A; Maña, C; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Novák, T; Nowak, H; Ofierzynski, R A; Organtini, G; Pal, I; Palomares, C; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofev, D; Prokofiev, D O; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P A; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosier-Lees, S; Roth, S; Rosenbleck, C; Roux, B; Rubio, J A; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Schäfer, C; Shchegelskii, V; Schopper, Herwig Franz; Schotanus, D J; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A V; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, Ludwig; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Ulbricht, J; Valente, E; Van de Walle, R T; Vásquez, R; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, Gert M; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, Q; Wang, X L; Wang, Z M; Weber, M; Wienemann, P; Wilkens, H; Wynhoff, S; Xia, L; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhao, J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zichichi, A; Zimmermann, B; Zöller, M

    2003-01-01

    Events stemming from the pair-production of Z bosons in e^+e^- collisions are studied using 217.4 pb^-1 of data collected with the L3 detector at centre-of-mass energies from 200 GeV up to 209 GeV. The special case of events with b quarks is also investigated. Combining these events with those collected at lower centre-of-mass energies, the Standard Model predictions for the production mechanism are verified. In addition, limits are set on anomalous couplings of neutral gauge bosons and on effects of extra space dimensions.

  2. Searches for BSM Higgs Bosons with ATLAS

    CERN Document Server

    Navarro, Gabriela; The ATLAS collaboration

    2015-01-01

    The discovery of a Higgs-like boson with a mass of about 125GeV has prompted the question of whether or not this particle is part of a much larger and more complex Higgs sector than that envisioned in the Standard Model. In this talk, the current results from the ATLAS Experiment regarding Beyond-the-Standard Model (BSM) Higgs hypothesis tests are outlined. Searches for additional Higgs bosons are presented and interpreted in well-motivated BSM Higgs frameworks, such as two-Higgs-doublet Models and the Minimal Supersymmetric Standard Model.

  3. The discovery of the intermediate vector bosons

    International Nuclear Information System (INIS)

    The discovery of the intermediate vector bosons in 1983 at CERN marked the culmination of a long effort to unify the theory of weak and electromagnetic forces. Here a brief outline of development of the electroweak theory which unifies these forces is given first. Its essential feature is the prediction of the existence of the W+- and Z0 bosons with rest masses of about ninety times the proton mass and lifetimes around 10-24s. Then the experimental methods used at CERN to produce and to detect these very massive and short-lived particles are described. (author)

  4. Left and right handedness of fermions and bosons

    International Nuclear Information System (INIS)

    It is shown, by using Grassmann space to describe the internal degrees of freedom of fermions and bosons, that the Weyl-like equation exists not only for massless fermions but also for massless vector bosons. The corresponding states have well defined helicity and handedness. It is also shown that spinors and vector bosons interact only if both are of the same handedness. (author)

  5. Momentum-space calculation of four-boson recombination

    OpenAIRE

    Deltuva, A.

    2012-01-01

    The system of four identical bosons with large two-boson scattering length is described using momentum-space integral equations for the four-particle transition operators. The creation of Efimov trimers via ultracold four-boson recombination is studied. The universal behavior of the recombination rate is demonstrated.

  6. Intrinsic Heating and Cooling in Adiabatic Processes for Bosons in Optical Lattices

    International Nuclear Information System (INIS)

    We show that by raising the lattice ''adiabatically'' as in many current optical lattice experiments on bosons, even though the temperature may decrease initially, it will eventually rise linearly with lattice height, taking the system farther away from quantum degeneracy. This increase has nothing to do with the entropy of the bulk Mott phase and is caused by the adiabatic compression of the mobile atoms between Mott layers. Our studies show that one can reverse the temperature rise to reach quantum degeneracy by adiabatic expansion, which can be achieved by a variety of methods

  7. Financing electricity expansion

    International Nuclear Information System (INIS)

    Expansion of electricity supply is associated with economic development. The installation and enlargement of power systems in developing countries entails a huge financial burden, however. Energy consumers in such countries must pay not only for supplies but for the cost of raising the capital for expansion on the international markets. Estimates are presented for the capital expenditure for electricity supply over the period 1990 to 2020 for the major world regions, using approximations for the cost of plant and capital and for the returns earned. These data lead to the conclusion that the five regions with the lowest per capita incomes are those which will need the major part of the capital expenditure and the highest percentage of external finance. (6 tables) (UK)

  8. Operator product expansion algebra

    International Nuclear Information System (INIS)

    The Operator Product Expansion (OPE) is a theoretical tool for studying the short distance behaviour of products of local quantum fields. Over the past 40 years, the OPE has not only found widespread computational application in high-energy physics, but, on a more conceptual level, it also encodes fundamental information on algebraic structures underlying quantum field theories. I review new insights into the status and properties of the OPE within Euclidean perturbation theory, addressing in particular the topics of convergence and ''factorisation'' of the expansion. Further, I present a formula for the ''deformation'' of the OPE algebra caused by a quartic interaction. This formula can be used to set up a novel iterative scheme for the perturbative computation of OPE coefficients, based solely on the zeroth order coefficients (and renormalisation conditions) as initial input.

  9. Expansion at Olympic Dam

    International Nuclear Information System (INIS)

    The Olympic Dam orebody is the 6th largest copper and the single largest uranium orebody in the world. Mine production commenced in June 1988, at an annual production rate of around 45,000 tonnes of copper and 1,000 tonnes of uranium. Western Mining Corporation announced in 1996 a proposed $1.25 billion expansion of the Olympic Dam operation to raise the annual production capacity of the mine to 200,000 tonnes of copper, approximately 3,700 tonnes of uranium, 75,000 ounces of gold and 950,000 ounces of silver by 2001. Further optimisation work has identified a faster track expansion route, with an increase in the capital cost to $1.487 billion but improved investment outcome, a new target completion date of end 1999, and a new uranium output of 4,600 tonnes per annum from that date

  10. Expansion of Hanford concrete

    International Nuclear Information System (INIS)

    This report presents results of measurements of thermal expansion of concrete cores from Hanford, Washington facilities, and concrete cast at the Construction Technology Laboratories of Portland Cement Association (CTL/PCA). Thermal expansion was measured from room temperature to 16000F on 0.5 x 3.0-in. specimens heated at a rate of 100F/min. Specimens were cored from concrete cylinders cast at CTL/PCA in 1975 and 1977, and from cylindrical cores taken from the Purex Building and Waste Tank Farms at the Hanford, Washington complex. A total of 14 specimens were tested: eight tests on CTL/PCA cast concrete, two tests on material from the Purex Building, and four tests on Waste Tank Farms concrete. All tests were conducted using a commercially built dilatometer of high strain resolution

  11. On Fitting a Formal Method into Practice

    DEFF Research Database (Denmark)

    Gmehlich, Rainer; Grau, Katrin; Hallerstede, Stefan;

    2011-01-01

    The development of the Event-B formal method and the supporting tools Rodin and ProB was guided by practical experiences with the B-Method, the Z specification notation, VDM and similar practical formal methods. The case study discussed in this article - a cruise control system - is a serious test...... of industrial use. We report on where Event-B and its tools have succeeded, where they have not. We also report on advances that were inspired by the case study. Interestingly, the case study was not a pure formal methods problem. In addition to Event-B, it used Problem Frames for capturing...... requirements. The interaction between the two proved to be crucial for the success of the case study. The heart of the problem was tracing informal requirements from Problem Frames descriptions to formal Event-B models. To a large degree, this issue dictated the approach that had to be used for formal...

  12. IKEA's International Expansion

    OpenAIRE

    Harapiak, Clayton

    2013-01-01

    This case concerns a global retailing firm that is dealing with strategic management and marketing issues. Applying a scenario of international expansion, this case provides a thorough analysis of the current business environment for IKEA. Utilizing a variety of methods (e.g. SWOT, PESTLE, McKinsey Matrix) the overall objective is to provide students with the opportunity to apply their research skills and knowledge regarding a highly competitive industry to develop strategic marketing strateg...

  13. China petrochemical expansion progressing

    International Nuclear Information System (INIS)

    This paper reports on China's petrochemical expansion surge which is picking up speed. A worldscale petrochemical complex is emerging at Shanghai with an eye to expanding China's petrochemical exports, possibly through joint ventures with foreign companies, China Features reported. In other action, Beijing and Henan province have approved plans for a $1.2 billion chemical fibers complex at the proposed Luoyang refinery, China Daily reported

  14. Ultraprecise thermal expansion measurements of seven low expansion materials

    Science.gov (United States)

    Berthold, J. W., III; Jacobs, S. F.

    1976-01-01

    We summarize a large number of ultraprecise thermal expansion measurements made on seven different low expansivity materials. Expansion coefficients in the -150-300 C temperature range are shown for Owens-Illinois Cer-Vit C-101, Corning ULE 7971 (titanium silicate) and fused silica 7940, Heraeus-Schott Zerodur low-expansion material and Homosil fused silica, Universal Cyclops Invar LR-35, and Simonds Saw and Steel Super Invar.

  15. Quality of potential harmonics expansion method for dilute Bose–Einstein condensate

    Indian Academy of Sciences (India)

    Anasuya Kundu; Barnali Chakrabarti

    2007-09-01

    We present and examine an approximate but ab initio many-body approach, viz., potential harmonics expansion method (PHEM), which includes two-body correlations for dilute Bose–Einstein condensates. Comparing the total ground state energy for three trapped interacting bosons calculated in PHEM with the exact energy, the new method is shown to be very good in the low density limit which is necessary for achieving Bose–Einstein condensation experimentally.

  16. Harmonic expansion of the effective potential in Functional Renormalization Group at finite chemical potential

    CERN Document Server

    Barnafoldi, G G; Posfay, P

    2016-01-01

    In this paper we propose a method to study the Functional Renormalization Group at finite chemical potential. The method consists of mapping the FRG equations within the Fermi surface into a differential equation defined on a rectangle with zero boundary conditions. To solve this equation we use an expansion of the potential in a harmonic basis. With this method we determined the phase diagram of a simple Yukawa-type model; as expected, the bosonic fluctuations decrease the strength of the transition.

  17. Exact Solution for Jaynes-Cummings Model with Bosonic Field Nonlinearity and Strong Boson-Fermion Coupling

    Institute of Scientific and Technical Information of China (English)

    YANG Jin; YU Wan-Lun; XIANG An-Ping

    2006-01-01

    We use Lewis-Riesenfeld invariant approach to treat the modified Jaynes-Cummings models involving any forms of nonlinearty of the bosonic field when strong boson-fermion couplings are nilpotent Grassmann valued. The general state functions, time evolution operator and the time-evolution expressions for both the bosonic number and the fermionic number are presented.

  18. Asymptotic expansion of the solution of a Cauchy problem for singularly perturbed differential-operational nonlinear equation

    International Nuclear Information System (INIS)

    A formal asymptotic expansion of a solution of the initial problem for a singularly perturbed differential-operational nonlinear equation in a small parameter has been constructed in the critical case. Splash functions of and boundary functions have been estimated of found and assessment of the residual member of the expansion has been obtained

  19. Search for an Invisibly Decaying Higgs Boson Produced via Vector Boson Fusion with ATLAS

    CERN Document Server

    Bassalat, Ahmed; The ATLAS collaboration

    2015-01-01

    The recently discovered Higgs boson at a mass 125 GeV provides an excellent tool to probe beyond the Standard Model physics. Many extensions of the Standard Model predict the decay of the Higgs boson into weakly interacting or neutral particles which do not interact with the detector, that could be candidates for dark matter. Using proton-proton collision data collected by the ATLAS detector during Run 1, searches have been performed for an invisibly decaying Higgs boson in three production channels: via vector boson fusion (VBF). An upper bound of 0.28 is set on the branching fraction of H -> invisible at 95% confidence level, where the expected upper limit is 0.31. The results are interpreted in models of Higgs-portal dark matter and of supersymmetry with a compressed mass spectrum.

  20. Distinguishing Various Models of the 125 GeV Boson in Vector Boson Fusion

    CERN Document Server

    Chang, Jung; Tseng, Po-Yan; Yuan, Tzu-Chiang

    2012-01-01

    The hint of a new particle around 125 GeV at the LHC through the decay modes of diphoton and a number of others may point to quite a number of possibilities. While at the LHC the dominant production mechanism in the standard model is via the gluon fusion process, the alternative vector boson fusion is more sensitive to electroweak symmetry breaking through the $WWh$ and $ZZh$ couplings and therefore can be used to probe for models beyond the standard model. In this work, using the well known dijet-tagging technique to single out the vector boson fusion mechanism, we investigate its capability to discriminate a number of models, including the standard model Higgs boson, fermiophobic Higgs boson, Randall-Sundrum radion, inert-doublet-Higgs model, two-Higgs-doublet model, and selective benchmark points of MSSM and NMSSM.