Matter inflation with A_4 flavour symmetry breaking
Antusch, Stefan
2013-01-01
We discuss model building in tribrid inflation, which is a framework for realising inflation in the matter sector of supersymmetric particle physics models. The inflaton is a D-flat combination of matter fields, and inflation ends by a phase transition in which some Higgs field obtains a vacuum expectation value. We first describe the general procedure for implementing tribrid inflation in realistic models of particle physics that can be applied to a wide variety of BSM particle physics models around the GUT scale. We then demonstrate how the procedure works for an explicit lepton flavour model based on an A_4 family symmetry. The model is both predictive and phenomenologically viable, and illustrates how tribrid inflation connects cosmological and particle physics parameters. In particular, it predicts a relation between the neutrino Yukawa coupling and the running of the spectral index alpha_s. We also show how topological defects from the flavour symmetry breaking can be avoided automatically.
Matter inflation with A4 flavour symmetry breaking
International Nuclear Information System (INIS)
We discuss model building in tribrid inflation, which is a framework for realising inflation in the matter sector of supersymmetric particle physics models. The inflaton is a D-flat combination of matter fields, and inflation ends by a phase transition in which some Higgs field obtains a vacuum expectation value. We first describe the general procedure for implementing tribrid inflation in realistic models of particle physics that can be applied to a wide variety of BSM particle physics models around the GUT scale. We then demonstrate how the procedure works for an explicit lepton flavour model based on an A4 family symmetry. The model is both predictive and phenomenologically viable, and illustrates how tribrid inflation connects cosmological and particle physics parameters. In particular, it predicts a relation between the neutrino Yukawa coupling and the running of the spectral index αs. We also show how topological defects from the flavour symmetry breaking can be avoided automatically
LFV and Dipole Moments in Models with A4 Flavour Symmetry
Merlo, Luca
2009-01-01
It is presented an analysis on lepton flavour violating transitions, leptonic magnetic dipole moments and electric dipole moments in a class of models characterized by the flavour symmetry A4 x Z3 x U(1)_FN, whose choice is motivated by the approximate Tri-Bimaximal mixing observed in neutrino oscillations. A low-energy effective Lagrangian is constructed, where these effects are dominated by dimension six operators, suppressed by the scale M of new physics. All the flavour breaking effects are universally described by the vacuum expectation values of a set of spurions. Two separate cases, a supersymmetric and a general one, are described. An upper limit on the reactor angle of a few percent is concluded.
A neutrino mixing model based on an $A_4\\times Z_3\\times Z_4$ flavour symmetry
Ky, Nguyen Anh; Van, Nguyen Thi Hong
2016-01-01
A model of a neutrino mixing with an $A_4\\times Z_3\\times Z_4$ flavour symmetry is suggested. In addition to the standard model fields, the present model contains six new fields which transform under different representations of $A_4\\times Z_3\\times Z_4$. The model is constructed to slightly deviate from a tri-bi-maximal model in agreement with the current experimental data, thus, all analysis can be done in the base of the perturbation method. Within this model, as an application, a relation between the mixing angles ($\\theta_{12}, \\theta_{23}, \\theta_{13}$) and the Dirac CP-violation phase ($\\delta_{CP}$) is established. This relation allows a prediction of $\\delta_{CP}$ and the Jarlskog parameter ($J_{CP}$). The predicted value $\\delta_{CP}$ is in the 1$\\sigma$ region of the global fit for both the normal- and inverse neutrino mass ordering and gives $J_{CP}$ to be within the bound $|J_{CP}|\\leq 0.04$. For an illustration, the model is checked numerically and gives values of the neutrino masses (of the ord...
Flavour from accidental symmetries
Energy Technology Data Exchange (ETDEWEB)
Ferretti, Luca [SISSA/ISAS and INFN, I-34013 Trieste (Italy); King, Stephen F. [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom); Romanino, Andrea [SISSA/ISAS and INFN, I-34013 Trieste (Italy)
2006-11-15
We consider a new approach to fermion masses and mixings in which no special 'horizontal' dynamics is invoked to account for the hierarchical pattern of charged fermion masses and for the peculiar features of neutrino masses. The hierarchy follows from the vertical, family-independent structure of the model, in particular from the breaking pattern of the Pati-Salam group. The lightness of the first two fermion families can be related to two family symmetries emerging in this context as accidental symmetries.
Strong coupling, discrete symmetry and flavour
Abel, Steven
2010-01-01
We show how two principles - strong coupling and discrete symmetry - can work together to generate the flavour structure of the Standard Model. We propose that in the UV the full theory has a discrete flavour symmetry, typically only associated with tribimaximal mixing in the neutrino sector. Hierarchies in the particle masses and mixing matrices then emerge from multiple strongly coupled sectors that break this symmetry. This allows for a realistic flavour structure, even in models built around an underlying grand unified theory. We use two different techniques to understand the strongly coupled physics: confinement in N=1 supersymmetry and the AdS/CFT correspondence. Both approaches yield equivalent results and can be represented in a clear, graphical way where the flavour symmetry is realised geometrically.
On the origin of neutrino flavour symmetry
King, Stephen F
2009-01-01
We study classes of models which are based on some discrete family symmetry which is completely broken such that the observed neutrino flavour symmetry emerges indirectly as an accidental symmetry. For such "indirect" models we discuss the D-term flavon vacuum alignments which are required for such an accidental flavour symmetry consistent with tri-bimaximal lepton mixing to emerge. We identify large classes of suitable discrete family symmetries, namely the $\\Delta(3n^2)$ and $\\Delta(6n^2)$ groups, together with other examples such as $Z_7\\rtimes Z_3$. In such indirect models the implementation of the type I see-saw mechanism is straightforward using constrained sequential dominance. However the accidental neutrino flavour symmetry may be easily violated, for example leading to a large reactor angle, while maintaining accurately the tri-bimaximal solar and atmospheric predictions.
Extracting gamma Through Flavour-Symmetry Strategies
Fleischer, Robert
2002-01-01
A brief overview of flavour-symmetry strategies to extract the angle gamma of the unitarity triangle is given, focusing on B --> pi K modes and the B_d --> pi^+ pi^-, B_s --> K^+ K^- system. We discuss also a variant of the latter approach for the e^+ e^- B-factories, where B_s --> K^+ K^- is replaced by B_d --> pi^{+/-} K^{+/-}.
Bimaximal Neutrino Mixing with Discrete Flavour Symmetries
Merlo, Luca
2011-01-01
In view of the fact that the data on neutrino mixing are still compatible with a situation where Bimaximal mixing is valid in first approximation and it is then corrected by terms of order of the Cabibbo angle, we present examples where these properties are naturally realized. The models are supersymmetric in 4-dimensions and based on the discrete non-Abelian flavour symmetry S4.
Effective theories with broken flavour symmetry
International Nuclear Information System (INIS)
The work of Ovrut and Schnitzer on effective theories derived from a non Abelian Gauge Theory is generalised to include the physically interesting case of broken flavour symmetry. The calculations are performed at the 1-loop level. It is shown that at an intermediate stage in the calculations two distinct renormalised gauge coupling constants appear, one describing gauge field coupling to heavy particles and the other describing coupling to light particles. Appropriately modified Slavnov-Taylor identities are shown to hold. A simple alternative to the Ovrut-Schnitzer rules for calculating with effective theories is also considered
Lepton Flavour at the Electroweak Scale: A Complete A4 Model
Holthausen, Martin; Schmidt, Michael A
2012-01-01
Apparent regularities in fermion masses and mixings are often associated with physics at a high flavour scale, especially in the context of discrete flavour symmetries. One of the main reasons for that is that the correct vacuum alignment requires usually some high scale mechanism to be phenomenologically acceptable. Contrary to this expectation, we present in this paper a renormalizable radiative neutrino mass model with an A4 flavour symmetry in the lepton sector, which is broken at the electroweak scale. For that we use a novel way to achieve the VEV alignment via an extended symmetry in the flavon potential proposed before by two of the authors. We discuss various phenomenological consequences for the lepton sector and show how the remnants of the flavour symmetry suppress large lepton flavour violating processes. The model naturally includes a dark matter candidate, whose phenomenology we outline. Finally, we sketch possible extensions to the quark sector and discuss its implications for the LHC, especia...
SO(10) models with flavour symmetries: classification and examples
Ivanov, I. P.; Lavoura, L.
2016-10-01
Renormalizable SO(10) grand unified theory (GUT) models equipped with flavour symmetries are a popular framework for addressing the flavour puzzle. Usually, the flavour symmetry group has been an ad hoc choice, and no general arguments limiting this choice were known. In this paper, we establish the full list of flavour symmetry groups which may be enforced, without producing any further accidental symmetry, on the Yukawa-coupling matrices of an SO(10) GUT with arbitrary numbers of scalar multiplets in the {{10}}, \\bar{{{126}}}, and {{120}} representations of SO(10). For each of the possible discrete non-Abelian symmetry groups, we present examples of minimal models which do not run into obvious contradiction with the phenomenological fermion masses and mixings.
Neutrino masses and mixing: a flavour symmetry roadmap
Morisi, S
2012-01-01
Over the last ten years tri-bimaximal mixing has played an important role in modeling the flavour problem. We give a short review of the status of flavour symmetry models of neutrino mixing. We concentrate on non-Abelian discrete symmetries, which provide a simple way to account for the TBM pattern. We discuss phenomenological implications such as neutrinoless double beta decay, lepton flavour violation as well as theoretical aspects such as the possibility to explain quarks and leptons within a common framework, such as grand unified models.
Lepton-flavour violation in a Pati-Salam model with gauged flavour symmetry
Feldmann, Thorsten; Moch, Paul
2016-01-01
Combining Pati-Salam (PS) and flavour symmetries in a renormalisable setup, we devise a scenario which produces realistic masses for the charged leptons. Flavour-symmetry breaking scalar fields in the adjoint representations of the PS gauge group are responsible for generating different flavour structures for up- and down-type quarks as well as for leptons. The model is characterised by new heavy fermions which mix with the Standard Model quarks and leptons. In particular, the partners for the third fermion generation induce sizeable sources of flavour violation. Focusing on the charged-lepton sector, we scrutinise the model with respect to its implications for lepton-flavour violating processes such as $\\mu \\rightarrow e\\gamma$, $\\mu\\rightarrow 3e$ and muon conversion in nuclei.
Lepton Mixing Predictions from (Generalised) CP and Discrete Flavour Symmetry
Neder, Thomas
2015-01-01
An important class of flavour groups, that are subgroups of $U(3)$ and that predict experimentally viable lepton mixing parameters including Majorana phases, is the $\\Delta(6n^2)$ series. The most well-known member is $\\Delta(24)=S_4$. I present results of several extensive studies of lepton mixing predictions obtained in models with a $\\Delta(6n^2)$ flavour group that preserve either the full residual $Z_2\\times Z_2$ or a $Z_2$ subgroup for neutrinos and can include a generalised CP symmetry. Predictions include mixing angles and Dirac CP phase generally; and if invariance under a generalised CP symmetry is included, also Majorana phases. For this, the interplay of flavour group and generalised CP symmetry has to be studied carefully.
A U(2)^3 flavour symmetry in Supersymmetry
Sala, Filippo
2012-01-01
A U(2)^3 flavour symmetry acting on the first two generations of quarks partially explains the hierarchies of the yukawa couplings, and provides a natural embedding for Supersymmetry with heavier first two generations, where collider constraints are not in conflict with the requirement of naturalness and the SUSY CP problem is solved. Within this context a specific pattern of flavour symmetry breaking is considered. The K, B_d and B_s mixing amplitudes show a definite correlation that can resolve existing tensions in the CKM fit, pointing in this way to sbottom and gluino masses below about 1.5 TeV. Potentially sizeable contributions to both indirect and direct CP violation in B decays are allowed, even in the absence of flavour-blind phases. In case some effects are observed, the peculiar pattern in Delta(F) = 2 and Delta(B) = 1 observables may allow to distinguish between this and other models.
Neutrino Mixings and the S4 Discrete Flavour Symmetry
Bazzocchi, Federica
2012-01-01
Discrete non-Abelian Symmetries have been extensively used to reproduce the lepton mixings. In particular, the S4 group turned out to be suitable to describe predictive mixing patterns, such as the well-known Tri-Bimaximal and the Bimaximal schemes, which all represent possible first approximations of the experimental lepton mixing matrix. We review the main application of the S4 discrete group as a flavour symmetry, first dealing with the formalism and later with the phenomenological implications. In particular, we summarize the main features of flavour models based on S4, commenting on their ability in reproducing a reactor angle in agreement with the recent data and on their predictions for lepton flavour violating transitions.
The flavour problem and family symmetry beyond the Standard Model
Dziewit, Bartosz; Richter, Monika; Zając, Sebastian; Zrałek, Marek
2016-01-01
In the frame of two Higgs doublet model we try to explain the lepton masses and mixing matrix elements assuming that neutrinos are Dirac particles. Discrete family symmetry groups, which are subgroups of U(3) up to the 1025 order are considered. Like in the one Higgs Standard Model, we found that discrete family symmetries do not give satisfactory answer for this basic questions in the flavour problem.
S_3-flavour symmetry as realized in lepton flavour violating processes
Mondragón, A; Peinado, E
2007-01-01
A variety of lepton flavour violating effects related to the recent discovery of neutrino oscillations and mixings is here systematically discussed in terms of an S_3-flavour permutational symmetry. After a brief review of some relevant results on lepton masses and mixings, that had been derived in the framework of a Minimal S_3-Invariant Extension of the Standard Model, we derive explicit analytical expressions for the matrices of the Yukawa couplings and compute the branching ratios of some selected flavour changing neutral current (FCNC) processes, as well as, the contribution of the exchange of neutral flavour changing scalars to the anomaly of the muon's magnetic moment as functions of the masses of the charged leptons and the neutral Higgs bosons. We find that the S_3 x Z_2 flavour symmetry and the strong mass hierarchy of the charged leptons strongly suppress the FCNC processes in the leptonic sector well below the present experimental upper bounds by many orders of magnitude. The contribution of FCNC ...
Pulsars: Macro-nuclei with 3-flavour symmetry
Xu, Renxin
2015-01-01
A pulsar-like compact star is the rump left behind after a supernova where normal baryonic matter is intensely compressed by gravity, but the real state of such compressed baryonic matter is still not well understood because of the non-perturbative nature of the fundamental color interaction. We argue that pulsars could be of condensed matter of quark clusters, i.e., "quark-cluster stars" which distinguish from conventional neutron and quark stars. In comparison with 2-flavour symmetric micro-nuclei, a quark-cluster star could simply be considered as a macro-nucleus with 3-flavour symmetry. New research achievements both theoretical and observational are briefly presented.
The Symmetry behind Extended Flavour Democracy and Large Leptonic Mixing
Silva-Marcos, Joaquim I
2002-01-01
We show that there is a minimal discrete symmetry which leads to the extended flavour democracy scenario constraining the Dirac neutrino, the charged lepton and the Majorana neutrino mass term ($M_R$) to be all proportional to the democratic matrix, with all elements equal. In particular, this discrete symmetry forbids other large contributions to $M_R$, such as a term proportional to the unit matrix, which would normally be allowed by a $S_{3L}\\times S_{3R}$ permutation symmetry. This feature is crucial in order to obtain large leptonic mixing, without violating 't Hooft's, naturalness principle.
Flavour symmetry as a Spontaneously Broken Discrete Permutation Symmetry Embedded in Colour
Törnqvist, N A
1999-01-01
A new mechanism for breaking an internal symmetry spontaneously is discussed, which is intermediate between the Nambu-Goldstone and Wigner modes of symmetry breaking. Here the quark-antiquark sea takes the role of the vacuum of the Nambu-Goldstone case. Flavour symmetry becomes a discrete permutation symmetry of the valence quarks with respect to the sea quarks, which can be spontaneously broken without generation of massless Goldstone bosons.
Quark-flavour phenomenology of models with extended gauge symmetries
International Nuclear Information System (INIS)
Gauge invariance is one of the fundamental principles of the Standard Model of particles and interactions, and it is reasonable to believe that it also regulates the physics beyond it. In this thesis we have studied the theory and phenomenology of two New Physics models based on gauge symmetries that are extensions of the Standard Model group. Both of them are particularly interesting because they provide some answers to the question of the origin of flavour, which is still unexplained. Moreover, the flavour sector represents a promising field for the research of indirect signatures of New Physics, since after the first run of LHC we do not have any direct hint of it yet. The first model assumes that flavour is a gauge symmetry of nature, SU(3)3f, spontaneously broken by the vacuum expectation values of new scalar fields; the second model is based on the gauge group SU(3)c x SU(3)L x U(1)X, the simplest non-abelian extension of the Standard Model group. We have traced the complete theoretical building of the models, from the gauge group, passing through the nonanomalous fermion contents and the appropriate symmetry breakings, up to the spectra and the Feynman rules, with a particular attention to the treatment of the flavour structure, of tree-level Flavour Changing Neutral Currents and of new CP-violating phases. In fact, these models present an interesting flavour phenomenology, and for both of them we have analytically calculated the contributions to the ΔF=2 and ΔF=1 down-type transitions, arising from new tree-level and box diagrams. Subsequently, we have performed a comprehensive numerical analysis of the phenomenology of the two models. In both cases we have found very effective the strategy of first to identify the quantities able to provide the strongest constraints to the parameter space, then to systematically scan the allowed regions of the latter in order to obtain indications about the key flavour observables, namely the mixing parameters of the
Discrete Flavour Symmetries from the Heisenberg Group
Floratos, E G
2015-01-01
Non-abelian discrete symmetries are of particular importance in model building. They are mainly invoked to explain the various fermion mass hierarchies and forbid dangerous superpotential terms. In string models they are usually associated to the geometry of the compactification manifold and more particularly to the magnetised branes in toroidal compactifications. Motivated by these facts, in this note we propose a unified framework to construct representations of finite discrete family groups based on the automorphisms of the discrete and finite Heisenberg group. We focus in particular in the $PSL_2(p)$ groups which contain the phenomenologically interesting cases.
Discrete flavour symmetries from the Heisenberg group
Floratos, E. G.; Leontaris, G. K.
2016-04-01
Non-abelian discrete symmetries are of particular importance in model building. They are mainly invoked to explain the various fermion mass hierarchies and forbid dangerous superpotential terms. In string models they are usually associated to the geometry of the compactification manifold and more particularly to the magnetised branes in toroidal compactifications. Motivated by these facts, in this note we propose a unified framework to construct representations of finite discrete family groups based on the automorphisms of the discrete and finite Heisenberg group. We focus in particular, on the PSL2 (p) groups which contain the phenomenologically interesting cases.
SU(3) flavour symmetry breaking and charmed states
Energy Technology Data Exchange (ETDEWEB)
Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Najjar, J. [Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Hyogo (Japan); Perlt, H.; Schiller, A. [Leipzig Univ. (Germany). Inst. fuer Theoretische Physik; Pleiter, D. [Forschungszentrum Juelich GmbH (Germany). Juelich Supercomputing Centre (JSC); Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Div.; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Stueben, H. [Hamburg Univ. (Germany). Regionales Rechenzentrum; Zanotti, J.M. [Adelaide Univ. (Australia). CSSM, School of Chemistry and Physics; Collaboration: QCDSF-UKQCD Collaborations
2013-11-15
By extending the SU(3) flavour symmetry breaking expansion from up, down and strange sea quark masses to partially quenched valence quark masses we propose a method to determine charmed quark hadron masses including possible QCD isospin breaking effects. Initial results for some open charmed pseudoscalar meson states and singly and doubly charmed baryon states are encouraging and demonstrate the potential of the procedure. Essential for the method is the determination of the scale using singlet quantities, and to this end we also give here a preliminary estimation of the recently introduced Wilson flow scales.
The effects of flavour symmetry breaking on hadron matrix elements
Energy Technology Data Exchange (ETDEWEB)
Cooke, A.N.; Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Kobe (Japan); Pleiter, D. [Juelich Research Centre (Germany); Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Division; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Zanotti, J.M. [Adelaide Univ. (Australia). School of Chemistry and Physics
2012-12-15
By considering a flavour expansion about the SU(3)-flavour symmetric point, we investigate how flavour-blindness constrains octet baryon matrix elements after SU(3) is broken by the mass difference between the strange and light quarks. We find the expansions to be highly constrained along a mass trajectory where the singlet quark mass is held constant, which proves beneficial for extrapolations of 2+1 flavour lattice data to the physical point. We investigate these effects numerically via a lattice calculation of the flavour-conserving and flavour-changing matrix elements of the vector and axial operators between octet baryon states.
The effects of flavour symmetry breaking on hadron matrix elements
Cooke, A N; Nakamura, Y; Pleiter, D; Rakow, P E L; Schierholz, G; Zanotti, J M
2012-01-01
By considering a flavour expansion about the SU(3)-flavour symmetric point, we investigate how flavour-blindness constrains octet baryon matrix elements after SU(3) is broken by the mass difference between the strange and light quarks. We find the expansions to be highly constrained along a mass trajectory where the singlet quark mass is held constant, which proves beneficial for extrapolations of 2+1 flavour lattice data to the physical point. We investigate these effects numerically via a lattice calculation of the flavour-conserving and flavour-changing matrix elements of the vector and axial operators between octet baryon states.
Improved staggered quark actions with reduced flavour symmetry violations for lattice QCD
Lagaë, J F
1999-01-01
We introduce a new class of actions for staggered quarks in lattice QCD which significantly reduce flavour symmetry violations in the pion mass spectrum. An action introduced by the MILC collaboration for the same purpose is seen to be a special case. We discus how such actions arise from a systematic attempt to reduce flavour symmetry violations in the weak coupling limit. It is shown that for quenched lattice QCD at 6/g^2=5.7, representative actions of this class give a considerable reduction in flavour symmetry violation over the standard staggered action, and a significant reduction over what is achieved by the MILC action.
Solving the SUSY flavour and CP problems with non-Abelian family symmetry and supergravity
Energy Technology Data Exchange (ETDEWEB)
Antusch, Stefan [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, D-80805 Muenchen (Germany)], E-mail: antusch@mppmu.mpg.de; King, Stephen F. [School of Physics and Astronomy, University of Southampton, SO16 1BJ Southampton (United Kingdom)], E-mail: sfk@hep.phys.soton.ac.uk; Malinsky, Michal [School of Physics and Astronomy, University of Southampton, SO16 1BJ Southampton (United Kingdom)], E-mail: malinsky@phys.soton.ac.uk; Ross, Graham G. [The Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford, OX13NP (United Kingdom)], E-mail: g.ross1@physics.ox.ac.uk
2009-01-05
Can a theory of flavour capable of describing the spectrum of fermion (including neutrino) masses and mixings also contain within it the seeds for a solution of the SUSY flavour and CP problems? We argue that supergravity together with a non-Abelian family symmetry can completely resolve the SUSY flavour and CP problems in a broad class of theories in which family symmetry and CP is spontaneously broken in the flavon sector. We show that a simple superpotential structure can suppress the F-terms of the flavons and GUT scale Higgs fields and that, if this mechanism is implemented, the resulting flavour and CP violation is suppressed and comfortably within the experimental limits. For illustration, we study a specific model based on SU(3) family symmetry, but similar models based on non-Abelian (continuous or discrete) family symmetry will lead to similar results.
Gauge-Higgs unification with broken flavour symmetry
Energy Technology Data Exchange (ETDEWEB)
Olschewsky, M.
2007-05-15
We study a five-dimensional Gauge-Higgs unification model on the orbifold S{sup 1}/Z{sub 2} based on the extended standard model (SM) gauge group SU(2){sub L} x U(1){sub Y} x SO(3){sub F}. The group SO(3){sub F} is treated as a chiral gauged flavour symmetry. Electroweak-, flavour- and Higgs interactions are unified in one single gauge group SU(7). The unified gauge group SU(7) is broken down to SU(2){sub L} x U(1){sub Y} x SO(3){sub F} by orbifolding and imposing Dirichlet and Neumann boundary conditions. The compactification scale of the theory is O(1) TeV. Furthermore, the orbifold S{sup 1}/Z{sub 2} is put on a lattice. This setting gives a well-defined staring point for renormalisation group (RG) transformations. As a result of the RG-flow, the bulk is integrated out and the extra dimension will consist of only two points: the orbifold fixed points. The model obtained this way is called an effective bilayered transverse lattice model. Parallel transporters (PT) in the extra dimension become nonunitary as a result of the blockspin transformations. In addition, a Higgs potential V({phi}) emerges naturally. The PTs can be written as a product e{sup A{sub y}}e{sup {eta}}e{sup A{sub y}} of unitary factors e{sup A{sub y}} and a selfadjoint factor e{sup {eta}}. The reduction 48 {yields} 35 + 6 + anti 6 + 1 of the adjoint representation of SU(7) with respect to SU(6) contains SU(2){sub L} x U(1){sub Y} x SO(3){sub F} leads to three SU(2){sub L} Higgs doublets: one for the first, one for the second and one for the third generation. Their zero modes serve as a substitute for the SM Higgs. When the extended SM gauge group SU(2){sub L} x U(1){sub Y} x SO(3){sub F} is spontaneously broken down to U(1){sub em}, an exponential gauge boson mass splitting occurs naturally. At a first step SU(2){sub L} x U(1){sub Y} x SO(3){sub F} is broken to SU(2){sub L} x U(1){sub Y} by VEVs for the selfadjoint factor e{sup {eta}}. This breaking leads to masses of flavour changing SO(3){sub F
Gauge-Higgs unification with broken flavour symmetry
International Nuclear Information System (INIS)
We study a five-dimensional Gauge-Higgs unification model on the orbifold S1/Z2 based on the extended standard model (SM) gauge group SU(2)L x U(1)Y x SO(3)F. The group SO(3)F is treated as a chiral gauged flavour symmetry. Electroweak-, flavour- and Higgs interactions are unified in one single gauge group SU(7). The unified gauge group SU(7) is broken down to SU(2)L x U(1)Y x SO(3)F by orbifolding and imposing Dirichlet and Neumann boundary conditions. The compactification scale of the theory is O(1) TeV. Furthermore, the orbifold S1/Z2 is put on a lattice. This setting gives a well-defined staring point for renormalisation group (RG) transformations. As a result of the RG-flow, the bulk is integrated out and the extra dimension will consist of only two points: the orbifold fixed points. The model obtained this way is called an effective bilayered transverse lattice model. Parallel transporters (PT) in the extra dimension become nonunitary as a result of the blockspin transformations. In addition, a Higgs potential V(Φ) emerges naturally. The PTs can be written as a product eAyeηeAy of unitary factors eAy and a selfadjoint factor eη. The reduction 48 → 35 + 6 + anti 6 + 1 of the adjoint representation of SU(7) with respect to SU(6) contains SU(2)L x U(1)Y x SO(3)F leads to three SU(2)L Higgs doublets: one for the first, one for the second and one for the third generation. Their zero modes serve as a substitute for the SM Higgs. When the extended SM gauge group SU(2)L x U(1)Y x SO(3)F is spontaneously broken down to U(1)em, an exponential gauge boson mass splitting occurs naturally. At a first step SU(2)L x U(1)Y x SO(3)F is broken to SU(2)L x U(1)Y by VEVs for the selfadjoint factor eη. This breaking leads to masses of flavour changing SO(3)F gauge bosons much above the compactification scale. Such a behaviour has no counterpart within the customary approximation scheme of an ordinary orbifold theory. This way tree-level flavour-changing-neutral-currents are
The Interplay Between GUT and Flavour Symmetries in a Pati-Salam x S4 Model
de Adelhart Toorop, Reinier; Merlo, Luca
2010-01-01
Both Grand Unified symmetries and discrete flavour symmetries are appealing ways to describe apparent structures in the gauge and flavour sectors of the Standard Model. Both symmetries put constraints on the high energy behaviour of the theory. This can give rise to unexpected interplay when building models that possess both symmetries. We investigate on the possibility to combine a Pati-Salam model with the discrete flavour symmetry $S_4$ that gives rise to quark-lepton complementarity. Under appropriate assumptions at the GUT scale, the model reproduces fermion masses and mixings both in the quark and in the lepton sectors. We show that in particular the Higgs sector and the running Yukawa couplings are strongly affected by the combined constraints of the Grand Unified and family symmetries. This in turn reduces the phenomenologically viable parameter space, with high energy mass scales confined to a small region and some parameters in the neutrino sector slightly unnatural. In the allowed regions, we can r...
Tri-Bimaximal Neutrino Mixing and Discrete Flavour Symmetries
Altarelli, Guido; Merlo, Luca
2013-01-01
We review the application of non-Abelian discrete groups to Tri-Bimaximal (TB) neutrino mixing, which is supported by experiment as a possible good first approximation to the data. After summarizing the motivation and the formalism, we discuss specific models, mainly those based on A4 but also on other finite groups, and their phenomenological implications, including the extension to quarks. The recent measurements of \\theta_13 favour versions of these models where a suitable mechanism leads to corrections to \\theta_13 that can naturally be larger than those to \\theta_12 and \\theta_23. The virtues and the problems of TB mixing models are discussed, also in connection with lepton flavour violating processes, and the different approaches are compared.
A see-saw scenario of an $A_4$ flavour symmetric standard model
Dinh, Dinh Nguyen; Văn, Phi Quang; Vân, Nguyen Thi Hông
2016-01-01
A see-saw scenario for an $A_4$ flavour symmetric standard model is presented. As before, the see-saw mechanism can be realized in several models of different types depending on different ways of neutrino mass generation corresponding to the introduction of new fields with different symmetry structures. In the present paper, a general desription of all these see-saw types is made with a more detailed investigation on type-I models. As within the original see-saw mechanism, the symmetry structure of the standard model fields decides the number and the symmetry structure of the new fields. In a model considered here, the scalar sector consists of three standard-model-Higgs-like iso-doublets ($SU_L(2)$-doublets) forming an $A_4$ triplet. The latter is a superposition of three mass-eigen states, one of which could be identified with the recently discovered Higgs boson. A possible relation to the still-deliberated 750 GeV diphoton resonance at the 13 TeV LHC collisions is also discussed. In the lepton sector, the ...
$A_4$ symmetry at colliders and in the universe
Varzielas, Ivo de Medeiros; Maurer, Vinzenz
2015-01-01
Two puzzling facts of our time are the observed patterns in the fermion masses and mixings and the existence of non-baryonic dark matter, which are both often associated with extensions of the Standard Model at higher energy scales. In this paper, we consider a solution to these two problems with the flavour symmetry ${\\mathbb A}_4\\times {\\mathbb Z}_2\\times {\\mathbb Z}_2^\\prime$, in a model which has been shown before to explain large leptonic mixings with a specific texture. The model contains 3 generations of $SU(2)_L$-doublet scalar fields, arranged as an ${\\mathbb A}_4$-triplet, that spontaneously break the electroweak symmetry, and a "dark sector" of ${\\mathbb Z}_2$-odd fields, containing one Majorana neutrino and an ${\\mathbb A}_4$-triplet $SU(2)_L$-doublet scalar field, the lightest of which provides a candidate for dark matter. Concerning the ${\\mathbb Z}_2$-even scalar fields, compared to the Standard Model, we predict additional fields with masses at the electroweak scale. We therefore investigate p...
[Re]constructing Finite Flavour Groups: Horizontal Symmetry Scans from the Bottom-Up
Talbert, Jim
2014-01-01
We present a novel procedure for identifying discrete, leptonic flavour symmetries, given a class of unitary mixing matrices. By creating explicit 3D representations for generators of residual symmetries in both the charged lepton and neutrino sector, we reconstruct large(r) non-abelian flavour groups using the GAP language for computational finite algebra. We use experimental data to construct only those generators that yield acceptable (or preferable) mixing patterns. Such an approach is advantageous because it 1) can reproduce known groups from other 'top-down' scans while elucidating their origins from residuals, 2) find new previously unconsidered groups, and 3) serve as a powerful model building tool for theorists wishing to explore exotic flavour scenarios. We test our procedure on a generalization of the canonical tri-bimaximal (TBM) form.
Flavour symmetry breaking and tuning the strange quark mass for 2+1 quark flavours
Energy Technology Data Exchange (ETDEWEB)
Bietenholz, W. [Universidad Autonoma de Mexico (Mexico). Inst. de Ciencias Nucleares; Bornyakov, V. [Institute for High Energy Physics, Protovino (Russian Federation); Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Goeckeler, M. [Regensburg Univ. (DE). Inst. fuer Theoretische Physik] (and others)
2010-12-15
QCD lattice simulations with 2+1 flavours typically start at rather large up-down and strange quark masses and extrapolate first the strange quark mass to its physical value and then the updown quark mass. An alternative method of tuning the quark masses is discussed here in which the singlet quark mass is kept fixed, which ensures that the kaon always has mass less than the physical kaon mass. Using group theory the possible quark mass polynomials for a Taylor expansion about the flavour symmetric line are found, which enables highly constrained fits to be used in the extrapolation of hadrons to the physical pion mass. Numerical results confirm the usefulness of this expansion and an extrapolation to the physical pion mass gives hadron mass values to within a few percent of their experimental values. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Weiler, A.
2007-01-16
We study flavor-changing decays of hadrons and leptons and an extra-dimensional approach to electroweak symmetry breaking. Specifically we study the framework of Minimal Flavour Violation (MFV) as an explanation of the flavour problem. We discuss the impact of a specific extra-dimensional model of the MFV class on flavour changing neutral currents. We derive model-independent upper bounds on rare decays. -We discuss the extension of the MFV framework from the quark to the lepton sector and show how baryogenesis through leptogenesis can be achieved and examine if possible correlations with charged lepton flavour violation exist. We discuss the dynamical breaking of the electroweak symmetry in extra dimensions by unifying gauge and Higgs fields and we show that realistic models are possible once the extra dimension is strongly curved. (orig.)
An SU(5) grand unified model with discrete flavour symmetries
Hernández, A E Cárcamo; Schmidt, Iván
2014-01-01
We propose a model based on the $SU(5)$ grand unification with an extra $Z_{2}\\otimes Z_{2}^{\\prime}\\otimes Z_{2}^{\\prime \\prime}\\otimes Z_{4}\\otimes Z_{12}$ flavor symmetry, which successfully describes the observed SM fermion mass and mixing pattern. The observed quark mass and mixing pattern is caused by the $Z_{4}$ and $Z_{12}$ symmetries, which are broken at very high scale by the $SU(5)$ scalar singlets $\\sigma $ and $\\chi $, charged respectively under these symmetries and which acquire VEVs at the GUT scale. The light neutrino masses are generated via a type I seesaw mechanism with three heavy Majorana neutrinos. The model has in total 17 effective free parameters, from which 2 are fixed and 15 are fitted to reproduce the experimental values of the 18 physical parameters in the quark and lepton sectors. The model predictions for both quark and lepton sectors are in excellent agreement with the experimental data.
King, Stephen F
2014-01-01
Generalised CP transformations are the only known framework which allows to predict Majorana phases in a flavour model purely from symmetry. For the first time generalised CP transformations are investigated for an infinite series of finite groups, $\\Delta(6n^2)=(Z_n\\times Z_n)\\rtimes S_3$. In direct models the mixing angles and Dirac CP phase are solely predicted from symmetry. $\\Delta(6n^2)$ flavour symmetry provides many examples of viable predictions for mixing angles. For all groups the mixing matrix has a trimaximal middle column and the Dirac CP phase is 0 or $\\pi$. The Majorana phases are predicted from residual flavour and CP symmetries where $\\alpha_{21}$ can take several discrete values for each $n$ and the Majorana phase $\\alpha_{31}$ is a multiple of $\\pi$. We discuss constraints on the groups and CP transformations from measurements of the neutrino mixing angles and from neutrinoless double-beta decay and find that predictions for mixing angles and all phases are accessible to experiments in the...
Lepton mixing predictions including Majorana phases from Δ(6n2 flavour symmetry and generalised CP
Directory of Open Access Journals (Sweden)
Stephen F. King
2014-09-01
Full Text Available Generalised CP transformations are the only known framework which allows to predict Majorana phases in a flavour model purely from symmetry. For the first time generalised CP transformations are investigated for an infinite series of finite groups, Δ(6n2=(Zn×Zn⋊S3. In direct models the mixing angles and Dirac CP phase are solely predicted from symmetry. The Δ(6n2 flavour symmetry provides many examples of viable predictions for mixing angles. For all groups the mixing matrix has a trimaximal middle column and the Dirac CP phase is 0 or π. The Majorana phases are predicted from residual flavour and CP symmetries where α21 can take several discrete values for each n and the Majorana phase α31 is a multiple of π. We discuss constraints on the groups and CP transformations from measurements of the neutrino mixing angles and from neutrinoless double-beta decay and find that predictions for mixing angles and all phases are accessible to experiments in the near future.
Quark and lepton mass matrices with A4 family symmetry
International Nuclear Information System (INIS)
Realistic quark masses and mixing angles are obtained applying the successful A4 family symmetry for leptons, motivated by the quark-lepton assignments of SU(5). The A4 symmetry is suitable to give tri-bimaximal neutrino mixing matrix which is consistent with current experimental data. We study new scenario for the quark sector with the A4 symmetry. (author)
The S{sub 3} flavour symmetry: Neutrino masses and mixings
Energy Technology Data Exchange (ETDEWEB)
Gonzalez Canales, F. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico (Mexico); Facultad de Ciencias de la Electronica, Benemerita Universidad Autonoma de Puebla (Mexico); Mondragon, A.; Mondragon, M. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico (Mexico)
2013-04-02
In this work, we discuss the neutrino masses and mixings as the realization of an S{sub 3} flavour permutational symmetry in two models, namely the Standard Model and an extension of the Standard Model with three Higgs doublets. In the S{sub 3} Standard Model, mass matrices of the same generic form are obtained for the neutrino and charged leptons when the S{sub 3} flavour symmetry is broken sequentially according to the chain S{sub 3L} x S{sub 3R} contains S{sub 3}{sup diag} contains S{sub 2}. In the minimal S{sub 3}-symmetric extension of the Standard Model, the S{sub 3} symmetry is left unbroken, and the concept of flavour is extended to the Higgs sector by introducing in the theory three Higgs fields which are SU(2) doublets. In both models, the mass matrices of the neutrinos and charged leptons are reparametrized in terms of their eigenvalues, and exact, explicit analytical expressions for the neutrino mixing angles as functions of the masses of neutrinos and charged leptons are obtained. In the case of the S{sub 3} Standard Model, from a {chi}{sup 2} fit of the theoretical expressions of the lepton mixing matrix to the values extracted from experiment, the numerical values of the neutrino mixing angles are obtained in excellent agreement with experimental data. In the S{sub 3} extension of the Standard Model, if two of the right handed neutrinos masses are degenerate, the reactor and atmospheric mixing angles are determined by the masses of the charged leptons, yielding {theta}{sub 23} in excellent agreement with experimental data, and {theta}{sub 13} different from zero but very small. If the masses of the three right handed neutrinos are assumed to be different, then it is possible to get {theta}{sub 13}also in very good agreement with experimental data. We also show the branching ratios of some selected flavour changing neutral currents (FCNC) process as well as the contribution of the exchange of a neutral flavour changing scalar to the anomaly of the
Analysis on B→VV with the Flavour SU (3) Symmetry
Institute of Scientific and Technical Information of China (English)
LIU Shao-Min; JIN Hong-Ying; LI Xue-Qian
2008-01-01
It is noted that the rescattering and annihilation effects are significant in the penguin-dominant B→VV decays. In this work, we suggest to use a unique operator at the quark level to describe all the rescattering and the penguin-induced annihilation effects in B→φK*, and the coefficient of the operator depends on the polarizations of the produced mesons. By the flavour SU(3) symmetry, we apply the same scenario to all the penguin-dominant B→VV modes.
Precision measurements of {\\theta}12 for testing models of discrete leptonic flavour symmetries
Ballett, Peter; Luhn, Christoph; Pascoli, Silvia; Schmidt, Michael A
2014-01-01
Models of leptonic flavour with discrete symmetries can provide an attractive explanation of the pattern of elements found in the leptonic mixing matrix. The next generation of neutrino oscillation experiments will allow the mixing parameters to be tested to a new level of precision, crucially measuring the CP violating phase {\\delta} for the first time. In this contribution, we present results of a systematic survey of the predictions of a class of models based on residual discrete symmetries and the prospects for excluding such models at medium- and long-term oscillation experiments. We place particular emphasis on the complementary role that a future circa 50 km reactor experiment, e.g. JUNO, can play in constraining these models.
Mass textures and wolfenstein parameters from breaking the flavour permutational symmetry
Energy Technology Data Exchange (ETDEWEB)
Mondragon, A; Rivera, T. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico,Mexico D.F. (Mexico); Rodriguez Jauregui, E. [Deutsches Elekronen-Synchrotron, Theory Group, Hamburg (Germany)
2001-12-01
We will give an overview of recent progress in the phenomenological study of quark mass matrices, quark flavour mixings and CP-violation with emphasis on the possibility of an underlying discrete, flavour permutational symmetry and its breaking, from which realistic models of mass generation could be built. The quark mixing angles and CP-violating phase, as well as the Wolfenstein parameters are given in terms of four quark mass ratios and only two parameters (Z{sup 1}/2, {phi}) characterizing the symmetry breaking pattern. Excellent agreement with all current experimental data is found. [Spanish] Daremos una visita panoramica del progreso reciente en el estudio fenomenologico de las matrices de masas y de mezclas del sabor de los quarks y la violacion de PC, con enfasis en la posibilidad de que, subyacentes al problema, se halle una simetria discreta, permutacional del sabor y su rompimiento a partir de las cuales se puedan construir modelos realistas de la generacion de las masas. Los angulos de mezcla de los quarks y la fase que viola CP, asi como los parametros de Wolfenstein se dan en terminos de cuatro razones de masas de los quarks y solamente dos parametros (Z{sup 1}/2, {phi}) que caracterizan el patron del rompimiento de la simetria. Los resultados se encuentran en excelente acuerdo con todos los datos experimentales mas recientes.
The 2-3 symmetry: Flavour Changing $b$, $\\tau$ Decays and Neutrino Mixing
Datta, A; Datta, Alakabha; Donnell, Patrick J. O'
2005-01-01
The observed pattern of neutrino mixing may be the result of a 2-3($ \\mu- \\tau$) symmetry in the leptonic sector. We consider a two higgs doublet model with a 2-3 symmetry in the down type quark and the charged lepton sector. The breaking of the 2-3 symmetry by the strange quark mass and the muon mass leads to FCNC in the quark sector and the charged lepton sector that are suppressed by ${m_s \\over m_b}$ and ${m_{\\mu} \\over m_{\\tau}}$ in addition to the mass of the heavy higgs boson of the second higgs doublet. A higgs boson mass of $ m_H \\sim 900$ GeV can explain the deviation from standard model reported in several rare B decays. Predictions for other B decays are made and new CP phase is predicted in $B_{s}-{\\bar{B}_{s}}$ mixing. The lepton flavour violating decays $ \\tau \\to \\mu \\bar{l(q)} l(q)$ are below the experimental limits. The breaking of 2-3 symmetry in the lepton sector can lead to deviations of the atmospheric neutrino mixing angle from the maximal value by $ \\sim 2$ degrees.
Energy Technology Data Exchange (ETDEWEB)
Bietenholz, W. [Univ. Autonoma de Mexico, Mexico City (Mexico). Inst. de Ciencias Nucleares; Bornyakov, V. [Inst. for High Energy Physics, Protovino (Russian Federation); Inst. for Theoretical and Experimental Physics, Moscow (Russian Federation); Goeckeler, M. [Regensburg Univ. (DE). Inst. fuer Theoretische Physik] (and others)
2011-02-15
QCD lattice simulations with 2+1 flavours typically start at rather large up-down and strange quark masses and extrapolate first the strange quark mass to its physical value and then the up-down quark mass. An alternative method of tuning the quark masses is discussed here in which the singlet quark mass is kept fixed, which ensures that the kaon always has mass less than the physical kaon mass. Using group theory the possible quark mass polynomials for a Taylor expansion about the flavour symmetric line are found, first for the general 1+1+1 flavour case and then for the 2+1 flavour case (when two quark flavours are mass degenerate). These enable highly constrained fits to be used in the extrapolation of hadrons to the physical pion mass. Numerical results for the 2+1 flavour case confirm the usefulness of this expansion and an extrapolation to the physical pion mass gives hadron mass values to within a few percent of their experimental values. Singlet quantities remain constant which allows the lattice spacing to be determined from hadron masses (without necessarily being at the physical point). Furthermore an extension of this programme to include partially quenched results is also given. (orig.)
Emmanuel-Costa, D
2011-01-01
A flavour symmetry based on Z_4 is developed in the context of SU(5) Grand Unification with the standard fermionic content plus three right-handed neutrinos. It is demanded for Z_4 to forbid some Yukawa couplings of up- and down-quarks to Higgs scalars so that the quark mass matrices M_u, M_d have Nearest-Neighbour-Interaction (NNI) structure, once they are generated through the electroweak symmetry breaking. The implementation of Z_4 requires the introduction of at least two Higgs quintets, which leads to a two Higgs doublet model at low energy scale. Due to the SU(5) unification, it is shown that the charged lepton mass matrix has also NNI form. However, the effective neutrino mass matrix exhibits a non parallel pattern, because of the type-I seesaw mechanism. Analysing all possible texture zeroes allowed by gauge-horizontal symmetry SU(5)xZ_4, it is seen that only two patterns are in agreement with the leptonic experimental data and they could be further distinguished by the light neutrino mass spectrum hi...
On spontaneous breaking of conformal symmetry by probe flavour D-branes
International Nuclear Information System (INIS)
We explore the possibilities of breaking conformal symmetry spontaneously by introducing flavour branes into conformal holographic backgrounds in the probe limit. A prototype model of such a mechanism is based on placing D7-D-bar7 configuration in the Klebanov-Witten conifold based model. In this paper we generalize this model. We conjecture on the required topology of the backgrounds and the corresponding probe brane embeddings. We identify several models that obey these requirements and admit spontaneous breaking of conformal invariance. These include type IIB conifold based examples, dual to defect field theories based on the conifold, and type IIA constructions based on the ABJM model. We identify the dilaton, the corresponding Goldstone boson, discuss its effective action and address the 'a-term'. We briefly discuss the relevance of these models to the pseudo dilaton
Energy Technology Data Exchange (ETDEWEB)
King, Stephen F., E-mail: king@soton.ac.uk; Neder, Thomas, E-mail: T.Neder@soton.ac.uk
2014-09-07
Generalised CP transformations are the only known framework which allows to predict Majorana phases in a flavour model purely from symmetry. For the first time generalised CP transformations are investigated for an infinite series of finite groups, Δ(6n{sup 2})=(Z{sub n}×Z{sub n})⋊S{sub 3}. In direct models the mixing angles and Dirac CP phase are solely predicted from symmetry. The Δ(6n{sup 2}) flavour symmetry provides many examples of viable predictions for mixing angles. For all groups the mixing matrix has a trimaximal middle column and the Dirac CP phase is 0 or π. The Majorana phases are predicted from residual flavour and CP symmetries where α{sub 21} can take several discrete values for each n and the Majorana phase α{sub 31} is a multiple of π. We discuss constraints on the groups and CP transformations from measurements of the neutrino mixing angles and from neutrinoless double-beta decay and find that predictions for mixing angles and all phases are accessible to experiments in the near future.
Phenomenology of Dark Matter from A4 Flavor Symmetry
Boucenna, M S; Morisi, S; Peinado, E; Taoso, M; Valle, J W F
2011-01-01
We investigate a model in which Dark Matter is stabilized by means of a Z2 parity that results from the same non-abelian discrete avor symmetry which accounts for the observed pattern of neutrino mixing. In our A4 example the standard model is extended by three extra Higgs doublets and the Z2 parity emerges as a remnant of the spontaneous breaking of A4 after electroweak symmetry breaking. We perform an analysis of the parameter space of the model consistent with electroweak precision tests, collider searches and perturbativity. We determine the regions compatible with the observed relic dark matter density and we present prospects for detection in direct as well as indirect Dark Matter search experiments.
Charge symmetry breaking in the A=4 hypernuclei
Gazda, Daniel
2016-01-01
Charge symmetry breaking (CSB) in the $\\Lambda$-nucleon strong interaction generates a charge dependence of $\\Lambda$ separation energies in mirror hypernuclei, which in the case of the $A=4$ mirror hypernuclei $0^+$ ground states is sizable, $\\Delta B^{J=0}_{\\Lambda}\\equiv B^{J=0}_{\\Lambda} (_{\\Lambda}^4{\\rm He})-B^{J=0}_{\\Lambda}(_{\\Lambda}^4{\\rm H})=230\\pm 90$~keV, and of opposite sign to that induced by the Coulomb repulsion in light hypernuclei. Recent {\\it ab initio} calculations of the (\\lamb{4}{H}, \\lamb{4}{He}) mirror hypernuclei $0^+_{\\rm g.s.}$ and $1^+_{\\rm exc}$ levels have demonstrated that a $\\Lambda - \\Sigma^0$ mixing CSB model due to Dalitz and von Hippel (1964) is capable of reproducing this large value of $\\Delta B^{J=0}_{\\Lambda}$. These calculations are discussed here with emphasis placed on the leading-order $\\chi$EFT hyperon-nucleon strong-interaction Bonn-J\\"{u}lich model used and the no-core shell-model calculational scheme applied. The role of one-pion exchange in producing sizable C...
Flavour, Electroweak Symmetry Breaking and Dark Matter: state of the art and future prospects
Ricciardi, Giulia; Bertuzzo, Enrico; Carmona, Adrian; Dermisek, Radovan; Huber, Tobias; Hurth, Tobias; Grossman, Yuval; Kersten, Joern; Lunghi, Enrico; Mahmoudi, Farvah; Masiero, Antonio; Neubert, Matthias; Shepherd, William; Velasco-Sevilla, Liliana
2015-01-01
With the discovery of the Higgs boson the Standard Model has become a complete and comprehensive theory, which has been verified with unparalleled precision and in principle might be valid at all scales. However, several reasons remain why we firmly believe that there should be physics beyond the Standard Model. Experiments such as the LHC, new $B$ factories, and earth- and space-based astro-particle experiments provide us with unique opportunities to discover a coherent framework for many of the long-standing puzzles of our field. Here we explore several significant interconnections between the physics of the Higgs boson, the physics of flavour, and the experimental clues we have about dark matter.
Flavour, electroweak symmetry breaking and dark matter: state of the art and future prospects
Ricciardi, Giulia; Arbey, Alexandre; Bertuzzo, Enrico; Carmona, Adrián; Dermíšek, Radovan; Huber, Tobias; Hurth, Tobias; Grossman, Yuval; Kersten, Jörn; Lunghi, Enrico; Mahmoudi, Farvah; Masiero, Antonio; Neubert, Matthias; Shepherd, William; Velasco-Sevilla, Liliana
2015-10-01
With the discovery of the Higgs boson the Standard Model has become a complete and comprehensive theory, which has been verified with unparalleled precision and in principle might be valid at all scales. However, several reasons remain why we firmly believe that there should be physics beyond the Standard Model. Experiments such as the LHC, new B factories, and earth- and space-based astro-particle experiments provide us with unique opportunities to discover a coherent framework for many of the long-standing puzzles of our field. Here we explore several significant interconnections between the physics of the Higgs boson, the physics of flavour, and the experimental clues we have about dark matter.
Pascoli, Silvia
2016-01-01
In leptonic flavour models with discrete flavour symmetries, couplings between flavons and leptons can result in special flavour structures after they gain vacuum expectation values. At the same time, they can also contribute to the other lepton-flavour-violating processes. We study the flavon-induced LFV 3-body charged lepton decays and radiative decays and we take as example the $A_4$ discrete symmetry. In $A_4$ models, a $Z_3$ residual symmetry roughly holds in the charged lepton sector for the realisation of tri-bimaximal mixing at leading order. The only processes allowed by this symmetry are $\\tau^-\\to \\mu^+ e^- e^-, e^+ \\mu^- \\mu^-$, and the other 3-body and all radiative decays are suppressed by small $Z_3$-breaking effects. These processes also depend on the representation the flavon is in, whether pseudo-real (case i) or complex (case ii). We calculate the decay rates for all processes for each case and derive their strong connection with lepton flavour mixing. In case i, sum rules for the branching...
Non-minimally flavour violating dark matter
Blanke, Monika
2015-01-01
Flavour symmetries provide an appealing mechanism to stabilize the dark matter particle. I present a simple model of quark flavoured dark matter that goes beyond the framework of minimal flavour violation. I discuss the phenomenological implications for direct and indirect dark matter detection experiments, high energy collider searches as well as flavour violating precision data.
Discrete Flavour Groups, \\theta_13 and Lepton Flavour Violation
Altarelli, Guido; Merlo, Luca; Stamou, Emmanuel
2012-01-01
Discrete flavour groups have been studied in connection with special patterns of neutrino mixing suggested by the data, such as Tri-Bimaximal mixing (groups A4, S4...) or Bi-Maximal mixing (group S4...) etc. We review the predictions for sin(\\theta_13) in a number of these models and confront them with the experimental measurements. We compare the performances of the different classes of models in this respect. We then consider, in a supersymmetric framework, the important implications of these flavour symmetries on lepton flavour violating processes, like \\mu -> e gamma and similar processes. We discuss how the existing limits constrain these models, once their parameters are adjusted so as to optimize the agreement with the measured values of the mixing angles. In the simplified CMSSM context, adopted here just for indicative purposes, the small tan(beta) range and heavy SUSY mass scales are favoured by lepton flavour violating processes, which makes it even more difficult to reproduce the reported muon g-2...
$A_4$ and CP symmetry and a model with maximal CP violation
Li, Cai-Chang; Ding, Gui-Jun
2016-01-01
We study a second CP symmetry compatible with the $A_4$ flavor group, which interchanges the representations $\\mathbf{1}'$ and $\\mathbf{1}"$. We analyze the lepton mixing patterns arising from the $A_4$ and CP symmetry broken to residual subgroups $Z_3$ and $Z_2\\times CP$ in the charged lepton and neutrino sectors respectively. One phenomenologically viable mixing pattern is found, and it predicts maximal atmospheric mixing angle as well as maximal Dirac CP phase, trivial Majorana phase and the correlation $\\sin^2\\theta_{12}\\cos^2\\theta_{13}=1/3$. We construct a concrete model based on the $A_4$ and CP symmetry, the above interesting mixing pattern is achieved, the observed charged lepton mass hierarchy is reproduced, and the reactor mixing angle $\\theta_{13}$ is of the correct order.
Phenomenological aspects of flavoured dark matter
Blanke, Monika
2015-01-01
Flavour symmetries in the dark sector are a theoretically motivated and phenomenologically appealing concept. The dark matter particle can be stabilised with the help of flavour symmetries, without the need to introduce an additional discrete symmetry by hand. Apart from the usual searches in direct and indirect detection experiments and high energy colliders, flavoured dark matter generally also gives rise to new flavour violating interactions leading to interesting signatures in rare meson decays. This proceedings article reviews a simplified model of flavoured dark matter in which the dark matter coupling to quarks constitutes a new source of flavour violation, so that the model goes beyond Minimal Flavour Violation. Particular emphasis is put on the discussion of its phenomenological implications in flavour, collider and direct detection experiments.
Boika, T; Polyakov, M V
2014-01-01
We study the implications of the flavour SU(3) symmetry for various interpretations of the neutron anomaly in the $\\gamma N\\to\\eta N$ cross section. We show that the explanation of the neutron anomaly due to interference of known N(1535) and N(1650) resonances implies that N(1650) resonance should have a huge coupling to $\\phi$-meson -- at least 5 times larger than the corresponding $\\rho^0$ coupling. In terms of quark degrees of freedom this means that the well-known N(1650) resonance must be a "cryptoexotic pentaquark"-- its wave function should contain predominantly an $s\\bar s$ component. It turns out that the "conventional" interpretation of the neutron anomaly by the interference of known resonances metamorphoses into unconventional physics picture of N(1650).
Neutrino Masses from an A4 Symmetry in Holographic Composite Higgs Models
del Aguila, Francisco; Santiago, Jose
2010-01-01
We show that holographic composite Higgs Models with a discrete A4 symmetry naturally predict hierarchical charged lepton masses and an approximate tri-bimaximal lepton mixing with the correct scale of neutrino masses. They also satisfy current constraints from electroweak precision tests, lepton flavor violation and lepton mixing in a large region of parameter space. Two phenomenologically relevant features arise in these models. First, an extra suppression on the lepton Yukawa couplings makes the tau lepton more composite than naively expected from its mass. As a consequence new light leptonic resonances, with masses as low as few hundreds of GeV, large couplings to tau and a very characteristic collider phenomenology, are quite likely. Second, the discrete symmetry A4 together with the model structure provide a double-layer of flavor protection that allows to keep tree-level mediated processes below present experimental limits. One-loop processes violating lepton flavor, like mu -> e gamma, may be however ...
Flavoured Dark Matter Beyond MFV
Blanke, Monika
2014-01-01
We review a model of quark flavoured dark matter with new flavour violating interactions. This simplified model describes Dirac fermionic dark matter that is charged under a new U(3) flavour symmetry and couples to right-handed down quarks via a scalar mediator. The corresponding coupling matrix is assumed to be the only new source of flavour violation, which we refer to as the Dark Minimal Flavour Violation (DMFV) hypothesis. This ansatz ensures the stability of dark matter. We discuss the phenomenology of the simplest DMFV model in flavour violating observables, LHC searches, and direct dark matter detection experiments. Especially interesting is the non-trivial interplay between the constraints from the different sectors.
Constraining Type I Seesaw with $A_4$ Flavor Symmetry From Neutrino Data and Leptogenesis
Kalita, Rupam
2015-01-01
We study a type I seesaw model of neutrino masses within the framework of $A_4$ flavor symmetry. Incorporating the presence of both singlet and triplet flavons under $A_4$ symmetry, we construct the leptonic mass matrices involved in type I seesaw mechanism. We then construct the light neutrino mass matrix using the $3\\sigma$ values of neutrino oscillation parameters keeping the presently undetermined parameters namely, the lightest neutrino mass $m_{\\text{lightest}}$, one Dirac CP phase $\\delta$ and two Majorana phases $\\alpha, \\beta$ as free parameters. Comparing the mass matrices derived using $A_4$ parameters as well as light neutrino parameters, we then evaluate all the $A_4$ parameters in terms of light neutrino parameters. Assuming some specific vacuum alignments of $A_4$ triplet flavon field, we then numerically evaluate all the free parameters in the light neutrino sector, using which we also find out the remaining $A_4$ parameters. We then use the numerical values of these parameters to calculate ba...
Nonzero theta(13) for neutrino mixing in the context of A(4) symmetry
Ma, Ernest
2011-01-01
In the original 2004 paper which first derived tribimaximal mixing in the context of A(4), i.e. the non-Abelian finite symmetry group of the tetrahedron (Plato's fire), as its simplest application, it was also pointed out how theta(13) nonzero may be accommodated. On the strength of the new T2K result that 0.03 (0.04) < sin^2 2 theta(13) < 0.28 (0.34) for delta(CP)=0 and normal (inverted) neutrino mass hierarchy, we perform a more detailed analysis of how this original idea may be realized in the context of A(4).
New and trivial C P symmetry for extended A4 flavor
Nishi, C. C.
2016-05-01
The combination of νμ-ντ exchange together with C P conjugation in the neutrino sector (known as CPμ τ symmetry or μ τ reflection) is known to predict the viable pattern θ23=4 5 ° , a maximal Dirac C P phase, and trivial Majorana phases. We implement such a C P symmetry as a new C P symmetry in theories with A4 flavor. The implementation in a complete renormalizable model leads to a new form for the neutrino mass matrix that leads to further predictions: a normal hierarchical spectrum with a lightest mass and mβ β (0 ν 2 β ) of only few meV, and either ν1 or ν2 has opposite C P parity. An approximate Lμ-Lτ symmetry arises naturally and controls the flavor structure of the model. The light neutrino masses are generated by the extended seesaw mechanism with six right-handed neutrinos (RHNs). The requirement of negligible one-loop corrections to light neutrino masses, the validity of the extended seesaw approximation, and not too long-lived beyond-the-Standard-Model states to comply with big bang nucleosynthesis essentially restricts the parameters of the model to a small region: three relatively light right-handed neutrinos at the GeV scale, heavier neutrinos at the electroweak scale, and Yukawa couplings smaller than the electron Yukawa. Such small Yukawa couplings render these RHNs unobservable in terrestrial experiments.
Flavour violation in general supergravity
Chankowski, P H; Pokorski, Stefan; Chankowski, Piotr H.; Lebedev, Oleg; Pokorski, Stefan
2005-01-01
We reappraise the flavour changing neutral currents (FCNC) problem in string--derived supergravity models. We overview and classify possible sources of flavour violation and find that the problem often does not arise in classes of models which generate hierarchical Yukawa matrices. In such models, constraints from the K- and D-meson systems leave room for substantial flavour non-universality of the soft terms. The current B-physics experiments only begin to probe its natural range. Correlations among different observables can allow one to read off the chirality structure of flavour violating sources. We briefly discuss the lepton sector where the problem of FCNC is indeed serious and perhaps points at an additional symmetry or flavour universality.
The role of flavon cross couplings in leptonic flavour mixing
Pascoli, Silvia; Zhou, Ye-Ling
2016-06-01
In models with discrete flavour symmetries, flavons are critical to realise specific flavour structures. Leptonic flavour mixing originates from the misalignment of flavon vacuum expectation values which respect different residual symmetries in the charged lepton and neutrino sectors. Flavon cross couplings are usually forbidden, in order to protect these symmetries. Contrary to this approach, we show that cross couplings can play a key role and give raise to necessary corrections to flavour-mixing patterns, including a non-zero value for the reactor angle and CP violation. For definiteness, we present two models based on A 4. In the first model, all flavons are assumed to be real or pseudo-real, with 7 real degrees of freedom in the flavon sector in total. A sizable reactor angle associated with nearly maximal CP violation is achieved, and, as both originate from the same cross coupling, a sum rule results with a precise prediction for the value of the Dirac CP-violating phase. In the second model, the flavons are taken to be complex scalars, which can be connected with supersymmetric models and multi-Higgs models. The complexity properties of flavons provide new sources for generating the reactor angle. Models in this new approach introduce very few degrees of freedom beyond the Standard Model and can be more economical than those in the framework of extra dimension or supersymmetry.
The role of flavon cross couplings in leptonic flavour mixing
Pascoli, Silvia
2016-01-01
In models with discrete flavour symmetries, flavons are critical to realise specific flavour structures. Leptonic flavour mixing originates from the misalignment of flavon vacuum expectation values which respect different residual symmetries in the charged lepton and neutrino sectors. Flavon cross couplings are usually forbidden, in order to protect these symmetries. Contrary to this approach, we show that cross couplings can play a key role and give raise to necessary corrections to flavour-mixing patterns, including a non-zero value for the reactor angle and CP violation. For definiteness, we present two models based on $A_4$. In the first model, all flavons are assumed to be real or pseudo-real, with 7 real degrees of freedom in the flavon sector in total. A sizable reactor angle associated with nearly maximal CP violation is achieved, and, as both originate from the same cross coupling, a sum rule results with a precise prediction for the value of the Dirac CP-violating phase. In the second model, the fla...
Non-zero $\\theta_{13}$ and CP violation in a model with $A_4$ flavor symmetry
Ahn, Y H
2012-01-01
Motivated by $5.2\\sigma$ observation of non-zero $\\theta_{13}$ from the Daya Bay experiment, we propose a renormalizable neutrino model with $A_4$ discrete symmetry accounting for deviations from the tri-bimaximal (TBM) mixing pattern of neutrino mixing matrix indicated by neutrino oscillation data. In the model, the light neutrino masses can be generated by radiative corrections, and we show how the light neutrino mass matrix can be diagonalized by the PMNS mixing matrix whose entries are determined by the current neutrino data including the Daya Bay result. We show that the origin of the deviations from the TBM mixing is non-degeneracy of the neutrino Yukawa coupling constants, and unremovable CP phases in the neutrino Yukawa matrix give rise to the low energy CP violation measurable from neutrino oscillation as well as high energy CP violation required for leptogenesis.
International Nuclear Information System (INIS)
For the consumer, meat is characterized by a certain number of organoleptic qualities; among them, flavour -that is to say the association of both odour and taste- plays a leading part. This property is based upon a great number of chemical components: some volatile components are responsible for the aroma and some non-volatile ones for the taste. These substances are either made or released during the heating of the meat on account of components called precursors which are produced during the aging of the meat. The two main reactions which preside over the elaboration of flavour are: the Maillard's reaction and the autooxidation reactions. Meat flavour is associated with the animal characteristics; it is influenced by the ante- and post mortem treatments as well as by the technological treatments for storing it. The use of synthetical flavours is to be considered as possible in the future
Ciafaloni, Paolo; Torrente-Lujan, Emilio; Urbano, Alfredo
2009-01-01
We address the problem of rationalizing the pattern of fermion masses and mixings by adding a nonabelian flavor symmetry in a grand unified framework. With this purpose, we include an A4 flavor symmetry into a unified renormalizable SUSY GUT SU(5) model. With the help of the "Type II Seesaw" mechanism we are able to obtain the pattern of observed neutrino mixings in a natural way, through the so called tribimaximal matrix.
Spontaneous CP violation and neutral flavour conservation
International Nuclear Information System (INIS)
The conditions for one-loop stability of neutral flavour conservation in SU(2)LxU(1) models with spontaneous CP violation are analysed. In addition to previously known cases there is an essentially unique two-generation model with two Higgs doublets where neutral flavour conservation is guaranteed to all orders by a non-standard CP symmetry. (orig.)
Two-Higgs-doublet models with Minimal Flavour Violation
Carlucci, Maria Valentina
2010-01-01
The tree-level flavour-changing neutral currents in the two-Higgs-doublet models can be suppressed by protecting the breaking of either flavour or flavour-blind symmetries, but only the first choice, implemented by the application of the Minimal Flavour Violation hypothesis, is stable under quantum corrections. Moreover, a two-Higgs-doublet model with Minimal Flavour Violation enriched with flavour-blind phases can explain the anomalies recently found in the Delta F = 2 transitions, namely the large CP-violating phase in B_s mixing and the tension between epsilon_K and S_\\psi_K.
Running Effects on Lepton Mixing Angles in Flavour Models with Type I Seesaw
Lin, Y; Paris, A
2009-01-01
We study renormalization group running effects on neutrino mixing patterns when a (type I) seesaw model is implemented by suitable flavour symmetries. We are particularly interested in mass-independent mixing patterns to which the widely studied tribimaximal mixing pattern belongs. In this class of flavour models, the running contribution from neutrino Yukawa coupling, which is generally dominant at energies above the seesaw threshold, can be absorbed by a small shift on neutrino mass eigenvalues leaving mixing angles unchanged. Consequently, in the whole running energy range, the change in mixing angles is due to the contribution coming from charged lepton sector. Subsequently, we analyze in detail these effects in an explicit flavour model for tribimaximal neutrino mixing based on an A4 discrete symmetry group. We find that for normally ordered light neutrinos, the tribimaximal prediction is essentially stable under renormalization group evolution. On the other hand, in the case of inverted hierarchy, the d...
Institute of Scientific and Technical Information of China (English)
奎斯特国际有限公司
2004-01-01
@@ A good flavour must taste realistic and natural as well as performing under tough conditions, says Mairi Coia. In conjunction with texture or mouthfeel, flavour is the most important aspect of food. It is the one thing can bring consumers back to a product again and again - or not, as the case may be. In short, taste is the number one attribute in food and that is why the global fiavour business is worth A5 billion every year as manufacturers strive to make food taste better and fresher for longer.
Ciafaloni, Paolo; Torrente-Lujan, Emilio; Urbano, Alfredo
2009-01-01
We analyze all possible extensions of the recently proposed minimal renormalizable SUSY SU(5) grand unified model with the inclusion of an additional A4 flavor symmetry. We find that there are 5 possible Cases but only one of them is phenomenologically interesting. We develop in detail such Case and we show how the fermion masses and mixing angles come out. As prediction we obtain the neutrino masses of order of 0.1 eV with an inverted hierarchy.
Deuzeman, A; Pallante, E
2008-01-01
When the flavour content of QCD is increased sufficiently, the theory develops a non-trivial infra red fixed point. Thus, for a number of flavours above a certain critical value, but not yet so high that asymptotic freedom is lost, QCD becomes a conformal field theory. The location of the lower limit of this conformal window has not yet been unequivocally determined. Using an improved lattice action, and exploiting modern algorithms allowing for larger lattices and lower quark masses, we have shown that the theory of QCD with eight flavours breaks chiral symmetry in the continuum. We present proof that the accompanying transition is thermal in nature and as a consequence, the conformal window of QCD can only start afterwards, corroborating recent analytical studies at the expense of older results.
Neutrinos Masses in a Multi-Higgs Model with A4 symmetry
Machado, A. C. B.; Montero, J. C.; Pleitez, V.
2012-08-01
Presently it is well known that neutrino oscillation data are well described by massive neutrinos and their mixing. This suggests changes in the standard model (SM) and makes the flavor physics even more interesting. Recently, it has been proposed a multi-Higgs extension of the SM with Abelian and non-Abelian discrete symmetries which seeks to explain the origin of the masses and mixing matrices in all charge sectors.
Neutrino Mass and Flavour Models
King, Stephen F
2009-01-01
We survey some of the recent promising developments in the search for the theory behind neutrino mass and tri-bimaximal mixing, and indeed all fermion masses and mixing. We focus in particular on models with discrete family symmetry and unification, and show how such models can also solve the SUSY flavour and CP problems. We also discuss the theoretical implications of the measurement of a non-zero reactor angle, as hinted at by recent experimental measurements.
Ab-initio calculations of charge symmetry breaking in the A=4 hypernuclei
Gazda, Daniel
2015-01-01
We report on ab-initio NCSM calculations of the A=4 mirror Lambda hypernuclei Lambda-4H and Lambda-4He, using the Bonn-Juelich LO chiral EFT YN potentials plus a CSB Lambda0--Sigma0 mixing vertex. In addition to reproducing rather well the 0+ (g.s.) and 1+ (exc.) binding energies, these four-body calculations demonstrate for the first time that the observed CSB splitting of mirror levels, reaching hundreds of keV for 0+ (g.s.), can be reproduced using realistic theoretical interaction models, although with a non-negligible momentum cutoff dependence. Our results are discussed in relation to recent measurements of the Lambda-4H (0+ g.s.) binding energy [MAMI A1 Collaboration, Phys. Rev. Lett. 114, 232501 (2015)] and the Lambda-4He (1+ exc.) excitation energy [J-PARC E13 Collaboration, Phys. Rev. Lett. 115, 222501 (2015)].
Deviation from tri-bimaximal mixing and flavor symmetry breaking in a seesaw type A4 model
International Nuclear Information System (INIS)
We have studied the contribution of higher order corrections of the flavor symmetry breaking in the A4 seesaw model with the supersymmetry. Taking account of possible higher dimensional mass operators, we predict the deviation from the tri-bimaximal lepton mixing for both normal hierarchy and inverted hierarchy of neutrino masses. We have found that the value of sin22θ23 is larger than 0.96 and the upper bound of sin2θ13 is 0.01. We have also examined the flavor changing neutral current of leptons from the soft SUSY breaking in slepton masses and A-terms within the framework of supergravity theory. Those magnitudes are enough suppressed to be consistent with experimental constraints.
Constraining multi-Higgs flavour models
Energy Technology Data Exchange (ETDEWEB)
Gonzalez Felipe, R.; Silva, Joao P. [Rua Conselheiro Emidio Navarro 1, Instituto Superior de Engenharia de Lisboa-ISEL, Lisbon (Portugal); Universidade de Lisboa, Centro de Fisica Teorica de Particulas (CFTP), Instituto Superior Tecnico, Lisbon (Portugal); Ivanov, I.P. [Universite de Liege, IFPA, Liege (Belgium); Sobolev Institute of Mathematics, Novosibirsk (Russian Federation); Ghent University, Department of Physics and Astronomy, Ghent (Belgium); Nishi, C.C. [Universidade Federal do ABC-UFABC, Santo Andre, SP (Brazil); Serodio, Hugo [Universitat de Valencia-CSIC, Departament de Fisica Teorica and IFIC, Burjassot (Spain)
2014-07-15
To study a flavour model with a non-minimal Higgs sector one must first define the symmetries of the fields; then identify what types of vacua exist and how they may break the symmetries; and finally determine whether the remnant symmetries are compatible with the experimental data. Here we address all these issues in the context of flavour models with any number of Higgs doublets. We stress the importance of analysing the Higgs vacuum expectation values that are pseudo-invariant under the generators of all subgroups. It is shown that the only way of obtaining a physical CKM mixing matrix and, simultaneously, non-degenerate and non-zero quark masses is requiring the vacuum expectation values of the Higgs fields to break completely the full flavour group, except possibly for some symmetry belonging to baryon number. The application of this technique to some illustrative examples, such as the flavour groups Δ(27), A{sub 4} and S{sub 3}, is also presented. (orig.)
Linear flavour violation and anomalies in B physics
Gripaios, Ben; Renner, S A
2015-01-01
We propose renormalizable models of new physics that can explain various anomalies observed in decays of B-mesons to electron and muon pairs. The new physics states couple to linear combinations of Standard Model fermions, yielding a pattern of flavour violation that gives a consistent fit to the gamut of flavour data. Accidental symmetries prevent contributions to baryon- and lepton-number-violating processes, as well as enforcing a loop suppression of new physics contributions to flavour violating processes. Data require that the new flavour-breaking couplings are largely aligned with the Yukawa couplings of the SM and so we also explore patterns of flavour symmetry breaking giving rise to this structure.
Minimal flavour violation and neutrino masses without R-parity
DEFF Research Database (Denmark)
Arcadi, G.; Di Luzio, L.; Nardecchia, M.
2012-01-01
symmetry breaking all the couplings of the superpotential including the R-parity violating ones. If R-parity violation is responsible for neutrino masses, our setup can be seen as an extension of MFV to the lepton sector. We analyze two patterns based on the non-abelian flavour symmetries SU(3)(4) circle...... times SU(4) and SU(3)(5). In the former case the total lepton number and the lepton flavour number are broken together, while in the latter the lepton number can be broken independently by an abelian spurion, so that visible effects and peculiar correlations can be envisaged in flavour changing charged...
Bazzocchi, F; Picariello, M; Torrente-Lujan, E
2008-01-01
We present a common explanation of the fermion mass hierarchy and the large lepton mixing angles in the context of a grand unified flavor and gauge theory (GUTF). Our starting point is a SU(3)xU(1) flavor symmetry and a SO(10) GUT, a basic ingredient of our theory which plays a major role is that two different breaking pattern of the flavor symmetry are at work. On one side, the dynamical breaking of SU(3)xU(1) flavor symmetry into U(2)xZ_3 explains why one family is much heavier than the others. On the other side, an explicit symmetry breaking of SU(3) into a discrete flavor symmetry leads to the observed tribimaximal mixing for the leptons. We write an explicit model where this discrete symmetry group is A4. Naturalness of the charged fermion mass hierarchy appears as a consequence of the continuous SU(3) flavor symmetry. Moreover, the same discrete A4-GUT invariant operators are the root of the large lepton mixing, small Cabibbo angle, and neutrino masses.
Lepton flavour violation in composite Higgs models
Energy Technology Data Exchange (ETDEWEB)
Feruglio, Ferruccio, E-mail: feruglio@pd.infn.it; Paradisi, Paride, E-mail: paride.paradisi@pd.infn.it [Sezione di Padova, Dipartimento di Fisica e Astronomia ‘G. Galilei’, INFN, Università di Padova, Via Marzolo 8, 35131, Padua (Italy); Pattori, Andrea, E-mail: pattori@physik.uzh.ch [Physik-Institut, Universität Zürich, 8057, Zurich (Switzerland)
2015-12-08
We discuss in detail the constraints on the partial compositeness coming from flavour and CP violation in the leptonic sector. In the first part we present a formulation of partial compositeness in terms of a flavour symmetry group and a set of spurions, whose background values specify the symmetry breaking pattern. In such a framework we construct the complete set of dimension-six operators describing lepton flavour violation and CP violation. By exploiting the existing bounds, we derive limits on the compositeness scale in different scenarios, characterised by increasing restrictions on the spurion properties. We confirm that in the most general case the compositeness scale should lie well above 10 TeV. However, if in the composite sector the mass parameters and Yukawa couplings are universal, such a bound can be significantly lowered, without necessarily reproducing the case of minimal flavour violation. The most sensitive processes are decays of charged leptons either of radiative type or into three charged leptons, μ→e conversion in nuclei and the electric dipole moment of the electron. In the second part we explicitly compute the Wilson coefficients of the relevant dimension-six operators in the so-called two-site model, embodying the symmetry breaking pattern discussed in our first part, and we compare the results with those of the general spurion analysis.
Lepton flavour violation in composite Higgs models
Energy Technology Data Exchange (ETDEWEB)
Feruglio, Ferruccio; Paradisi, Paride [Universita di Padova, Dipartimento di Fisica e Astronomia ' G. Galilei' , Padua (Italy); INFN, Padua (Italy); Pattori, Andrea [Universitaet Zuerich, Physik-Institut, Zurich (Switzerland)
2015-12-15
We discuss in detail the constraints on the partial compositeness coming from flavour and CP violation in the leptonic sector. In the first part we present a formulation of partial compositeness in terms of a flavour symmetry group and a set of spurions, whose background values specify the symmetry breaking pattern. In such a framework we construct the complete set of dimension-six operators describing lepton flavour violation and CP violation. By exploiting the existing bounds, we derive limits on the compositeness scale in different scenarios, characterised by increasing restrictions on the spurion properties. We confirm that in the most general case the compositeness scale should lie well above 10 TeV. However, if in the composite sector the mass parameters and Yukawa couplings are universal, such a bound can be significantly lowered, without necessarily reproducing the case of minimal flavour violation. The most sensitive processes are decays of charged leptons either of radiative type or into three charged leptons, μ → e conversion in nuclei and the electric dipole moment of the electron. In the second part we explicitly compute the Wilson coefficients of the relevant dimension-six operators in the so-called two-site model, embodying the symmetry breaking pattern discussed in our first part, and we compare the results with those of the general spurion analysis. (orig.) 7.
New Physics in the Flavour Sector
Crivellin, Andreas
2016-01-01
Several experiments observed deviations from the Standard Model (SM) in the flavour sector: LHCb found a $4-5\\,\\sigma$ discrepancy compared to the SM in $b\\to s\\mu^+\\mu^-$ transitions (recently supported by an Belle analysis) and CMS reported a non-zero measurement of $h\\to\\mu\\tau$ with a significance of $2.4\\,\\sigma$. Furthermore, BELLE, BABAR and LHCb founds hints for the violation of flavour universality in $B\\to D^{(*)}\\tau\
Lepton flavour violating processes in an S_3-symmetric model
Mondragón, A; Peinado, E
2008-01-01
A variety of lepton flavour violating effects related to the recent discovery of neutrino oscillations and mixings is here systematically discussed in terms of an S_3-flavour permutational symmetry. After presenting some relevant results on lepton masses and mixings, previously derived in a minimal S_3-invariant extension of the Standard Model, we compute the branching ratios of some selected flavour-changing neutral current processes (FCNC) as well as the contribution of the exchange of neutral flavour-changing scalar to the anomaly of the magnetic moment of the muon. We found that the minimal S_3-invariant extension of the Standard Model describes successfully masses and mixings, as well as, all flavour changing neutral current processes in excellent agreement with experiment.
A T' Flavour Model for Fermions and its Phenomenology
Merlo, Luca
2011-01-01
We present a supersymmetric flavour model based on the T' discrete group, which explains fermion masses and mixings. The flavour symmetry, acting in the supersymmetric sector, provides well defined sfermion mass matrices and the resulting supersymmetric spectrum accounts for sufficiently light particles that could be seen at LHC. Furthermore, several contributions to FCNC processes are present and they can be useful to test the model in the present and future experiments. We will review the main results for both leptons and quarks.
Searching for New Physics through correlations of Flavour Observables
Girrbach, Jennifer
2013-01-01
The coming flavour precision era will allow to uncover various patterns of flavour violation in different New Physics scenarios. We discuss different classes of them. A simple extension of the Standard Model that generally introduces new sources of flavour and CP violation as well as right-handed currents is the addition of a U(1) gauge symmetry to the SM gauge group. In such Z' models correlations between various flavour observables emerge that could test and distinguish different Z' scenarios. A concrete model with flavour violating Z' couplings is the 331 model based on the gauge group SU(3)_C x SU(3)_L x U(1)_X. We also study tree-level FCNCs mediated by heavy neutral scalars and/or pseudo-scalars H^0(A^0). Furthermore the implications of an additional approximate global U(2)^3 flavour symmetry is shortly discussed. Finally a model with vectorlike fermions and flavour violating Z couplings is presented. We identify a number of correlations between various observables that differ from those known from cons...
Dark matter and observable Lepton Flavour Violation
Heurtier, Lucien; Teresi, Daniele
2016-01-01
Seesaw models with leptonic symmetries allow right-handed (RH) neutrino masses at the electroweak scale, or even lower, at the same time having large Yukawa couplings with the Standard Model leptons, thus yielding observable effects at current or near-future lepton-flavour-violation (LFV) experiments. These models have been previously considered also in connection to low-scale leptogenesis, but the combination of observable LFV and successful leptogenesis has appeared to be difficult to achie...
Leptogenesis and residual CP symmetry
Chen, Peng; King, Stephen F
2016-01-01
We discuss flavour dependent leptogenesis in the framework of lepton flavour models based on discrete flavour and CP symmetries applied to the type-I seesaw model. Working in the flavour basis, we analyse the case of two general residual CP symmetries in the neutrino sector, which corresponds to all possible semi-direct models based on a preserved $Z_2$ in the neutrino sector, together with a CP symmetry, which constrains the PMNS matrix up to a single free parameter which may be fixed by the reactor angle. We systematically study and classify this case for all possible residual CP symmetries, and show that the $R$-matrix is tightly constrained up to a single free parameter, with only certain forms being consistent with successful leptogenesis, leading to possible connections between leptogenesis and PMNS parameters. The formalism is completely general in the sense that the two residual CP symmetries could result from any high energy discrete flavour theory which respects any CP symmetry. As a simple example,...
Pillot, Philippe
2008-01-01
Open heavy flavours and heavy quarkonium states are expected to provide essential informa- tion on the properties of the strongly interacting system fo rmed in the early stages of heavy-ion collisions at very high energy density. Such probes are espe cially promising at LHC energies where heavy quarks (both c and b) are copiously produced. The ALICE detector shall measure the production of open heavy flavours and heavy quarkonium st ates in both proton-proton and heavy-ion collisions at the LHC. The expected performances of ALICE for heavy flavour physics is discussed based on the results of simulation studies on a s election of benchmark channels
Grabalosa Gandara, M
2009-01-01
To do precise CP violation measurements, the most possible accurate knowledge of the flavour at production of the reconstructed B meson is required. This poster summarizes the flavour tagging performances for the LHCb experiment. We use same side an opposite side algorithms to establish wheter the meson contained a b or a b\\bar quark. The final decision is obtained through a combination of several methods. The use of control channels, decays to a flavour specific final state, will allow to determine the wrong tag fraction \\omega (the probability of a tag to be wrong), which can be used as input for the determination of CKM unitary triangle angles.
Energy Technology Data Exchange (ETDEWEB)
Albrecht, Michaela E.
2010-08-16
The minimal-flavour-violating (MFV) hypothesis considers the Standard Model (SM) Yukawa matrices as the only source of flavour violation. In this work, we promote their entries to dynamical scalar spurion fields, using an effective field theory approach, such that the maximal flavour symmetry (FS) of the SM gauge sector is formally restored at high energy scales. The non-vanishing vacuum expectation values of the spurions induce a sequence of FS breaking and generate the observed hierarchy in the SM quark masses and mixings. The fact that there exists no explanation for it in the SM is known as the flavour puzzle. Gauging the non-abelian subgroup of the spontaneously broken FS, we interpret the associated Goldstone bosons as the longitudinal degrees of freedom of the corresponding massive gauge bosons. Integrating out the heavy Higgs modes in the Yukawa spurions leads directly to flavour-changing neutral currents (FCNCs) at tree level. The coefficients of the effective four-quark operators, resulting from the exchange of heavy flavoured gauge bosons, strictly follow the MFV principle. On the other hand, the Goldstone bosons associated with the global abelian symmetry group behave as weakly coupled axions which can be used to solve the strong CP problem within a modified Peccei-Quinn formalism. Models with a warped fifth dimension contain five-dimensional (5D) fermion bulk mass matrices in addition to their 5D Yukawa matrices, which thus represent an additional source of flavour violation beyond MFV. They can address the flavour puzzle since their eigenvalues allow for a different localisation of the fermion zero mode profiles along the extra dimension which leads to a hierarchy in the effective four-dimensional (4D) Yukawa matrices. At the same time, the fermion splitting introduces non-universal fermion couplings to Kaluza-Klein (KK) gauge boson modes, inducing tree-level FCNCs. Within a Randall-Sundrum model with custodial protection (RSc model) we carefully work
Alonso, R; Gavela, M B; Grinstein, B; Merlo, L; Quilez, P
2016-01-01
The gauging of the lepton flavour group is considered in the Standard Model context and in its extension with three right-handed neutrinos. The anomaly cancellation conditions lead to a Seesaw mechanism as underlying dynamics for all leptons; requiring in addition a phenomenologically viable setup leads to Majorana masses for the neutral sector: the type I Seesaw Lagrangian in the Standard Model case and the inverse Seesaw in the extended model. Within the minimal extension of the scalar sector, the Yukawa couplings are promoted to scalar fields in the bifundamental of the flavour group. The resulting low-energy Yukawa couplings are proportional to inverse powers of the vacuum expectation values of those scalars; the protection against flavour changing neutral currents differs from that of Minimal Flavor Violation. In all cases, the $\\mu-\\tau$ flavour sector exhibits rich and promising phenomenological signals.
Supersymmetric Radiative Flavour
Conlon, Joseph P.; Pedro, Francisco G.
2011-01-01
We examine possibilities for the radiative generation of the Yukawa couplings and flavour structure in supersymmetric models in the supersymmetric phase. Not withstanding the non-renormalisation of the Wilsonian superpotential, this can occur through the 2-loop vertex renormalisation of the physical 1PI couplings. We describe this effect and construct models in which this occurs. For models attempting to reproduce the full flavour structure of the Standard Model, we analyse the tension betwee...
Leptonic Dirac CP violation predictions from residual discrete symmetries
Directory of Open Access Journals (Sweden)
I. Girardi
2016-01-01
Full Text Available Assuming that the observed pattern of 3-neutrino mixing is related to the existence of a (lepton flavour symmetry, corresponding to a non-Abelian discrete symmetry group Gf, and that Gf is broken to specific residual symmetries Ge and Gν of the charged lepton and neutrino mass terms, we derive sum rules for the cosine of the Dirac phase δ of the neutrino mixing matrix U. The residual symmetries considered are: i Ge=Z2 and Gν=Zn, n>2 or Zn×Zm, n,m≥2; ii Ge=Zn, n>2 or Zn×Zm, n,m≥2 and Gν=Z2; iii Ge=Z2 and Gν=Z2; iv Ge is fully broken and Gν=Zn, n>2 or Zn×Zm, n,m≥2; and v Ge=Zn, n>2 or Zn×Zm, n,m≥2 and Gν is fully broken. For given Ge and Gν, the sum rules for cosδ thus derived are exact, within the approach employed, and are valid, in particular, for any Gf containing Ge and Gν as subgroups. We identify the cases when the value of cosδ cannot be determined, or cannot be uniquely determined, without making additional assumptions on unconstrained parameters. In a large class of cases considered the value of cosδ can be unambiguously predicted once the flavour symmetry Gf is fixed. We present predictions for cosδ in these cases for the flavour symmetry groups Gf=S4, A4, T′ and A5, requiring that the measured values of the 3-neutrino mixing parameters sin2θ12, sin2θ13 and sin2θ23, taking into account their respective 3σ uncertainties, are successfully reproduced.
Flavour physics and CP violation
Nir, Y
2010-01-01
This is a written version of a series of lectures aimed at graduate students in particle theory/string theory/particle experiment familiar with the basics of the Standard Model. We explain the many reasons for the interest in flavour physics. We describe flavour physics and the related CP violation within the Standard Model, and explain how the B-factories proved that the Kobayashi- Maskawa mechanism dominates the CP violation that is observed in meson decays. We explain the implications of flavour physics for new physics. We emphasize the “new physics flavour puzzle”. As an explicit example, we explain how the recent measurements ofD0−D 0 mixing constrain the supersymmetric flavour structure. We explain how the ATLAS and CMS experiments can solve the new physics flavour puzzle and perhaps shed light on the standard model flavour puzzle. Finally, we describe various interpretations of the neutrino flavour data and their impact on flavour models.
Searches for Lepton Flavour Violation and Lepton Number Violation in Hadron Decays
Seyfert, P
2012-01-01
In the Standard Model of particle physics, lepton flavour and lepton number are conserved quantities although no fundamental symmetry demands their conservation. I present recent results of searches for lepton flavour and lepton number violating hadron decays measured at the B factories and LHCb. In addition, the LHCb collaboration has recently performed a search for the lepton flavour violating decay $\\tau^- \\mu^- \\mu^- \\mu^+$ The obtained upper exclusion limit, that has been presented in this talk for the first time, is of the same order of magnitude as those observed at the B factories. This is the first search for a lepton flavour violating $\\tau$ decay at a hadron collider.
Revisiting Lepton Flavour Universality in B Decays
Feruglio, Ferruccio; Pattori, Andrea
2016-01-01
Lepton flavour universality (LFU) in B-decays is revisited in a model-independent way by considering semileptonic operators defined at a scale Lambda above the electroweak scale v. The importance of quantum effects, so far neglected in the literature, is emphasised. We construct the low-energy effective Lagrangian taking into account the running effects from Lambda down to v through the one-loop renormalization group equations (RGE) in the limit of exact electroweak symmetry and QED RGEs from v down to the 1 GeV scale. The most important quantum effects turn out to be the modification of the leptonic couplings of the vector boson Z and the generation of a purely leptonic effective Lagrangian. Large LFU breaking effects in Z and tau decays and visible lepton flavour violating (LFV) effects in the processes tau -> mu ll, tau -> mu rho, tau -> mu pi and tau -> mu eta^(') are induced.
Implication of Higgs mediated Flavour Changing Neutral Currents with Minimal Flavour Violation
Rebelo, M N
2015-01-01
We analise phenomenological implications of two Higgs doublet models with Higgs flavour changing neutral currents suppressed in the quark sector by small entries of the Cabibbo-Kokayashi-Maskawa matrix. This suppression occurs in a natural way since it is the result of a symmetry applied to the Lagrangian. These type of models were proposed some time ago by Branco Grimus and Lavoura. Our results clearly show that these class of models allow for new physical scalars, with masses which are reachable at the LHC. The imposed symmetry severely reduces the number of free parameters and allows for predictions. Therefore these models can eventually be proved right or eliminated experimentally.
A minimal seesaw model with mu-tau symmetry
Jurciukonis, Darius; Juodagalvis, Andrius
2015-01-01
We analyse a flavour model for a lepton sector which is based on type I seesaw mechanism, a Z_2 symmetry for lepton flavours, a mu-tau interchange symmetry and a CP symmetry. This model fits well the data of neutrino mass squared differences and oscillation angles. The model predicts an overall neutrino mass scale for normal and inverted neutrino mass hierarchy and the effective mass m_beta, which is used in the neutrinoless double beta decay.
DEFF Research Database (Denmark)
Ravasio, Davide Antonio
Fungi produce a variety of volatile organic compounds (VOCs) during their primary or secondary metabolism and with a wide range of functions. The main focus of this research work has been put on flavour molecules that are produced during fermentation processes, mainly esters and alcohols derived...
Symmetries, Symmetry Breaking, Gauge Symmetries
Strocchi, Franco
2015-01-01
The concepts of symmetry, symmetry breaking and gauge symmetries are discussed, their operational meaning being displayed by the observables {\\em and} the (physical) states. For infinitely extended systems the states fall into physically disjoint {\\em phases} characterized by their behavior at infinity or boundary conditions, encoded in the ground state, which provide the cause of symmetry breaking without contradicting Curie Principle. Global gauge symmetries, not seen by the observables, are nevertheless displayed by detectable properties of the states (superselected quantum numbers and parastatistics). Local gauge symmetries are not seen also by the physical states; they appear only in non-positive representations of field algebras. Their role at the Lagrangian level is merely to ensure the validity on the physical states of local Gauss laws, obeyed by the currents which generate the corresponding global gauge symmetries; they are responsible for most distinctive physical properties of gauge quantum field ...
Two-Higgs Leptonic Minimal Flavour Violation
Botella, F J; Nebot, M; Rebelo, M N
2011-01-01
We construct extensions of the Standard Model with two Higgs doublets, where there are flavour changing neutral currents both in the quark and leptonic sectors, with their strength fixed by the fermion mixing matrices $V_{CKM}$ and $V_{PMNS}$. These models are an extension to the leptonic sector of the class of models previously considered by Branco, Grimus and Lavoura, for the quark sector. We consider both the cases of Dirac and Majorana neutrinos and identify the minimal discrete symmetry required in order to implement the models in a natural way.
Gauge Invariants and Correlators in Flavoured Quiver Gauge Theories
Mattioli, Paolo
2016-01-01
In this paper we study the construction of holomorphic gauge invariant operators for general quiver gauge theories with flavour symmetries. Using a characterisation of the gauge invariants in terms of equivalence classes generated by permutation actions, along with representation theory results in symmetric groups and unitary groups, we give a diagonal basis for the 2-point functions of holomorphic and anti-holomorphic operators. This involves a generalisation of the previously constructed Quiver Restricted Schur operators to the flavoured case. The 3-point functions are derived and shown to be given in terms of networks of symmetric group branching coefficients. The networks are constructed through cutting and gluing operations on the quivers.
Institute of Scientific and Technical Information of China (English)
ZHOUBang-Rong
2003-01-01
High density phase transitions in a 4-dimensional Nambu-dona-Lasinio model containing a single symmetry breaking order parameter coming from the fermion-antifermion condensates are researched and expounded by means of both the gap equation and the effective potential approach. The phase transitions are proven to be second-order at a high temperature T; however at T = 0 they are first- or second-order, depending on whether A/m(0), the ratio of the momentum cutoff A in the fermion-loop integrals to the dynamical fermion mass m(0) at zero temperature, is lessthan 3.387 or not. The former condition cannot be satisfied in some models. The discussions further show complete effectiveness of the critical analysis based on the gap equation for second order phase transitions including determination of the condition of their occurrence.
Institute of Scientific and Technical Information of China (English)
ZHOU Bang-Rong
2003-01-01
High density phase transitions in a 4-dimensional Nambu-Jona-Lasinio model containing a single symmetry breaking order parameter coming from the fermion-antifermion condensates are researched and expounded by means of both the gap equation and the effective potential approach. The phase transitions are proven to be second-order at a high temperature T; however at T = 0 they are first- or second-order, depending on whether A/m(0), the ratio of the momentum cutoff A in the fermion-loop integrals to the dynamicalfermion mass m(0) at zero temperature, is less than 3.387 or not. The former condition cannot be satisfied in some models. The discussions further show complete effectiveness of the critical analysis based on the gap equation for second order phase transitions including determination of the condition of their occurrence.
Charged-lepton flavour physics
Indian Academy of Sciences (India)
Andreas Hoecker
2012-11-01
This write-up on a talk at the 2011 Lepton–Photon symposium in Mumbai, India, summarizes recent results in the charged-lepton flavour sector. Searches for charged-lepton flavour violation, lepton electric dipole moments and flavour-conserving CP violation are reviewed here. Recent progress in -lepton physics and in the Standard Model prediction of the muon anomalous magnetic moment is also discussed.
Neutrino mass and mixing with discrete symmetry
King, Stephen F.; Luhn, Christoph
2013-05-01
This is a review paper about neutrino mass and mixing and flavour model building strategies based on discrete family symmetry. After a pedagogical introduction and overview of the whole of neutrino physics, we focus on the PMNS mixing matrix and the latest global fits following the Daya Bay and RENO experiments which measure the reactor angle. We then describe the simple bimaximal, tri-bimaximal and golden ratio patterns of lepton mixing and the deviations required for a non-zero reactor angle, with solar or atmospheric mixing sum rules resulting from charged lepton corrections or residual trimaximal mixing. The different types of see-saw mechanism are then reviewed as well as the sequential dominance mechanism. We then give a mini-review of finite group theory, which may be used as a discrete family symmetry broken by flavons either completely, or with different subgroups preserved in the neutrino and charged lepton sectors. These two approaches are then reviewed in detail in separate chapters including mechanisms for flavon vacuum alignment and different model building strategies that have been proposed to generate the reactor angle. We then briefly review grand unified theories (GUTs) and how they may be combined with discrete family symmetry to describe all quark and lepton masses and mixing. Finally, we discuss three model examples which combine an SU(5) GUT with the discrete family symmetries A4, S4 and Δ(96).
Fermion masses and mixing in $\\Delta(27)$ flavour model
Abbas, Mohammed
2014-01-01
An extension of the Standard Model (SM) based on the non-Abelian discrete group $\\Delta(27)$ is considered. The $\\Delta(27)$ flavour symmetry is spontaneously broken only by gauge singlet scalar fields, therefore our model is free from any flavour changing neural current. We show that the model accounts simultaneously for the observed quark and lepton masses and their mixing. In the quark sector, we find that the up quark mass matrix is flavour diagonal and the Cabbibo-Kobayashi-Maskawa (CKM) mixing matrix arises from down quarks. In the lepton sector, we show that the charged lepton mass matrix is almost diagonal. We also adopt type-I seesaw mechanism to generate neutrino masses. A deviated mixing matrix from tri-bimaximal Maki-Nakagawa-Sakata (MNS), with $\\sin\\theta_{13} \\sim 0.13$ and $\\sin^2 \\theta_{23} \\sim 0.41$, is naturally produced.
Flavour Tagging with the LHCb experiment
Birnkraut, Alex
2015-01-01
Measurements of flavour oscillations and time-dependent CP asymmetries in neutral B meson systems require knowledge of the b quark production flavour. This identification is performed by the Flavour Tagging.
Flavour Changing Higgs Couplings in a Class of Two Higgs Doublet Models
Botella, F J; Nebot, M; Rebelo, M N
2015-01-01
We analyse various flavour changing processes like $t\\to hu,hc$, $h\\to \\tau e,\\tau\\mu$ as well as hadronic decays $h\\to bs,bd$, in the framework of a class of two Higgs doublet models where there are flavour changing neutral scalar currents at tree level. These models have the remarkable feature of having these flavour-violating couplings entirely determined by the CKM and PMNS matrices as well as $\\tan\\beta$. The flavour structure of these scalar currents results from a symmetry of the Lagrangian and therefore it is natural and stable under the renormalization group. We show that in some of the models the rates of the above flavour changing processes can reach the discovery level at the LHC at 13 TeV even taking into account the stringent bounds on low energy processes, in particular $\\mu\\to e\\gamma$.
Flavour-changing Higgs couplings in a class of two Higgs doublet models
Energy Technology Data Exchange (ETDEWEB)
Botella, F.J. [Universitat de Valencia-CSIC, Departament de Fisica Teorica y IFIC, Burjassot (Spain); Branco, G.C. [Universitat de Valencia-CSIC, Departament de Fisica Teorica y IFIC, Burjassot (Spain); Instituto Superior Tecnico (IST), Lisboa Univ., Departamento de Fisica and Centro de Fisica Teorica de Particulas (CFTP), Lisbon (Portugal); Nebot, M. [Instituto Superior Tecnico (IST), Lisboa Univ., Centro de Fisica Teorica de Particulas (CFTP), Lisbon (Portugal); Rebelo, M.N. [Instituto Superior Tecnico (IST), Lisboa Univ., Departamento de Fisica and Centro de Fisica Teorica de Particulas (CFTP), Lisbon (Portugal)
2016-03-15
We analyse various flavour-changing processes like t → hu, hc, h → τe, τμ as well as hadronic decays h @→ bs, bd, in the framework of a class of two Higgs doublet models where there are flavour-changing neutral scalar currents at tree level. These models have the remarkable feature of having these flavour-violating couplings entirely determined by the CKM and PMNS matrices as well as tan β. The flavour structure of these scalar currents results from a symmetry of the Lagrangian and there fore it is natural and stable under the renormalisation group. We show that in some of the models the rates of the above flavour-changing processes can reach the discovery level at the LHC at 13 TeV even taking into account the stringent bounds on low energy processes, in particular μ @→ eγ. (orig.)
Dark matter and observable Lepton Flavour Violation
Heurtier, Lucien
2016-01-01
Seesaw models with leptonic symmetries allow right-handed (RH) neutrino masses at the electroweak scale, or even lower, at the same time having large Yukawa couplings with the Standard Model leptons, thus yielding observable effects at current or near-future lepton-flavour-violation (LFV) experiments. These models have been previously considered also in connection to low-scale leptogenesis, but the combination of observable LFV and successful leptogenesis has appeared to be difficult to achieve unless the leptonic symmetry is embedded into a larger one. In this paper, instead, we follow a different route and consider a possible connection between large LFV rates and Dark Matter (DM). We present a model in which the same leptonic symmetry responsible for the large Yukawa couplings guarantees the stability of the DM candidate, identified as the lightest of the RH neutrinos. The spontaneous breaking of this symmetry, caused by a Majoron-like field, also provides a mechanism to produce the observed relic density ...
Flavour Physics and CP Violation
Pich, Antonio
2013-01-01
An introductory overview of the Standard Model description of flavour is presented. The main emphasis is put on present tests of the quark-mixing matrix structure and the phenomenological determination of its parameters. Special attention is given to the experimental evidences of CP violation and their important role in our understanding of flavour dynamics.
Anarchic Yukawas and top partial compositeness: the flavour of a successful marriage
Cacciapaglia, Giacomo; Flacke, Thomas; Lee, Seung J; Parolini, Alberto; Serôdio, Hugo
2015-01-01
The top quark can be naturally singled out from other fermions in the Standard Model due to its large mass, of the order of the electroweak scale. We follow this reasoning in models of pseudo Nambu Goldstone Boson composite Higgs, which may derive from an underlying confining dynamics. We consider a new class of flavour models, where the top quark obtains its mass via partial compositeness, while the lighter fermions acquire their masses by a deformation of the dynamics generated at a high flavour scale. One interesting feature of such scenario is that it can avoid all the flavour constraints without the need of flavour symmetries, since the flavour scale can be pushed high enough. We show that both flavour conserving and violating constraints can be satisfied with top partial compositeness without invoking any flavour symmetry for the up-type sector, in the case of the minimal SO(5)/SO(4) coset with top partners in the four-plet and singlet of SO(4). In the down-type sector, some degree of alignment is requi...
Anarchic Yukawas and top partial compositeness: the flavour of a successful marriage
Cacciapaglia, Giacomo; Cai, Haiying; Flacke, Thomas; Lee, Seung J.; Parolini, Alberto; Serôdio, Hugo
2015-06-01
The top quark can be naturally singled out from other fermions in the Standard Model due to its large mass, of the order of the electroweak scale. We follow this reasoning in models of pseudo Nambu Goldstone Boson composite Higgs, which may derive from an underlying confining dynamics. We consider a new class of flavour models, where the top quark obtains its mass via partial compositeness, while the lighter fermions acquire their masses by a deformation of the dynamics generated at a high flavour scale. One interesting feature of such scenario is that it can avoid all the flavour constraints without the need of flavour symmetries, since the flavour scale can be pushed high enough. We show that both flavour conserving and violating constraints can be satisfied with top partial compositeness without invoking any flavour symmetry for the up-type sector, in the case of the minimal SO(5)/SO(4) coset with top partners in the four-plet and singlet of SO(4). In the down-type sector, some degree of alignment is required if all down-type quarks are elementary. We show that taking the bottom quark partially composite provides a dynamical explanation for the hierarchy causing this alignment. We present explicit realisations of this mechanism which do not require to include additional bottom partner fields. Finally, these conclusions are generalised to scenarios with non-minimal cosets and top partners in larger representations.
Quark Yukawa pattern from spontaneous breaking of flavour $SU(3)^3$
Nardi, Enrico
2015-01-01
A $SU(3)_Q \\times SU(3)_u \\times SU(3)_d$ invariant scalar potential breaking spontaneously the quark flavour symmetry can explain the standard model flavour puzzle. The approximate alignment in flavour space of the vacuum expectation values of the up and down `Yukawa fields' results as a dynamical effect. The observed quark mixing angles, the weak CP violating phase, and hierarchical quark masses can be all reproduced at the cost of introducing additional (auxiliary) scalar multiplets, but without the need of introducing hierarchical parameters.
Lepton Flavour Violation in a Left-Right Symmetric Model
Pastor, S; Valle, José W F; Pastor, Sergio; Rindani, Saurabh D.; Valle, Jose W.F.
1999-01-01
We consider in this paper a Left-Right symmetric gauge model in which a global lepton-number-like symmetry is introduced and broken spontaneously at a scale that could be as low as 10^4 GeV or so. The corresponding physical Nambu-Goldstone boson, which we call majoron and denote J, can have tree-level flavour-violating couplings to the charged fermions, leading to sizeable majoron-emitting lepton-flavour-violating weak decays. We consider explicitly a leptonic variant of the model and show that the branching ratios for \\mu -> e+J, \\tau -> e+J and \\tau -> \\mu+J decays can be large enough to fall within the sensitivities of future \\mu and \\tau factories. On the other hand the left-right gauge symmetry breaking scale may be as low as few TeV.
Food contact materials, flavouring substances and smoke flavourings
Directory of Open Access Journals (Sweden)
Engel K-H
2012-10-01
Full Text Available
The EFSA Panel on Food Additives, Flavourings, Processing Aids and Materials in Contact with Food (AFC Panel and the subsequent Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF Panel have undertaken evaluations of the safety of flavourings (both chemically defined substances and mixtures such as smoke flavourings and food contact materials (FCM, as well as assessments on other substances used in food. The major progress in methodologies for the evaluation of the safety of these substances is highlighted in this article. By December 2011, scientific opinions had been adopted for 247 substances for food contact materials, mainly plastics. Adoption of a series of opinions on active and/or intelligent packaging substances and on recycling processes of plastics is planned between July 2012 and December 2013. Panel opinions, EFSA statements/reports and guidance documents were published on specific issues and on substances for which there was an urgent request for safety evaluation (for example isopropylthioxanthone (ITX, bisphenol A (BPA, phthalates, epoxidised soybean oil (ESBO, benzophenone and 4-methylbenzophenone. By 2009, the AFC and CEF Panels had completed the safety review of 2 067 flavourings substances used in the EU. Additional data, which were requested for 404 substances, are currently under evaluation or have been generated. Eleven smoke flavourings have been evaluated, and the CEF Panel has prepared a guidance document on the future data required for the evaluation of flavourings.
Flavour in supersymmetric Grand Unification a democratic approach
Barbieri, Riccardo; Dvali, Gia; Hall, L; Strumia, A
1994-01-01
We consider the flavour problem in a supersymmetric Grand Unified theory with gauged SU(6) group, where the Higgs doublets are understood as pseudo-Goldstone bosons of a larger $\\SU(6)\\otimes\\SU(6)$ global symmetry of the Higgs superpotential. A key element of this work is that we never appeal to any flavour symmetry. One main interesting feature emerges: only one of the light fermions, an up-type quark, to be identified with the top, can get a Yukawa coupling at renormalizable level. This fact, together with bottom-tau Yukawa unification, also implied in our scheme, gives rise to a characteristic correlation between the top and the Higgs mass. By including a flavour-blind discrete symmetry and requiring that all higher dimensional operators be mediated by the exchange of appropriate heavy multiplets, it is possible to give an approximate description of all masses and mixing angles in term of a hierarchy of grand unified scales. A special ``texture'' arises, implying a relation between the top mass and the th...
B decays and lepton flavour (universality) violation
Crivellin, A.
2016-07-01
LHCb found hints for physics beyond the standard model in Bto K^*μ^+μ^- , Bto K^*μ^+μ^-/Bto K^*e^+e^- and B_stoφμ^+μ^- . In addition, the BABAR results for Bto D^{(*)}τν and the CMS excess in htoτ^±μ^∓ also point towards lepton flavour (universality) violating new physics. While Bto D^{(*)}τν and htoτ^±μ^∓ can be naturally explained by an extended Higgs sector, the probably most promising explanation for the bto sμμ anomalies is a Z' boson. Furthermore, combining a 2HDM with a gauged L_μ-L_τ symmetry allows for explaining the bto sμ^+μ^- anomalies and htoτ^±μ^∓ simultaneously, with interesting correlations to τto3μ . In the light of these deviations from the SM we also discuss the possibilities of observing lepton flavour violating B decays ( e.g. Bto K^{(*)}τ^±μ^∓ and B_stoτ^±μ^∓ in Z^' models.
Flavour chemicals in electronic cigarette fluids
Tierney, Peyton A; Karpinski, Clarissa D; Jessica E Brown; Luo, Wentai; Pankow, James F.
2015-01-01
Background Most e-cigarette liquids contain flavour chemicals. Flavour chemicals certified as safe for ingestion by the Flavor Extracts Manufacturers Association may not be safe for use in e-cigarettes. This study identified and measured flavour chemicals in 30 e-cigarette fluids. Methods Two brands of single-use e-cigarettes were selected and their fluids in multiple flavour types analysed by gas chromatography/mass spectrometry. For the same flavour types, and for selected confectionary fla...
CP violation versus flavour in supersymmetric theories
Abel, S.; Branco, G. C.; Khalil, S.
2003-09-01
We show that the quark flavour structure and CP violating phenomena are strongly correlated in supersymmetric theories. For a generic pattern of supersymmetry breaking the two broad categories of Yukawa couplings, democratic and hierarchical textures, have entirely different phenomenological implications. With hierarchical Yukawas, the rephasing invariant phase, arg(VusVcbVcb∗Vcs∗), in the CKM mixing matrix has to be of order unity, while the SUSY CP violating phases are severely constrained by electric dipole moments, giving rise to the so-called SUSY CP problem. With democratic Yukawas, all experimental CP results can be accommodated with small values for the CKM and SUSY CP violating phases (i.e., CP can be considered as an approximate symmetry at the high energy scale). We also show that within this scenario, an entirely real CKM matrix in supersymmetric models is still allowed by the present experimental results.
CP violation versus flavour in supersymmetric theories
Abel, S A; Khalil, S
2003-01-01
We show that the quark flavour structure and CP violating phenomena are strongly correlated in supersymmetric theories. For a generic pattern of supersymmetry breaking the two broad categories of Yukawa couplings, democratic and hierarchical textures, have entirely different phenomenological implications. With hierarchical Yukawas, the rephasing invariant phase, arg(V_us V_cb V_cb^* V_cs^*), in the CKM mixing matrix has to be of order unity, while the SUSY CP violating phases are severely constrained by electric dipole moments, giving rise to the so-called SUSY CP problem. With democratic Yukawas, all experimental CP results can be accommodated with small values for the CKM and SUSY CP violating phases (i.e., CP can be considered as an approximate symmetry at the high energy scale). We also show that within this scenario, an entirely real CKM matrix in supersymmetric models is still allowed by the present experimental results.
Heavy flavour results from ATLAS
Directory of Open Access Journals (Sweden)
Bell P. J.
2012-06-01
Full Text Available A selection of heavy-flavour physics results from the ATLAS experiment is presented, based on data collected in proton-proton collisions at the LHC during 2010. Differential cross-sections for the production of heavy flavours, charmonium and bottomonium states and D-mesons are presented and compared to various theoretical models. Results of B-hadron lifetime measurements are also reported.
Symmetries and Symmetry Breaking
Van Oers, W T H
2003-01-01
In understanding the world of matter, the introduction of symmetry principles following experimentation or using the predictive power of symmetry principles to guide experimentation is most profound. The conservation of energy, linear momentum, angular momentum, charge, and CPT involve fundamental symmetries. All other conservation laws are valid within a restricted subspace of the four interactions: the strong, the electromagnetic, the weak, and the gravitational interaction. In this paper comments are made regarding parity violation in hadronic systems, charge symmetry breaking in two nucleon and few nucleon systems, and time-reversal-invariance in hadronic systems.
S4 as a natural flavor symmetry for lepton mixing
Bazzocchi, Federica
2008-01-01
Group theoretical motivations seem to indicate the discrete symmetry S4 as the minimal flavour symmetry compatible with tribimaximal neutrino mixing. We prove in a model independent way that indeed S4 can realize exact TriBimaximal mixing through different symmetry breaking patterns. We present two models in which lepton TriBimaximal mixing is realized in different ways and for each one we discuss the superpotential that leads to the correct breaking of the flavor symmetry.
Radiatively induced flavour violation in the general two-Higgs doublet model with Yukawa alignment
International Nuclear Information System (INIS)
The most general two-Higgs doublet model contains new sources of flavour violation that are usually in conflict with the experimental constraints. One possibility to suppress the exotic contribution to the flavour changing neutral currents consists on imposing the alignment of the Yukawa couplings. This condition presumably holds at a high-energy scale and is spoiled by the radiative corrections. We compute in this Letter the size of the radiatively induced flavour violating Higgs couplings at the electroweak scale. These also yield the absolute lower bound on the size of the exotic contributions to the flavour changing neutral currents in any two-Higgs doublet model, barring cancellations and the existence of discrete symmetries. We show that these contributions are well below the experimental bounds in large regions of the parameter space.
A 125 GeV composite Higgs boson versus flavour and electroweak precision tests
Barbieri, Riccardo; Sala, Filippo; Straub, David M; Tesi, Andrea
2012-01-01
A composite Higgs boson of 125 GeV mass, only mildly fine-tuned, requires top partners with a semi-perturbative coupling and a mass not greater than about a TeV. We analyze the strong constraints on such picture arising from flavour and electroweak precision tests in models of partial compositeness. We consider different representations for the composite fermions and compare the case of an anarchic flavour structure to models with a U(3)^3 and U(2)^3 flavour symmetry. Although non trivially, some models emerge that look capable of accommodating a 125 GeV Higgs boson with top partners in an interesting mass range for discovery at the LHC as well as associated flavour signals.
A Grand Delta(96) x SU(5) Flavour Model
King, Stephen F; Stuart, Alexander J
2012-01-01
Recent results from the Daya Bay and RENO reactor experiments have measured the smallest lepton mixing angle and found it to have a value of theta_13 approximately 9 degrees. This result presents a new challenge for the existing paradigms of discrete flavour symmetries which attempt to describe all quark and lepton masses and mixing angles. Here we propose a Supersymmetric Grand Unified Theory of Flavour based on Delta(96) x SU(5), together with a U(1) x Z3 symmetry, including a full discussion of Delta(96) in a convenient basis. The Grand Delta(96) x SU(5) Flavour Model relates the quark mixing angles and masses in the form of the Gatto-Sartori-Tonin relation and realises the Georgi-Jarlskog mass relations between the charged leptons and down-type quarks. We predict a Bi-trimaximal (not Tri-bimaximal) form of neutrino mixing matrix, which, after including charged lepton corrections with zero phase, leads to the following GUT scale predictions for the atmospheric, solar, and reactor mixing angles: theta_23=36...
Non-universal Z' models with protected flavour-changing interactions
Jung, Martin
2016-01-01
We define a new class of Z' models with neutral flavour-changing interactions at tree level in the down-quark sector. They are related in an exact way to elements of the quark mixing matrix due to an underlying flavoured U(1)' gauge symmetry, rendering these models particularly predictive. The same symmetry implies lepton-flavour non-universal couplings, fully determined by the gauge structure of the model. Our models allow to address several presently observed deviations from the SM and specific correlations among the new physics contributions to the Wilson coefficients C9,10(l) can be tested in b->sll transitions. We furthermore predict lepton-universality violations in Z' decays, testable at the LHC.
Light third-generation squarks from flavour gauge messengers
International Nuclear Information System (INIS)
We study models of gauge-mediated supersymmetry breaking with a gauged horizontal SU(3)F symmetry acting on the quark superfields. If SU(3)F is broken non-supersymmetrically by F-term vacuum expectation values, the massive gauge bosons and gauginos become messengers for SUSY breaking mediation. These gauge messenger fields induce a flavour-dependent, negative contribution to the soft masses of the squarks at one loop. In combination with the soft terms from standard gauge mediation, one obtains large and degenerate first- and second-generation squark masses, while the stops and sbottoms are light. We discuss the implications of this mechanism for the superparticle spectrum and for flavour precision observables. We also provide an explicit realization in a model with simultaneous SUSY and SU(3)F breaking
Light third-generation squarks from flavour gauge messengers
Energy Technology Data Exchange (ETDEWEB)
Bruemmer, Felix [International School for Advanced Studies, Trieste (Italy); Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); McGarrie, Moritz [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Univ. of the Witwatersrand, Johannesburg (South Africa). School of Physics and Centre for Theoretical Physics; Weiler, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); CERN - European Organization for Nuclear Research, Geneva (Switzerland). Theory Div.
2014-04-15
We study models of gauge-mediated supersymmetry breaking with a gauged horizontal SU(3){sub F} symmetry acting on the quark superfields. If SU(3){sub F} is broken non-supersymmetrically by F-term vacuum expectation values, the massive gauge bosons and gauginos become messengers for SUSY breaking mediation. These gauge messenger fields induce a flavour-dependent, negative contribution to the soft masses of the squarks at one loop. In combination with the soft terms from standard gauge mediation, one obtains large and degenerate first- and second-generation squark masses, while the stops and sbottoms are light. We discuss the implications of this mechanism for the superparticle spectrum and for flavour precision observables. We also provide an explicit realization in a model with simultaneous SUSY and SU(3){sub F} breaking.
Light third-generation squarks from flavour gauge messengers
Energy Technology Data Exchange (ETDEWEB)
Brümmer, Felix [SISSA/ISAS,Via Bonomea 265, Trieste I-34136 (Italy); Deutsches Elektronen-Synchrotron DESY,Notkestrasse 85, D-22607 Hamburg (Germany); McGarrie, Moritz [Deutsches Elektronen-Synchrotron DESY,Notkestrasse 85, D-22607 Hamburg (Germany); National Institute for Theoretical Physics, School of Physics,and Centre for Theoretical Physics, University of the Witwatersrand,Johannesburg, WITS 2050 (South Africa); Weiler, Andreas [Deutsches Elektronen-Synchrotron DESY,Notkestrasse 85, D-22607 Hamburg (Germany); CERN Theory Division,CH-1211 Geneva 23 (Switzerland)
2014-04-10
We study models of gauge-mediated supersymmetry breaking with a gauged horizontal SU(3){sub F} symmetry acting on the quark superfields. If SU(3){sub F} is broken non-supersymmetrically by F-term vacuum expectation values, the massive gauge bosons and gauginos become messengers for SUSY breaking mediation. These gauge messenger fields induce a flavour-dependent, negative contribution to the soft masses of the squarks at one loop. In combination with the soft terms from standard gauge mediation, one obtains large and degenerate first- and second-generation squark masses, while the stops and sbottoms are light. We discuss the implications of this mechanism for the superparticle spectrum and for flavour precision observables. We also provide an explicit realization in a model with simultaneous SUSY and SU(3){sub F} breaking.
Heavy flavour at the Large Hadron Collider
Gibson, V
2013-01-01
Heavy flavour physics provides a crucial role in the validation of the Standard Model of particle physics and in the search for new phenomena beyond. This review provides a personal summary of the headline results as of May 2013 from the LHC heavy flavour community in the subject areas of heavy flavour production and spectroscopy, mixing and CP violation and rare decays.
Aspects of the Flavour Expansion Theorem
Paraskevas, M
2015-01-01
The Flavour Expansion Theorem, which has been recently proposed as a more general and elegant algebraic method, for the derivation of the commonly used Mass Insertion Approximation, is revisited. The theorem is reviewed, with respect to its straightforward applications in Flavour physics, and compared against the standard diagrammatic flavour basis techniques, in cases where the latter become inadequate.
Cordente, Antonio G.; Curtin, Christopher D.; Varela, Cristian; Pretorius, Isak S.
2012-01-01
The flavour of fermented beverages such as beer, cider, saké and wine owe much to the primary fermentation yeast used in their production, Saccharomyces cerevisiae. Where once the role of yeast in fermented beverage flavour was thought to be limited to a small number of volatile esters and higher alcohols, the discovery that wine yeast release highly potent sulfur compounds from non-volatile precursors found in grapes has driven researchers to look more closely at how choice of yeast can infl...
Dynamical generation of flavour
Indian Academy of Sciences (India)
Charanjit Kaur Khosa
2016-02-01
We propose the generation of Standard Model fermion hierarchy by the extension of renormalizable SO(10) GUT with O(Ng) family gauge symmetry. In this scenario, Higgs representations of SO(10) also carry family indices and are called Yukawons. Vacuum expectation values of these Yukawon fields break GUT and family symmetry and generate MSSM Yukawa couplings dynamically. We have demonstrated this idea using $10 \\oplus 210 \\oplus 126 \\oplus \\overline{126}$ Higgs irrep, ignoring the contribution of 120-plet which is, however, required for complete fitting of fermion mass-mixing data. The effective MSSM matter fermion couplings to the light Higgs pair are determined by the null eigenvectors of the MSSM-type Higgs doublet superfield mass matrix $\\mathcal{H}$. A consistency condition on the doublet ([1, 2,±1]) mass matrix (Det($\\mathcal{H}$) = 0) is required to keep one pair of Higgs doublets light in the effective MSSM. We show that the Yukawa structure generated by null eigenvectors of $\\mathcal{H}$ are of generic kind required by the MSSM. A hidden sector with a pair of (Sab; ab) fields breaks supersymmetry and facilitates DO(Ng) = 0. SUSY breaking is communicated via supergravity. In this scenario, matter fermion Yukawa couplings are reduced from 15 to just 3 parameters in MSGUT with three generations.
Heavy flavours: working group summary
Energy Technology Data Exchange (ETDEWEB)
Ali, Ahmed [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Gladilin, Leonid [Moscow State Univ. (Russian Federation). Scobeltsyn Inst. of Nuclear Physics; Tonelli, Diego [Fermi National Accelerator Lab., Batavia, IL (United States)
2009-07-15
The talks presented in the working group ''Heavy flavours'' of the DIS 2009 workshop are summarised. New and recently updated results from theory, proton antiproton and heavy ion colliders, as well from HERA and e{sup +}e{sup -} colliders are discussed. (orig.)
Flavour physics and CP violation
Indian Academy of Sciences (India)
Rukmani Mohanta; Anjan Kumar Giri
2010-05-01
It is well known that the study of flavour physics and CP violation is very important to critically test the Standard Model and to look for possible signature of new physics beyond it. The observation of CP violation in kaon system in 1964 has ignited a lot of experimental and theoretical efforts to understand its origin and to look for CP violation effects in other systems besides the neutral kaons. The two -factories BABAR and BELLE, along with other experiments, in the last decade or so made studies in flavour physics and CP violation a very interesting one. In this article we discuss the status and prospectives of the flavour physics associated with the strange, charm and bottom sectors of the Standard Model. The important results in kaon sector will be briefly discussed. Recently, mixing in the charm system has been observed, which was being pursued for quite some time without any success. The smallness of the mixing parameters in the charm system is due to the hierarchical structure of the CKM matrix. Interestingly, so far we have not found CP violation in the charm system but in the future, with more dedicated experiments at charm threshold, the situation could change. Many interesting observations have been made in the case of bottom mesons and some of them show some kind of deviations from that of the Standard Model expectations which are mainly associated with the → flavour changing neutral current transitions. It is long believed that the system could be the harbinger of new physics since it is a system in which both bottom and strange quarks are the constituents. Recently, D0 and CDF announced their result for the mixing which is claimed to be the first possible new physics signature in the flavour sector. We plan to touch upon all important issues pointing out both theoretical and experimental developments and future prospects in this review article.
Relating quarks and leptons with the T7 flavour group
Directory of Open Access Journals (Sweden)
Cesar Bonilla
2015-03-01
Full Text Available In this letter we present a model for quarks and leptons based on T7 as flavour symmetry, predicting a canonical mass relation between charged leptons and down-type quarks proposed earlier. Neutrino masses are generated through a Type-I seesaw mechanism, with predicted correlations between the atmospheric mixing angle and neutrino masses. Compatibility with oscillation results leads to lower bounds for the lightest neutrino mass as well as for the neutrinoless double beta decay rates, even for normal neutrino mass hierarchy.
Chiral order and fluctuations in multi-flavour QCD
Descotes-Genon, S; Stern, J
2003-01-01
Multi-flavour (N_f>=3) Chiral Perturbation Theory (ChPT) may exhibit instabilities due to vacuum fluctuations of sea q-bar q pairs. Keeping the fluctuations small would require a very precise fine-tuning of the low-energy constants L_4 and L_6 to L_4[crit](M_rho) = - 0.51 * 10^(-3), and L_6[crit](M_rho) = - 0.26 * 10^(-3). A small deviation from these critical values -- like the one suggested by the phenomenology of OZI-rule violation in the scalar channel -- is amplified by huge numerical factors inducing large effects of vacuum fluctuations. This would lead in particular to a strong N_f-dependence of chiral symmetry breaking and a suppression of multi-flavour chiral order parameters. A simple resummation is shown to cure the instability of N_f>=3 ChPT, but it modifies the standard expressions of some O(p^2) and O(p^4) low-energy parameters in terms of observables. On the other hand, for r=m_s/m > 15, the two-flavour condensate is not suppressed, due to the contribution induced by massive vacuum s-bar s pair...
Flavour alignment in physics beyond the standard model
Energy Technology Data Exchange (ETDEWEB)
Braeuninger, Carolin Barbara
2012-11-21
There are numerous reasons to think that the Standard Model of physics is not the ultimate theory of nature on very small scales. However, attempts to construct theories that go beyond the Standard Model generically lead to high rates of flavour changing neutral processes that are in conflict with experiment: Quarks are the fundamental constituents of protons and neutrons. Together with electrons they form the visible matter of the universe1. They come in three generations or ''flavours''. In interactions, quarks of different generations can mix, i.e. a quark of one flavour can transform into a quark of another flavour. In the Standard Model, at first order in perturbation theory, such processes occur only via the exchange of a charged particle. Flavour changing neutral processes can only arise in processes involving loops of charged particles. This is due to the fact that all couplings of two quarks to a neutral particle are diagonal in the basis of the mass eigenstates of the quarks. There is thus no mixing of quarks of different flavour at first order. Since the loop processes are suppressed by a loop factor, the Standard Model predicts very low rates for neutral processes that change the flavour of quarks. So far, this is in agreement with experiment. In extensions of the Standard Model, new couplings to the quarks are usually introduced. In general there is no reason why the new coupling matrices should be diagonal in the mass basis of the quarks. These models therefore predict high rates for processes that mix quarks of different flavour. Extensions of the Standard Model must therefore have a non-trivial flavour structure. A possibility to avoid flavour violation is to assume that the new couplings are aligned with the mass matrices of the quarks, i.e. diagonal in the same basis. This alignment could be due to a flavour symmetry. In this thesis, two extensions of the Standard Model with alignment are studied. The first is a simple
A flavour of family symmetries in a family of flavour models
Adelhart Toorop, Reinier de
2012-01-01
The Standard Model of Particle Physics has many (19) free parameters, most of which (13) are related to the masses and mixing angles of the elementary fermions (quarks and leptons). If we include neutrino masses, even 22 of the 28 parameters are related to the fermion mass sector. Although these par
Approaching Minimal Flavour Violation from an S4 x SU(5) SUSY GUT
Dimou, Maria; Luhn, Christoph
2015-01-01
We show how approximate Minimal Flavour Violation (MFV) can emerge from an SU(5) Supersymmetric Grand Unified Theory (SUSY GUT) supplemented by an S4 x U(1) family symmetry, which provides a good description of all quark and lepton (including neutrino) masses, mixings and CP violation. Assuming a SUSY breaking mechanism which respects the family symmetry, we calculate in full explicit detail the low energy mass insertion parameters in the super-CKM basis, including the effects of canonical normalisation and renormalisation group running. We find that the very simple family symmetry S4 x U(1) is sufficient to approximately reproduce the effects of low energy MFV.
B-anomalies related to leptons and lepton flavour universality violation
Crivellin, Andreas
2016-01-01
Several experiments observed deviations from the Standard Model (SM) in the flavour sector: LHCb found a $4-5\\,\\sigma$ discrepancy compared to the SM in $b\\to s\\mu^+\\mu^-$ transitions (recently supported by an Belle analysis) and CMS reported a non-zero measurement of $h\\to\\mu\\tau$ with a significance of $2.4\\,\\sigma$. Furthermore, BELLE, BABAR and LHCb founds hints for the violation of flavour universality in $B\\to D^{(*)}\\tau\
Energy Technology Data Exchange (ETDEWEB)
Bruemmer, Felix [SISSA/ISAS, Trieste (Italy); Kraml, Sabine; Kulkarni, Suchita; Smith, Christopher [Universite Grenoble-Alpes, CNRS/IN2P3, Laboratoire de Physique Subatomique et de Cosmologie, Grenoble Cedex (France)
2014-09-15
An inverted mass hierarchy in the squark sector, as in so-called ''natural supersymmetry'', requires non-universal boundary conditions at the mediation scale of supersymmetry breaking. We propose a formalism to define such boundary conditions in a basis-independent manner and apply it to generic scenarios where the third-generation squarks are light, while the first two-generation squarks are heavy and near-degenerate. We show that not only is our formalism particularly well suited to study such hierarchical squark mass patterns, but in addition the resulting soft terms at the TeV scale are manifestly compatible with the principle of minimal flavour violation, and thus automatically obey constraints from flavour physics. (orig.)
Flavour Physics with High-Luminosity Experiments
2016-01-01
With the first dedicated B-factory experiments BaBar (USA) and BELLE (Japan) Flavour Physics has entered the phase of precision physics. LHCb (CERN) and the high luminosity extension of KEK-B together with the state of the art BELLE II detector will further push this precision frontier. Progress in this field always relied on close cooperation between experiment and theory, as extraction of fundamental parameters often is very indirect. To extract the full physics information from existing and future data, this cooperation must be further intensified. This MIAPP programme aims in particular to prepare for this task by joining experimentalists and theorists in the various relevant fields, with the goal to build the necessary tools in face of the challenge of new large data sets. The programme will begin with a focus on physics with non-leptonic final states, continued by semileptonic B meson decays and Tau decays, and on various aspects of CP symmetry violation closer to the end. In addition, in the final ...
Flavour alignment in physics beyond the standard model
Energy Technology Data Exchange (ETDEWEB)
Braeuninger, Carolin Barbara
2012-11-21
There are numerous reasons to think that the Standard Model of physics is not the ultimate theory of nature on very small scales. However, attempts to construct theories that go beyond the Standard Model generically lead to high rates of flavour changing neutral processes that are in conflict with experiment: Quarks are the fundamental constituents of protons and neutrons. Together with electrons they form the visible matter of the universe1. They come in three generations or ''flavours''. In interactions, quarks of different generations can mix, i.e. a quark of one flavour can transform into a quark of another flavour. In the Standard Model, at first order in perturbation theory, such processes occur only via the exchange of a charged particle. Flavour changing neutral processes can only arise in processes involving loops of charged particles. This is due to the fact that all couplings of two quarks to a neutral particle are diagonal in the basis of the mass eigenstates of the quarks. There is thus no mixing of quarks of different flavour at first order. Since the loop processes are suppressed by a loop factor, the Standard Model predicts very low rates for neutral processes that change the flavour of quarks. So far, this is in agreement with experiment. In extensions of the Standard Model, new couplings to the quarks are usually introduced. In general there is no reason why the new coupling matrices should be diagonal in the mass basis of the quarks. These models therefore predict high rates for processes that mix quarks of different flavour. Extensions of the Standard Model must therefore have a non-trivial flavour structure. A possibility to avoid flavour violation is to assume that the new couplings are aligned with the mass matrices of the quarks, i.e. diagonal in the same basis. This alignment could be due to a flavour symmetry. In this thesis, two extensions of the Standard Model with alignment are studied. The first is a simple
Flavour Covariant Formalism for Resonant Leptogenesis
Dev, P S Bhupal; Pilaftsis, Apostolos; Teresi, Daniele
2014-01-01
We present a fully flavour-covariant formalism for transport phenomena and apply it to study the flavour-dynamics of Resonant Leptogenesis (RL). We show that this formalism provides a complete and unified description of RL, consistently accounting for three distinct physical phenomena: (i) resonant mixing and (ii) coherent oscillations between different heavy-neutrino flavours, as well as (iii) quantum decoherence effects in the charged-lepton sector. We describe the necessary emergence of higher-rank tensors in flavour space, arising from the unitarity cuts of partial self-energies. Finally, we illustrate the importance of this formalism within a minimal Resonant $\\tau$-Genesis model by showing that, with the inclusion of all flavour effects in a consistent way, the final lepton asymmetry can be enhanced by up to an order of magnitude, when compared to previous partially flavour-dependent treatments.
Patterns of Flavour Violation in the RSc Model, the LHT Model and Supersymmetric Flavour Models
Buras, Andrzej J
2009-01-01
We summarize the results on patterns of flavour violation in a Randall-Sundrum model with custodial protection (RSc) and compare them with those identified in the Littlest Higgs Model with T--parity (LHT) and in a number of SUSY Flavour Models. While K decays play in this presentation a prominent role, the inclusion of B physics and lepton flavour violation is crucial in the distinction between these three popular extensions of the Standard Model (SM) by means of flavour physics.
Phenomenological Implications of an S4 x SU(5) SUSY GUT of Flavour
Dimou, Maria; Luhn, Christoph
2015-01-01
We discuss the low energy phenomenological implications of an SU(5) Supersymmetric Grand Unified Theory (SUSY GUT) whose flavour structure is controlled by the family symmetry S4 x U(1), which provides a good description of all quark and lepton masses, mixings as well as CP violation. Although the model closely mimics Minimal Flavour Violation (MFV) as shown in arXiv:1511.07886, here we focus on the differences. We first present numerical estimates of the low energy mass insertion parameters, including canonical normalisation and renormalisation group running, for well-defined ranges of SUSY parameters and compare the naive model expectations to the numerical scans and the experimental bounds. Our results are then used to estimate the predictions for Electric Dipole Moments (EDMs), Lepton Flavour Violation (LFV), B and K meson mixing as well as rare B decays. The largest observable deviations from MFV come from the LFV process mu --> e gamma and the EDMs.
pi-pi and pi-K scatterings in three-flavour resummed chiral perturbation theory
Descotes-Genon, S
2008-01-01
The (light but not-so-light) strange quark may play a special role in the low-energy dynamics of QCD. The presence of strange quark pairs in the sea may have a significant impact of the pattern of chiral symmetry breaking : in particular large differences can occur between the chiral limits of two and three massless flavours (i.e., whether m_s is kept at its physical value or sent to zero). This may induce problems of convergence in three-flavour chiral expansions. To cope with such difficulties, we introduce a new framework, called Resummed Chiral Perturbation Theory. We exploit it to analyse pi-pi and pi-K scatterings and match them with dispersive results in a frequentist framework. Constraints on three-flavour chiral order parameters are derived.
Quark flavour observables in the Littlest Higgs model with T-parity after LHC Run 1
Blanke, Monika; Recksiegel, Stefan
2016-01-01
The Littlest Higgs Model with T-parity (LHT) belongs to the simplest new physics scenarios with new sources of flavour and CP violation. We present a new analysis of quark observables in the LHT model in view of the oncoming flavour precision era. We use all available information on the CKM parameters, lattice QCD input and experimental data on quark flavour observables and corresponding theoretical calculations, taking into account new lower bounds on the symmetry breaking scale and the mirror quark masses from the LHC. We investigate by how much the branching ratios for a number of rare $K$ and $B$ decays are still allowed to depart from their SM values. This includes $K^+\\to\\pi^+\
Heavy flavour production at CMS
Negro, Giulia
2016-01-01
Three recent results in heavy flavour production at the CMS experiment are addressed in this report. Measurements of the differential production cross sections of B hadron and quarkonium states in pp collisions at $\\sqrt{s} = 13$ TeV are presented. These are important tools to investigate heavy-quark production mechanisms in QCD. The dependences on transverse momentum and rapidity are investigated and comparisons with theory expectations and among different collision energies are provided. Also the new observation of $\\Upsilon(1S)\\Upsilon(1S)$ production is reported.
Lepton flavour violation searches at the LHC
Dawe, Edmund; The ATLAS collaboration
2015-01-01
Recent results from searches for lepton flavour violation performed by ATLAS and CMS in the $\\sqrt{s}=8~\\text{TeV}$ data are presented. The search for $Z\\rightarrow e\\mu$ and lepton flavour violating heavy neutral particle decays are summarized before covering the search for $H\\rightarrow \\mu \\tau$ in greater detail.
Production of Japanese Soy-Sauce Flavours
Sluis, van der C.
2001-01-01
The salt-tolerant yeasts Zygosaccharomyces rouxii and Candida versatilis are important for the formation of flavour in Japanese soy-sauce processes. In these processes Z. rouxii produces the flavour components ethanol, higher alcohols and 4-hydroxyfuranones, while C. versatilis is responsible for th
Mass Bounds for Flavour Mixing Bileptons
Tully, M B
1999-01-01
Mass bounds for doubly-charged bilepton gauge bosons are derived from constraints on fermion pair production at LEP and lepton-flavour violating charged lepton decays. The limit obtained of 700 GeV for the doubly-charged bilepton does not depend on the bilepton coupling being flavour-diagonal, unlike other bounds which have been given in the literature.
A{sub 4} family symmetry and quark-lepton unification
Energy Technology Data Exchange (ETDEWEB)
King, Stephen F. [School of Physics and Astronomy, University of Southampton, SO16 1BJ Southampton (United Kingdom)]. E-mail: sfk@hep.phys.soton.ac.uk; Malinsky, Michal [School of Physics and Astronomy, University of Southampton, SO16 1BJ Southampton (United Kingdom)]. E-mail: malinsky@phys.soton.ac.uk
2007-02-15
We present a model of quark and lepton masses and mixings based on A{sub 4} family symmetry, a discrete subgroup of an SO(3) flavour symmetry, together with Pati-Salam unification. It accommodates tri-bimaximal neutrino mixing via constrained sequential dominance with a particularly simple vacuum alignment mechanism emerging through the effective D-term contributions to the scalar potential.
Seiberg duality versus hidden local symmetry
Abel, Steven
2012-01-01
It is widely believed that the emergent magnetic gauge symmetry of SQCD is analogous to a hidden local symmetry (HLS). We explore this idea in detail, deriving the entire (spontaneously broken) magnetic theory by applying the HLS formalism to spontaneously broken SU(N) SQCD. We deduce the K\\"ahler potential in the HLS description, and show that gauge and flavour symmetry are smoothly restored along certain scaling directions in moduli space. We propose that it is these symmetry restoring directions, associated with the R-symmetry of the theory, that allow full Seiberg duality. Reconsidering the origin of the magnetic gauge bosons as the rho-mesons of the electric theory, colour-flavour locking allows a simple determination of the parameter "a". Its value continuously interpolates between a=2 on the baryonic branch of moduli space - corresponding to "vector meson dominance" - and a=1 on the mesonic branch. Both limiting values are consistent with previous results in the literature. The HLS formalism is further...
Flavour Physics and Implication for New Phenomena
Isidori, Gino
2016-10-01
Flavour physics represents one of the most interesting and, at the same time, less understood sector of the Standard Theory. On the one hand, the peculiar pattern of quark and lepton masses, and their mixing angles, may be the clue to some new dynamics occurring at high-energy scales. On the other hand, the strong suppression of flavour-changing neutral-current processes, predicted by the Standard Theory and confirmed by experiments, represents a serious challenge to extend the Theory. This article reviews both these aspects of flavour physics from a theoretical perspective.
Precision physics with heavy-flavoured hadrons
Koppenburg, Patrick
2015-01-01
The understanding of flavour dynamics is one of the key aims of elementary particle physics. The last 15 years have witnessed the triumph of the Kobayashi-Maskawa mechanism, which describes all flavour changing transitions of quarks in the Standard Model. This important milestone has been reached owing to a series of experiments, in particular to those operating at the so-called $B$ factories, at the Tevatron, and now at the LHC. We briefly review status and perspectives of flavour physics, highlighting the results where the LHC has given the most significant contributions, notably including the recent observation of the $B_s^0\\to\\mu^+\\mu^-$ decay.
Dynamics of Non-supersymmetric Flavours
Alam, M Sohaib; Kundu, Arnab; Kundu, Sandipan
2013-01-01
We continue investigating the effect of the back-reaction by non-supersymmetric probes in the Kuperstein-Sonnenschein model. In the limit when the back-reaction is small, we discuss physical properties of the back-reacted geometry. We further introduce additional probe flavours in this back-reacted geometry and study in detail the phase structure of this sector when a constant electromagnetic field or a chemical potential are present. We find that the Landau pole, which serves as the UV cut-off of the background geometry, also serves as an important scale in the corresponding thermodynamics of the additional flavour sector. We note that since this additional probe flavours are indistinguishable from the back-reacting flavours, the results we obtain point to a much richer phase structure of the system.
Heavy flavour hadron spectroscopy: An overview
Indian Academy of Sciences (India)
P C Vinodkumar
2014-11-01
A comprehensive overview and some of the theoretical attempts towards understanding heavy flavour hadron spectroscopy are presented. Apart from the conventional quark structure (quark, antiquarks structure for the mesons and three-quarks structure of baryons) of hadrons, multiquark hadrons the hadron molecular states etc., also will be reviewed. Various issues and challenges in understanding the physics and dynamics of the quarks at the hadronic dimensions are highlighted. Looking into the present and future experimental prospects at different heavy flavour laboratories like BES-III, CLEO-c, BaBar, Belle, LHC etc., the scope for theoretical extensions of the present knowledge of heavy flavour physics would be very demanding. In this context, many relevant contributions from the forthcoming PANDA Facility are expected. Scopes and outlook of the hadron physics at the heavy flavour sector in view of the future experimental facilities are highlighted.
New trends in beer flavour compound analysis.
Andrés-Iglesias, Cristina; Montero, Olimpio; Sancho, Daniel; Blanco, Carlos A
2015-06-01
As the beer market is steadily expanding, it is important for the brewing industry to offer consumers a product with the best organoleptic characteristics, flavour being one of the key characteristics of beer. New trends in instrumental methods of beer flavour analysis are described. In addition to successfully applied methods in beer analysis such as chromatography, spectroscopy, nuclear magnetic resonance, mass spectrometry or electronic nose and tongue techniques, among others, sample extraction and preparation such as derivatization or microextraction methods are also reviewed.
Flavour Violation in Anomaly Mediated Supersymmetry Breaking
Allanach, B. C.; Hiller, G; Jones, D. R. T.; Slavich, P.(LPTHE, UPMC Univ. Paris 06, Sorbonne Universités, 4 Place Jussieu, 75252, Paris, France)
2009-01-01
32 pages, 8 figures International audience We study squark flavour violation in the anomaly mediated supersymmetry broken (AMSB) minimal supersymmetric standard model. Analytical expressions for the three-generational squark mass matrices are derived. We show that the anomaly-induced soft breaking terms have a decreasing amount of squark flavour violation when running from the GUT to the weak scale. Taking into account inter-generational squark mixing, we work out non-trivial constraint...
b-flavour tagging in pp collisions
Birnkraut, Alex
2015-01-01
An essential ingredient of all time-dependent CP violation studies of B mesons is the ability to tag the initial flavour of the B meson. The harsh environment of 7 and 8 TeV pp collisions makes this a particularly difficult enterprise. We report progresses in the flavour tagging of B0 and Bs mesons, including developments of novel techniques like the use of an opposite side charm tagger.
The role of attention in flavour perception
Directory of Open Access Journals (Sweden)
Stevenson Richard J
2012-03-01
Full Text Available Abstract Flavour results primarily from the combination of three discrete senses: taste, somatosensation and olfaction. In contrast to this scientific description, most people seem unaware that olfaction is involved in flavour perception. They also appear poorer at detecting the olfactory components of a flavour relative to the taste and somatosensory parts. These and other findings suggest that flavour may in part be treated as a unitary experience. In this article, I examine the mechanisms that may contribute to this unification, in particular the role of attention. Drawing on recent work, the evidence suggests that concurrent gustatory and somatosensory stimulation capture attention at the expense of the olfactory channel. Not only does this make it hard to voluntarily attend to the olfactory channel, but it also can explain why olfaction goes largely unnoticed in our day-to-day experience of flavour. It also provides a useful framework for conceptualizing how the unitary experience of flavour may arise from three anatomically discrete sensory systems.
Checking Flavour Models at Neutrino Facilities
Meloni, Davide
2013-01-01
In the recent years, the industry of model building has been the subject of the intense activity, especially after the measurement of a relatively large values of the reactor angle. Special attention has been devoted to the use of non-abelian discrete symmetries, thanks to their ability of reproducing some of the relevant features of the neutrino mixing matrix. In this paper, we consider two special relations between the leptonic mixing angles, arising from models based on S4 and A4, and study whether, and to which extent, they can be distinguished at superbeam facilities, namely T2K, NOvA and T2HK.
Heavy Flavour production in ATLAS
International Nuclear Information System (INIS)
ATLAS prepared a program for measurements of production cross sections both of b-hadrons and Onia in central proton-proton collisions at new energy 14 TeV of LHC. Dedicated triggers based on muon, di-muon or electron signatures are designed to accommodate large statistics with already first several months. Starting from semi-inclusive measurements for very early stage exclusive channels will soon dominate measurements, allowing tests of QCD in Heavy Flavour sector already with 10 pb-1. With larger statistics production polarization measurements are being prepared for J/ψ and Λb. It is expected that 30 fb-1 collected at 1033cm-2 s-1 will allow specific measurements not accessible with limited statistics of Tevatron. In particular b polarization measurement can be achieved using Λb → J/ψ Λ decay. In J/ψ a polarization measurement will allow to confirm or exclude model predictions within large interval of transverse momenta. (author)
Heavy Flavour Electron Elliptic Flow
Gutierrez Ortiz, Nicolas Gilberto
Due to the large mass of the Charm and Beauty quarks, they are c reated in the very first moments of the ultra-high energy nucleus-nucleus collisions taking place at the CERN LHC, therefore, they should be unaware of the geome try of the colli- sion system and carry no azimuthal anisotropies. Similarly , the energy loss via gluon radiation for these massive quarks should be suppressed, th e so-called dead cone ef- fect. Although the observation of elliptic flow in the electro ns produced through the semileptonic decay of these heavy mesons is an indirect meas urement, throughout this thesis it will be shown that a strong correlation exists between the momentum anisotropy of the mother and daughter particles. In the low t ransverse momentum region such measurement would establish whether or not the s ystem reaches local thermal equilibrium. While at large transverse momentum, t he observation of collec- tivity for the heavy flavours can be understood only if the col lisional and radiative in-medium interaction...
Häring, Reto Andreas
1993-01-01
The representations of the observable algebra of a low dimensional quantum field theory form the objects of a braided tensor category. The search for gauge symmetry in the theory amounts to finding an algebra which has the same representation category. In this paper we try to establish that every quantum field theory satisfying some basic axioms posseses a weak quasi Hopf algebra as gauge symmetry. The first step is to construct a functor from the representation category to the category of finite dimensional vector spaces. Given such a functor we can use a generalized reconstruction theorem to find the symmetry algebra. It is shown how this symmetry algebra is used to build a gauge covariant field algebra and we investigate the question why this generality is necessary.
A Grand {Delta}(96) Multiplication-Sign SU(5) Flavour Model
Energy Technology Data Exchange (ETDEWEB)
King, Stephen F., E-mail: king@soton.ac.uk [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom); Luhn, Christoph, E-mail: christoph.luhn@durham.ac.uk [Institute for Particle Physics Phenomenology, University of Durham, Durham, DH1 3LE (United Kingdom); Stuart, Alexander J., E-mail: a.stuart@soton.ac.uk [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom)
2013-02-11
Recent results from the Daya Bay and RENO reactor experiments have measured the smallest lepton mixing angle and found it to have a value of {theta}{sub 13} Almost-Equal-To 9 Degree-Sign . This result presents a new challenge for the existing paradigms of discrete flavour symmetries which attempt to describe all quark and lepton masses and mixing angles. Here we propose a Supersymmetric Grand Unified Theory of Flavour based on {Delta}(96) Multiplication-Sign SU(5), together with a U(1) Multiplication-Sign Z{sub 3} symmetry, including a full discussion of {Delta}(96) in a convenient basis. The Grand {Delta}(96) Multiplication-Sign SU(5) Flavour Model relates the quark mixing angles and masses in the form of the Gatto-Sartori-Tonin relation and realises the Georgi-Jarlskog mass relations between the charged leptons and down-type quarks. We predict a Bi-trimaximal (not Tri-bimaximal) form of neutrino mixing matrix, which, after including charged lepton corrections with zero phase, leads to the following GUT scale predictions for the atmospheric, solar, and reactor mixing angles: {theta}{sub 23} Almost-Equal-To 36.9 Degree-Sign , {theta}{sub 12} Almost-Equal-To 32.7 Degree-Sign and {theta}{sub 13} Almost-Equal-To 9.6 Degree-Sign , in good agreement with recent global fits, and a zero Dirac CP phase {delta} Almost-Equal-To 0.
The supersymmetric flavour problem in 5D GUTs and its consequences for LHC phenomenology
Energy Technology Data Exchange (ETDEWEB)
Bruemmer, F. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Fichet, S.; Kraml, S. [CNRS/IN2P3, Grenoble (France). Lab. de Physique Subatomique et de Cosmologie
2011-09-15
We study supersymmetric models with a GUT-sized extra dimension, where both the Higgs fields and the SUSY breaking hidden sector are localized on a 4D brane. Exponential wave function profiles of the matter fields give rise to hierarchical structures in the Yukawa couplings and soft terms. Such structures can naturally explain hierarchical fermion masses and mixings, while at the same time alleviating the supersymmetric flavour problem. We discuss two sources of supersymmetry breaking, radion mediation and brane fields, and perform a detailed numerical analysis, thoroughly taking into account the proliferation of unknown O(1) coefficients that occurs in this class of models. It turns out that additional assumptions on supersymmetry breaking are necessary to evade the stringent experimental bounds on lepton flavour violation. The favourable regions of parameter space are then examined with regards to their LHC phenomenology. They generically feature heavy gluinos and squarks beyond current bounds. Lepton flavour violation in SUSY cascade decays can give interesting signatures. (orig.)
Spontaneous CP violation and Non-Abelian Family Symmetry in SUSY
Ross, Graham G; Vives, O; Ross, Graham G.; Velasco-Sevilla, Liliana; Vives, Oscar
2004-01-01
We analyse the properties of generic models based on an SU(3) family symmetry providing a full description of quark charged lepton and neutrino masses and mixing angles. We show that a precise fit of the resulting fermion textures is consistent with CP being spontaneously broken in the flavour sector. The CP violating phases are determined by the scalar potential and we discuss how symmetries readily lead to a maximal phase controlling CP violation in the quark sector. In a specific model the CP violation to be expected in the neutrino sector is related to that in the quark sector and we determine this relation for two viable models. In addition to giving rise to the observed structure of quark and lepton masses this class of model solves both the CP and flavour problems normally associated with supersymmetric models. The flavour structure of the soft supersymmetry breaking terms is controlled by the family symmetry and we analyse some of the related phenomenological implications.
2006-01-01
The 4th meeting of the 'Flavour in the era of the LHC' workshop will take place at CERN on 9-11 October, 2006. The goal of this workshop is to outline and document a programme for flavour physics for the next decade, addressing in particular the complementarity and synergy between the discoveries we expect to emerge from the LHC and the potential for accurate measurements of future flavour factories. Over 150 physicists will join in the discussions of the three working groups dedicated to 'Flavour physics at high Q', 'B/D/K decays' and 'Flavour in the lepton sector, EDM's, g-2, etc'. The previous meetings took place in November 2005, and in February and May this year. In addition to the working group sessions, a special miniworkshop dedicated to future prospects for electric dipole moment (EDM) searches and g-2 measurements will be held on 9-10 October. Sensitive EDM and g-2 experiments probe physics in an integral way, and in many cases their physics reach is much higher than the spectrometer searches at th...
2006-01-01
The 4th meeting of the 'Flavour in the era of the LHC'workshop will take place at CERN on 9-11 October, 2006. The goal of this workshop is to outline and document a programme for flavour physics for the next decade, addressing in particular the complementarity and synergy between the discoveries we expect to emerge from the LHC and the potential for accurate measurements of future flavour factories. Over 150 physicists will join in the discussions of the three working groups dedicated to 'Flavour physics at high Q', 'B/D/K decays'and 'Flavour in the lepton sector, EDM's, g-2, etc'. The previous meetings took place in November 2005, and in February and May this year. In addition to the working group sessions, a special miniworkshop dedicated to future prospects for electric dipole moment (EDM) searches and g-2 measurements will be held on 9-10 October. Sensitive EDM and g-2 experiments probe physics in an integral way, and in many cases their physics reach is much higher than the spectrometer searches at th...
Study of baryon number and lepton flavour violation in the new minimal supersymmetric SO(10)GUT
Kaur, Charanjit
2015-01-01
We study the so-called new minimal supersymmetric SO(10) GUT(NMSGUT) where explicit spontaneous symmetry breaking allows determination of superheavy spectrum and thus threshold corrections to the effective MSSM couplings. This provides a generic mechanism to resolve the long standing super fast proton decay in Susy GUTs. We estimate lepton flavor violation associated with realistic charged fermion and (Type I seesaw) neutrino fit and show compatibility with baryon number and lepton flavour violation limits. We improve NMSGUT fits by including important loop corrections to sparticle spectra. Our fits use 5 GUT compatible soft supersymmetry breaking parameters of the Supergravity with Non-Universal Higgs Masses(SUGRY-NUHM) type. We calculate the full two loop NMSGUT gauge-Yukawa beta functions to study feasibility of the NUHM parameters via strong renormalization of SO(10) Higgs soft masses. Focus on MSSM Higgs allows formulation of a "Yukawonification" strategy for gauged flavour unification.
Implications of lepton flavour violation on long baseline neutrino oscillation experiments
Soumya, C
2016-01-01
Non-standard neutrino interactions (NSIs), the sub-leading effects in the flavour transitions of neutrinos, play a crucial role in the determination of the various unknowns in neutrino oscillations, such as neutrino mass hierarchy, Dirac CP violating phase and the octant of atmospheric mixing angle. In view of the recent experimental observation of several lepton flavor universality (LFU) violating observables in $B$ decays, we study the possible implications of these interactions in the determination of various neutrino oscillation parameters. We consider the model with an additional $Z'$ boson (which is quite successful in explaining the observed LFU anomalies) and analyze its effect in the lepton flavour violating (LFV) $\\tau$ decays, i.e., $\\tau^- \\to e^- e^+ e^-$ and $\\tau^- \\to e^- \\pi^0$. From the present upper bounds of these decay rates, we obtain the constraints on the new physics parameters, which are related to the corresponding NSI parameters in the neutrino sector by $SU(2)_L$ symmetry. These ne...
New perspectives for heavy flavour physics from the lattice
Energy Technology Data Exchange (ETDEWEB)
Sommer, R. [John von Neumann-Institut fuer Computing NIC/DESY, Zeuthen (Germany)
2009-06-15
Heavy flavours represent a challenge for lattice QCD. We discuss it in very general terms. We give an idea of the significant recent progress which opens up good perspectives for high precision first principles QCD computations for flavour physics. (orig.)
Minimal flavour violation and SU(5)-unification
International Nuclear Information System (INIS)
Minimal flavour violation in its strong or weak versions, based on U(3)3 and U(2)3, respectively, allows suitable extensions of the standard model at the TeV scale to comply with current flavour constraints in the quark sector. Here we discuss considerations analogous to minimal flavour violation (MFV) in the context of SU(5)-unification, showing the new effects/constraints that arise both in the quark and in the lepton sector, where quantitative statements can be made controlled by the CKM matrix elements. The case of supersymmetry is examined in detail as a particularly motivated example. Third generation sleptons and neutralinos in the few hundred GeV range are shown to be compatible with current constraints. (orig.)
Flavour-Violating Gluino and Squark Decays
Energy Technology Data Exchange (ETDEWEB)
Hurth, Tobias; /CERN /SLAC; Porod, Werner; /Wurzburg U.
2010-06-11
We consider scenarios with large flavour violating entries in the squark mass matrices focusing on the mixing between second and third generation squarks. These entries govern both, flavour violating low energy observables on the one hand and squark and gluino decays on the other hand. We first discuss the constraints on the parameter space due to the recent data on B mesons from the B factories and Tevatron. We then consider flavour violating squark and gluino decays and show that they can still be typically of order 10% despite the stringent constraints from low energy data. Finally we briefly comment on the impact for searches and parameter determinations at future collider experiments such as the upcoming LHC or a future International Linear Collider.
Minimal flavour violation and SU(5)-unification
Energy Technology Data Exchange (ETDEWEB)
Barbieri, Riccardo, E-mail: barbieri@sns.it; Senia, Fabrizio, E-mail: fabrizio.senia@sns.it [Scuola Normale Superiore and INFN, Piazza dei Cavalieri 7, 56126, Pisa (Italy)
2015-12-17
Minimal flavour violation in its strong or weak versions, based on U(3){sup 3} and U(2){sup 3}, respectively, allows suitable extensions of the standard model at the TeV scale to comply with current flavour constraints in the quark sector. Here we discuss considerations analogous to minimal flavour violation (MFV) in the context of SU(5)-unification, showing the new effects/constraints that arise both in the quark and in the lepton sector, where quantitative statements can be made controlled by the CKM matrix elements. The case of supersymmetry is examined in detail as a particularly motivated example. Third generation sleptons and neutralinos in the few hundred GeV range are shown to be compatible with current constraints.
The custodially protected Randall-Sundrum model. Theoretical aspects and flavour phenomenology
Energy Technology Data Exchange (ETDEWEB)
Blanke, Monika
2009-07-24
Models with a warped extra dimension, so-called Randall-Sundrum models, provide an appealing solution to the gauge and flavour hierarchy problems of the Standard Model. After introducing the theoretical basics of such models, we concentrate on a specific model whose symmetry structure is extended to protect the T parameter and the Zb{sub L} anti b{sub L} coupling from large corrections. We introduce the basic action and discuss in detail effects of electroweak symmetry breaking and the flavour structure of the model. Then we analyse meson-antimeson mixing and rare decays that are affected by new tree level contributions from the Kaluza-Klein modes of the gauge bosons and from the Z boson in an important manner. After deriving analytic expressions for the most important K and B physics observables, we perform a global numerical analysis of the new effects in the model in question. We confirm the recent findings that a stringent constraint on the model is placed by CP-violation in K{sup 0} - anti K{sup 0} mixing. However, even for Kaluza-Klein particles in the reach of the LHC an agreement with all available data can be obtained without significant fine-tuning. We find possible large effects in either CP-violating effects in the B{sub s} - anti B{sub s} system or in the rare K decays, but not simultaneously. In any case the deviations from the Standard Model predictions in the rare B decays are small and difficult to measure. The specific pattern of new flavour effects allows to distinguish this model from other New Physics frameworks, which we demonstrate explicitly for the case of models with Minimal Flavour Violation and for the Littlest Higgs model with T-parity. (orig.)
Zuelicke, U
2012-01-01
The most fundamental characteristics of a physical system can often be deduced from its behaviour under discrete symmetry transformations such as time reversal, parity and chirality. Here we review basic symmetry properties of the relativistic quantum theories for free electrons in (2+1)- and (1+1)-dimensional spacetime. Additional flavour degrees of freedom are necessary to properly define symmetry operations in (2+1) dimensions and are generally present in physical realisations of such systems, e.g., in single sheets of graphite. We find that there exist two possibilities for defining any flavour-coupling discrete symmetry operation of the two-flavour (2+1)-dimensional Dirac theory. Physical implications of this duplicity are discussed.
LHCb New algorithms for Flavour Tagging at the LHCb experiment
Fazzini, Davide
2016-01-01
The Flavour Tagging technique allows to identify the B initial flavour, required in the measurements of flavour oscillations and time-dependent CP asymmetries in neutral B meson systems. The identification performances at LHCb are further enhanced thanks to the contribution of new algorithms.
Heavy Flavour Production and Decay at ATLAS
Jones, RWL; The ATLAS collaboration
2013-01-01
ATLAS is taking advantage of its large integrated luminosity band sophisticated muon and dimuon triggers to make competitive measurements of heavy flavour production and decay. Inclusive production and heavy flavour jet production is discussed before turning to charm and onium production. The production and decay of individual B hadron species is then addressed, including the current best measurement of the Λb lifetime. A much improved analysis of CP related quantities in Bs decays is presented, before turning to recent results and prospects for rare B decays.
SU(3) flavour breaking and baryon structure
Energy Technology Data Exchange (ETDEWEB)
Cooke, A.N.; Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Kobe, Hyogo (Japan); Pleiter, D. [Forschungszentrum Juelich GmbH (Germany). Juelich Supercomputing Centre (JSC); Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Div.; Shanahan, P.; Zanotti, J.M. [Adelaide Univ., SA (Australia). CSSM, School of Chemistry and Physics; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Stueben, H. [Hamburg Univ. (Germany). Regionales Rechenzentrum; Collaboration: QCDSF/UKQCD Collaboration
2013-11-15
We present results from the QCDSF/UKQCD collaboration for hyperon electromagnetic form factors and axial charges obtained from simulations using N{sub f}=2+1 flavours of O(a)-improved Wilson fermions. We also consider matrix elements relevant for hyperon semileptonic decays. We find flavour-breaking effects in hyperon magnetic moments which are consistent with experiment, while our results for the connected quark spin content indicates that quarks contribute more to the spin of the {Xi} baryon than they do to the proton.
Attanucci, Frank J.; Losse, John
2008-01-01
In a first calculus course, it is not unusual for students to encounter the theorems which state: If f is an even (odd) differentiable function, then its derivative is odd (even). In our paper, we prove some theorems which show how the symmetry of a continuous function f with respect to (i) the vertical line: x = a or (ii) with respect to the…
Higgs-mediated FCNCs: Natural Flavour Conservation vs. Minimal Flavour Violation
Buras, Andrzej J; Gori, Stefania; Isidori, Gino
2010-01-01
We compare the effectiveness of two hypotheses, Natural Flavour Conservation (NFC) and Minimal Flavour Violation (MFV), in suppressing the strength of flavour-changing neutral-currents (FCNCs) in models with more than one Higgs doublet. We show that the MFV hypothesis, in its general formulation, is more stable in suppressing FCNCs than the hypothesis of NFC alone when quantum corrections are taken into account. The phenomenological implications of the two scenarios are discussed analysing meson-antimeson mixing observables and the rare decays B -> mu+ mu-. We demonstrate that, introducing flavour-blind CP phases, two-Higgs doublet models respecting the MFV hypothesis can accommodate a large CP-violating phase in Bs mixing, as hinted by CDF and D0 data and, without extra free parameters, soften significantly in a correlated manner the observed anomaly in the relation between epsilon_K and S_psi_K.
SUGRA New Inflation with Heisenberg Symmetry
Antusch, Stefan
2013-01-01
We propose a realisation of 'new inflation' in supergravity (SUGRA), where the flatness of the inflaton potential is protected by a Heisenberg symmetry. Inflation can be associated with a particle physics phase transition, with the inflaton being a (D-flat) direction of Higgs fields which break some symmetry at high energies, e.g. of GUT Higgs fields or of Higgs fields for flavour symmetry breaking. This is possible since compared to a shift symmetry, which is usually used to protect a flat inflaton potential, the Heisenberg symmetry is compatible with a (gauge) non-singlet inflaton field. In contrast to conventional new inflation models in SUGRA, where the predictions depend on unknown parameters of the K"ahler potential, the model with Heisenberg symmetry makes discrete predictions for the primordial perturbation parameters which depend only on the order n at which the inflaton appears in the effective superpotential. The predictions for the spectral index n_s can be close to the best-fit value of the lates...
General squark flavour mixing: constraints, phenomenology and benchmarks
De Causmaecker, Karen; Herrmann, Bjoern; Mahmoudi, Farvah; O'Leary, Ben; Porod, Werner; Sekmen, Sezen; Strobbe, Nadja
2015-01-01
We present an extensive study of non-minimal flavour violation in the squark sector in the framework of the Minimal Supersymmetric Standard Model. We investigate the effects of multiple non-vanishing flavour-violating elements in the squark mass matrices by means of a Markov Chain Monte Carlo scanning technique and identify parameter combinations that are favoured by both current data and theoretical constraints. We then detail the resulting distributions of the flavour-conserving and flavour-violating model parameters. Based on this analysis, we propose a set of benchmark scenarios relevant for future studies of non-minimal flavour violation in the Minimal Supersymmetric Standard Model.
Safety evaluation of natural flavour complexes
Smith, R.L.; Adams, T.B.; Cohen, S.M.; Doull, J.; Feron, V.J.; Goodman, J.I.; Hall, R.L.; Marnett, L.J.; Portoghese, P.S.; Waddell, W.J.; Wagner, B.M.
2004-01-01
Natural flavour complexes (NFCs) are chemical mixtures obtained by applying physical separation methods to botanical sources. Many NFCs are derived from foods. In the present paper, a 12-step procedure for the safety evaluation of NFCs, 'the naturals paradigm', is discussed. This procedure, which is
Heavy flavour physics at the LHC
International Nuclear Information System (INIS)
A summary of results in heavy flavour physics from Run 1 of the LHC is presented. Topics discussed include spectroscopy, mixing, CP violation and rare decays of charmed and beauty hadrons. The results are consistent with Standard Model predictions, although several puzzles and hints of discrepancies demand further investigation with larger data samples
Sweetness flavour interactions in soft drinks.
Nahon, D.F.; Roozen, J.P.; Graaf, de C.
1996-01-01
Sucrose can be substituted by intense sweeteners to lower the calorie content of soft drinks. Although the sweetness is kept at the same level as much as possible, the flavour of the product often changes. This change could be due to both the mechanism of sensory perception and interactive effects o
Working group report: Collider and flavour physics
Indian Academy of Sciences (India)
Debajyoti Choudhury; Asesh K Datta; Anirban Kundu
2009-01-01
The activities of the working group took place under two broad subgroups: Collider Physics subgroup and Flavour Physics subgroup. Reports on some of the projects undertaken are included. Also, some of the leading discussions organized by the working group are summarized.
The Revival of Kaon Flavour Physics
Buras, Andrzej J
2016-01-01
After years of silence we should witness in the rest of this decade and in the next decade the revival of kaon flavour physics. This is not only because of the crucial measurements of the branching ratios for the rare decays $K^+\\to\\pi^+\
Search for new flavour production at PETRA
International Nuclear Information System (INIS)
The topological distribution of hadrons from the reaction e+e- → multihadrons has been studied at PETRA energies between √ s = 22 and 31.6 GeV. No evidence is seen for spherical events which would be expected if massive particles bearing new flavours were produced. (orig.)
Minimal flavour violation and beyond: Towards a flavour code for short distance dynamics
Buras, Andrzej J
2010-01-01
This decade should provide the first definitive signals of New Physics (NP) beyond the Standard Model (SM) and the goal of these lectures is a review of flavour physics in various extensions of the SM that have been popular in the last ten years. After an overture, two pilot sections and a brief summary of the structure of flavour violation and CP violation in the SM, we will present the theoretical framework for weak decays that will allow us to distinguish between different NP scenarios. Subsequently we will present twelve concrete BSM models summarizing the patterns of flavour violation characteristic for each model. In addition to models with minimal flavour violation (MFV) accompanied by flavour blind phases we will discuss a number of extensions containing non-MFV sources of flavour and CP violation and, in particular, new local operators originating in right-handed charged currents and scalar currents. Next we will address various anomalies in the data as seen from the point of view of the SM that appe...
Cern Academic Training programme 2011 - Flavour Physics and CP Violation
PH Department
2011-01-01
LECTURE SERIES 4, 5, 6 and 7 April 2011 Flavour Physics and CP Violation Dr. Yosef Nir (Weizmann Institute of Science, Rehovot, Israel 11:00-12:00 - 4, 6 and 7 April - Bldg. 222-R-001 - Filtration Plant 5 April - Bldg. 80-1-001 - Globe 1st Floor The B-factories have led to significant progress in our understanding of CP violation and of flavour physics. Yet, two flavour puzzles remain. The standard model flavour puzzle is the question of why there is smallness and hierarchy in the flavour parameters. The new physics flavour puzzle is the question of why TeV-scale new physics was not signalled in flavour changing neutral current processes. The high pT experiments, ATLAS and CMS, are likely to shed light on these puzzles. As concerns CP violation, the LHC will lead to progress on the puzzle of the baryon asymmetry as well.
Symmetry, Symmetry Breaking and Topology
Directory of Open Access Journals (Sweden)
Siddhartha Sen
2010-07-01
Full Text Available The ground state of a system with symmetry can be described by a group G. This symmetry group G can be discrete or continuous. Thus for a crystal G is a finite group while for the vacuum state of a grand unified theory G is a continuous Lie group. The ground state symmetry described by G can change spontaneously from G to one of its subgroups H as the external parameters of the system are modified. Such a macroscopic change of the ground state symmetry of a system from G to H correspond to a “phase transition”. Such phase transitions have been extensively studied within a framework due to Landau. A vast range of systems can be described using Landau’s approach, however there are also systems where the framework does not work. Recently there has been growing interest in looking at such non-Landau type of phase transitions. For instance there are several “quantum phase transitions” that are not of the Landau type. In this short review we first describe a refined version of Landau’s approach in which topological ideas are used together with group theory. The combined use of group theory and topological arguments allows us to determine selection rule which forbid transitions from G to certain of its subgroups. We end by making a few brief remarks about non-Landau type of phase transition.
LIE SYMMETRIES AND NOETHER SYMMETRIES
Directory of Open Access Journals (Sweden)
PGL Leach
2012-10-01
Full Text Available We demonstrate that so-called nonnoetherian symmetries with which a known first integral is associated of a differential equation derived from a Lagrangian are in fact noetherian. The source of the misunderstanding lies in the nonuniqueness of the Lagrangian.
Neutrinos and Lepton Flavour Violation in the Left-Right Twin Higgs Model
Abada, Asmaa
2007-01-01
We analyse the lepton sector of the Left-Right Twin Higgs Model. This model offers an alternative way to solve the "little hierarchy" problem of the Standard Model. We show that one can achieve an effective see-saw to explain the origin of neutrino masses and that this model can accommodate the observed neutrino masses and mixings. We have also studied the lepton flavour violation process l_1 -> l_2 \\gamma and discussed how the experimental bound from these branching ratios constrains the scale of symmetry breaking of this Twin Higgs model.
International Nuclear Information System (INIS)
The sky uniformity can be noticed in studying the repartition of objects far enough. The sky isotropy description uses space rotations. The group theory elements will allow to give a meaning at the same time precise and general to the word a ''symmetry''. Universe models are reviewed, which must have both of the following qualities: - conformity with the physic known laws; - rigorous symmetry following one of the permitted groups. Each of the models foresees that universe evolution obeys an evolution equation. Expansion and big-bang theory are recalled. Is universe an open or closed space. Universe is also electrically neutral. That leads to a work hypothesis: the existing matter is not given data of universe but it appeared by evolution from nothing. Problem of matter and antimatter is then raised up together with its place in universe
Anatomy of flavour-changing Z couplings in models with partial compositeness
Straub, David M
2013-01-01
In models with partially composite quarks, the couplings of quarks to the Z boson generically receive non-universal corrections that are not only constrained by electroweak precision tests but also lead to flavour-changing neutral currents at tree level. The impact of these flavour-changing couplings on rare K and B decays is studied in two-site models for three scenarios: an anarchic strong sector with two different choices of fermion representations both leading to a custodial protection of the Z->bb coupling, and for a strong sector invariant under a U(2)^3 flavour symmetry. In the complete numerical analysis, all relevant constraints from Delta(F)=2 processes are taken into account. In all scenarios, visible effects in rare K and B decays like K->pi nu anti-nu, B(s)->mu+mu- and B->K*mu+mu- are possible that can be scrutinized experimentally in the near future. Characteristic correlations between observables allow to distinguish the different cases. To sample the large parameter space of the anarchic model...
Relic neutrino decoupling including flavour oscillations
Energy Technology Data Exchange (ETDEWEB)
Mangano, Gianpiero [Dipartimento di Scienze Fisiche, Universita di Napoli Federico II and INFN, Sezione di Napoli, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Naples (Italy); Department of Physics, Syracuse University, Syracuse, NY 13244-1130 (United States); Miele, Gennaro [Dipartimento di Scienze Fisiche, Universita di Napoli Federico II and INFN, Sezione di Napoli, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Naples (Italy); Pastor, Sergio [Instituto de Fisica Corpuscular (CSIC-Universitat de Valencia), Ed. Institutos de Investigacion, Apdo. 22085, E-46071 Valencia (Spain)]. E-mail: pastor@ific.uv.es; Pinto, Teguayco [Instituto de Fisica Corpuscular (CSIC-Universitat de Valencia), Ed. Institutos de Investigacion, Apdo. 22085, E-46071 Valencia (Spain); Pisanti, Ofelia [Dipartimento di Scienze Fisiche, Universita di Napoli Federico II and INFN, Sezione di Napoli, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Naples (Italy); Serpico, Pasquale D. [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, D-80805 Munich (Germany)
2005-11-21
In the early universe, neutrinos are slightly coupled when electron-positron pairs annihilate transferring their entropy to photons. This process originates non-thermal distortions on the neutrino spectra which depend on neutrino flavour, larger for {nu}{sub e} than for {nu}{sub {mu}} or {nu}{sub {tau}}. We study the effect of three-neutrino flavour oscillations on the process of neutrino decoupling by solving the momentum-dependent kinetic equations for the neutrino spectra. We find that oscillations do not essentially modify the total change in the neutrino energy density, giving N{sub eff}=3.046 in terms of the effective number of neutrinos, while the small effect over the production of primordial {sup 4}He is increased by O(20%), up to 2.1x10{sup -4}. These results are stable within the presently favoured region of neutrino mixing parameters.
Neutrino observables from predictive flavour patterns
Energy Technology Data Exchange (ETDEWEB)
Cebola, Luis M.; Emmanuel-Costa, David [Universidade de Lisboa, Departamento de Fisica and Centro de Fisica Teorica de Particulas - CFTP, Instituto Superior Tecnico, Lisboa (Portugal); Felipe, Ricardo Gonzalez [Universidade de Lisboa, Departamento de Fisica and Centro de Fisica Teorica de Particulas - CFTP, Instituto Superior Tecnico, Lisboa (Portugal); ISEL - Instituto Superior de Engenharia de Lisboa, Instituto Politecnico de Lisboa, Lisboa (Portugal)
2016-03-15
We look for predictive flavour patterns of the effective Majorana neutrino mass matrix that are compatible with current neutrino oscillation data. Our search is based on the assumption that the neutrino mass matrix contains equal elements and a minimal number of parameters, in the flavour basis where the charged lepton mass matrix is diagonal and real. Three unique patterns that can successfully explain neutrino observables at the 3σ confidence level with just three physical parameters are presented. Neutrino textures described by four and five parameters are also studied. The predictions for the lightest neutrino mass, the effective mass parameter in neutrinoless double beta decays and for the CP-violating phases in the leptonic mixing are given. (orig.)
Neutrino observables from predictive flavour patterns
Cebola, Luis M; Felipe, Ricardo Gonzalez
2016-01-01
We look for predictive flavour patterns of the effective Majorana neutrino mass matrix that are compatible with current neutrino oscillation data. Our search is based on the assumption that the neutrino mass matrix contains equal elements and a minimal number of parameters, in the flavour basis where the charged lepton mass matrix is diagonal and real. Three unique patterns that can successfully explain neutrino observables at the $3\\sigma$ confidence level with just three physical parameters are presented. Neutrino textures described by four and five parameters are also studied. The predictions for the lightest neutrino mass, the effective mass parameter in neutrinoless double beta decays and the CP-violating phases in the leptonic mixing are given.
Some theoretical issues in heavy flavour physics
Indian Academy of Sciences (India)
Amol Dighe
2012-11-01
Some of the recent developments in heavy flavour physics will be reviewed. This will include an update on some of the Standard Model predictions, and a summary of recent measurements that may indicate the presence of new physics (NP). The focus will be on selected models of NP that are indicated by the anomalies in the current data. Observables that can potentially yield signatures of specific physics beyond the Standard Model will be pointed out.
Flavour democracy calls for the fourth generation
International Nuclear Information System (INIS)
It is argued with the help of an illustrative mode, that the inter species hierarchy among the fermion masses and the quark mixing angles can be accommodated naturally in the standard model with (approximate) flavour democracy provided there are four families of sequential quark-leptons with all members of the fourth family having roughly equal masses. The special problem of light neutrino masses (if any) and possible solutions are also discussed. (author). 15 refs
Flavour of fundamental particles and prime numbers
International Nuclear Information System (INIS)
The discreteness and continuity as described by the ratio of the discreteness of the n's and the continuous spread of n/2n, which is directly connected with the width and lifetimes of fundamental particles, the flavours of fundamental particles can be directly obtained. The behaviour of beta decay and the energy levels of light nuclei can also be predicted. The appearance of primes also seems to suggest that further application of reductionism to fundamental particles is not possible
Lepton flavour violation in the RS model
Energy Technology Data Exchange (ETDEWEB)
Moch, Paul; Beneke, Martin [Physik Department T31, Technische Universitaet Muenchen, 85748 Garching (Germany); Rohrwild, Juergen [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom)
2015-07-01
We consider charged lepton flavour observables in the Randall-Sundrum (RS) model with and without custodial protection.To this end, we apply a fully five dimensional (5D) framework to calculate the matching coefficients of the effective field theory at the electroweak scale. This enables us to compute predictions for the radiative decay μ → eγ as well as the decay μ → 3e and μ → e conversion in nuclei.
Including heavy flavour production in PDF fits
A.M. Cooper-Sarkar
2007-01-01
AT HERA heavy quarks may contribute up to 30% of the structure function $F_2$. The introduction of heavy quarks requires an extension of the DGLAP formalism. The effect of using different heavy flavour number schemes, and different approaches to the running of $\\alpha_s$, are compared using the ZEUS PDF fit formalism. The potential of including charm data in the fit is explored, using $D^*$ double differential cross-sections rather than the inclusive quantity $F_2^{c\\bar{c}}$.
Flavoured Large N Gauge Theory on a Compact Space with an External Magnetic Field
Filev, Veselin G
2012-01-01
The phase structure of flavoured N=2 SYM on a three sphere in an external magnetic field is studied. The binding effect the magnetic field competes with the dissociating effect of the Casimir free energy, leading to an interesting phase structure of confined and deconfined phases separated by a critical curve of a first order quantum phase transition. At vanishing magnetic field the phase transition is of a third order. For sufficiently strong magnetic field, the only stable phase is the confined phase and magnetic catalysis of chiral symmetry breaking is realized. The meson spectra of the theory exhibit Zeeman splitting and level crossing and feature a finite jump at the phase transition between the confined and deconfined phases. At strong magnetic field the ground state has a massless mode corresponding to the Goldstone boson associated with the spontaneously broken U(1) R-symmetry analogous to the eta' meson in QCD.
Peters, Kirstin
2010-01-01
A well-known result by Palamidessi tells us that {\\pi}mix (the {\\pi}-calculus with mixed choice) is more expressive than {\\pi}sep (its subset with only separate choice). The proof of this result argues with their different expressive power concerning leader election in symmetric networks. Later on, Gorla of- fered an arguably simpler proof that, instead of leader election in symmetric networks, employed the reducibility of "incestual" processes (mixed choices that include both enabled senders and receivers for the same channel) when running two copies in parallel. In both proofs, the role of breaking (ini- tial) symmetries is more or less apparent. In this paper, we shed more light on this role by re-proving the above result-based on a proper formalization of what it means to break symmetries-without referring to another layer of the distinguishing problem domain of leader election. Both Palamidessi and Gorla rephrased their results by stating that there is no uniform and reason- able encoding from {\\pi}mix i...
Ecker, G
1999-01-01
Broken chiral symmetry has become the basis for a unified treatment of hadronic interactions at low energies. After reviewing mechanisms for spontaneous chiral symmetry breaking, I outline the construction of the low--energy effective field theory of the Standard Model called chiral perturbation theory. The loop expansion and the renormalization procedure for this nonrenormalizable quantum field theory are developed. Evidence for the standard scenario with a large quark condensate is presented, in particular from high--statistics lattice calculations of the meson mass spectrum. Elastic pion--pion scattering is discussed as an example of a complete calculation to O(p^6) in the low--energy expansion. The meson--baryon system is the subject of the last lecture. After a short summary of heavy baryon chiral perturbation theory, a recent analysis of pion--nucleon scattering to O(p^3) is reviewed. Finally, I describe some very recent progress in the chiral approach to the nucleon--nucleon interaction.
Neutrino-Flavoured Sneutrino Dark Matter
March-Russell, John; McCullough, Matthew
2010-01-01
A simple theory of supersymmetric dark matter (DM) naturally linked to neutrino flavour physics is studied. The DM sector comprises a spectrum of mixed lhd-rhd sneutrino states where both the sneutrino flavour structure and mass splittings are determined by the associated neutrino masses and mixings. Prospects for indirect detection from solar capture are good due to a large sneutrino-nucleon cross-section afforded by the inelastic splitting (solar capture limits exclude an explanation of DAMA/LIBRA). We find parameter regions where all heavier states will have decayed, leaving only one flavour mixture of sneutrino as the candidate DM. Such regions have a unique `smoking gun' signature--sneutrino annihilation in the Sun produces a pair of neutrino mass eigenstates free from vacuum oscillations, with the potential for detection at neutrino telescopes through the observation of a hard spectrum of nu_mu and nu_tau (for a normal neutrino hierarchy). Next generation direct detection experiments can explore much of...
Neutrino-flavoured sneutrino dark matter
March-Russell, John; McCabe, Christopher; McCullough, Matthew
2010-03-01
A simple theory of supersymmetric dark matter (DM) naturally linked to neutrino flavour physics is studied. The DM sector comprises a spectrum of mixed lhd-rhd sneutrino states where both the sneutrino flavour structure and mass splittings are determined by the associated neutrino masses and mixings. Prospects for indirect detection from solar capture are good due to a large sneutrino-nucleon cross-section afforded by the inelastic splitting (solar capture limits exclude an explanation of DAMA/LIBRA). We find parameter regions where all heavier states will have decayed, leaving only one flavour mixture of sneutrino as the candidate DM. Such regions have a unique ‘smoking gun’ signature — sneutrino annihilation in the Sun produces a pair of neutrino mass eigenstates free from vacuum oscillations, with the potential for detection at neutrino telescopes through the observation of a hard spectrum of ν μ and ν τ (for a normal neutrino hierarchy). Next generation direct detection experiments can explore much of the parameter space through both elastic and inelastic scattering. We show in detail that the observed neutrino masses and mixings can arise as a consequence of supersymmetry breaking effects in the sneutrino DM sector, consistent with all experimental constraints.
Bimaximal neutrino mixing and weak complementarity with S4 discrete symmetry
Merlo, Luca
2009-01-01
The neutrino oscillation data are well explained by the tri-bimaximal pattern. Recently a paper appeared showing that also the bimaximal pattern could be a very good starting point in order to describe the lepton mixing. In this paper I review both the flavour structures and then I present an explicit model based on the discrete symmetry group S4.
Flavour Condensate and the Dark Sector of the Universe
Tarantino, Walter
2012-01-01
This thesis is devoted to the development of a nonperturbative quantum field theoretical approach to flavour physics, with special attention to cosmological applications. Neutrino flavour oscillation is nowadays a fairly well-established experimental fact. However, the formulation of flavour oscillations in a relativistic field theoretical framework presents non-trivial difficulties. A nonperturbative approach for building flavour states has been proposed by Blasone, Vitiello and coworkers. The formalism implies a non-trivial physical vacuum (called "flavour vacuum"), which might act as a source of Dark Energy. Furthermore, such a vacuum has been recognized as the effective vacuum state arising in the low energy limit of a string theoretical model, D-particle Foam Model. In the attempt of probing the observable phenomenology of the D-particle foam model, a simple toy model (two scalars with mixing \\`a la Blasone & Vitiello on a adiabatically expanding background) has been studied, proving that the flavour...
Effects of flavour absorption on foods and their packaging materials
Willige, van, R.W.G.
2002-01-01
Keywords: flavour absorption, scalping, packaging, food matrix, lldpe, ldpe, pp, pc, pet, pen,b-lactoglobulin, casein, pectin, cmc, lactose, saccharose, oil, modelling, storage, oxygen permeability, taste perception, sensory quality.Absorption of flavour compounds by linear low-density polyethylene (LLDPE) was studied in model systems representing differences in composition of the food matrix. Proteins,b-lactoglobuline and casein, were able to bind flavours, resulting in suppression of absorp...
Flavour tagging of $b$ mesons in $pp$ collisions at LHCb
Mueller, Vanessa
2016-01-01
Flavour tagging, i.e. the inference of the production flavour of reconstructed $b$ hadrons, is essential for precision measurements of decay time-dependent $CP$ violation and of mixing parameters in the the neutral $B$ meson systems. LHC's $pp$ collisions with their high track multiplicities constitute a challenging environment for flavour tagging and demand for new and improved strategies. We present recent progress and new developments in flavour tagging at the LHCb experiment, which will allow for a further improvement of $CP$ violation measurements in decays of $B^0$ and $B_s^0$ mesons.
Leptonic minimal flavour violation in warped extra dimensions
Indian Academy of Sciences (India)
Abhishek M Iyer; Sudhir K Vempati
2012-10-01
Lepton mass hierarchies and lepton flavour violation are revisited in the framework of Randall–Sundrum models. Models with Dirac-type as well as Majorana-type neutrinos are considered. The five-dimensional -parameters are fit to the charged lepton and neutrino masses and mixings using 2 minimization. Leptonic flavour violation is shown to be large in these cases. Schemes of minimal flavour violation are considered for the cases of an effective LLHH operator and Dirac neutrinos and are shown to significantly reduce the limits from lepton flavour violation.
A supersymmetric grand unified theory of flavour with PSL{sub 2}(7)xSO(10)
Energy Technology Data Exchange (ETDEWEB)
King, Stephen F., E-mail: king@soton.ac.u [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom); Luhn, Christoph, E-mail: christoph.luhn@soton.ac.u [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom)
2010-06-11
We construct a realistic Supersymmetric Grand Unified Theory of Flavour based on PSL{sub 2}(7)xSO(10), where the quarks and leptons in the 16 of SO(10) are assigned to the complex triplet representation of PSL{sub 2}(7), while the flavons are assigned to a combination of sextets and anti-triplets of PSL{sub 2}(7). Using a D-term vacuum alignment mechanism, we require the flavon sextets of PSL{sub 2}(7) to be aligned along the 3-3 direction leading to the third family Yukawa couplings, while the flavon anti-triplets describe the remaining Yukawa couplings. Other sextets are aligned along the neutrino flavour symmetry preserving directions leading to tri-bimaximal neutrino mixing via a type II see-saw mechanism, with predictions for neutrinoless double beta decay and cosmology.
CP and other Symmetries of Symmetries
Trautner, Andreas
2016-01-01
Outer automorphisms of symmetries ("symmetries of symmetries") in relativistic quantum field theories are studied, including charge conjugation (C), space-reflection (P) , and time-reversal (T) transformations. The group theory of outer automorphisms is pedagogically introduced and it is shown that CP transformations are special outer automorphisms of the global, local, and space-time symmetries of a theory. It is shown that certain discrete groups allow for a group theoretical prediction of parameter independent CP violating complex phases with fixed geometrical values. The remainder of this thesis pioneers the study of outer automorphisms which are not related to C, P, or T. It is shown how outer automorphisms, in general, relate symmetry invariants and, in theories with spontaneous symmetry breaking, imply relations between different vacuum expectation values. Thereby, outer automorphisms can give rise to emergent symmetries. An example model with a discrete symmetry and three copies of the Standard Model ...
Flavouring compounds in Indian potato snacks.
Raigond, Pinky; Singh, Brajesh; Dhulia, Akshita; Chopra, Shelly; Dutt, Som
2015-12-01
Market for processed potato products is rising day by day. Flavour plays important role in decision making by consumers due to their preferences for better tasting food. In potato and potato products, glutamic acid, aspartic acid, guanosine 5'-monophosphate (GMP) and adenosine 5'-monophosphate (AMP) are the major umami compounds which contribute towards flavour. Therefore, umami 5' nucleotides (AMP+GMP) were estimated from local potato products available as common fried products in the Indian markets and processed potato products being sold by the retailers. The analysis was also carried in raw, microwaved and pressure cooked tubers of forty seven Indian potato cultivars. Umami 5' nucleotide content ranged from 2.63 (Aloo seekh) to 8.26 μg/g FW (fried lachcha) in local potato products. In processed potato products, the content ranged from 2.72 μg/g FW (Smiles) to 14.75 μg/g FW (Aloo Bhujia). Along with aloo bhujia, umami 5' nucleotides were also high in dehydrated aloo lachcha (11.14 μg/g FW) and dehydrated potato chips (10.13 μg/g FW) and low in Smiles (2.72 μg/g FW) and Potato Shortz (3.40 μg/g FW). The study suggests that the potato products prepared solely from potato contained higher levels of umami 5' nucleotides compared to other products prepared by mixing potato with other cereals and vegetables. In Indian potato cultivars overall there was 14 % increase on microwave cooking and 31 % increase in flavouring compounds on pressure cooking. This type of study enabled in identifying better tasting cultivars for further product development and also to develop products with less addition of salt. PMID:26604408
Exclusive search for supersymmetry with same-flavour di-lepton final states with the ATLAS detector
Energy Technology Data Exchange (ETDEWEB)
Boehler, Michael
2012-06-15
Supersymmetry (SUSY) is one of the most promising extensions of the Standard Model of particle physics. It introduces a new symmetry between fermions and bosons by adding a bosonic superpartner to each SM fermion and a fermionic one to a each SM boson. If an excess of SUSY like signal is observed, SUSY particle properties (e.g. masses or mass differences) must be measured in order to determine the underlying SUSY parameters. Therefore, exclusive SUSY decay cascades with two leptons in the final state are isolated by the flavour subtraction method, in order to fit the endpoint of the invariant mass distribution of these leptons and determine SUSY particle mass differences. This analysis uses a data sample collected during the first half of 2011, corresponding to an integrated luminosity of 1 fb{sup -1} of {radical}(s)=7 TeV proton-proton collisions recorded with the ATLAS detector at the Large Hadron Collider. Since no significant same flavour excess is observed, the variable S, which is the measure of a same-flavour excess, is used to determine model-independent and model-dependent limits for different SUSY scenarios. The tightest limits can be set for models expecting exactly two opposite-sign same-flavour leptons and missing transverse momentum larger than 250 GeV. Assuming no combinatorial SUSY background events from different decay chains (ll'), models with di-lepton decays (ll) with SUSY same-flavour excess S{sub s} {>=}4.5 can be excluded at 95% CL. Considering a combinatorial SUSY background contribution with a ratio BR(ll')/BR(ll)=50% (100%) models with S{sub s}{>=}5.5(6.7) can be excluded at 95% CL. For the GMSB model with a slepton NLSP, this translates into a limit of the GMSB parameter {lambda}=40 TeV exceeding the current LEP limits.
Test of lepton flavour universality at LHCb
Lionetto, Federica
2016-01-01
This contribution presents the $R_D{\\ast}$ and $R_K$ measurements, which are a clean probe of lepton flavour universality, and the angular analyses of the $B^0 \\to K^\\ast {0} \\mu^+ \\mu^-$ and $B^0 \\to K^\\ast{0} ~e^+ e^-$ decays, which allow to search for New Physics in rare decays proceeding through ${\\text a} ~b \\to s \\ell^+ \\ell^-$ transition. All measurements have been performed by the LHCb collaboration using the full statistics of LHC Run I. An overview of the ongoing and future measurements is given in the conclusions.
Flavour perception of oxidation in beef.
Campo, M M; Nute, G R; Hughes, S I; Enser, M; Wood, J D; Richardson, R I
2006-02-01
Lipid oxidation is a major factor in meat quality. In order to relate human perceptions of lipid oxidation, as determined by a trained taste panel, to a chemical measurement of oxidation, we studied meat from animals with a wide range of potential oxidation through differences in their PUFA composition and by displaying the meat in high oxygen modified atmosphere packs for varying lengths of time. Meat was obtained from 73 Angus- and Charolais-cross steers from different trials that had been raised on 10 different diets: grass silage (high in C18:3, n-3), cereal concentrate (high in C18:2, n-6), three diets with 3% added fat consisting of three levels of protected lipid supplement (high in C18:2, n-6 and C18:3, n-3, ratio 1:1), a control with Megalac(®) (relatively saturated), three diets with three levels of inclusion of protected fish oil (high in C20:5 n-3 and C22:6 n-3) plus a constant amount of unprotected fish oil and a final diet with an unprotected fish oil control. The longissimus dorsi muscle was excised from the left carcass side, aged vacuum packaged for 10-13 days depending on the projects and frozen for less than eight months. TBARS and sensory analyses were performed on steaks displayed for 0, 4 or 9 days under simulated retail conditions, exposed to light in modified atmosphere packaging (CO(2):O(2); 25:75). Meat oxidation increased throughout display for each of the diets, as shown by a rise in TBARS values. This increase was not linear, differences between 0 and 4 days of display were smaller than between 4 and 9 days of display. The lowest TBARS and lowest increment occurred in the two control diets and the grass-fed animals, probably due to the more saturated fat of meat from animals fed the control diets and the higher content of vitamin E. Sensory attributes were also influenced by time of display. Positive attributes, such as beef flavour or overall liking, decreased throughout display, whereas negative attributes, such as abnormal and
Lepton flavour universality violation from composite muons
Stangl, Peter
2015-01-01
We describe a possibility to explain the $2.6\\sigma$ deviation from lepton flavour universality observed by the LHCb collaboration in $B^+\\to K^+\\ell^+\\ell^-$ decays in the context of minimal composite Higgs models. We find that a sizable degree of compositeness of partially composite muons can lead to a good agreement with the experimental data. Our construction predicts a new physics contribution to $B_s$-$\\bar{B}_s$ mixing. Additionally, it accounts for the deficit in the invisible $Z$ width measured at LEP.
Heavy flavour decay properties with ATLAS
Carli, Ina; The ATLAS collaboration
2016-01-01
We present the results on CP-violation searches in the Bs system, studied in the decay into J/psi phi, and the Bd system through the comparison of the decay time distributions in the flavour specific state J/psi K* and in the CP eigenstate J/psi KS. We additionally present new results in the search for the rare decays of Bs and Bd into mu+mu-. These searches are based on the full sample of data collected by ATLAS at 7 and 8 TeV collision energy. The consistency with the SM and with other available measurements is discussed.
New Physics Search in Flavour Physics
Energy Technology Data Exchange (ETDEWEB)
Hurth, Tobias; /CERN /SLAC
2006-01-04
With the running B, kaon and neutrino physics experiments, flavour physics takes centre stage within today's particle physics. We discuss the opportunities offered by these experiments in our search for new physics beyond the SM and discuss their complementarity to collider physics. We focus on rare B and kaon decays, highlighting specific observables in an exemplary mode. We also comment on the so-called B {yields} {pi}{pi} and B {yields} K{pi} puzzles. Moreover, we briefly discuss the restrictive role of long-distance strong interactions and some new tools such as QCD factorization and SCET to handle them.
International Nuclear Information System (INIS)
Internal and space-time symmetries are discussed in this group of lectures. The first of the lectures deals with an internal symmetry, or rather two related symmetries called charge independence and charge symmetry. The next two discuss space-time symmetries which also hold approximately, but are broken only by the weak forces; that is, these symmetries hold for both the hadronic and electromagnetic forces
B flavour tagging using charm decays at the LHCb experiment
Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Anderson, J.; Andreassi, G.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Gutierrez, O. Aquines; Archilli, F.; d'Argent, P.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Battista, V.; Bay, A.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Bel, L. J.; Bellee, V.; Belloli, N.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bertolin, A.; Bettler, M. -O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Billoir, P.; Bird, T.; Birnkraut, A.; Bizzeti, A.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Braun, S.; Britsch, M.; Britton, T.; Brodzicka, J.; Brook, N. H.; Buchanan, E.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Calvi, M.; Calvo Gomez, M.; Campana, P.; Perez, D. Campora; Capriotti, L.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carniti, P.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Cassina, L.; Garcia, L. Castillo; Cattaneo, M.; Cauet, Ch.; Cavallero, G.; Cenci, R.; Charles, M.; Charpentier, Ph.; Chefdeville, M.; Chen, S.; Cheung, S. -F.; Chiapolini, N.; Chrzaszcz, M.; Vidal, X. Cid; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Cogoni, V.; Cojocariu, L.; Collazuol, G.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Corvo, M.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Crocombe, A.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dall'Occo, E.; Dalseno, J.; David, P. N. Y.; Davis, A.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Simone, P.; Dean, C. -T.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Deleage, N.; Demmer, M.; Derkach, D.; Deschamps, O.; Dettori, F.; Dey, B.; Di Canto, A.; Di Ruscio, F.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dosil Suarez, A.; Dossett, D.; Dovbnya, A.; Dreimanis, K.; Dufour, L.; Dujany, G.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Ely, S.; Esen, S.; Evans, H. M.; Evans, T.; Falabella, A.; Faerber, C.; Farinelli, C.; Farley, N.; Farry, S.; Fay, R.; Ferguson, D.; Fernandez Albor, V.; Ferrari, F.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fohl, K.; Fol, P.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Fu, J.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Gao, Y.; Garcia Pardinas, J.; Tico, J. Garra; Garrido, L.; Gascon, D.; Gaspar, C.; Gauld, R.; Gavardi, L.; Gazzoni, G.; Gerick, D.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Giani, S.; Gibson, V.; Girard, O. G.; Giubega, L.; Gligorov, V. V.; Goebel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gotti, C.; Gandara, M. Grabalosa; Graciani Diaz, R.; Cardoso, L. A. Granado; Grauges, E.; Graverini, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Gruenberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadavizadeh, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Han, X.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Henry, L.; Hernando Morata, J. A.; van Herwijnen, E.; Hess, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Humair, T.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jalocha, J.; Jans, E.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Karodia, S.; Kecke, M.; Kelsey, M.; Kenyon, I. R.; Kenzie, M.; Ketel, T.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Klimaszewski, K.; Kochebina, O.; Kolpin, M.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Kozeiha, M.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Krzemien, W.; Kucewicz, W.; Kucharczyk, M.; Kudryavtsev, V.; Kuonen, A. K.; Kurek, K.; Kvaratskheliya, T.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lanfranchi, G.; Langenbruch, C.; Langhans, B.
2015-01-01
An algorithm is described for tagging the flavour content at production of neutral B mesons in the LHCb experiment. The algorithm exploits the correlation of the flavour of a B meson with the charge of a reconstructed secondary charm hadron from the decay of the other b hadron produced in the proton
Flavour democracy and the lepton-quark hierarchy
International Nuclear Information System (INIS)
The mass hierarchy of the leptons and quarks is interpreted as a consequence of a coherent state phenomenon ('flavour democracy'). It is emphasized that particular forms of the mass matrices can arise from the coherent state basis. The violations of the 'flavour democracy' turn out to be relatively large. Numerical examples are presented. (orig.)
Heavy flavour production in 13 TeV pp collisions
Braun, Svende Annelies
2015-01-01
This summer first data at the unprecedented energy of 13 TeV is collected at the LHC. This opens a new era in searches for new particles and precision tests of the Standard Model. Heavy flavour production plays an important role both as precision QCD test and as backgrounds for new particles. The first measurements of heavy flavour production are presented.
Quark flavour observables in the Littlest Higgs model with T-parity after LHC Run 1
Blanke, Monika; Buras, Andrzej J.; Recksiegel, Stefan
2016-04-01
The Littlest Higgs model with T-parity (LHT) belongs to the simplest new physics scenarios with new sources of flavour and CP violation. The latter originate in the interactions of ordinary quarks and leptons with heavy mirror quarks and leptons that are mediated by new heavy gauge bosons. Also a heavy fermionic top partner is present in this model which communicates with the SM fermions by means of standard W^± and Z^0 gauge bosons. We present a new analysis of quark flavour observables in the LHT model in view of the oncoming flavour precision era. We use all available information on the CKM parameters, lattice QCD input and experimental data on quark flavour observables and corresponding theoretical calculations, taking into account new lower bounds on the symmetry breaking scale and the mirror quark masses from the LHC. We investigate by how much the branching ratios for a number of rare K and B decays are still allowed to depart from their SM values. This includes K^+→ π ^+ν bar{ν }, KL→ π ^0ν bar{ν }, K_L→ μ ^+μ ^-, B→ X_sγ , B_{s,d}→ μ ^+μ ^-, B→ K^{(*)}ℓ ^+ℓ ^-, B→ K^{(*)}ν bar{ν }, and \\varepsilon '/\\varepsilon . Taking into account the constraints from Δ F=2 processes, significant departures from the SM predictions for K^+→ π ^+ν bar{ν } and KL→ π ^0ν bar{ν } are possible, while the effects in B decays are much smaller. In particular, the LHT model favours B(Bs→ μ ^+μ ^-) ≥ B(Bs→ μ ^+μ ^-)_SM, which is not supported by the data, and the present anomalies in B→ K^{(*)}ℓ ^+ℓ ^- decays cannot be explained in this model. With the recent lattice and large N input the imposition of the \\varepsilon '/\\varepsilon constraint implies a significant suppression of the branching ratio for KL→ π ^0ν bar{ν } with respect to its SM value while allowing only for small modifications of K^+→ π ^+ν bar{ν }. Finally, we investigate how the LHT physics could be distinguished from other models by means of
The supersymmetric flavour problem in 5D GUTs and its consequences for LHC phenomenology
Brummer, Felix; Kraml, Sabine
2011-01-01
We study supersymmetric models with a GUT-sized extra dimension, where both the Higgs fields and the SUSY breaking hidden sector are localized on a 4D brane. Exponential wave function profiles of the matter fields give rise to hierarchical structures in the Yukawa couplings and soft terms. Such structures can naturally explain hierarchical fermion masses and mixings, while at the same time alleviating the supersymmetric flavour problem. We discuss two sources of supersymmetry breaking, radion mediation and brane fields, and perform a detailed numerical analysis, thoroughly taking into account the proliferation of unknown O(1) coefficients that occurs in this class of models. It turns out that additional assumptions on supersymmetry breaking are necessary to evade the stringent experimental bounds on lepton flavour violation. The favourable regions of parameter space are then examined with regards to their LHC phenomenology. They generically feature heavy gluinos and squarks beyond current bounds. Lepton flavo...
Factors influencing the flavour of game meat: A review.
Neethling, J; Hoffman, L C; Muller, M
2016-03-01
Flavour is a very important attribute contributing to the sensory quality of meat and meat products. Although the sensory quality of meat includes orthonasal and retronasal aroma, taste, as well as appearance, juiciness and other textural attributes, the focus of this review is primarily on flavour. The influence of species, age, gender, muscle anatomical location, diet, harvesting conditions, ageing of meat, packaging and storage, as well as cooking method on the flavour of game meat are discussed. Very little research is available on the factors influencing the flavour of the meat derived from wild and free-living game species. The aim of this literature review is thus to discuss the key ante- and post-mortem factors that influence the flavour of game meat, with specific focus on wild and free-living South African game species.
Flavour constraints on multi-Higgs-doublet models: Yukawa alignment
Pich, Antonio
2010-01-01
In multi-Higgs-doublet models, the alignment in flavour space of all Yukawa matrices coupling to a given right-handed fermion guarantees the absence of tree-level flavour-changing neutral couplings, while introducing new sources of CP violation. With N Higgs doublets (and no right-handed neutrinos) the Yukawa Lagrangian is characterized by the fermion masses, the CKM quark mixing matrix and 3(N-1) complex couplings. Quantum corrections break the alignment, generating a minimal-flavour-violation structure with flavour-blind phases. The aligned multi-Higgs-doublet models lead to a rich and viable phenomenology with an interesting hierarchy of flavour-changing neutral current effects, suppressing them in light-quark systems while allowing potentially relevant signals in heavy-quark transitions.
Four-Fermion Theories with Exact Chiral Symmetry in Three Dimensions
Schmidt, Daniel; Wipf, Andreas
2016-01-01
We investigate a class of four-fermion theories which includes well-known models like the Gross-Neveu model and the Thirring model. In three spacetime dimensions, they are used to model interesting solid state systems like high temperature superconductors and graphene. Additionally, they serve as toy models to study chiral symmetry breaking (CSB). For any number of fermion flavours the Gross-Neveu model has a broken and a symmetric phase, while the existence of a broken phase in the Thirring model depends on the number of flavours. The critical number of fermion flavours beyond which there exists no CSB is still subject of ongoing discussions. Using SLAC fermions we simulate the Thirring model with exact chiral symmetry. To obtain a chiral condensate one can introduce a symmetry-breaking mass term and carefully study the limits of infinite lattice and zero-mass. So far, we did not see CSB within this approach for the Thirring model with 2 or more (reducible) flavours. The talk presents alternative approaches ...
Comparing Dualities and Gauge Symmetries
De Haro, Sebastian; Butterfield, Jeremy N
2016-01-01
We discuss some aspects of the relation between dualities and gauge symmetries. Both of these ideas are of course multi-faceted, and we confine ourselves to making two points. Both points are about dualities in string theory, and both have the 'flavour' that two dual theories are 'closer in content' than you might think. For both points, we adopt a simple conception of a duality as an 'isomorphism' between theories: more precisely, as appropriate bijections between the two theories' sets of states and sets of quantities. The first point (Section 3) is that this conception of duality meshes with two dual theories being 'gauge related' in the general philosophical sense of being physically equivalent. For a string duality, such as T-duality and gauge/gravity duality, this means taking such features as the radius of a compact dimension, and the dimensionality of spacetime, to be 'gauge'. The second point (Sections 4, 5 and 6) is much more specific. We give a result about gauge/gravity duality that shows its rela...
Deriving diffeomorphism symmetry
Kleppe, Astri
2014-01-01
In an earlier article, we have "derived" space, as a part of the Random Dynamics project. In order to get locality we need to obtain reparametrization symmetry, or equivalently, diffeomorphism symmetry. There we sketched a procedure for how to get locality by first obtaining reparametrization symmetry, or equivalently, diffeomorphism symmetry. This is the object of the present article.
Jaffé, Hans H
1977-01-01
This book, devoted exclusively to symmetry in chemistry and developed in an essentially nonmathematical way, is a must for students and researchers. Topics include symmetry elements and operations, multiple symmetry operations, multiplication tables and point groups, group theory applications, and crystal symmetry. Extensive appendices provide useful tables.
Modelling the effect of oil/fat content in food systems on flavour absorption by LLDPE.
Dekker, M.; Willige, van R.W.G.; Linssen, J.P.H.; Voragen, A.G.J.
2003-01-01
One of the phenomena in food packaging interactions is flavour absorption. Absorption of flavour compounds from food products into food-packaging materials can result in loss of flavour compounds or an unbalance in the flavour profile changing a product's quality. The food matrix influences the amou
Flavour-changing neutral currents in the flavour-blind MSSM at large tanβ
International Nuclear Information System (INIS)
A popular way to avoid too large FCNC in supersymmetric models is the assumption of minimal flavour violation (MFV), where SUSY is broken by a flavour-blind mechanism. We study how loop effects which are enhanced at large tanβ can circumvent the MFV constraint to generate new FCNCs. We show that these effects can be resummed to all orders in perturbation theory in analogy to the tanβ-enhanced corrections to the bottom mass. This procedure yields new Feynman rules which automatically contain the enhanced effects without resorting to the decoupling limit. We also include the enhanced bottom-mass corrections and clarify their dependence on the input scheme. Finally, we study contributions to FCNC observables in B physics resulting from the new Feynman rules
The Strong Interactions, Flavour Physics and Beyond
Zuberi, Saba
In this thesis we use effective field theories of the strong interactions to improve our understanding of several quantities in the Standard Model of particle physics (SM). We also examine constraints on an extension of the SM scalar sector and study the implications for the Higgs mass. We first examine an approach to extracting the Cabibbo-Kobayashi-Maskawa matrix element |Vub| via the relationship between the B meson decays B → X uℓnul and B → Xsgamma, where Xi is any final state hadron containing a quark of flavour i. Model dependence is reduced in this approach since the non-perturbative shape function at leading order is universal and drops out; however the perturbative expansion at next-to-leading order is found to be poorly behaved. We carry out a renormalon analysis of the relationship between these spectra to examine higher order perturbative corrections and compare the fixed-order and log expansions. Our analysis can be used to estimate the perturbative uncertainty in the extraction of |Vub|, which we show to be relatively small. Next we take a step towards the broader goal of summing large phase space logarithms from a variety of jet algorithms using Soft Collinear Effective Theory (SCET). We develop a consistent approach to implementing arbitrary phase space constraints in SCET and demonstrate the connection between cutoffs in SCET and phase space limits. By considering several jet algorithms at next-to-leading order, we gain some insight into factorization of final state jets. In particular, we point out the connection between the ultraviolet regulator and factorization. Finally we consider a scalar sector that contains a colour-octet electroweak-doublet scalar, in addition to the SM Higgs. This extension contains the only scalar representations that Yukawa-couple to quarks and are consistent with minimal flavour violation. We examine constraints from electroweak precision data, direct production from LEPII and the Tevatron, and from flavour
Van Isacker, P
2010-01-01
The use of dynamical symmetries or spectrum generating algebras for the solution of the nuclear many-body problem is reviewed. General notions of symmetry and dynamical symmetry in quantum mechanics are introduced and illustrated with simple examples such as the SO(4) symmetry of the hydrogen atom and the isospin symmetry in nuclei. Two nuclear models, the shell model and the interacting boson model, are reviewed with particular emphasis on their use of group-theoretical techniques.
A tale of two cones: the Higgs Branch of Sp(n) theories with 2n flavours
Ferlito, Giulia
2016-01-01
The purpose of this short note is to highlight a particular phenomenon which concerns the Higgs branch of a certain family of 4d N = 2 theories with SO(2N) flavour symmetry. By studying the Higgs branch as an algebraic variety through Hilbert series techniques we find that it is not a single hyperkahler cone but rather the union of two cones with intersection a hyperkahler subvariety which we specify. This remarkable phenomenon is not only interesting per se but plays a crucial role in understanding the structure of all Higgs branches that are generated by mesons.
Search for lepton flavour violation at HERA
Hennekemper, E; Contreras, J G; Bruncko, D; Henderson, R C W; Martyn, H U; Rostovtsev, A; Olsson, J E; Feltesse, J; Buschhorn, G; Bozovic-Jelisavcic, I; Patel, G D; Pandurovic, M; Picuric, I; Staykova, Z; Povh, B; Campbell, A J; Backovic, S; Nowak, G; Ceccopieri, F; Fischer, D J; Kogler, R; Raicevic, N; Nowak, K; Polifka, R; Cvach, J; Huber, F; Lendermann, V; Mehta, A; Hildebrandt, M; Barrelet, E; Sauvan, E; Bizot, J C; Eisen, E; Sauter, M; Dobre, M; Schoeffel, L; Wunsch, E; Steder, M; Muller, K; Alexa, C; Henschel, H; Kleinwort, C; Papadopoulou, T; Pascaud, C; Pahl, P; Wegener, D; Boudry, V; Zacek, J; Turnau, J; Gogitidze, N; Robmann, R; Cerny, V; Niebuhr, C; Zomer, E; De Wolf, E A; Malinovski, E; Brinkmann, M; Fedotov, A; Schultz-Coulon, H C; Greenshaw, T; Horisberger, R; Mikocki, S; Chekelian, V; Gabathuler, E; Dodonov, V; Morris, J V; Valkarova, A; Glazov, A; Newman, P R; Salek, D; Sefkow, E; Lastovicka-Medin, G; Grab, C; Haidt, D; Grell, B R; Tseepeldorj, B; Toll, T; Van Mechelen, P; Goerlich, L; Bystritskaya, L; Ghazaryan, S; Specka, A; Spaskov, V; Laycock, R; Kluge, T; Fleischer, M; Rotaru, M; Vazdik, Y; von den Driesch, M V; Baghdasaryan, A; Pokorny, B; Panagoulias, I; Andreev, V; Zhang, Z; Felst, R; Lipka, K; Sankey, D P C; Baghdasaryan, S; Tsakov, I; Delcourt, B; Shushkevich, S; Kenyon, I R; Hreus, T; Lebedev, A; Aaron, F D; Habib, S; Coughlan, J A; Vallee, C; Shtarkov, L N; Herbst, M; Dubak, A; Schoning, A; Zhokin, A; Stella, B; Ferencei, J; Rusakov, S; Brisson, V; Osman, S; Favart, L; Dainton, J B; Belov, P; Schmitt, S; Sopicki, P; Soloviev, Y; Zohrabyan, H; Smiljanic, I; List, B; Perez, E; Tran, T H; Milcewicz-Mika, I; List, J; Bracinik, J; Dossanov, A; Traynor, D; Diaconu, C; Klein, M; Kraemer, M; Jung, H; Eckerlin, G; Pitzl, D; Petrukhin, A; Landon, M P J; Gayler, J; Jacquet, M; Delvax, J; Jonsson, L; Grindhammer, G; Bunyatyan, A; Helebrant, C; Hiller, K H; Sykora, T; Placakyte, R; Sloan, T; Cerny, K; Ravdandorj, T; Palichik, V; Fomenko, A; Kostka, P; Truol, P; Kapichine, M; Kretzschmar, J; Marage, P; Tabasco, J E R; Morozov, A; Brandt, G; Meyer, A B; Nikitin, D; Kruger, K; Naumann, T; Janssen, X; Daum, K; Stoicea, G; Zalesak, J; Britzger, D; Meyer, J; Meyer, H; Mudrinic, M; Straumann, U; Moreau, E; Bartel, W; Reimer, P; Kiesling, C; Avila, K B C; South, D; Eliseev, A; Roosen, R; Pirumov, H; Maxfield, S J; Grebenyuk, A; Belousov, A; Makankine, A; Ozerov, D; Hoffmann, D; Urban, K; Thompson, P D; Begzsuren, K; Lange, W; Egli, S; Gouzevitch, M; Levonian, S; Radescu, V; Piec, S; Lubimov, V
2011-01-01
A search for second and third generation scalar and vector leptoquarks produced in ep collisions via the lepton flavour violating processes ep -> mu X and ep -> tau X is performed by the H1 experiment at HERA. The full data sample taken at a centre-of-mass energy root s = 319 GeV is used for the analysis, corresponding to an integrated luminosity of 245 pb(-1) of e(+)p and 166 pb(-1) of e(-)p collision data. No evidence for the production of such leptoquarks is observed in the H1 data. Leptoquarks produced in e(+/-)p collisions with a coupling strength of lambda = 0.3 and decaying with the same coupling strength to a muon-quark pair or a tau-quark pair are excluded at 95\\% confidence level up to leptoquark masses of 712 GeV and 479 GeV, respectively.
Heavy flavour decay properties with ATLAS
AUTHOR|(INSPIRE)INSPIRE-00235989; The ATLAS collaboration
2016-01-01
We present the results on CP-violation searches in the $B_s$ system, studied in the $B_s\\rightarrow J/\\psi \\phi$ decay and the $B_d$ system through the comparison of the decay time distributions in the flavour specific state $J/\\psi\\ K^*$ and in the CP eigenstate $J/\\psi\\ K_s$. We also present new results in the search for the rare decays of $B_d$ and $B_s$ into $\\mu^+\\mu^-$. All results are based on the full sample of data collected during LHC Run 1 by ATLAS at 7 and 8 TeV centre-of-mass energy. The consistency with the SM and with other available measurements is discussed.
Fermion scattering in a gravitational background: electroweak corrections and flavour transitions
International Nuclear Information System (INIS)
We investigate the role of the electroweak corrections to the scattering cross section of Standard Model fermions with gravity. We use both an approach of scattering off an external potential, where the gravitational field is treated as a classical background generated by a heavy source, and the usual interaction based on the one-graviton-exchange. In the potential appoach we consider the fields both of a localized and of a distributed gravitational source of spherical symmetry and uniform density, separating the cases of interactions taking place both in the inner and external regions of the source. This allows to make a distinction between interactions involving neutrinos and dark matter particles with a realistic gravity source, which cover the inner region, and the rest of the Standard model fermions. The role of the gravitationally induced flavour-changing transitions, as well as the flavour diagonal ones, are investigated in the limit of both large and small momentum transfers, deriving the structure of the corresponding Hamiltonian
A SUSY GUT of Flavour with S4 x SU(5) to NLO
Hagedorn, Claudia; Luhn, Christoph
2010-01-01
We construct a realistic Supersymmetric (SUSY) Grand Unified Theory (GUT) of Flavour based on S4 x SU(5), together with an additional (global or local) Abelian symmetry, and study it to next-to-leading order (NLO) accuracy. The model includes a successful description of quark and lepton masses and mixing angles at leading order (LO) incorporating the Gatto-Sartori-Tonin (GST) relation and the Georgi-Jarlskog (GJ) relations. We study the vacuum alignment arising from F-terms to NLO and such corrections are shown to have a negligible effect on the results for fermion masses and mixings achieved at LO. Tri-bimaximal (TB) mixing in the neutrino sector is predicted very accurately up to NLO corrections of order 0.1%. Including charged lepton mixing corrections implies small deviations from TB mixing described by a precise sum rule, accurately maximal atmospheric mixing and a reactor mixing angle close to three degrees.
PREFACE: Symmetries in Science XV
Schuch, Dieter; Ramek, Michael
2012-08-01
Logo Bregenz, the peaceful monastery of Mehrerau and the Opera on the Floating Stage again provided the setting for the international symposium 'Symmetries in Science'. The series which has been running for more than 30 years brings together leading theoreticians whose area of research is, in one way or another, related to symmetry. Since 1992 the meeting took place biannually in Brengez until 2003. In 2009, with the endorsement of the founder, Professor Bruno Gruber, we succeeded in re-establishing the series without external funding. The resounding success of that meeting encouraged us to continue in 2011 and, following on the enthusiasm and positive feedback of the participants, we expect to continue in 2013. Yet again, our meeting in 2011 was very international in flavour and brought together some 30 participants representing 12 nationalities, half of them from countries outside the European Union (from New Zealand to Mexico, Russia to Israel). The broad spectrum, a mixture of experienced experts and highly-motivated newcomers, the intensive exchange of ideas in a harmonious and relaxed atmosphere and the resulting joint projects are probably the secrets of why this meeting is considered to be so special to its participants. At the resumption in 2009 some leading experts and younger scientists from economically weak countries were unable to attend due to the lack of financial resources. This time, with the very worthy and unbureaucratic support of the 'Vereinigung von Freunden und Förderern der J W Goethe-Universität Frankfurt am Main' (in short: 'Friends and Supporters of the Frankfurt University'), it was possible for all candidates to participate. In particular some young, inspired scientists had the chance of presenting their work to a very competent, but also friendly, audience. We wish to thank the 'Freunde und Förderer' for supporting Symmetries in Science XV. Almost all participants contributed to the publication of this Conference Proceedings. There
Risk assessment of flavouring substances used in foods
DEFF Research Database (Denmark)
Norby, Karin; Beltoft, Vibe Meister; Greve, Krestine;
2006-01-01
The aim of the present project, the FLAVIS project, is to perform risk assessment of chemically defined flavouring substances. The evaluations are then presented to the European Food Safety Authority (EFSA) for final adoption in its Scientific Panel on food additives, flavourings, processing aids...... and materials in contact with food. The regulatory background for the work is found in the European Parliament and Council Regulation No. 2232/96 laying down a procedure for the establishment of a list of flavouring substances the use of which will be authorised to the exclusion of all others in the EU...... the approach developed by the “Joint FAO/WHO Expert Committee on Food Additives” (JECFA) and referred to in Commission Regulation EC No. 1565/2000. First, the 2800 flavouring substances are divided into groups of structurally related substances. The Procedure is then a stepwise approach that integrates...
Euroopa Liidu 7. Raamprogrammi projekt FLAVOURE / Marge Malbe
Malbe, Marge, 1968-
2011-01-01
2009. a sai Eesti Maaviljeluse Instituut 843,270.00 € suuruse Euroopa Liidu finantseeringu 3 aastat kestva projekti FLAVOURE (Food and Feed Laboratory of Varied and Outstanding Research in Estonia) läbiviimiseks ja koordineerimiseks
Flavour-changing neutral currents in models with extra ' boson
Indian Academy of Sciences (India)
S Sahoo; L Maharana
2004-09-01
New neutral gauge bosons ' are the features of many models addressing the physics beyond the standard model. Together with the existence of new neutral gauge bosons, models based on extended gauge groups (rank > 4) often predict new charged fermions also. A mixing of the known fermions with new states, with exotic weak-isospin assignments (left-handed singlets and right-handed doublets) will induce tree-level flavour-changing neutral interactions mediated by exchange, while if the mixing is only with new states with ordinary weak-isospin assignments, the flavour-changing neutral currents are mainly due to the exchange of the new neutral gauge boson '. We review flavour-changing neutral currents in models with extra ' boson. Then we discuss some flavour-changing processes forbidden in the standard model and new contributions to standard model processes.
DEFF Research Database (Denmark)
Beltoft, Vibe Meister; Binderup, Mona-Lise; Frandsen, Henrik Lauritz;
The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 59 flavouring substances in the Flavouring Group Evaluation 21, Revision 4, using the Procedure in Commission Regulation (EC) No 1565/2000. This revision i...... of these flavouring substances, the specifications for the materials of commerce have also been considered. Adequate specifications including complete purity criteria and identity for the materials of commerce have been provided for all 41 candidate substances...
Formation of Amino Acid Derived Cheese Flavour Compounds
Smit, B.A.
2004-01-01
Lactic acid bacteria (LAB), among them Lactococcus lactis, are often used for the fermentation of milk into various products, such as cheeses. For their growth and maintenance LAB metabolise milk sugar, protein and fat into various low molecular compounds, which sometimes have strong flavour characteristics. This thesis focuses on the production of one class of these compounds as a model system: aldehydes, in particular the key-flavour compounds 3-methylbutanal and 2-methyl propanal, which ar...
Rare decays of flavoured mesons at the LHC
Puig Navarro, Albert
2016-01-01
In absence of strong, direct signs of New Physics at the LHC, rare decays of heavy flavoured hadrons constitute an ideal laboratory for indirectly exploring energies beyond those of the LHC in order to look for deviations from the Standard Model. The main results regarding flavour changing neutral current transitions obtained at the LHC are presented here, with particular emphasis put on $b \\to s$ transitions, in which tensions with the Standard Model have been observed.
Theory of electric dipole moments and lepton flavour violation
Jung, Martin
2016-01-01
Electric dipole moments and charged-lepton flavour-violating processes are extremely sensitive probes for new physics, complementary to direct searches as well as flavour-changing processes in the quark sector. Beyond the "smoking-gun" feature of a potential significant measurement, however, it is crucial to understand their implications for new physics models quantitatively. The corresponding multi-scale problem of relating the existing high-precision measurements to fundamental parameters c...
The negative binomial distribution in quark jets with fixed flavour
Alberto GiovanniniTurin U. & INFN, Turin; Sergio Lupia(Munich, Max Planck Inst.); Roberto Ugoccioni(Lund U.)
2015-01-01
We show that both the multiplicity distribution and the ratio of factorial cumulants over factorial moments for 2-jet events in e+e- annihilation at the Z^0 peak can be well reproduced by the weighted superposition of two negative binomial distributions, associated to the contribution of $b\\bar b$ and light flavoured events respectively. The negative binomial distribution is then suggested to describe the multiplicity distribution of 2-jet events with fixed flavour.
Signatures of top flavour-changing dark matter
D’Hondt, Jorgen; Mariotti, Alberto; Mawatari, Kentarou; Moortgat, Seth; Tziveloglou, Pantelis; Van Onsem, Gerrit
2016-01-01
We develop the phenomenology of scenarios in which a dark matter candidate interacts with a top quark through flavour-changing couplings, employing a simplified dark matter model with an s -channel vector-like mediator. We study in detail the top-charm flavour-changing interaction, by investigating the single top plus large missing energy signature at the LHC as well as constraints from the relic density and direct and indirect dark matter detection experiments. We present strategies to disti...
Impact on odorant partition coefficients and flavour perception
Rusu, Manuela
2007-01-01
Foods are complex multi-component systems which are composed of volatile and non-volatile substances. The flavour profile of a food is an important criterion for the selection of our foodstuffs. The main objective of this study was the clarification of the complex relationships of the flavour release as a function of the composition of the food matrix at molecular level. Therefore the influence of matrix effects onto the partition coefficients, odour activity values and sens...
Application of Electrostatic Extrusion – Flavour Encapsulation and Controlled Release
Manojlovic, Verica; Rajic, Nevenka; Djonlagic, Jasna; Obradovic, Bojana; Nedovic, Viktor; Bugarski, Branko
2008-01-01
The subject of this study was the development of flavour alginate formulations aimed for thermally processed foods. Ethyl vanilline was used as the model flavour compound. Electrostatic extrusion was applied for the encapsulation of ethyl vanilline in alginate gel microbeads. The obtained microbeads with approx. 10 % w/w of ethyl vanilline encapsulated in about 2 % w/w alginate were uniformly sized spheres of about 450 μm. Chemical characterization by H-NMR spectroscopy revealed that the algi...
Brading, Katherine; Castellani, Elena
2010-01-01
Preface; Copyright acknowledgements; List of contributors; 1. Introduction; Part I. Continuous Symmetries: 2. Classic texts: extracts from Weyl and Wigner; 3. Review paper: On the significance of continuous symmetry to the foundations of physics C. Martin; 4. The philosophical roots of the gauge principle: Weyl and transcendental phenomenological idealism T. Ryckman; 5. Symmetries and Noether's theorems K. A. Brading and H. R. Brown; 6. General covariance, gauge theories, and the Kretschmann objection J. Norton; 7. The interpretation of gauge symmetry M. Redhead; 8. Tracking down gauge: an ode to the constrained Hamiltonian formalism J. Earman; 9. Time-dependent symmetries: the link between gauge symmetries and indeterminism D. Wallace; 10. A fourth way to the Aharanov-Bohm effect A. Nounou; Part II. Discrete Symmetries: 11. Classic texts: extracts from Lebniz, Kant and Black; 12. Review paper: Understanding permutation symmetry S. French and D. Rickles; 13. Quarticles and the identity of discernibles N. Hugget; 14. Review paper: Handedness, parity violation, and the reality of space O. Pooley; 15. Mirror symmetry: what is it for a relational space to be orientable? N. Huggett; 16. Physics and Leibniz's principles S. Saunders; Part III. Symmetry Breaking: 17: Classic texts: extracts from Curie and Weyl; 18. Extract from G. Jona-Lasinio: Cross-fertilization in theoretical physics: the case of condensed matter and particle physics G. Jona-Lasinio; 19. Review paper: On the meaning of symmetry breaking E. Castellani; 20. Rough guide to spontaneous symmetry breaking J. Earman; 21. Spontaneous symmetry breaking: theoretical arguments and philosophical problems M. Morrison; Part IV. General Interpretative Issues: 22. Classic texts: extracts from Wigner; 23. Symmetry as a guide to superfluous theoretical structure J. Ismael and B. van Fraassen; 24. Notes on symmetries G. Belot; 25. Symmetry, objectivity, and design P. Kosso; 26. Symmetry and equivalence E. Castellani.
DEFF Research Database (Denmark)
Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister;
The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 14 flavouring substances in the Revision 1 of Flavouring Group Evaluation 66, using the Procedure in Commission Regulation (EC) No 1565/2000. None of the s...
Rasin, A
1994-01-01
We discuss the idea of approximate flavor symmetries. Relations between approximate flavor symmetries and natural flavor conservation and democracy models is explored. Implications for neutrino physics are also discussed.
Directory of Open Access Journals (Sweden)
Joe Rosen
2005-12-01
Full Text Available Abstract: The symmetry principle is described in this paper. The full details are given in the book: J. Rosen, Symmetry in Science: An Introduction to the General Theory (Springer-Verlag, New York, 1995.
Whiley, Henry
2013-01-01
Stilton is a blue-veined cheese made from pasteurised milk. The diversity of the microflora found within the cheese helps develop the unique flavour and aroma of Stilton compared to other blue cheese. However, this flora is not controlled and so product may be variable. A small-scale cheese model was developed to allow examination of the effect of different microflora on flavour production in a controlled way. Texture analysis, water activity and viable count of the cheese models were comp...
Czaban, Christopher
2016-01-01
QCD at zero baryon density in the limit of infinite quark mass undergoes a first order deconfinement phase transition at a critical temperature $T_c$ corresponding to the breaking of the global centre symmetry. In the presence of dynamical quarks this symmetry is explicitly broken. Lowering the quark mass the first order phase transition weakens and terminates in a second order Z(2) point. Beyond this line confined and deconfined regions are analytically connected by a crossover transition. As the continuum limit is approached (i.e. the lattice spacing is decreased) the region of first order transitions expands towards lower masses. We study the deconfinement critical point with standard Wilson fermions and $N_f=2$ flavours. To this end we simulate several kappa values on $N_\\tau=8$ and various aspect ratios in order to extrapolate to the thermodynamic limit, applying finite size scaling. We estimate if and when a continuuum extrapolation is possible.
Energy Technology Data Exchange (ETDEWEB)
Nilles, Hans Peter [Bonn Univ. (Germany). Bethe Center for Theoretical Physics; Bonn Univ. (Germany). Physikalisches Inst.; Ratz, Michael [Technische Univ. Muenchen, Garching (Germany). Physik-Department; Vaudrevange, Patrick K.S. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2012-04-15
Discrete (family) symmetries might play an important role in models of elementary particle physics. We discuss the origin of such symmetries in the framework of consistent ultraviolet completions of the standard model in field and string theory. The symmetries can arise due to special geometrical properties of extra compact dimensions and the localization of fields in this geometrical landscape. We also comment on anomaly constraints for discrete symmetries.
Nilles, H. P.; Ratz, M.; Vaudrevange, P. K. S.
2012-01-01
Discrete (family) symmetries might play an important role in models of elementary particle physics. We discuss the origin of such symmetries in the framework of consistent ultraviolet completions of the standard model in field and string theory. The symmetries can arise due to special geometrical properties of extra compact dimensions and the localization of fields in this geometrical landscape. We also comment on anomaly constraints for discrete symmetries.
Neutrinos and flavor symmetries
Tanimoto, Morimitsu
2015-07-01
We discuss the recent progress of flavor models with the non-Abelian discrete symmetry in the lepton sector focusing on the θ13 and CP violating phase. In both direct approach and indirect approach of the flavor symmetry, the non-vanishing θ13 is predictable. The flavor symmetry with the generalised CP symmetry can also predicts the CP violating phase. We show the phenomenological analyses of neutrino mixing for the typical flavor models.
Neutrinos and flavor symmetries
Energy Technology Data Exchange (ETDEWEB)
Tanimoto, Morimitsu
2015-07-15
We discuss the recent progress of flavor models with the non-Abelian discrete symmetry in the lepton sector focusing on the θ{sub 13} and CP violating phase. In both direct approach and indirect approach of the flavor symmetry, the non-vanishing θ{sub 13} is predictable. The flavor symmetry with the generalised CP symmetry can also predicts the CP violating phase. We show the phenomenological analyses of neutrino mixing for the typical flavor models.
Polynomial Graphs and Symmetry
Goehle, Geoff; Kobayashi, Mitsuo
2013-01-01
Most quadratic functions are not even, but every parabola has symmetry with respect to some vertical line. Similarly, every cubic has rotational symmetry with respect to some point, though most cubics are not odd. We show that every polynomial has at most one point of symmetry and give conditions under which the polynomial has rotational or…
Chiral symmetry and chiral-symmetry breaking
Energy Technology Data Exchange (ETDEWEB)
Peskin, M.E.
1982-12-01
These lectures concern the dynamics of fermions in strong interaction with gauge fields. Systems of fermions coupled by gauge forces have a very rich structure of global symmetries, which are called chiral symmetries. These lectures will focus on the realization of chiral symmetries and the causes and consequences of thier spontaneous breaking. A brief introduction to the basic formalism and concepts of chiral symmetry breaking is given, then some explicit calculations of chiral symmetry breaking in gauge theories are given, treating first parity-invariant and then chiral models. These calculations are meant to be illustrative rather than accurate; they make use of unjustified mathematical approximations which serve to make the physics more clear. Some formal constraints on chiral symmetry breaking are discussed which illuminate and extend the results of our more explicit analysis. Finally, a brief review of the phenomenological theory of chiral symmetry breaking is presented, and some applications of this theory to problems in weak-interaction physics are discussed. (WHK)
Account of Nonpolynomial SU(3)-Breaking Effects By Use of Quantum Groups As Flavor Symmetries
Gavrilik, A M
1998-01-01
Using instead of ordinary flavour symmetries SU(n_f) their corresponding quantum (q-deformed) analogs yields new baryon mass sum rules of extreme accuracy. We show, in the 3-flavour case, that such approach accounts for highly nonlinear (nonpolynomial) SU(3)-breaking effects both in the octet and decuplet baryon masses. A version of this approach is considered that involves q-covariant ingredients in the mass operator. The resulting new 'q-deformed' mass relation (q-MR) is simpler than previously derived q-MRs, but requires, for its empirical validity, a fitting to fix the value of the deformation parameter q. Well-known Gell-Mann--Okubo (GMO) octet mass sum rule is found to result not only from usual SU(3), but also from some exotic symmetry corresponding to the q=-1 (i.e., singular) limit of the q-algebra U_q(su_3).
Kogut, J B
2010-01-01
QCD with two flavours of massless colour-sextet quarks is considered as a model for conformal/walking Technicolor. If this theory possess an infrared fixed point, as indicated by 2-loop perturbation theory, it is a conformal(unparticle) field theory. If, on the other hand, a chiral condensate forms on the weak-coupling side of this would-be fixed point, the theory remains confining. The only difference between such a theory and regular QCD is that there is a range of momentum scales over which the coupling constant runs very slowly (walks). In this first analysis, we simulate the lattice version of QCD with two flavours of staggered quarks at finite temperatures on lattices of temporal extent $N_t=4$ and 6. The deconfinement and chiral-symmetry restoration couplings give us a measure of the scales associated with confinement and chiral-symmetry breaking. We find that, in contrast to what is seen with fundamental quarks, these transition couplings are very different. $\\beta=6/g^2$ for each of these transitions...
Search for lepton flavour violation at HERA
Energy Technology Data Exchange (ETDEWEB)
Aaron, F.D. [National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Bucharest Univ. (Romania). Faculty of Physics; Alexa, C. [National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Andreev, V. [Lebedev Physical Institute, Moscow (RU)] (and others)
2011-03-15
A search for second and third generation scalar and vector leptoquarks produced in ep collisions via the lepton flavour violating processes ep{yields}{mu}X and ep{yields}{tau}X is performed by the H1 experiment at HERA. The full data sample taken at a centre-of-mass energy {radical}(s)=319 GeV is used for the analysis, corresponding to an integrated luminosity of 245 pb{sup -1} of e{sup +}p and 166 pb{sup -1} of e{sup -}p collision data. No evidence for the production of such leptoquarks is observed in the H1 data. Leptoquarks produced in e{sup {+-}}p collisions with a coupling strength of {lambda}=0.3 and decaying with the same coupling strength to a muon-quark pair or a tau-quark pair are excluded at 95% confidence level up to leptoquark masses of 712 GeV and 479 GeV, respectively. (orig.)
Flavour physics in the soft wall model
Archer, Paul R.; Huber, Stephan J.; Jäger, Sebastian
2011-12-01
We extend the description of flavour that exists in the Randall-Sundrum (RS) model to the soft wall (SW) model in which the IR brane is removed and the Higgs is free to propagate in the bulk. It is demonstrated that, like the RS model, one can generate the hierarchy of fermion masses by localising the fermions at different locations throughout the space. However, there are two significant differences. Firstly the possible fermion masses scale down, from the electroweak scale, less steeply than in the RS model and secondly there now exists a minimum fermion mass for fermions sitting towards the UV brane. With a quadratic Higgs VEV, this minimum mass is about fifteen orders of magnitude lower than the electroweak scale. We derive the gauge propagator and despite the KK masses scaling as m_n^2 ˜ n , it is demonstrated that the coefficients of four fermion operators are not divergent at tree level. FCNC's amongst kaons and leptons are considered and compared to calculations in the RS model, with a brane localised Higgs and equivalent levels of tuning. It is found that since the gauge fermion couplings are slightly more universal and the SM fermions typically sit slightly further towards the UV brane, the contributions to observables such as ɛ K and Δ m K , from the exchange of KK gauge fields, are significantly reduced.
Relic neutrino decoupling with flavour oscillations revisited
de Salas, Pablo F
2016-01-01
We study the decoupling process of neutrinos in the early universe in the presence of three-flavour oscillations. The evolution of the neutrino spectra is found by solving the corresponding momentum-dependent kinetic equations for the neutrino density matrix, including for the first time the proper collision integrals for both diagonal and off-diagonal elements. This improved calculation modifies the evolution of the off-diagonal elements of the neutrino density matrix and changes the deviation from equilibrium of the frozen neutrino spectra. However, it does not vary the contribution of neutrinos to the cosmological energy density in the form of radiation, usually expressed in terms of the effective number of neutrinos, N_eff. We find a value of N_eff=3.045, in agreement with previous theoretical calculations and consistent with the latest analysis of Planck data. This result does not depend on the ordering of neutrino masses. We also consider the effect of non-standard neutrino-electron interactions (NSI), ...
Flavour singlets in gauge theory as Permutations
Kimura, Yusuke; Suzuki, Ryo
2016-01-01
Gauge-invariant operators can be specified by equivalence classes of permutations. We develop this idea concretely for the singlets of the flavour group $SO(N_f)$ in $U(N_c)$ gauge theory by using Gelfand pairs and Schur-Weyl duality. The singlet operators, when specialised at $N_f =6$, belong to the scalar sector of ${\\cal N}=4$ SYM. A simple formula is given for the two-point functions in the free field limit of $g_{YM}^2 =0$. The free two-point functions are shown to be equal to the partition function on a 2-complex with boundaries and a defect, in a topological field theory of permutations. The permutation equivalence classes are Fourier transformed to a representation basis which is orthogonal for the two-point functions at finite $N_c , N_f$. Counting formulae for the gauge-invariant operators are described. The one-loop mixing matrix is derived as a linear operator on the permutation equivalence classes.
Symmetries in subatomic systems
International Nuclear Information System (INIS)
The underlying common themes of the EJC-2010 are symmetries and symmetry violation in relation to nucleon structure, nuclear geometry, isospin and reaction dynamics. The parity violation in electron scattering is the unique probe of strange quarks in nucleons and of neutron skin in heavy nuclei. The use of dynamical symmetries or spectrum generating algebras for the solution of the nuclear many-body problem is reviewed. We also discuss the impact of the symmetries of quantum chromodynamics on the observed properties of hadrons and strongly interacting matter. Mean field approaches are widely used to study nuclear structure properties and correlations between nucleons are treated by symmetry-violating mean field approaches and symmetry properties are currently treated with beyond mean field approaches by using projection techniques. A paper focuses on properties of giant resonances (GR) and particularly on the relationship between GR and isospin symmetry. This document gathers the papers and/or slides of 10 presentations. (A.C.)
Symmetry and symmetry breaking in quantum mechanics
International Nuclear Information System (INIS)
In the world of infinitely small, the world of atoms, nuclei and particles, the quantum mechanics enforces its laws. The discovery of Quanta, this unbelievable castration of the Possible in grains of matter and radiation, in discrete energy levels compels us of thinking the Single to comprehend the Universal. Quantum Numbers, magic Numbers and Numbers sign the wave. The matter is vibration. To describe the music of the world one needs keys, measures, notes, rules and partition: one needs quantum mechanics. The particles reduce themselves not in material points as the scholars of the past centuries thought, but they must be conceived throughout the space, in the accomplishment of shapes of volumes. When Einstein asked himself whether God plays dice, there was no doubt among its contemporaries that if He exists He is a geometer. In a Nature reduced to Geometry, the symmetries assume their role in servicing the Harmony. The symmetries allow ordering the energy levels to make them understandable. They impose there geometrical rules to the matter waves, giving them properties which sometimes astonish us. Hidden symmetries, internal symmetries and newly conceived symmetries have to be adopted subsequently to the observation of some order in this world of Quanta. In turn, the symmetries provide new observables which open new spaces of observation
Nearly tri-bimaximal mixing in the S_3 flavour symmetry
Mondragón, A; Peinado, E
2007-01-01
We present an analysis of the theoretical neutrino mixing matrix, V_{PMNS}^{th}, previously derived in the framework of the minimal S_3-invariant extension of the Standard Model. All entries in the neutrino mixing matrix, V_{PMNS}^{th}, the mixing angles and the Majorana phases are given as exact, explicit analytical functions of the mass ratios of the charged leptons and neutrinos, and one Dirac phase, in excellent agreement with the the latest experimental data. Here, it will be shown that all entries in V_{PMNS}^{th} are numerically very close to the tri-bimaximal form of the neutrino mixing matrix, so that V_{PMNS}^{th} may be written as V^{tri}+\\Delta V_{PMNS}^{tri}. The small correction \\Delta V_{PMNS}^{tri} is expressed as a sum of two terms: first, a small correction term proportional to m_{e}/m_{\\mu} depending only on the charged lepton mass ratios and, second, a Cabbibo-like, small term, \\delta t_{12}, which is a function of both the charged lepton and the neutrino mass ratios.
Update of the flavour-physics constraints in the NMSSM
Domingo, Florian
2015-01-01
We consider the impact of several flavour-changing observables in the $B$- and the Kaon sectors on the parameter space of the NMSSM, in a minimal flavour violating version of this model. Our purpose consists in updating our previous results in arXiv:0710.3714 and designing an up-to-date flavour test for the public package NMSSMTools. We provide details concerning our implementation of the constraints in a series of brief reviews of the current status of the considered channels. Finally, we present a few consequences of these flavour constraints for the NMSSM, turning to two specific scenarios: one is characteristic of the MSSM-limit and illustrates the workings of charged-Higgs and genuinely supersymmetric contributions to flavour-changing processes; the second focus is a region where a light CP-odd Higgs is present. Strong limits are found whenever an enhancement factor - large $\\tan\\beta$, light $H^{\\pm}$, resonant pseudoscalar - comes into play.
Mass Insertions vs. Mass Eigenstates calculations in Flavour Physics
Dedes, A; Rosiek, J; Suxho, K; Tamvakis, K
2015-01-01
We present and prove a theorem of matrix analysis, the Flavour Expansion Theorem (or FET), according to which, an analytic function of a Hermitian matrix can be expanded polynomially in terms of its off-diagonal elements with coefficients being the divided differences of the analytic function and arguments the diagonal elements of the Hermitian matrix. The theorem is applicable in case of flavour changing amplitudes. At one-loop level this procedure is particularly natural due to the observation that every loop function in the Passarino-Veltman basis can be recursively expressed in terms of divided differences. FET helps to algebraically translate an amplitude written in mass eigenbasis into flavour mass insertions, without performing diagrammatic calculations in flavour basis. As a non-trivial application of FET up to a third order, we demonstrate its use in calculating strong bounds on the real parts of flavour changing mass insertions in the up- squark sector of the MSSM from neutron Electric Dipole Moment...
Mixed symmetry tensors in the worldline formalism
Corradini, Olindo
2016-01-01
We consider the first quantised approach to quantum field theory coupled to a non-Abelian gauge field. Representing the colour degrees of freedom with a single family of auxiliary variables the matter field transforms in a reducible representation of the gauge group which - by adding a suitable Chern-Simons term to the particle action - can be projected onto a chosen fully (anti-)symmetric representation. By considering F families of auxiliary variables, we describe how to extend the model to arbitrary tensor products of F reducible representations, which realises a U(F) "flavour" symmetry on the worldline particle model. Gauging this symmetry allows the introduction of constraints on the Hilbert space of the colour fields which can be used to project onto an arbitrary irreducible representation, specified by a certain Young Tableau. In particular the occupation numbers of the wavefunction - i.e. the lengths of the columns (rows) of the Young Tableau - are fixed through the introduction of Chern-Simons terms....
Mixed symmetry tensors in the worldline formalism
Corradini, Olindo; Edwards, James P.
2016-05-01
We consider the first quantised approach to quantum field theory coupled to a non-Abelian gauge field. Representing the colour degrees of freedom with a single family of auxiliary variables the matter field transforms in a reducible representation of the gauge group which — by adding a suitable Chern-Simons term to the particle action — can be projected onto a chosen fully (anti-)symmetric representation. By considering F families of auxiliary variables, we describe how to extend the model to arbitrary tensor products of F reducible representations, which realises a U( F ) "flavour" symmetry on the world-line particle model. Gauging this symmetry allows the introduction of constraints on the Hilbert space of the colour fields which can be used to project onto an arbitrary irreducible representation, specified by a certain Young tableau. In particular the occupation numbers of the wavefunction — i.e. the lengths of the columns (rows) of the Young tableau — are fixed through the introduction of Chern-Simons terms. We verify this projection by calculating the number of colour degrees of freedom associated to the matter field. We suggest that, using the worldline approach to quantum field theory, this mechanism will allow the calculation of one-loop scattering amplitudes with the virtual particle in an arbitrary representation of the gauge group.
Neutrino Mass and Mixing with Discrete Symmetry
King, Stephen F
2013-01-01
This is a review article about neutrino mass and mixing and flavour model building strategies based on discrete family symmetry. After a pedagogical introduction and overview of the whole of neutrino physics, we focus on the PMNS mixing matrix and the latest global fits following the Daya Bay and RENO experiments which measure the reactor angle. We then describe the simple bimaximal, tri-bimaximal and golden ratio patterns of lepton mixing and the deviations required for a non-zero reactor angle, with solar or atmospheric mixing sum rules resulting from charged lepton corrections or residual trimaximal mixing. The different types of seesaw mechanism are then reviewed as well as the sequential dominance mechanism. We then give a mini-review of finite group theory, which may be used as a discrete family symmetry broken by flavons either completely, or with different subgroups preserved in the neutrino and charged lepton sectors. These two approaches are then reviewed in detail in separate chapters including mec...
International Nuclear Information System (INIS)
Symmetry, disymmetry, chirality etc. are well-known topics in chemistry. But they cannot only be found on the molecular level of matter. Atoms and elementary particles in physics are also characterized by particular symmetry groups. Even living organisms and populations on the macroscopic level have functional properties of symmetry. The whole physical, chemical, and biological evolution seems to be regulated by the emergence of new symmetries and the breaking down of old ones. One is reminded of Heisenberg's famous statement: 'Die letzte Wurzel der Erscheinungen ist also nicht die Materie, sondern das mathematische Gesetz, die Symmetrie, die mathematische Form' (Wandlungen in den Grundlagen der Naturwissenschaften, 1959). Historically the belief in symmetry and simplicity of nature has a long philosophical tradition from the Pythagoreans, Plato and Greek astronomers to Kepler and modern scientists. Today, 'symmetries in nature' is a common topic of mathematics, physics, chemistry, and biology. A lot of Nobel prizes were given in honour of inquiries concerning symmetries in nature. The fascination of symmetries is not only motivated by science, but by art and religion too. Therefore 'symmetris in nature' is an interdisciplinary topic which may help to overcome C.P. Snow's 'Two Cultures' of natural sciences and humanities. (author) 17 refs., 21 figs
Bottom-Up Discrete Symmetries for Cabibbo Mixing
Varzielas, Ivo de Medeiros; Talbert, Jim
2016-01-01
We perform a bottom-up search for discrete non-Abelian symmetries capable of quantizing the Cabibbo angle that parameterizes CKM mixing. Given a particular Abelian symmetry structure in the up and down sectors, we construct representations of the associated residual generators which explicitly depend on the degrees of freedom present in our effective mixing matrix. We then discretize those degrees of freedom and utilize the Groups, Algorithms, Programming (GAP) package to close the associated finite groups. This short study is performed in the context of recent results indicating that, without resorting to special model-dependent corrections, no small-order finite group can simultaneously predict all four parameters of the three-generation CKM matrix and that only groups of $\\mathcal{O}(10^{2})$ can predict the analogous parameters of the leptonic PMNS matrix, regardless of whether neutrinos are Dirac or Majorana particles. Therefore a natural model of flavour might instead incorporate small(er) finite groups...
Generalised Geometrical CP Violation in a $T^{\\prime}$ Lepton Flavour Model
Girardi, Ivan; Petcov, S T; Spinrath, Martin
2014-01-01
We analyse the interplay of generalised CP transformations and the non-Abelian discrete group $T^{\\prime}$ and use the semi-direct product $G_f= T^{\\prime}\\rtimes H_{\\text{CP}}$, as family symmetry acting in the lepton sector. The family symmetry is shown to be spontaneously broken in a geometrical manner. In the resulting flavour model, naturally small Majorana neutrino masses for the light active neutrinos are obtained through the type I see-saw mechanism. The known masses of the charged leptons, lepton mixing angles and the two neutrino mass squared differences are reproduced by the model with a good accuracy. The model allows for two neutrino mass spectra with normal ordering (NO) and one with inverted ordering (IO). For each of the three spectra the absolute scale of neutrino masses is predicted with relatively small uncertainty. The value of the Dirac CP violation (CPV) phase $\\delta$ in the lepton mixing matrix is predicted to be $\\delta \\cong \\pi/2~{\\rm or}~ 3\\pi/2$. Thus, the CP violating effects in ...
η'-π mass splitting in full QCD from negative flavour numbers
International Nuclear Information System (INIS)
η'-π splitting in full QCD can be estimated extrapolating from negative to positive flavour numbers. Our results show a flavour dependence consistent with the Witten Veneziano formula based on the U(1) anomaly. (orig.)
Impact of sterile neutrinos in lepton flavour violating processes
De Romeri, Valentina
2016-05-01
We discuss charged lepton flavour violating processes occurring in minimal extensions of the Standard Model via the addition of sterile fermions. We firstly investigate the possibility of their indirect detection at a future high-luminosity Z-factory (such as FCC-ee). Rare decays such as Z → l 1 ± l 2 ± can indeed be complementary to low-energy (high-intensity) observables of lepton flavour violation. We further consider a sterile neutrino-induced charged lepton flavour violating process occurring in the presence of muonic atoms: their (Coulomb enhanced) decay into a pair of electrons μ¯e¯ → e¯e¯. Our study reveals that, depending on their mass range and on the active-sterile mixing angles, sterile neutrinos can give significant contributions to the above mentioned observables, some of them even lying within present and future sensitivity of dedicated cLFV experiments and of FCC-ee.
The neutron EDM vs up and charm flavour violation
Sala, Filippo
2014-01-01
We derive a strong bound on the chromo-electric dipole moment of the charm quark, and we quantify its impact on models that allow for a sizeable flavour violation in the up quark sector. In particular we show how the constraints coming from the charm and up CEDMs limit the size of new physics contributions to direct flavour violation in D meson decays. We also specialize our analysis to the cases of split-families Supersymmetry and composite Higgs models. The results we expose motivate an increase in experimental sensitivity to fundamental hadronic dipoles, and a further exploration of the SM contribution to both flavour violating D decays and nuclear electric dipole moments.
Signatures of top flavour-changing dark matter
D'Hondt, Jorgen; Mawatari, Kentarou; Moortgat, Seth; Tziveloglou, Pantelis; Van Onsem, Gerrit
2015-01-01
We develop the phenomenology of scenarios in which a dark matter candidate interacts with a top quark through flavour-changing couplings, employing a simplified dark matter model with an s-channel vector-like mediator. We study in detail the top-charm flavour-changing interaction, by investigating the single top plus large missing energy signature at the LHC as well as constraints from the relic density and direct and indirect dark matter detection experiments. We present strategies to distinguish between the top-charm and top-up flavour-changing models by taking advantage of the lepton charge asymmetry as well as by using charm-tagging techniques on an extra jet. We also show the complementarity between the LHC and canonical dark matter experiments in exploring the viable parameter space of the models.
Heavy flavour measurements with ALICE at the LHC
Energy Technology Data Exchange (ETDEWEB)
Castillo Castellanos, Javier [service de physique nucleaire - SPhN, IRFU, CEA-Saclay, 91191 Gif-sur-Yvette Cedex (France)
2010-07-01
ALICE is the LHC experiment dedicated to the study of heavy-ion collisions. The main purpose of ALICE is to investigate the properties of a state of deconfined nuclear matter, the Quark Gluon Plasma. Heavy flavour measurements will play a crucial role in this investigation. The physics programme of ALICE has started by studying proton-proton collisions at unprecedented high energies. We will present the first results on open heavy flavour and quarkonia in proton-proton collisions at {radical}(s)=7 TeV measured by the ALICE experiment at both mid- and forward-rapidities. We will conclude with the prospects for heavy flavour and quarkonium measurements in both proton-proton and nucleus-nucleus collisions. (author)
LHCb: Optimization and Calibration of Flavour Tagging Algorithms for the LHCb experiment
Falabella, A
2013-01-01
The LHCb purposes are to make precise measurements in $B$ and $D$ meson decays. In particular in time-dependent CP violation studies the determination of $B$ flavour at production ("Flavour Tagging") is fundamental. The performances and calibration of the flavour tagging algorithms with 2011 data collected by LHCb are reported. The performances of the flavour tagging algorithms on the relevant CP violation and asymmetry studies are also reported.
LHCb: Optimization and Calibration of Flavour Tagging Algorithms for the LHCb experiment
Falabella, A
2013-01-01
The LHCb purposes are to make precise measurements of $B$ and $D$ meson decays. In particular in time-dependent CP violation studies the determination of $B$ flavour at production is fundamental. This is known as "flavour tagging" and at LHCb it is performed with several algorithms. The performances and calibration of the flavour tagging algorithms with 2011 data collected by LHCb are reported. Also the performances of the flavour tagging algorithms in the relevant CP violation and asymmetry studies are also reported.
Minimal flavour violation in the quark and lepton sector and beyond
Energy Technology Data Exchange (ETDEWEB)
Uhlig, S.L.
2008-01-07
We address to explain the matter-antimatter asymmetry of the universe in a framework that generalizes the quark minimal flavour violation hypothesis to the lepton sector. We study the impact of CP violation present at low and high energies and investigate the existence of correlations among leptogenesis and lepton flavour violation. Further we present an approach alternative to minimal flavour violation where the suppression of flavour changing transitions involving quarks and leptons is governed by hierarchical fermion wave functions. (orig.)
Checking flavour models at neutrino facilities
Energy Technology Data Exchange (ETDEWEB)
Meloni, Davide, E-mail: meloni@fis.uniroma3.it
2014-01-20
In the recent years, the industry of model building has been the subject of the intense activity, especially after the measurement of a relatively large values of the reactor angle. Special attention has been devoted to the use of non-abelian discrete symmetries, thanks to their ability of reproducing some of the relevant features of the neutrino mixing matrix. In this Letter, we consider two special relations between the leptonic mixing angles, arising from models based on S{sub 4} and A{sub 4}, and study whether, and to which extent, they can be distinguished at superbeam facilities, namely T2K, NOνA and T2HK.
From physical symmetries to emergent gauge symmetries
Barceló, Carlos; Di Filippo, Francesco; Garay, Luis J
2016-01-01
Gauge symmetries indicate redundancies in the description of the relevant degrees of freedom of a given field theory and restrict the nature of observable quantities. One of the problems faced by emergent theories of relativistic fields is to understand how gauge symmetries can show up in systems that contain no trace of these symmetries at a more fundamental level. In this paper we start a systematic study aimed to establish a satisfactory mathematical and physical picture of this issue, dealing first with abelian field theories. We discuss how the trivialization, due to the decoupling and lack of excitation of some degrees of freedom, of the Noether currents associated with physical symmetries leads to emergent gauge symmetries in specific situations. An example of a relativistic field theory of a vector field is worked out in detail in order to make explicit how this mechanism works and to clarify the physics behind it. The interplay of these ideas with well-known results of importance to the emergent grav...
Lepton mixing and discrete symmetries
Hernandez, D.; Smirnov, A. Yu.
2012-09-01
The pattern of lepton mixing can emerge from breaking a flavor symmetry in different ways in the neutrino and charged lepton Yukawa sectors. In this framework, we derive the model-independent conditions imposed on the mixing matrix by the structure of discrete groups of the von Dyck type which include A4, S4, and A5. We show that, in general, these conditions lead to at least two equations for the mixing parameters (angles and CP phase δ). These constraints, which correspond to unbroken residual symmetries, are consistent with nonzero 13 mixing and deviations from maximal 2-3 mixing. For the simplest case, which leads to an S4 model and reproduces the allowed values of the mixing angles, we predict δ=(90°-120°).
Quark flavour observables in the Littlest Higgs model with T-parity after LHC Run 1
Energy Technology Data Exchange (ETDEWEB)
Blanke, Monika [CERN Theory Division, Geneva 23 (Switzerland); Karlsruhe Institute of Technology, Institut fuer Theoretische Teilchenphysik, Karlsruhe (Germany); Karlsruhe Institute of Technology, Institut fuer Kernphysik, Eggenstein-Leopoldshafen (Germany); Buras, Andrzej J. [TUM Institute for Advanced Study, Garching (Germany); Technische Universitaet Muenchen, Physik Department, Garching (Germany); Recksiegel, Stefan [Technische Universitaet Muenchen, Physik Department, Garching (Germany)
2016-04-15
The Littlest Higgs model with T-parity (LHT) belongs to the simplest new physics scenarios with new sources of flavour and CP violation. The latter originate in the interactions of ordinary quarks and leptons with heavy mirror quarks and leptons that are mediated by new heavy gauge bosons. Also a heavy fermionic top partner is present in this model which communicates with the SM fermions by means of standard W{sup ±} and Z{sup 0} gauge bosons. We present a new analysis of quark flavour observables in the LHT model in view of the oncoming flavour precision era. We use all available information on the CKM parameters, lattice QCD input and experimental data on quark flavour observables and corresponding theoretical calculations, taking into account new lower bounds on the symmetry breaking scale and the mirror quark masses from the LHC. We investigate by how much the branching ratios for a number of rare K and B decays are still allowed to depart from their SM values. This includes K{sup +} → π{sup +}ν anti ν, K{sub L} → π{sup 0}ν anti ν, K{sub L} → μ{sup +}μ{sup -}, B → X{sub s}γ, B{sub s,d} → μ{sup +}μ{sup -}, B → K{sup (*)}l{sup +}l{sup -}, B → K{sup (*)}ν anti ν, and ε{sup '}/ε. Taking into account the constraints from ΔF = 2 processes, significant departures from the SM predictions for K{sup +} → π{sup +}ν anti ν and K{sub L} → π{sup 0}ν anti ν are possible, while the effects in B decays are much smaller. In particular, the LHT model favours B(B{sub s} → μ{sup +}μ{sup -}) ≥ B(B{sub s} → μ{sup +}μ{sup -}){sub SM}, which is not supported by the data, and the present anomalies in B → K{sup (*)}l{sup +}l{sup -} decays cannot be explained in this model. With the recent lattice and large N input the imposition of the ε{sup '}/ε constraint implies a significant suppression of the branching ratio for K{sub L} → π{sup 0}ν anti ν with respect to its SM value while allowing only for small modifications of
Engels, W.J.M.
1997-01-01
Flavour is one of the most important attributes of cheese. Cheese flavour is the result of the breakdown of milk protein, fat, lactose and citrate due to enzymes from milk, rennet and microorganisms during production and ripening of cheese. For a large part the development of flavour during the ripe
Running of the SF-coupling with four massless flavours
International Nuclear Information System (INIS)
We discuss the status of different determinations of αs, motivating a precise and reliable computation from lattice QCD. In order to suppress perturbative errors, the non-perturbative computation has to reach high energy scales μ. Such results already exist in the SF-scheme for Nf=0;2 and Nf=3. We recently added the running with four massless flavours in a range of α from about 0.07 to 0.3. It is based on our recent determination of the Sheikholeslami Wohlert coefficient in the four-flavour theory. (orig.)
Theory of electric dipole moments and lepton flavour violation
Jung, Martin
2016-01-01
Electric dipole moments and charged-lepton flavour-violating processes are extremely sensitive probes for new physics, complementary to direct searches as well as flavour-changing processes in the quark sector. Beyond the "smoking-gun" feature of a potential significant measurement, however, it is crucial to understand their implications for new physics models quantitatively. The corresponding multi-scale problem of relating the existing high-precision measurements to fundamental parameters can be approached model-independently to a large extent; however, care must be taken to include the uncertainties from especially nuclear and QCD calculations properly.
Novel tomato flavours introduced by plastidial terpenoid pathway engineering.
Mollet, Beat; Niederberger, Peter; Pétiard, Vincent
2008-01-01
Until recently breeding efforts centred on high-yield production while sacrificing flavour and taste quality traits of mass produced food products, such as tomatoes. The recent publication of Davidovich-Rikanati et al. demonstrates the technical feasibility of the genetical engineering of pathways in tomato plants to modify their fruit flavour profile in a proof-of-concept approach. The reported work ranks among an increasing number of reported successful modifications of edible plants with a focus on the benefits to end-consumers.
Suppression of flavor violation in an A4 warped extra dimensional model
Kadosh, Avihay
2011-12-01
In an attempt to simultaneously explain the observed masses and mixing patterns of both quarks and leptons, we recently proposed a model (JHEP08(2010)115) based on the non abelian discrete flavor group A4, implemented in a custodial RS setup with a bulk Higgs. We showed that the standard model flavor structure can be realized within the zero mode approximation (ZMA), with nearly TBM neutrino mixing and a realistic CKM matrix with rather mild assumptions. An important advantage of this framework with respect to flavor anarchic models is the vanishing of the dangerous tree level KK gluon contribution to epsilonK and the suppression of the new physics one loop contributions to the neutron EDM, epsilon'/epsilon, b → Sγ and Higgs mediated flavor changing neutral curent (FCNC) processes. These results are obtained beyond the ZMA, in order to account for the the full flavor structure and mixing of the zero modes and first Kaluza-Klein (KK) modes of all generations. The resulting constraints on the KK mass scale are shown to be significantly relaxed compared to the flavour anarchic case, showing explicitly the role of non abelian discrete flavor symmetries in relaxing flavor violation bounds within the RS setup. As a byproduct of our analysis we also obtain the same contributions for the custodial anarchic case with two SU(2)R doublets for each fermion generation.
DEFF Research Database (Denmark)
Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister;
is not considered sufficient to evaluate chronic effects of the substance. Accordingly, additional data are required for the candidate substance. According to the practice of the Panel, a minimum requirement to provide an adequate NOAEL for flavourings in the Procedure is a 90-day study. In order to determine......The Scientific Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (the Panel) was asked to provide scientific advice to the Commission on the implications for human health of chemically defined flavouring substances used in or on foodstuffs in the Member States. In particular...... of the flavouring substances in Europe. However, when the Panel examined the information provided by the European Flavouring Industry on the use levels in various foods, it appeared obvious that the MSDI approach in a number of cases would grossly underestimate the intake by regular consumers of products flavoured...
Marchis, Iuliana
2009-01-01
Symmetry is one of the fundamental concepts in Geometry. It is a Mathematical concept, which can be very well connected with Art and Ethnography. The aim of the article is to show how to link the geometrical concept symmetry with interculturality. For this mosaics from different countries are used.
2016-01-01
The Symmetry Festival is a science and art program series, the most important periodic event (see its history) to bring together scientists, artists, educators and practitioners interested in symmetry (its roots, what is behind, applications, etc.), or in the consequences of its absence.
Symmetry in Mathematics Learning.
Dreyfus, Tommy; Eisenberg, Theodore
1989-01-01
Discusses the creed in symmetry and the omnipresence of symmetrical relationships in mathematics and nature, discusses mathematicians' attraction toward looking for symmetrical relationships as an unstated problem-solving heuristic, and shows how symmetry can be used as a didactical tool. (Author/MKR)
Symmetry relation for helical plasmas: parity symmetry
International Nuclear Information System (INIS)
It is shown that a symmetry relation holds strictly in the LHD (Large Helical Device) type helical magnetic fields. The symmetry relation can be expressed explicitly in the rotating helical coordinate system. It is named as parity symmetry in helical systems. A new concept, - concept of even scalars, odd scalars, even vectors, odd vectors -, is introduced. Calculus of vector operation retains strictly the parity relations for these quantities. For example, the vector product of two vectors with same parity become a odd parity vector. The rotation of a vector field A, ∇ x A, has same parity characteristics with the vector A. It is concluded that the equilibrium magnetic field and current distribution are expressed by even parity vectors. Pressure distribution is expressed by an even parity scalar function. The parity symmetry relations conduct uniquely the power expansion form of equilibrium magnetic field and pressure distribution. Analytical expression for these quantities are obtained approximately by truncation of the power series. Closed magnetic surface, islands, chaotic field line region and divertor field lines are well reproduced by this simple model. (author)
The neutrino mass matrix and (selected) variants of A4
Indian Academy of Sciences (India)
Martin Hirsch
2009-01-01
Recent neutrino oscillation experiments have measured leptonic mixing angles with considerable precision. Many theoretical attempts to understand the peculiar mixing structure, observed in these measurements, are based on non-Abelian flavour symmetries. This talk concentrates exclusively on models based on the non-Abelian symmetry 4 . 4 is particularly well suited to describe three family mixing, and allows to explain the near tri-bimaximal mixing observed. Special emphasis is put here on the discussion of the neutrinoless double beta decay observable $\\langle m_{} \\rangle$ . Different models based on 4 with very similar predictions for neutrino angles can yield vastly different expectations for $\\langle m_{} \\rangle$ . Neutrinoless double beta decay can thus serve, in principle, as a discriminator between different neutrino mass models.
Symmetry Effects in Computation
Yao, Andrew Chi-Chih
2008-12-01
The concept of symmetry has played a key role in the development of modern physics. For example, using symmetry, C.N. Yang and other physicists have greatly advanced our understanding of the fundamental laws of physics. Meanwhile, computer scientists have been pondering why some computational problems seem intractable, while others are easy. Just as in physics, the laws of computation sometimes can only be inferred indirectly by considerations of general principles such as symmetry. The symmetry properties of a function can indeed have a profound effect on how fast the function can be computed. In this talk, we present several elegant and surprising discoveries along this line, made by computer scientists using symmetry as their primary tool. Note from Publisher: This article contains the abstract only.
Loebbert, Florian
2016-01-01
In these introductory lectures we discuss the topic of Yangian symmetry from various perspectives. Forming the classical counterpart of the Yangian and an extension of ordinary Noether symmetries, first the concept of nonlocal charges in classical, two-dimensional field theory is reviewed. We then define the Yangian algebra following Drinfeld's original motivation to construct solutions to the quantum Yang-Baxter equation. Different realizations of the Yangian and its mathematical role as a Hopf algebra and quantum group are discussed. We demonstrate how the Yangian algebra is implemented in quantum, two-dimensional field theories and how its generators are renormalized. Implications of Yangian symmetry on the two-dimensional scattering matrix are investigated. We furthermore consider the important case of discrete Yangian symmetry realized on integrable spin chains. Finally we give a brief introduction to Yangian symmetry in planar, four-dimensional super Yang-Mills theory and indicate its impact on the dila...
Partial Dynamical Symmetry as an Intermediate Symmetry Structure
Leviatan, A
2003-01-01
We introduce the notion of a partial dynamical symmetry for which a prescribed symmetry is neither exact nor completely broken. We survey the different types of partial dynamical symmetries and present empirical examples in each category.
Perinatal flavour learning and adaptation to being weaned: all the pig needs is smell.
Directory of Open Access Journals (Sweden)
Marije Oostindjer
Full Text Available Perinatal flavour learning through the maternal diet is known to enhance flavour preference and acceptance of flavoured food in many species, yet still little is known about the mechanism underlying perinatal flavour learning. Previously we found positive effects of perinatal flavour learning on food intake, growth and behaviour of piglets postweaning, but no increased preference for the flavour. This suggests that flavour learning in pigs works through a reduction of weaning stress by the presence of the familiar flavour instead. The aim of this study was to investigate whether perinatal flavour learning reduces stress at weaning, and whether the effect is stronger when the familiar flavour is present in the food. Sows were offered an anethol-flavoured diet (Flavour treatment or control diet (Control treatment during late gestation and lactation. Flavour and Control piglets were provided with anethol either in their food (Food treatment or in the air (Air treatment after weaning. Preweaning and postweaning treatments did not affect food intake, preference or growth in the first two weeks postweaning but flavour treatment reduced the latency to eat (24 versus 35 hours, P = 0.02 and within-pen variation in growth (SD within-pen: 0.7 versus 1.2 kg, P<0.001. Salivary cortisol levels tended to be lower four and seven hours postweaning for Flavour piglets compared to Control piglets (4 hours: 2.5 versus 3.0 ng/ml, P = 0.05, 7 hours: 3.1 versus 3.4 ng/ml, P = 0.08. Flavour piglets played more and showed less damaging behaviours than Control piglets, indicating that the familiar flavour reduced stress around weaning. Few interaction effects were found between preweaning and postweaning treatment, and no effects of postweaning treatment. We conclude that in the newly weaned pig, perinatal flavour learning results in a reduction of stress when the familiar flavour is present, regardless of providing the flavour in the food or in the air.
Grand Unified Theories and Lepton-Flavour Violation
Lim, C S
1998-01-01
Lepton-flavour violating processes, such as $\\mu \\to e\\gamma$, are studied in ordinary (non-SUSY) SU(5) and SUSY SU(5) grand unified theories. First given are some introductory argument on the mechanism of U.V. divergence cancellation in flavour changing neutral current processes and on the decoupling of particles with GUT scale masses . We next see that such general argument is confirmed by an explicit calculation of the amplitude of $\\mu \\to e\\gamma$ in ordinary SU(5), which shows that logarithmic divergence really cancels among diagrams and remaining finite part are suppressed by at least $1/M_{GUT}^2$. In SUSY SU(5), flavour changing slepton mass-squared term get a logarithmic correction, as recently claimed. However, when the effect of flavour changing wave function renormalization is also taken into account such logarithmic correction turns out to disappear, provided a condition is met among SUSY breaking soft masses. In SUGRA-inspired SUSY GUT, such condition is not satisfied. But the remaining logarit...
New physics search with flavour in the LHC era
Hurth, Tobias
2013-01-01
We give a status report on quark flavour physics in view of the latest data from the B factories and the LHC, and discuss the impact of the latest experimental results on new physics in the MFV framework. We also show some examples of the implications in supersymmetry.
Effect of tomato pleiotropic ripening mutations on flavour volatile biosynthesis
Kovacs, K.; Fray, R.G.; Tikunov, Y.M.; Graham, N.; Bradley, G.; Seymour, G.B.; Bovy, A.G.; Grierson, D.
2009-01-01
Ripening is a tightly controlled and developmentally regulated process involving networks of genes, and metabolites that result in dramatic changes in fruit colour, texture and flavour. Molecular and genetic analysis in tomato has revealed a series of regulatory genes involved in fruit development a
A taste of dark matter: flavour constraints on pseudoscalar mediators
M.J. Dolan; F. Kahlhoefer; C. McCabe; K. Schmidt-Hoberg
2015-01-01
Dark matter interacting via the exchange of a light pseudoscalar can induce observable signals in indirect detection experiments and experience large self-interactions while evading the strong bounds from direct dark matter searches. The pseudoscalar mediator will however induce flavour-changing int
Formation of Amino Acid Derived Cheese Flavour Compounds
Smit, B.A.
2004-01-01
Lactic acid bacteria (LAB), among them Lactococcus lactis, are often used for the fermentation of milk into various products, such as cheeses. For their growth and maintenance LAB metabolise milk sugar, protein and fat into various low molecular compounds, which sometimes have strong flavour charact
LHCb results on flavour physics and implications to BSM
Langenbruch, C
2014-01-01
LHCb is a dedicated flavour physics experiment at the LHC. Precision measurements of CP violation and the study of rare decays of hadrons containing beauty and charm quarks constitute powerful searches for New Physics. A selection of recent LHCb results and their implications to physics beyond the Standard Model are discussed.
LHCb results on flavour physics and implications to BSM
International Nuclear Information System (INIS)
LHCb is a dedicated flavour physics experiment at the LHC. Precision measurements of CP violation and the study of rare decays of hadrons containing beauty and charm quarks constitute powerful searches for New Physics. A selection of recent LHCb results and their implications to physics beyond the Standard Model are discussed.
Supersymmetry, the flavour puzzle and rare B decays
Energy Technology Data Exchange (ETDEWEB)
Straub, David Michael
2010-07-14
The gauge hierarchy problem and the flavour puzzle belong to the most pressing open questions in the Standard Model of particle physics. Supersymmetry is arguably the most popular framework of physics beyond the Standard Model and provides an elegant solution to the gauge hierarchy problem; however, it aggravates the flavour puzzle. In the first part of this thesis, I discuss several approaches to address the flavour puzzle in the minimal supersymmetric extension of the Standard Model and experimental tests thereof: supersymmetric grand unified theories with a unification of Yukawa couplings at high energies, theories with minimal flavour violation and additional sources of CP violation and theories with gauge mediation of supersymmetry breaking and a large ratio of Higgs vacuum expectation values. In the second part of the thesis, I discuss the phenomenology of two rare B meson decay modes which are promising probes of physics beyond the Standard Model: The exclusive B {yields} K{sup *}l{sup +}l{sup -} decay, whose angular decay distribution will be studied at LHC and gives access to a large number of observables and the b{yields}s{nu}anti {nu} decays, which are in the focus of planned high-luminosity Super B factories. I discuss the predictions for these observables in the Standard Model and their sensitivity to New Physics. (orig.)
The flavour of supersymmetry: Phenomenological implications of sfermion mixing
Arana-Catania, M
2013-01-01
We study the phenomenological implications of sfermion flavour mixing in supersymmetry in the context of Non-Minimal Flavour Violation (NMFV). We study the general flavour mixing hypothesis, parametrizing the squark and slepton mass matrices by a complete set of delta^XY_ij (X,Y=L,R; i,j= t,c,u or b,s,d for squarks/1,2,3 for sleptons). With respect to the squark sector, we study the behaviour of the B-physics observables BR(B -> Xs gamma), BR(Bs -> mu+ mu-) and delta M_B_s and update the constraints to the delta parameters coming from them. We present one-loop corrections to the Higgs boson masses in the MSSM with NMFV in the squark sector, and taking into account the previous constraints we evaluate them, finding sizable corrections, exceeding sometimes tens of GeV for the light Higgs boson. These corrections might be used to set further constraints on the delta parameters from the Higgs boson mass measurement. With respect to the slepton sector, we explore the implications on charged lepton flavour violatin...
Effects of flavour absorption on foods and their packaging materials
Willige, van R.W.G.
2002-01-01
Keywords: flavour absorption, scalping, packaging, food matrix, lldpe, ldpe, pp, pc, pet, pen,b-lactoglobulin, casein, pectin, cmc, lactose, saccharose, oil, modelling, storage, oxygen permeability, taste perception, sensory quality.Abso
Heavy Flavour Production at the electron-proton collider HERA
Urban, Klaus
2009-01-01
An overview over the recent heavy flavour results of the H1 and ZEUS collaborations is presented. Various techniques to tag the heavy quark, which allow to explore different phase space regions, are employed. Predictions of pertubative QCD are compared to the charm and beauty production data. Charm and beauty fractions of the proton structure function $F_2$ are
Selected results on heavy flavour physics at LHCb
Charles, Matthew
Selected results from the LHCb experiment in the domain of heavy flavour particle physics are presented. These results are split into two groups: the first concerns searches for new physics in the decays of charmed hadrons, and the second consists of studies of the spectroscopy of baryons.
LHCb : Search for Lepton Flavour Violation at LHCb
Rives Molina, Vicente
2014-01-01
The observation of neutrino oscillations has re-opened the case for searches of lepton-flavour violating decays. We report on recent results on searches for short or long-lived Majorana heavy neutrinos in B&arr;μμπ and τ→μμμ decays
Leviatan, A
2010-01-01
This overview focuses on the notion of partial dynamical symmetry (PDS), for which a prescribed symmetry is obeyed by a subset of solvable eigenstates, but is not shared by the Hamiltonian. General algorithms are presented to identify interactions, of a given order, with such intermediate-symmetry structure. Explicit bosonic and fermionic Hamiltonians with PDS are constructed in the framework of models based on spectrum generating algebras. PDSs of various types are shown to be relevant to nuclear spectroscopy, quantum phase transitions and systems with mixed chaotic and regular dynamics.
Schwichtenberg, Jakob
2015-01-01
This is a textbook that derives the fundamental theories of physics from symmetry. It starts by introducing, in a completely self-contained way, all mathematical tools needed to use symmetry ideas in physics. Thereafter, these tools are put into action and by using symmetry constraints, the fundamental equations of Quantum Mechanics, Quantum Field Theory, Electromagnetism, and Classical Mechanics are derived. As a result, the reader is able to understand the basic assumptions behind, and the connections between the modern theories of physics. The book concludes with first applications of the previously derived equations.
Symmetry in Boolean Satisfiability
Directory of Open Access Journals (Sweden)
Fadi A. Aloul
2010-06-01
Full Text Available This paper reviews recent approaches on how to accelerate Boolean Satisfiability (SAT search by exploiting symmetries in the problem space. SAT search algorithms traverse an exponentially large search space looking for an assignment that satisfies a set of constraints. The presence of symmetries in the search space induces equivalence classes on the set of truth assignments. The goal is to use symmetries to avoid traversing all assignments by constraining the search to visit a few representative assignments in each equivalence class. This can lead to a significant reduction in search runtime without affecting the completeness of the search.
Sequential flavor symmetry breaking
International Nuclear Information System (INIS)
The gauge sector of the standard model exhibits a flavor symmetry that allows for independent unitary transformations of the fermion multiplets. In the standard model the flavor symmetry is broken by the Yukawa couplings to the Higgs boson, and the resulting fermion masses and mixing angles show a pronounced hierarchy. In this work we connect the observed hierarchy to a sequence of intermediate effective theories, where the flavor symmetries are broken in a stepwise fashion by vacuum expectation values of suitably constructed spurion fields. We identify the possible scenarios in the quark sector and discuss some implications of this approach.
Low-energy pi-pi and pi-K scatterings revisited in three-flavour resummed chiral perturbation theory
Descotes-Genon, S
2007-01-01
Chiral symmetry breaking may exhibit significantly different patterns in two chiral limits: N_f=2 massless flavours (m_u=m_d=0, m_s physical) and N_f=3 massless flavours (m_u=m_d=0=m_s=0). Such a difference may arise due to vacuum fluctuations of s-bar{s} pairs related to the violation of the Zweig rule in the scalar sector, and could yield a numerical competition between contributions counted as leading order and next-to-leading in the chiral expansions of observables. We recall and extend Resummed Chiral Perturbation Theory (ReChPT), a framework that we introduced previously to deal with such instabilities: it requires a more careful definition of the relevant observables and their one-loop chiral expansions. We analyse the amplitudes for low-energy pi-pi and pi-K scatterings within ReChPT, which we match in subthreshold regions with dispersive representations obtained from the solutions Roy and Roy-Steiner equations. Using a frequentist approach, we constrain the quark mass ratio as well as the quark conde...
Symmetry relation for helical plasma. Parity symmetry
International Nuclear Information System (INIS)
It is shown that a strict symmetry relation holds in the LHD (Large Helical Device) type helical magnetic field. The symmetry relation is expressed explicitly in the rotating helical coordinate system and named as parity symmetry in helical system. A new concept, -concept of even scalars, odd scalars, even vectors, odd vectors-, is introduced. Calculus of vector operation retains strictly the parity relations for these quantities. For example, the vector product of two vectors with same parity become an odd parity vector. The rotation of a vector field A, ∇xA, has same parity characteristics with that of the vector A. It is concluded that the equilibrium magnetic field and current distribution are expressed by even parity vectors. Pressure distribution is expressed by an even parity scalar function. The parity symmetry relations conduct uniquely the power expansion form of equilibrium magnetic field and pressure distribution. Analytical expressions for these quantities are obtained approximately by truncation of the power series. An example of vacuum helical magnetic field is shown in the following, B=∇xA+B0(0, 0, r0/r), A=Bp/a=-(p/3r)Y3-(p3/12r3)Y(X4+Y4), -(p/3r)X3-(p3/12r3)X(X4+Y4), -((X2-Y2)/2)(1-(Xcos(pφ)-Ysin(pφ))/4r)-(p4/6r4)X2Y2)=, where p, r0, a, Bp, B0 are constants for magnetic field. Rotating helical coordinate system is expressed by (X, Y, φ) and r≡r0+Xcos (pφ) - Ysin (pφ). Closed magnetic surface, islands, chaotic field line region and divertor field lines are well represented by this simple model. (author)
Reduction of $SU_f(3)\\supset SO(3)\\supset A_4$-The scalar potential
,
2016-01-01
We examine the possibility of the flavor symmetry being $SU_f(3)$ in which the phenomenologically successful discreet symmetry $A_4$ is embedded. The allowed quadratic and quartic potentials are constructed exploiting the full symmetry chain $SU(3)\\supset SO(4)\\supset A_4$. The special case of the $SU(3)$ decaplet and octet scalar fields is analyzed.
Heavy flavour production and heavy flavour mixing at the CERN proton-antiproton collider
International Nuclear Information System (INIS)
In this thesis some results of the proton-antiproton-collision experiment UA1 with the CERN Super Proton-Antiproton Synchrotron are presented and interpreted. Ch. 1 contians a general introduction to the physics motivations behind the proton-antiproton-collider project, a brief description of the CERN facilities and a summary of collider and UA1 physics achievements. Furthermore the concept of studying heavy flavours via their weak decays into muons is introduced. Ch. 2 gives a brief overview of the UA1 experimental set-up, while those parts of the detector that are relevant for the analysis, presented in this thesis, is discussed in some more detail. Ch. 3 contains a short introduction to, and motivation for the use of Monte Carlo techniques in event simulations, while Ch. 4 describes the framework of the recently developed 'EUROJET' event generator. In Ch. 5 a treatment is given of the theoretical background and concepts like 'quark-mixing' and 'CP-violation' are explained, also other useful definitions and formulae are introduced on which the later analysis of the same-sign to opposite-sign dimuon ratio is built. Data collection and event reconstruction is the subject of Ch. 6, while a detailed comparison between the theoretical models and experimentally obtained distributions is given in Ch. 7. Finally, in Ch. 8 some concluding remarks are made. 182 refs.; 81 figs.; 9 tabs
Golubitsky, Martin
2012-04-01
Many gaits of four-legged animals are described by symmetry. For example, when a horse paces it moves both left legs in unison and then both right legs and so on. The motion is described by two symmetries: Interchange front and back legs, and swap left and right legs with a half-period phase shift. Biologists postulate the existence of a central pattern generator (CPG) in the neuronal system that sends periodic signals to the legs. CPGs can be thought of as electrical circuits that produce periodic signals and can be modeled by systems with symmetry. In this lecture we discuss animal gaits; use gait symmetries to construct a simplest CPG architecture that naturally produces quadrupedal gait rhythms; and make several testable predictions about gaits.
Lovelady, Benjamin C.; Wheeler, James T.
2016-04-01
According to the Coleman-Mandula theorem, any gauge theory of gravity combined with an internal symmetry based on a Lie group must take the form of a direct product in order to be consistent with basic assumptions of quantum field theory. However, we show that an alternative gauging of a simple group can lead dynamically to a spacetime with compact internal symmetry. The biconformal gauging of the conformal symmetry of n-dimensional Euclidean space doubles the dimension to give a symplectic manifold. Examining one of the Lagrangian submanifolds in the flat case, we find that in addition to the expected S O (n ) connection and curvature, the solder form necessarily becomes Lorentzian. General coordinate invariance gives rise to an S O (n -1 ,1 ) connection on the spacetime. The principal fiber bundle character of the original S O (n ) guarantees that the two symmetries enter as a direct product, in agreement with the Coleman-Mandula theorem.
International Nuclear Information System (INIS)
In the present work, we elucidate the meaning of the custodial symmetry and its importance at the phenomenological level in the framework of the standard model of the electroweak interactions and its possible extensions. (Author)
International Nuclear Information System (INIS)
The purpose of this course is to study the evolution of the symmetry concept and establish its influence in the knowledge of the fundamental laws of nature. Physicist have been using the symmetry concept in two ways: to solve problems and to search for new understanding of the world around us. In quantum physics symmetry plays a key role in gaining an understanding of the physical laws governing the behavior of matter and field systems. It provides, generally, a shortcut based on geometry for discovering the secrets of the Universe. Because it is believed that the laws of physics are invariant under discrete and continuous transformation operations of the space and time, there are continuous symmetries, for example, energy and momentum together with discrete ones corresponding to charge, parity and time reversal operations.
Global Bifurcations With Symmetry
Porter, J B
2001-01-01
Symmetry is a ubiquitous feature of physical systems with profound implications for their dynamics. This thesis investigates the role of symmetry in global bifurcations. In particular, the structure imposed by symmetry can encourage the formation of complex solutions such as heteroclinic cycles and chaotic invariant sets. The first study focuses on the dynamics of 1:n steady-state mode interactions in the presence of O(2) symmetry. The normal form equations considered are relevant to a variety of physical problems including Rayleigh-Bénard convection with periodic boundary conditions. In open regions of parameter space these equations contain structurally stable heteroclinic cycles composed of connections between standing wave, pure mode, and trivial solutions. These structurally stable cycles exist between two global bifurcations, the second of which involves an additional mixed mode state and creates as many as four distinct kinds of structurally unstable heteroclinic cycles. The various cycles c...
Lovelady, Benjamin C
2015-01-01
According to the Coleman-Mandula theorem, any gauge theory of gravity combined with an internal symmetry based on a Lie group must take the form of a direct product in order to be consistent with basic assumptions of quantum field theory. However, we show that an alternative gauging of a simple group can lead dynamically to a spacetime with compact internal symmetry. The biconformal gauging of the conformal symmetry of n-dim Euclidean space doubles the dimension to give a symplectic manifold. Examining one of the Lagrangian submanifolds in the flat case, we find that in addition to the expected SO(n) connection and curvature, the solder form necessarily becomes Lorentzian. General coordinate invariance gives rise to an SO(n-1,1) connection on the spacetime. The principal fiber bundle character of the original SO(n) guarantees that the two symmetries enter as a direct product, in agreement with the Coleman-Mandula theorem.
Gauge symmetry from decoupling
Wetterich, C
2016-01-01
Gauge symmetries emerge from a redundant description of the effective action for light degrees of freedom after the decoupling of heavy modes. This redundant description avoids the use of explicit constraints in configuration space. For non-linear constraints the gauge symmetries are non-linear. In a quantum field theory setting the gauge symmetries are local and can describe Yang-Mills theories or quantum gravity. We formulate gauge invariant fields that correspond to the non-linear light degrees of freedom. In the context of functional renormalization gauge symmetries can emerge if the flow generates or preserves large mass-like terms for the heavy degrees of freedom. They correspond to a particular form of gauge fixing terms in quantum field theories.
Second order symmetry operators
Andersson, Lars; Blue, Pieter
2014-01-01
Using systematic calculations in spinor language, we obtain simple descriptions of the second order symmetry operators for the conformal wave equation, the Dirac-Weyl equation and the Maxwell equation on a curved four dimensional Lorentzian manifold. The conditions for existence of symmetry operators for the different equations are seen to be related. Computer algebra tools have been developed and used to systematically reduce the equations to a form which allows geometrical interpretation.
Energy Technology Data Exchange (ETDEWEB)
Blum, Alexander Simon
2009-06-10
This thesis deals with the possibility of describing the flavor sector of the Standard Model of Particle Physics (with neutrino masses), that is the fermion masses and mixing matrices, with a discrete, non-abelian flavor symmetry. In particular, mass independent textures are considered, where one or several of the mixing angles are determined by group theory alone and are independent of the fermion masses. To this end a systematic analysis of a large class of discrete symmetries, the dihedral groups, is analyzed. Mass independent textures originating from such symmetries are described and it is shown that such structures arise naturally from the minimization of scalar potentials, where the scalars are gauge singlet flavons transforming non-trivially only under the flavor group. Two models are constructed from this input, one describing leptons, based on the group D{sub 4}, the other describing quarks and employing the symmetry D{sub 14}. In the latter model it is the quark mixing matrix element V{sub ud} - basically the Cabibbo angle - which is at leading order predicted from group theory. Finally, discrete flavor groups are discussed as subgroups of a continuous gauge symmetry and it is shown that this implies that the original gauge symmetry is broken by fairly large representations. (orig.)
International Nuclear Information System (INIS)
This thesis deals with the possibility of describing the flavor sector of the Standard Model of Particle Physics (with neutrino masses), that is the fermion masses and mixing matrices, with a discrete, non-abelian flavor symmetry. In particular, mass independent textures are considered, where one or several of the mixing angles are determined by group theory alone and are independent of the fermion masses. To this end a systematic analysis of a large class of discrete symmetries, the dihedral groups, is analyzed. Mass independent textures originating from such symmetries are described and it is shown that such structures arise naturally from the minimization of scalar potentials, where the scalars are gauge singlet flavons transforming non-trivially only under the flavor group. Two models are constructed from this input, one describing leptons, based on the group D4, the other describing quarks and employing the symmetry D14. In the latter model it is the quark mixing matrix element Vud - basically the Cabibbo angle - which is at leading order predicted from group theory. Finally, discrete flavor groups are discussed as subgroups of a continuous gauge symmetry and it is shown that this implies that the original gauge symmetry is broken by fairly large representations. (orig.)
Cherry-flavoured electronic cigarettes expose users to the inhalation irritant, benzaldehyde.
Kosmider, Leon; Sobczak, Andrzej; Prokopowicz, Adam; Kurek, Jolanta; Zaciera, Marzena; Knysak, Jakub; Smith, Danielle; Goniewicz, Maciej L
2016-04-01
Many non-cigarette tobacco products, including e-cigarettes, contain various flavourings, such as fruit flavours. Although many flavourings used in e-cigarettes are generally recognised as safe when used in food products, concerns have been raised about the potential inhalation toxicity of these chemicals. Benzaldehyde, which is a key ingredient in natural fruit flavours, has been shown to cause irritation of respiratory airways in animal and occupational exposure studies. Given the potential inhalation toxicity of this compound, we measured benzaldehyde in aerosol generated in a laboratory setting from flavoured e-cigarettes purchased online and detected benzaldehyde in 108 out of 145 products. The highest levels of benzaldehyde were detected in cherry-flavoured products. The benzaldehyde doses inhaled with 30 puffs from flavoured e-cigarettes were often higher than doses inhaled from a conventional cigarette. Levels in cherry-flavoured products were >1000 times lower than doses inhaled in the workplace. While e-cigarettes seem to be a promising harm reduction tool for smokers, findings indicate that using these products could result in repeated inhalation of benzaldehyde, with long-term users risking regular exposure to the substance. Given the uncertainty surrounding adverse health effects stemming from long-term inhalation of flavouring ingredients such as benzaldehyde, clinicians need to be aware of this emerging risk and ask their patients about use of flavoured e-cigarettes.
DEFF Research Database (Denmark)
Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister;
The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate sodium diacetate [FL-no: 16.073] in the Flavouring Group Evaluation 309, using the Procedure in Commission Regulation (EC) No 1565/2000. However, although...
DEFF Research Database (Denmark)
Beltoft, Vibe Meister; Binderup, Mona-Lise; Frandsen, Henrik Lauritz;
and agrees with the JECFA conclusion, “No safety concern at estimated levels of intake as flavouring substances” based on the MSDI approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered and for all five substances...
DEFF Research Database (Denmark)
Beltoft, Vibe Meister; Binderup, Mona-Lise; Frandsen, Henrik Lauritz;
as flavouring substances, as these substances could not be evaluated because of concern with respect to genotoxicity. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered and for all 26 substances, the information is adequate....
Kawamura, Yoshiharu
2015-01-01
We study the quantization of systems with local particle-ghost symmetries. The systems contain ordinary particles including gauge bosons and their counterparts obeying different statistics. The particle-ghost symmetry is a kind of fermionic symmetry, different from the space-time supersymmetry and the BRST symmetry. Subsidiary conditions on states guarantee the unitarity of systems.
Green tea flavour determinants and their changes over manufacturing processes.
Han, Zhuo-Xiao; Rana, Mohammad M; Liu, Guo-Feng; Gao, Ming-Jun; Li, Da-Xiang; Wu, Fu-Guang; Li, Xin-Bao; Wan, Xiao-Chun; Wei, Shu
2016-12-01
Flavour determinants in tea infusions and their changes during manufacturing processes were studied using Camellia sinensis cultivars 'Bai-Sang Cha' ('BAS') possessing significant floral scents and 'Fuding-Dabai Cha' ('FUD') with common green tea odour. Metabolite profiling based on odour activity threshold revealed that 'BAS' contained higher levels of the active odorants β-ionone, linalool and its two oxides, geraniol, epoxylinalool, decanal and taste determinant catechins than 'FUD' (pmanufacturing processes, the levels of linalool and geraniol decreased whereas those of β-ionone, linalool oxides, indole and cis-jasmone increased. Compared with pan-fire treatment, steam treatment reduced the levels of catechins and proportion of geraniol, linalool and its derivatives, consequently, reducing catechin-related astringency and monoterpenol-related floral scent. Our study suggests that flavour determinant targeted modulation could be made through genotype and manufacturing improvements. PMID:27374591
Oxidative flavour deterioration of fish oil enriched milk
DEFF Research Database (Denmark)
Bruni Let, Mette; Jacobsen, Charlotte; Frankel, E.N.;
2003-01-01
The oxidative deterioration of milk emulsions supplemented with 1.5 wt-% fish oil was investigated by sensory evaluation and by determining the peroxide value and volatile oxidation products after cold storage. Two types of milk emulsions were produced, one with a highly unsaturated tuna oil (38 wt...... emulsions, indicating that metal chelation with EDTA could inhibit the decomposition of lipid hydroperoxides in these emulsions. This study showed that an oxidatively stable milk emulsion containing highly polyunsaturated tuna fish oil could be prepared without significant fishy off-flavour development upon...... than the tuna oil emulsions, having a lower initial peroxide value (0.1 meq/kg). In the tuna oil emulsions the fishy off-flavour could not be detected throughout the storage period. Addition of 5-50 ppm EDTA significantly reduced the development of volatile oxidation products in the cod liver oil...
New Aspects of Flavour Model Building in Supersymmetric Grand Unification
Spinrath, Martin
2010-01-01
We derive predictions for Yukawa coupling ratios within GUTs generated from operators with mass dimension four and five. These relations are a characteristic property of unified flavour models and can reduce the large number of free parameters related to the flavour sector of the SM. The Yukawa couplings of the down-type quarks and charged leptons are affected within SUSY models by tan beta-enhanced threshold corrections. We analyse these corrections and give simple analytic expressions and numerical estimates for them. The threshold corrections sensitively depend on the soft SUSY breaking parameters. Especially, they determine if the affected Yukawa couplings are enhanced or suppressed. In a first approach, we make some plausible assumptions about the soft SUSY parameters. In a second, more sophisticated approach we use three common breaking schemes in which all the soft breaking parameters at the electroweak scale can be calculated from only a handful of parameters. Within this approach, we apply various ph...
Green tea flavour determinants and their changes over manufacturing processes.
Han, Zhuo-Xiao; Rana, Mohammad M; Liu, Guo-Feng; Gao, Ming-Jun; Li, Da-Xiang; Wu, Fu-Guang; Li, Xin-Bao; Wan, Xiao-Chun; Wei, Shu
2016-12-01
Flavour determinants in tea infusions and their changes during manufacturing processes were studied using Camellia sinensis cultivars 'Bai-Sang Cha' ('BAS') possessing significant floral scents and 'Fuding-Dabai Cha' ('FUD') with common green tea odour. Metabolite profiling based on odour activity threshold revealed that 'BAS' contained higher levels of the active odorants β-ionone, linalool and its two oxides, geraniol, epoxylinalool, decanal and taste determinant catechins than 'FUD' (psteam treatment reduced the levels of catechins and proportion of geraniol, linalool and its derivatives, consequently, reducing catechin-related astringency and monoterpenol-related floral scent. Our study suggests that flavour determinant targeted modulation could be made through genotype and manufacturing improvements.
Lepton Flavour Violating Higgs Decays in the (SUSY) Inverse Seesaw
Arganda, E; Marcano, X; Weiland, C
2016-01-01
The observation of charged lepton flavour violation would be a smoking gun for new physics and could help in pinpointing the mechanism at the origin of neutrino masses and mixing. We present here our recent studies of lepton flavour violating Higgs decays in the inverse seesaw and its supersymmetric embedding, two examples of low-scale seesaw mechanisms. We predict branching ratios as large as $10^{-5}$ for the decays $h\\rightarrow \\tau \\mu$ and $h \\rightarrow \\tau e$ in the inverse seesaw, which can be probed in future colliders. Supersymmetric contributions can enhance the branching ratio of $h\\rightarrow \\tau \\mu$ up to $1\\%$, making it large enough to explain the small excess observed by ATLAS and CMS.
Heavy Flavour Cascade Production in a Beam Dump
2015-01-01
SHiP will use a 400~GeV/c proton beam impinging on a several interaction length long Molybdenum target. Heavy flavour hadrons produced in the dump can decay semi-leptonically, which can produce both the Heavy Neutral Leptons as signal, but also potential background from muons and neutrinos. The absolute rate of heavy flavour production is taken from measurements. Pythia is used to predict the phase space distribution of the charm and beauty hadrons which are produced both in the primary interaction of the 400~GeV/c proton and in interactions of the secondaries produced in the cascade. The full cascade production of both HNL and background is compared to that reported in the SHiP Technical Proposal, where only the primary $pN$ interactions were taken into account.
Comparison of flavour qualities of three sourced Eriocheir sinensis.
Wang, Shuai; He, Yu; Wang, Yayue; Tao, Ningping; Wu, Xugan; Wang, Xichang; Qiu, Weiqiang; Ma, Mingjun
2016-06-01
Flavour qualities of three edible parts of three types of Chinese mitten crab from different areas were examined. The flavour profiles detected by E-tongue and E-nose showed that differences existed in tastes and odours among wild-caught crabs (WC), Yangcheng crabs (YC) and Chongming crabs (CM). The total free amino acids contents of WC were all at the highest level in meat, gonads and hepatopancreas. Ovaries had the highest nucleotides content and equivalent umami concentration (EUC) than other tissues in both female and male. The EUC was the highest in all parts of WC, followed by YC and CM. The total content of nine key volatile compounds was the highest for WC in the gonads and hepatopancreas; in the muscle, they were the highest in female YC and male CM, but the lowest for WC. PMID:26830556
$B$ flavour tagging using charm decays at the LHCb experiment
Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; d'Argent, Philippe; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Bellee, Violaine; Belloli, Nicoletta; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Billoir, Pierre; Bird, Thomas; Birnkraut, Alex; Bizzeti, Andrea; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Buchanan, Emma; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cavallero, Giovanni; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dall'Occo, Elena; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Demmer, Moritz; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Di Ruscio, Francesco; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fohl, Klaus; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Gazzoni, Giulio; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Girard, Olivier Göran; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadavizadeh, Thomas; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Humair, Thibaud; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kecke, Matthieu; Kelsey, Matthew; Kenyon, Ian; Kenzie, Matthew; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Kozeiha, Mohamad; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Krzemien, Wojciech; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kuonen, Axel Kevin; Kurek, Krzysztof; Kvaratskheliya, Tengiz; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Liu, Xuesong; Loh, David; Longstaff, Iain; Lopes, Jose; Lucchesi, Donatella; Lucio Martinez, Miriam; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Lusiani, Alberto; Machefert, Frederic; Maciuc, Florin; Maev, Oleg; Maguire, Kevin; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Marks, Jörg; Martellotti, Giuseppe; Martin, Morgan; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; Meadows, Brian; Meier, Frank; Meissner, Marco; Melnychuk, Dmytro; Merk, Marcel; Michielin, Emanuele; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Molina Rodriguez, Josue; Monroy, Igancio Alberto; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Muller, Dominik; Müller, Janine; Müller, Katharina; Müller, Vanessa; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nandi, Anita; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Ninci, Daniele; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Osorio Rodrigues, Bruno; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Pappenheimer, Cheryl; Parkes, Christopher; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petruzzo, Marco; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Piucci, Alessio; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Ronayne, John William; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santimaria, Marco; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schubiger, Maxime; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Siddi, Benedetto Gianluca; Silva Coutinho, Rafael; Silva de Oliveira, Luiz Gustavo; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skillicorn, Ian; Skwarnicki, Tomasz; Smith, Edmund; Smith, Eluned; Smith, Iwan Thomas; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Stefkova, Slavorima; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szumlak, Tomasz; T'Jampens, Stephane; Tayduganov, Andrey; Tekampe, Tobias; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Todd, Jacob; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Williams, Timothy; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xu, Zhirui; Yang, Zhenwei; Yu, Jiesheng; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang; Zucchelli, Stefano
2015-01-01
An algorithm is described for tagging the flavour content at production of neutral $B$ mesons in the LHCb experiment. The algorithm exploits the correlation of the flavour of a $B$ meson with the charge of a reconstructed secondary charm hadron from the decay of the other $b$ hadron produced in the proton-proton collision. Charm hadron candidates are identified in a number of fully or partially reconstructed Cabibbo-favoured decay modes. The algorithm is calibrated on the self-tagged decay modes $B^+ \\to J/\\psi \\, K^+$ and $B^0 \\to J/\\psi \\, K^{*0}$ using $3.0\\mathrm{\\,fb}^{-1}$ of data collected by the LHCb experiment at $pp$ centre-of-mass energies of $7\\mathrm{\\,TeV}$ and $8\\mathrm{\\,TeV}$. Its tagging power on these samples of $B \\to J/\\psi \\, X$ decays is $(0.30 \\pm 0.01 \\pm 0.01) \\%$.
Search for Flavoured Multiquarks in a Simple Bag Model
Zouzou, S
1993-01-01
We use a bag model to study flavoured mesonic $(Qq\\bar q\\bar q)$ and baryonic $({\\overline Q}qqqq)$ states, where one heavy quark $Q$ is associated with light quarks or antiquarks, and search for possible stable multiquarks. No bound state is found. However some states lie not too high above their dissociation threshold, suggesting the possibility of resonances, or perhaps bound states in improved models.
Phenomenological constraints on the flavour asymmetry of the nucleon sea
Energy Technology Data Exchange (ETDEWEB)
Martin, A.D.; Stirling, W.J. [Durham Univ. (United Kingdom). Dept. of Physics; Roberts, R.G.
1993-03-01
We study the possible flavour asymmetry, u-bar {ne} d-bar, of the light quark sea distributions of the proton. We discuss the information that is at present available from data on deep-inelastic lepton-nucleon scattering and from Drell-Yan production on various nuclear targets. We show that the ratio of dilepton yields on hydrogen and deuterium targets is very sensitive to u-bar - d-bar. (author).
Analytical Analysis and Numerical Solution of Two Flavours Skyrmion
Hadi, Miftachul; Hermawanto, Denny
2010-01-01
Two flavours Skyrmion will be analyzed analytically, in case of static and rotational Skyrme equations. Numerical solution of a nonlinear scalar field equation, i.e. the Skyrme equation, will be worked with finite difference method. This article is a more comprehensive version of \\textit{SU(2) Skyrme Model for Hadron} which have been published at Journal of Theoretical and Computational Studies, Volume \\textbf{3} (2004) 0407.
The supersymmetric Higgs boson with flavoured A-terms
Directory of Open Access Journals (Sweden)
Andrea Brignole
2015-09-01
Full Text Available We consider a supersymmetric scenario with large flavour violating A-terms in the stop/scharm sector and study their impact on the Higgs mass, the electroweak ρ parameter and the effective Higgs couplings to gluons, photons and charm quarks. For each observable we present explicit analytical expressions which exhibit the relevant parametric dependences, both in the general case and in specific limits. We find significant effects and comment on phenomenological implications for the LHC and future colliders.
Heavy-flavour transport: from large to small systems
Beraudo, A; Monteno, M; Nardi, M; Prino, F
2015-01-01
Predictions for heavy-flavour production in relativistic heavy-ion experiments provided by the POWLANG transport setup, including now also an in-medium hadronization model, are displayed, After showing some representative findings for the Au-Au and Pb-Pb cases, a special focus will be devoted to the results obtained in the small systems formed in proton(deuteron)-nucleus collisions, where recent experimental data suggest the possible formation of a medium featuring a collective behaviour.
Flavour in heavy neutrino searches at the LHC
Aguilar-Saavedra, J A; Kittel, O; Valle, J W F
2012-01-01
Heavy neutrinos at the TeV scale have been searched for at the LHC in the context of left-right models, under the assumption that they couple to the electron, the muon, or both. We show that current searches are also sensitive to heavy neutrinos coupling predominantly to the tau lepton, and present limits can significantly constrain the parameter space of general flavour mixing.
Open flavour charmed mesons in a quantum chromodynamics potential model
Indian Academy of Sciences (India)
Krishna Kingkar Pathak; D K Choudhury
2012-12-01
We modify the mesonic wave function by using a short distance scale 0 in analogy with hydrogen atom and estimate the values of masses and decay constants of the open flavour charm mesons , $D_{s}$ and $B_{c}$ within the framework of a QCD potential model. We also calculate leptonic decay widths of these mesons to study branching ratios and lifetime. The results are in good agreement with experimental and other theoretical values.
Violation of lepton flavour universality in composite Higgs models
Niehoff, Christoph; Straub, David M
2015-01-01
We investigate whether the the $2.6\\sigma$ deviation from lepton flavour universality in $B^+\\to K^+\\ell^+\\ell^-$ decays recently observed at the LHCb experiment can be explained in minimal composite Higgs models. We show that a visible departure from universality is indeed possible if left-handed muons have a sizable degree of compositeness. Constraints from $Z$-pole observables are avoided by a custodial protection of the muon coupling.
Three-Higgs-doublet models: symmetries, potentials and Higgs boson masses
Energy Technology Data Exchange (ETDEWEB)
Keus, Venus [School of Physics and Astronomy, University of Southampton,Southampton, SO17 1BJ (United Kingdom); Department of Physics, Royal Holloway, University of London,Egham Hill, Egham TW20 0EX (United Kingdom); Particle Physics Department, Rutherford Appleton Laboratory,Chilton, Didcot, Oxon OX11 0QX (United Kingdom); King, Stephen F. [School of Physics and Astronomy, University of Southampton,Southampton, SO17 1BJ (United Kingdom); Moretti, Stefano [School of Physics and Astronomy, University of Southampton,Southampton, SO17 1BJ (United Kingdom); Particle Physics Department, Rutherford Appleton Laboratory,Chilton, Didcot, Oxon OX11 0QX (United Kingdom)
2014-01-13
We catalogue and study three-Higgs-doublet models in terms of all possible allowed symmetries (continuous and discrete, Abelian and non-Abelian), where such symmetries may be identified as flavour symmetries of quarks and leptons. We analyse the potential in each case, and derive the conditions under which the vacuum alignments (0,0,v), (0,v,v) and (v,v,v) are minima of the potential. For the alignment (0,0,v), relevant for dark matter models, we calculate the corresponding physical Higgs boson mass spectrum. Motivated by supersymmetry, we extend the analysis to the case of three up-type Higgs doublets and three down-type Higgs doublets (six doublets in total). Many of the results are also applicable to flavon models where the three Higgs doublets are replaced by three electroweak singlets.
Radiative seesaw: Warm dark matter, collider and lepton flavour violating signals
Sierra, D Aristizabal; Restrepo, D; Suematsu, Daijiro; Zapata, Oscar
2008-01-01
Extending the standard model with three right-handed neutrinos ($N_k$) and a second Higgs doublet ($\\eta$), odd under the discrete parity symmetry $Z_2$, Majorana neutrino masses can be generated at 1-loop order. In the resulting model, the lightest stable particle, either a boson or a fermion, might be a dark matter candidate. Here we assume a specific mass spectrum ($M_1\\ll M_2 < M_3 < m_\\eta$) and derive its consequences for dark matter and collider phenomenology. We show that (i) the lightest right-handed neutrino is a warm dark matter particle that can give a $\\sim$10% contribution to the dark matter density; (ii) several decay branching ratios of the charged scalar can be predicted from measured neutrino data. Especially interesting is that large lepton flavour violating rates in muon and tau final states are expected. Finally, we derive upper bounds on the right-handed neutrino Yukawa couplings from the current experimental limit on $Br(\\mu\\to e\\gamma)$.
A $Z^\\prime$ Model for $b\\to s \\ell\\bar \\ell$ Flavour Anomalies
Chiang, Cheng-Wei; Valencia, German
2016-01-01
We study the implications of flavour-changing neutral currents (FCNC's) in a model with the $SU(2)_l\\times SU(2)_h\\times U(1)_Y$ electroweak gauge symmetry for several anomalies appearing in $b\\to s \\ell\\bar \\ell$ induced $B$ decays in LHCb data. In this model, $SU(2)_l$ and $SU(2)_h$ govern the left-handed fermions in the first two generations and the third generation, respectively. The physical $Z$ and $Z'$ generate the $b\\to s$ transition at tree level, leading to additional contributions to the $b \\to s$ semileptonic operators ${\\cal O}_{9,10}$. We find that although $B_s$-$\\bar B_s$ mixing constrains the parameters severely, the model can produce values of ${\\cal C}^{\\rm NP}_{9,10}$ in the range determined by Descotes-Genon {\\it et. al.} in Ref.~\\cite{Descotes-Genon:2015uva} for this scenario to improve the global fit of observables in decays induced by the $b\\to s \\mu \\bar \\mu$ transition. The $Z'$ boson in this model also generates tree-level FCNC's for the leptonic interactions that can accommodate th...
Search for Lepton Flavour Violation in ep Collisions at HERA
Aktas, A; Andreev, V; Anthonis, T; Antunovic, B; Aplin, S; Asmone, A; Astvatsatourov, A; Babaev, A; Backovic, S; Baghdasaryan, A; Baranov, P; Barrelet, E; Bartel, Wulfrin; Baudrand, S; Beckingham, M; Begzsuren, K; Behnke, O; Behrendt, O; Belousov, A; Berger, N; Bizot, J C; Boenig, M O; Boudry, V; Bozovic-Jelisavcic, I; Bracinik, J; Brandt, G; Brinkmann, M; Brisson, V; Bruncko, D; Büsser, F W; Bunyatyan, A; Buschhorn, G; Bystritskaya, L; Campbell, A J; Cantun Avila, K B; Cassol-Brunner, F; Cerny, K; Cerny, V; Chekelian, V; Cholewa, A; Contreras, J G; Coughlan, J A; Cozzika, G; Cvach, J; Dainton, J B; Daum, K; De Boer, Y; Delcourt, B; Del Degan, M; de Roeck, A; De Wolf, E A; Diaconu, C; Dodonov, V; Dubak, A; Eckerlin, G; Efremenko, V; Egli, S; Eichler, R; Eisele, F; Eliseev, A; Elsen, E; Essenov, S; Falkewicz, A; Faulkner, P J W; Favart, L; Fedotov, A; Felst, R; Feltesse, J; Ferencei, J; Finke, L; Fleischer, M; Fomenko, A; Franke, G; Frisson, T; Gabathuler, E; Garutti, E; Gayler, J; Ghazaryan, S; Ginzburgskaya, S; Glazov, A; Glushkov, I; Görlich, L; Goettlich, M; Gogitidze, N; Gorbounov, S; Gouzevitch, M; Grab, C; Greenshaw, T; Gregori, M; Grell, B R; Grindhammer, G; Habib, S; Haidt, D; Hansson, M; Heinzelmann, G; Helebrant, C; Henderson, R C W; Henschel, H; Herrera-Corral, G; Hildebrandt, M; Hiller, K H; Hoffmann, D; Horisberger, Roland Paul; Hovhannisyan, A; Hreus, T; Hussain, S; Jacquet, M; Janssen, M E; Janssen, X; Jemanov, V; Jönsson, L B; Johnson, D P; Jung, A W; Jung, H; Kapichine, M; Katzy, J; Kenyon, I R; Kiesling, C; Klein, M; Kleinwort, C; Klimkovich, T; Kluge, T; Knies, G; Knutsson, A; Korbel, V; Kostka, P; Krämer, M; Krastev, K; Kretzschmar, J; Kropivnitskaya, A; Krüger, K; Landon, M P J; Lange, W; Lastoviicka-Medin, G; Laycock, P; Lebedev, A; Leibenguth, G; Lendermann, V; Levonian, S; Lindfeld, L; Lipka, K; Liptaj, A; List, B; List, J; Loktionova, N; López-Fernandez, R; Lubimov, V; Lucaci-Timoce, A I; Lüders, H; Lytkin, L; Makankine, A; Malinovskii, E I; Marage, P; Marti, L; Martisikova, M; Martyn, H U; Maxfield, S J; Mehta, A; Meier, K; Meyer, A B; Meyer, H; Meyer, J; Michels, V; Mikocki, S; Milcewicz-Mika, I; Mladenov, D; Mohamed, A; Moreau, F; Morozov, A; Morris, J V; Mozer, M U; Müller, K; Murn, P; Nankov, K; Naroska, B; Naumann, T; Newman, P R; Niebuhr, C; Nikiforov, A; Nowak, G; Nowak, K; Nozicka, M; Oganezov, R; Olivier, B; Olsson, J E; Osman, S; Ozerov, D; Palichik, V; Panagoulias, I; Pandurovic, M; Papadopoulou, T; Pascaud, C; Patel, G D; Peng, H; Pérez, E; Perez-Astudillo, D; Perieanu, A; Petrukhin, A; Picuric, I; Piec, S; Pitzl, D; Placakyte, R; Povh, B; Preda, T; Prideaux, P; Rahmat, A J; Raicevic, N; Ravdandorj, T; Reimer, P; Rimmer, A; Risler, C; Rizvi, E; Robmann, P; Roland, B; Roosen, R; Rostovtsev, A; Rurikova, Z; Rusakov, S; Salvaire, F; Sankey, D P C; Sauter, M; Sauvan, E; Schmidt, S; Schmitt, S; Schmitz, C; Schoeffel, L; Schöning, A; Schultz-Coulon, H C; Sefkow, F; Shaw-West, R N; Shevyakov, I; Shtarkov, L N; Sloan, T; Smiljanic, I; Smirnov, P; Soloviev, Yu; South, D; Spaskov, V; Specka, A; Steder, M; Stella, B; Stiewe, J; Straumann, U; Sunar, D; Sykora, T; Tchoulakov, V; Thompson, G; Thompson, P D; Toll, T; Tomasz, F; Traynor, D; Trinh, T N; Truöl, P; Tsakov, I; Tseepeldorj, B; Tsipolitis, G; Tsurin, I; Turnau, J; Tzamariudaki, E; Urban, K; Usik, A; Utkin, D; Valkárová, A; Vallée, C; Van Mechelen, P; Vargas-Trevino, A; Vazdik, Ya; Vinokurova, S; Volchinski, V; Wacker, K; Weber, G; Weber, R; Wegener, D; Werner, C; Wessels, M; Wissing, C; Wolf, R; Wünsch, E; Xella, S M; Yan, W; Yeganov, V; Zácek, J; Zálesák, J; Zhang, Z; Zhelezov, A; Zhokin, A; Zhu, Y C; Zimmermann, J; Zimmermann, T; Zohrabyan, H; Zomer, F
2007-01-01
A search for the lepton flavour violating processes ep->mu X and ep -> tau X is performed with the H1 experiment at HERA. Final states with a muon or tau and a hadronic jet are searched for in a data sample corresponding to an integrated luminosity of 66.5 pb-1 for e^+ p collisions and 13.7 pb^-1 for e^- p collisions at a centre-of-mass energy of 319 GeV. No evidence for lepton flavour violation is found. Limits are derived on the mass and the couplings of leptoquarks inducing lepton flavour violation in an extension of the Buchm"uller-R"uckl-Wyler effective model. Leptoquarks produced in ep collisions with a coupling strength of lambda=0.3 and decaying with the same coupling strength to a muon-quark pair or a tau-quark pair are excluded at 95% confidence level up to masses of 459 GeV and 379 GeV, respectively.
A Bio-Inspired Herbal Tea Flavour Assessment Technique
Directory of Open Access Journals (Sweden)
Nur Zawatil Isqi Zakaria
2014-07-01
Full Text Available Herbal-based products are becoming a widespread production trend among manufacturers for the domestic and international markets. As the production increases to meet the market demand, it is very crucial for the manufacturer to ensure that their products have met specific criteria and fulfil the intended quality determined by the quality controller. One famous herbal-based product is herbal tea. This paper investigates bio-inspired flavour assessments in a data fusion framework involving an e-nose and e-tongue. The objectives are to attain good classification of different types and brands of herbal tea, classification of different flavour masking effects and finally classification of different concentrations of herbal tea. Two data fusion levels were employed in this research, low level data fusion and intermediate level data fusion. Four classification approaches; LDA, SVM, KNN and PNN were examined in search of the best classifier to achieve the research objectives. In order to evaluate the classifiers’ performance, an error estimator based on k-fold cross validation and leave-one-out were applied. Classification based on GC-MS TIC data was also included as a comparison to the classification performance using fusion approaches. Generally, KNN outperformed the other classification techniques for the three flavour assessments in the low level data fusion and intermediate level data fusion. However, the classification results based on GC-MS TIC data are varied.
Optimization of Flavour Tagging Algorithms for the LHCb Experiment
Heinicke, Kevin
Studies of $C\\!P$ violation can be used to test the Standard Model and might give insight into New Physics. Therefore, a wide range of $C\\!P$ measurements, including time-dependent decay rate measurements, are performed with the LHCb Experiment. Many of these are subject to mixing of neutral $B$ meson states with their antiparticles. The knowledge of the initial $B$ flavour is essential in these cases which is why several Flavour Tagging algorithms are used to deduce this information from the available event properties. These algorithms must be adjusted to changes in the shape of the event properties, resulting from an upgrade of the LHC centre-of-mass energy to $\\sqrt{s} = 13\\,\\mathrm{TeV}$. To simplify this process, the Flavour Tagging software is re-implemented. The tagging power of the muon, electron and kaon tagger is measured based on $B^+ \\to J\\!/\\!\\psi K^+$ data, which is processed within the new framework. It is found to be $(0.782 ± 0.018)\\%$, $(0.243 ± 0.011)\\%$ and $(0.649 ± 0.020)\\%$ for Run 1...
Extended Minimal Flavour Violating MSSM and Implications for B Physics
Ali, A
2001-01-01
Current world average of the CP asymmetry a(psi K), obtained from the rate differences in the decays B^0 -> (J/psi K_S), (J/psi K_L) and their charge conjugates, is barely compatible with the standard model (SM) predictions resulting from the unitarity of the CKM matrix. Indirect estimate of this CP asymmetry in the so-called minimal flavour violating (MFV) supersymmetric extensions of the standard model, in which the CKM matrix remains the only flavour changing structure, is similar to the one in the SM. If the present experimental trend yielding a(psi K,exp) - a(psi K,SM) d gamma as sensitive probes of the postulated flavour changing structure. This is quantified in terms of the ratio R(rho gamma/K* gamma) = 2 B(B^0 -> rho^0 gamma)/B(B^0 -> K^*0 gamma), the isospin violating ratio Delta=B(B^+ -> rho^+ gamma)/2B(B^0 -> rho^0 gamma) -1, and the CP-asymmetry in the decay rates for B^+ -> rho^+ gamma and its charge conjugate.
Following butter flavour deterioration with an acoustic wave sensor.
Gaspar, Cláudia R B S; Gomes, M Teresa S R
2012-09-15
Off-flavours develop naturally in butter and the process is accelerated by heat. An acoustic wave sensor was used to detect the aroma compounds evolved from heated butter and the results have shown that registered marked changes were coincident to odour changes detected by sensory analysis. The flavour compounds have also been analysed by GC/MS for identification. The response of the sensor was fully characterized in terms of the sensitivity to each of the identified compounds, and sensitivities of the system SPME/sensor were compared with the sensitivities of the system SPME/GC/MS. It was found that the sensor analytical system was more sensitive to methylketones than to fatty acids. The SPME/GC/MS system also showed the highest sensitivity to 2-heptanone, followed by 2-nonanone, but third place was occupied by undecanone and butanoic acid, to which the sensor showed moderate sensitivity. 2-heptanone was found to be an appropriate model compound to follow odour changes till the 500 h, and the lower sensitivity of the sensor to butanoic acid showed to be a positive characteristic, as saturation was prevented, and other more subtle changes in the flavour could be perceived.
Hints for new sources of flavour violation in meson mixing
Blanke, Monika
2016-01-01
The recent results by the Fermilab Lattice and MILC collaborations on the hadronic matrix elements entering $B_{d,s}-\\bar B_{d,s}$ mixing show a significant tension of the measured values of the mass differences $\\Delta M_{d,s}$ with their SM predictions. We review the implications of these results in the context of Constrained Minimal Flavour Violation models. In these models, the CKM elements $\\gamma$ and $|V_{ub}|/|V_{cb}|$ can be determined from $B_{d,s}-\\bar B_{d,s}$ mixing observables, yielding a prediction for $\\gamma$ below its tree-level value. Determining subsequently $|V_{cb}|$ from the measured value of either $\\Delta M_s$ or $\\varepsilon_K$ gives inconsistent results, with the tension being smallest in the Standard Model limit. This tension can be resolved if the flavour universality of new contributions to $\\Delta F = 2$ observables is broken. We briefly discuss the case of $U(2)^3$ flavour models as an illustrative example.
Regular Symmetry Patterns (Technical Report)
Lin, Anthony W.; Nguyen, Truong Khanh; Rümmer, Philipp; Sun, Jun
2015-01-01
Symmetry reduction is a well-known approach for alleviating the state explosion problem in model checking. Automatically identifying symmetries in concurrent systems, however, is computationally expensive. We propose a symbolic framework for capturing symmetry patterns in parameterised systems (i.e. an infinite family of finite-state systems): two regular word transducers to represent, respectively, parameterised systems and symmetry patterns. The framework subsumes various types of symmetry ...
Baldo, M
2016-01-01
The nuclear symmetry energy characterizes the variation of the binding energy as the neutron to proton ratio of a nuclear system is varied. This is one of the most important features of nuclear physics in general, since it is just related to the two component nature of the nuclear systems. As such it is one of the most relevant physical parameters that affect the physics of many phenomena and nuclear processes. This review paper presents a survey of the role and relevance of the nuclear symmetry energy in different fields of research and of the accuracy of its determination from the phenomenology and from the microscopic many-body theory. In recent years, a great interest was devoted not only to the Nuclear Matter symmetry energy at saturation density but also to its whole density dependence, which is an essential ingredient for our understanding of many phenomena. We analyze the nuclear symmetry energy in different realms of nuclear physics and astrophysics. In particular we consider the nuclear symmetry ene...
Loebbert, Florian
2016-08-01
In these introductory lectures we discuss the topic of Yangian symmetry from various perspectives. Forming the classical counterpart of the Yangian and an extension of ordinary Noether symmetries, first the concept of nonlocal charges in classical, two-dimensional field theory is reviewed. We then define the Yangian algebra following Drinfel’d's original motivation to construct solutions to the quantum Yang-Baxter equation. Different realizations of the Yangian and its mathematical role as a Hopf algebra and quantum group are discussed. We demonstrate how the Yangian algebra is implemented in quantum, two-dimensional field theories and how its generators are renormalized. Implications of Yangian symmetry on the two-dimensional scattering matrix are investigated. We furthermore consider the important case of discrete Yangian symmetry realized on integrable spin chains. Finally we give a brief introduction to Yangian symmetry in planar, four-dimensional super Yang-Mills theory and indicate its impact on the dilatation operator and tree-level scattering amplitudes. These lectures are illustrated by several examples, in particular the two-dimensional chiral Gross-Neveu model, the Heisenberg spin chain and { N }=4 superconformal Yang-Mills theory in four dimensions.
Loebbert, Florian
2016-08-01
In these introductory lectures we discuss the topic of Yangian symmetry from various perspectives. Forming the classical counterpart of the Yangian and an extension of ordinary Noether symmetries, first the concept of nonlocal charges in classical, two-dimensional field theory is reviewed. We then define the Yangian algebra following Drinfel’d's original motivation to construct solutions to the quantum Yang–Baxter equation. Different realizations of the Yangian and its mathematical role as a Hopf algebra and quantum group are discussed. We demonstrate how the Yangian algebra is implemented in quantum, two-dimensional field theories and how its generators are renormalized. Implications of Yangian symmetry on the two-dimensional scattering matrix are investigated. We furthermore consider the important case of discrete Yangian symmetry realized on integrable spin chains. Finally we give a brief introduction to Yangian symmetry in planar, four-dimensional super Yang–Mills theory and indicate its impact on the dilatation operator and tree-level scattering amplitudes. These lectures are illustrated by several examples, in particular the two-dimensional chiral Gross–Neveu model, the Heisenberg spin chain and { N }=4 superconformal Yang–Mills theory in four dimensions.
Implications of N=4 superconformal symmetry in three spacetime dimensions
Buchbinder, Evgeny I; Samsonov, Igor B
2015-01-01
We study implications of N=4 superconformal symmetry in three dimensions, thus extending our earlier results in arXiv:1503.04961 devoted to the N=1,2,3 cases. We show that the three-point function of the supercurrent in N=4 superconformal field theories contains two linearly independent forms. However, only one of these structures contributes to the three-point function of the energy-momentum tensor and the other one is present in those N=4 superconformal theories which are not invariant under the mirror map. We point out that general N=4 superconformal field theories admit two inequivalent flavour current multiplets and show that the three-point function of each of them is determined by one tensor structure. As an example, we compute the two- and three-point functions of the conserved currents in N=4 superconformal models of free hypermultiplets. We also derive the universal relations between the coefficients appearing in the two- and three-point correlators of the supercurrent and flavour current multiplets...
Dark Matter and Dark Energy via Non-Perturbative (Flavour) Vacua
Tarantino, Walter
2011-01-01
A non-perturbative field theoretical approach to flavour physics (Blasone-Vitiello formalism) has been shown to imply a highly non-trivial vacuum state. In a previous work, we implemented the approach on a simple supersymmetric model (free Wess-Zumino), with flavour mixing, which was regarded as a model for free neutrinos and sneutrinos. The resulting effective vacuum (called "flavour vacuum") was found to be characterized by a strong SUSY breaking. In this paper we explore the phenomenology ...
Authenticity and Traceability of Vanilla Flavour by Analysis of Stable Isotopes
Hansen, Anne-Mette Sølvbjerg; Fromberg, Arvid; Frandsen, Henrik Lauritz
2014-01-01
For authentification of vanilla flavours, vanilla pods of the type Vanilla planifolia and Vanilla tahitensis from different geographical habitats were extracted and analyzed together with vanilla flavours made by fermentations and chemical synthesis. Isotopic delta values were determined using Gas Chromatography Isotope Ratio Mass Spectrometry (GC-IRMS). The main contributor to the characteristic vanilla flavour is 4-hydroxy-3-methoxybenzaldehyde, also called vanillin. Delta13C values of vani...
Zong-Min Wang; Zhen-Ming Lu; Jin-Song Shi; Zheng-Hong Xu
2016-01-01
Multispecies solid-state fermentation (MSSF), a natural fermentation process driven by reproducible microbiota, is an important technique to produce traditional fermented foods. Flavours, skeleton of fermented foods, was mostly produced by microbiota in food ecosystem. However, the association between microbiota and flavours and flavour-producing core microbiota are still poorly understood. Here, acetic acid fermentation (AAF) of Zhenjiang aromatic vinegar was taken as a typical case of MSSF....
Engels, W.J.M.
1997-01-01
Flavour is one of the most important attributes of cheese. Cheese flavour is the result of the breakdown of milk protein, fat, lactose and citrate due to enzymes from milk, rennet and microorganisms during production and ripening of cheese. For a large part the development of flavour during the ripening of cheese is determined by the process of proteolysis of caseins. Over the past years proteolysis has been studied very extensively and as a result a wealth of information about this process h...
Shah, A.K.M. Azad; Ogasawara, Masashi; Egi, Makoto; Kurihara, Hideyuki; Takahashi, Koretaro
2010-01-01
Flavour-enhancing components of dried herring fillet (migaki-nishin in Japanese) were isolated and evaluated for their effects on sensory perception. Sensory evaluation revealed that addition of dried herring fillet water-soluble extracts to Japanese noodle soup significantly (P < 0.05) enhanced the soup flavour characters such as thickness, mouthfulness and continuity. The extracts were fractionated by dialysis and chromatography. Fractions containing flavour enhancers were isolated by senso...
Trautmann, Wolfgang; Russotto, Paolo
2016-01-01
The nuclear equation-of-state is a topic of highest current interest in nuclear structure and reactions as well as in astrophysics. In particular, the equation-of-state of asymmetric matter and the symmetry energy representing the difference between the energy densities of neutron matter and of symmetric nuclear matter are not sufficiently well constrained at present. The density dependence of the symmetry energy is conventionally expressed in the form of the slope parameter L describing the derivative with respect to density of the symmetry energy at saturation. Results deduced from nuclear structure and heavy-ion reaction data are distributed around a mean value L=60 MeV. Recent studies have more thoroughly investigated the density range that a particular observable is predominantly sensitive to. Two thirds of the saturation density is a value typical for the information contained in nuclear-structure data. Higher values exceeding saturation have been shown to be probed with meson production and collective ...
DEFF Research Database (Denmark)
Avery, John Scales; Rettrup, Sten; Avery, James Emil
automatically with computer techniques. The method has a wide range of applicability, and can be used to solve difficult eigenvalue problems in a number of fields. The book is of special interest to quantum theorists, computer scientists, computational chemists and applied mathematicians....... eigenfunctions and eigenvalues for the Hamiltonian of a many-particle system is usually so difficult that it requires approximate methods, the most common of which is expansion of the eigenfunctions in terms of basis functions that obey the boundary conditions of the problem. The computational effort needed...... in such problems can be much reduced by making use of symmetry-adapted basis functions. The conventional method for generating symmetry-adapted basis sets is through the application of group theory, but this can be difficult. This book describes an easier method for generating symmetry-adapted basis sets...
Weiss, Asia; Whiteley, Walter
2014-01-01
This book contains recent contributions to the fields of rigidity and symmetry with two primary focuses: to present the mathematically rigorous treatment of rigidity of structures, and to explore the interaction of geometry, algebra, and combinatorics. Overall, the book shows how researchers from diverse backgrounds explore connections among the various discrete structures with symmetry as the unifying theme. Contributions present recent trends and advances in discrete geometry, particularly in the theory of polytopes. The rapid development of abstract polytope theory has resulted in a rich theory featuring an attractive interplay of methods and tools from discrete geometry, group theory, classical geometry, hyperbolic geometry and topology. The volume will also be a valuable source as an introduction to the ideas of both combinatorial and geometric rigidity theory and its applications, incorporating the surprising impact of symmetry. It will appeal to students at both the advanced undergraduate and gradu...
Energy Technology Data Exchange (ETDEWEB)
Chanowitz, M.S.
1990-09-01
The Higgs mechanism is reviewed in its most general form, requiring the existence of a new symmetry-breaking force and associated particles, which need not however be Higgs bosons. The first lecture reviews the essential elements of the Higgs mechanism, which suffice to establish low energy theorems for the scattering of longitudinally polarized W and Z gauge bosons. An upper bound on the scale of the symmetry-breaking physics then follows from the low energy theorems and partial wave unitarity. The second lecture reviews particular models, with and without Higgs bosons, paying special attention to how the general features discussed in lecture 1 are realized in each model. The third lecture focuses on the experimental signals of strong WW scattering that can be observed at the SSC above 1 TeV in the WW subenergy, which will allow direct measurement of the strength of the symmetry-breaking force. 52 refs., 10 figs.
Hidden Symmetry Subgroup Problems
Decker, Thomas; Santha, Miklos; Wocjan, Pawel
2011-01-01
We advocate a new approach of addressing hidden structure problems and finding efficient quantum algorithms. We introduce and investigate the Hidden Symmetry Subgroup Problem (HSSP), which is a generalization of the well-studied Hidden Subgroup Problem (HSP). Given a group acting on a set and an oracle whose level sets define a partition of the set, the task is to recover the subgroup of symmetries of this partition inside the group. The HSSP provides a unifying framework that, besides the HSP, encompasses a wide range of algebraic oracle problems, including quadratic hidden polynomial problems. While the HSSP can have provably exponential quantum query complexity, we obtain efficient quantum algorithms for various interesting cases. To achieve this, we present a general method for reducing the HSSP to the HSP, which works efficiently in several cases related to symmetries of polynomials. The HSSP therefore connects in a rather surprising way certain hidden polynomial problems with the HSP. Using this connect...
Scharnhorst, K.
1996-01-01
Within Euclidean lattice field theory an exact equivalence between the one-flavour 2D Thirring model with Wilson fermions and Wilson parameter $r = 1$ to a two-colour loop model on the square lattice is established. For non-interacting fermions this model reduces to an exactly solved loop model which is known to be a free fermion model. The two-colour loop model equivalent to the Thirring model can also be understood as a 4-state 49-vertex model.
Experimental constraints from flavour changing processes and physics beyond the Standard Model
Gersabeck, M.; Gligorov, V. V.; Serra, N.
2012-08-01
Flavour physics has a long tradition of paving the way for direct discoveries of new particles and interactions. Results over the last decade have placed stringent bounds on the parameter space of physics beyond the Standard Model. Early results from the LHC, and its dedicated flavour factory LHCb, have further tightened these constraints and reiterate the ongoing relevance of flavour studies. The experimental status of flavour observables in the charm and beauty sectors is reviewed in measurements of CP violation, neutral meson mixing, and measurements of rare decays.
Experimental constraints from flavour changing processes and physics beyond the standard model
Energy Technology Data Exchange (ETDEWEB)
Gersabeck, M.; Gligorov, V.V. [CERN, Geneva (Switzerland); Serra, N. [University of Zuerich (Switzerland)
2012-08-15
Flavour physics has a long tradition of paving the way for direct discoveries of new particles and interactions. Results over the last decade have placed stringent bounds on the parameter space of physics beyond the Standard Model. Early results from the LHC, and its dedicated flavour factory LHCb, have further tightened these constraints and reiterate the ongoing relevance of flavour studies. The experimental status of flavour observables in the charm and beauty sectors is reviewed in measurements of CP violation, neutral meson mixing, and measurements of rare decays. (orig.)
Liu, Keh-Fei
2016-01-01
The relevance of chiral symmetry in baryons is highlighted in three examples in the nucleon spectroscopy and structure. The first one is the importance of chiral dynamics in understanding the Roper resonance. The second one is the role of chiral symmetry in the lattice calculation of $\\pi N \\sigma$ term and strangeness. The third one is the role of chiral $U(1)$ anomaly in the anomalous Ward identity in evaluating the quark spin and the quark orbital angular momentum. Finally, the chiral effective theory for baryons is discussed.
Foot, R; Volkas, R R
1992-01-01
Quark-lepton symmetric models are a class of gauge theories motivated by the similarities between the quarks and leptons. In these models the gauge group of the standard model is extended to include a ``color'' group for the leptons. Consequently, the quarks and leptons can then be related by a $Z_2$ discrete quark-lepton symmetry which is spontaneously broken by the vacuum. Models utilizing quark-lepton symmetry with acceptable and interesting collider phenomenology have been constructed. The cosmological consequences of these models are also discussed.
Arzano, Michele; Kowalski-Glikman, Jerzy
2016-09-01
We construct discrete symmetry transformations for deformed relativistic kinematics based on group valued momenta. We focus on the specific example of κ-deformations of the Poincaré algebra with associated momenta living on (a sub-manifold of) de Sitter space. Our approach relies on the description of quantum states constructed from deformed kinematics and the observable charges associated with them. The results we present provide the first step towards the analysis of experimental bounds on the deformation parameter κ to be derived via precision measurements of discrete symmetries and CPT.
Weakly broken galileon symmetry
Energy Technology Data Exchange (ETDEWEB)
Pirtskhalava, David [Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa (Italy); Santoni, Luca; Trincherini, Enrico [Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa (Italy); INFN, Sezione di Pisa, Piazza dei Cavalieri 7, 56126 Pisa (Italy); Vernizzi, Filippo [Institut de Physique Théorique, Université Paris Saclay, CEA, CNRS, Gif-sur-Yvette cédex, F-91191 (France)
2015-09-01
Effective theories of a scalar ϕ invariant under the internal galileon symmetryϕ→ϕ+b{sub μ}x{sup μ} have been extensively studied due to their special theoretical and phenomenological properties. In this paper, we introduce the notion of weakly broken galileon invariance, which characterizes the unique class of couplings of such theories to gravity that maximally retain their defining symmetry. The curved-space remnant of the galileon’s quantum properties allows to construct (quasi) de Sitter backgrounds largely insensitive to loop corrections. We exploit this fact to build novel cosmological models with interesting phenomenology, relevant for both inflation and late-time acceleration of the universe.
Measures with symmetry properties
Schindler, Werner
2003-01-01
Symmetries and invariance principles play an important role in various branches of mathematics. This book deals with measures having weak symmetry properties. Even mild conditions ensure that all invariant Borel measures on a second countable locally compact space can be expressed as images of specific product measures under a fixed mapping. The results derived in this book are interesting for their own and, moreover, a number of carefully investigated examples underline and illustrate their usefulness and applicability for integration problems, stochastic simulations and statistical applications.
Symmetry, structure, and spacetime
Rickles, Dean
2007-01-01
In this book Rickles considers several interpretative difficulties raised by gauge-type symmetries (those that correspond to no change in physical state). The ubiquity of such symmetries in modern physics renders them an urgent topic in philosophy of physics. Rickles focuses on spacetime physics, and in particular classical and quantum general relativity. Here the problems posed are at their most pathological, involving the apparent disappearance of spacetime! Rickles argues that both traditional ontological positions should be replaced by a structuralist account according to which relational
Gray, P L
2003-01-01
"The subatomic pion particle breaks the charge symmetry rule that governs both fusion and decay. In experiments performed at the Indiana University Cyclotron Laboratory, physicists forced heavy hydrogen (1 proton + 1 neutron) to fuse into helium in a controlled, measurable environment" (1 paragraph).
Symmetries in fundamental physics
Sundermeyer, Kurt
2014-01-01
Over the course of the last century it has become clear that both elementary particle physics and relativity theories are based on the notion of symmetries. These symmetries become manifest in that the "laws of nature" are invariant under spacetime transformations and/or gauge transformations. The consequences of these symmetries were analyzed as early as in 1918 by Emmy Noether on the level of action functionals. Her work did not receive due recognition for nearly half a century, but can today be understood as a recurring theme in classical mechanics, electrodynamics and special relativity, Yang-Mills type quantum field theories, and in general relativity. As a matter of fact, as shown in this monograph, many aspects of physics can be derived solely from symmetry considerations. This substantiates the statement of E.P.Wigner "... if we knew all the laws of nature, or the ultimate Law of nature, the invariance properties of these laws would not furnish us new information." Thanks to Wigner we now also underst...
Symmetries in fundamental physics
Sundermeyer, Kurt
2014-01-01
Over the course of the last century it has become clear that both elementary particle physics and relativity theories are based on the notion of symmetries. These symmetries become manifest in that the "laws of nature" are invariant under spacetime transformations and/or gauge transformations. The consequences of these symmetries were analyzed as early as in 1918 by Emmy Noether on the level of action functionals. Her work did not receive due recognition for nearly half a century, but can today be understood as a recurring theme in classical mechanics, electrodynamics and special relativity, Yang-Mills type quantum field theories, and in general relativity. As a matter of fact, as shown in this monograph, many aspects of physics can be derived solely from symmetry considerations. This substantiates the statement of E.P. Wigner "... if we knew all the laws of nature, or the ultimate Law of nature, the invariance properties of these laws would not furnish us new information." Thanks to Wigner we now also unders...
Pels, D.L.
1996-01-01
While symmetry and impartiality have become ruling principles in S&TS, defining its core ideal of a 'value-free relativism', their philosophical anchorage has attracted much less discussion than the issue or:how far their jurisdiction can be extended or generalized. This paper seeks to argue that sy
Gauging without Initial Symmetry
Kotov, Alexei
2016-01-01
The gauge principle is at the heart of a good part of fundamental physics: Starting with a group G of so-called rigid symmetries of a functional defined over space-time Sigma, the original functional is extended appropriately by additional Lie(G)-valued 1-form gauge fields so as to lift the symmetry to Maps(Sigma,G). Physically relevant quantities are then to be obtained as the quotient of the solutions to the Euler-Lagrange equations by these gauge symmetries. In this article we show that one can construct a gauge theory for a standard sigma model in arbitrary space-time dimensions where the target metric is not invariant with respect to any rigid symmetry group, but satisfies a much weaker condition: It is sufficient to find a collection of vector fields v_a on the target M satisfying the extended Killing equation v_{a(i;j)}=0 for some connection acting on the index a. For regular foliations this is equivalent to merely requiring the distribution orthogonal to the leaves to be invariant with respect to leaf...
Fields, symmetries, and quarks
International Nuclear Information System (INIS)
'Fields, symmetries, and quarks' covers elements of quantum field theory, symmetries, gauge field theories and phenomenological descriptions of hadrons, with special emphasis on topics relevant to nuclear physics. It is aimed at nuclear physicists in general and at scientists who need a working knowledge of field theory, symmetry principles of elementary particles and their interactions and the quark structure of hadrons. The book starts out with an elementary introduction into classical field theory and its quantization. As gauge field theories require a working knowledge of global symmetries in field theories this topic is then discussed in detail. The following part is concerned with the general structure of gauge field theories and contains a thorough discussion of the still less widely known features of Non-Abelian gauge field theories. Quantum Chromodynamics (QCD), which is important for the understanding of hadronic matter, is discussed in the next section together with the quark compositions of hadrons. The last two chapters give a detailed discussion of phenomenological bag-models. The MIT bag is discussed, so that all theoretical calculations can be followed step by step. Since in all other bag-models the calculational methods and steps are essentially identical, this chapter should enable the reader to actually perform such calculations unaided. A last chapter finally discusses the topological bag-models which have become quite popular over the last few years. (orig.)
Einmahl, John; Gan, Zhuojiong
2016-01-01
Omnibus tests for central symmetry of a bivariate probability distribution are proposed. The test statistics compare empirical measures of opposite regions. Under rather weak conditions, we establish the asymptotic distribution of the test statistics under the null hypothesis; it follows that they a
Crumpecker, Cheryl
2003-01-01
Describes an art lesson used with children in the third grade to help them learn about symmetry, as well as encouraging them to draw larger than usual. Explains that students learn about the belief called "Horror Vacui" of the Northwest American Indian tribes and create their interpretation of this belief. (CMK)
Clader, Emily
2014-01-01
These expository notes are based on lectures by Yongbin Ruan during a special semester on the B-model at the University of Michigan in Winter 2014. They outline and compare the mirror symmetry constructions of Batyrev-Borisov, Hori-Vafa, and Bergland-Hubsch-Krawitz.
Gauging without initial symmetry
Kotov, Alexei; Strobl, Thomas
2016-01-01
The gauge principle is at the heart of a good part of fundamental physics: Starting with a group G of so-called rigid symmetries of a functional defined over space-time Σ, the original functional is extended appropriately by additional Lie(G) -valued 1-form gauge fields so as to lift the symmetry to Maps(Σ , G) . Physically relevant quantities are then to be obtained as the quotient of the solutions to the Euler-Lagrange equations by these gauge symmetries. In this article we show that one can construct a gauge theory for a standard sigma model in arbitrary space-time dimensions where the target metric is not invariant with respect to any rigid symmetry group, but satisfies a much weaker condition: It is sufficient to find a collection of vector fields va on the target M satisfying the extended Killing equationv a(i ; j) = 0 for some connection acting on the index a. For regular foliations this is equivalent to requiring the conormal bundle to the leaves with its induced metric to be invariant under leaf-preserving diffeomorphisms of M, which in turn generalizes Riemannian submersions to which the notion reduces for smooth leaf spaces M / ∼. The resulting gauge theory has the usual quotient effect with respect to the original ungauged theory: in this way, much more general orbits can be factored out than usually considered. In some cases these are orbits that do not correspond to an initial symmetry, but still can be generated by a finite-dimensional Lie group G. Then the presented gauging procedure leads to an ordinary gauge theory with Lie algebra valued 1-form gauge fields, but showing an unconventional transformation law. In general, however, one finds that the notion of an ordinary structural Lie group is too restrictive and should be replaced by the much more general notion of a structural Lie groupoid.
DEFF Research Database (Denmark)
Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister;
The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 28 flavouring substances in the Flavouring Group Evaluation 22, Revision 1, using the Procedure in Commission Regulation (EC) No 1565/2000. The substance 3...... concerns at their levels of dietary intake, estimated on the basis of the MSDI approach. Adequate specifications for the materials of commerce are available for all 27 flavouring substances evaluated through the Procedure....
DEFF Research Database (Denmark)
Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister;
The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate six flavouring substances in the Flavouring Group Evaluation 47, including an additional two substances in this Revision 1, using the Procedure in Commissi...... of these flavouring substances, the specifications for the materials of commerce have also been considered. Adequate specifications including complete purity criteria and identity fo the materials of commerce have been provided for all six candidate substances....
DEFF Research Database (Denmark)
Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister;
The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 37 flavouring substances in the Flavouring Group Evaluation 25, Revision 2, using the Procedure in Commission Regulation (EC) No 1565/2000. None of the sub...... assessment of these flavouring substances, the specifications for the materials of commerce have also been considered. For five substances, the composition of the stereoisomeric mixture has to be specified further....
Discrete Symmetries CP, T, CPT
Bernabeu, J
2016-01-01
The role of Symmetry Breaking mechanisms to search for New Physics is of highest importance. We discuss the status and prospects of the Discrete Symmetries CP, T, CPT looking for their separate Violation in LHC experiments and meson factories.
Symmetry and topology in evolution
International Nuclear Information System (INIS)
This volume contains papers of an interdisciplinary symposium on evolution. The aim of this symposium, held in Budapest, Hungary, 28-29 May 1991, was to clear the role of symmetry and topology at different levels of the evolutionary processes. 21 papers were presented, their topics included evolution of the Universe, symmetry of elementary particles, asymmetry of the Earth, symmetry and asymmetry of biomolecules, symmetry and topology of lining objects, human asymmetry etc. (R.P.)
Aspects of Flavour and Supersymmetry in F-theory GUTs
Conlon, Joseph P; 10.1007
2009-01-01
We study the constraints of supersymmetry on flavour in recently proposed models of F-theory GUTs. We relate the topologically twisted theory to the canonical presentation of eight-dimensional super Yang-Mills and provide a dictionary between the two. We describe the constraints on Yukawa couplings implied by holomorphy of the superpotential in the effective 4-dimensional supergravity theory, including the scaling with \\alpha_{GUT}. Taking D-terms into account we solve explicitly to second order for wavefunctions and Yukawas due to metric and flux perturbations and find a rank-one Yukawa matrix with no subleading corrections.
Flavour breaking effects of Wilson twisted mass fermions
International Nuclear Information System (INIS)
We study the flavour breaking effects appearing in the Wilson twisted mass formulation of lattice QCD. In this quenched study, we focus on the mass splitting between the neutral and the charged pion, determining the neutral pion mass with a stochastic noise method to evaluate the disconnected contributions. We find that these disconnected contributions are significant. Using the Osterwalder-Seiler interpretation of the connected piece of the neutral pion correlator, we compute the corresponding neutral pion mass to study with more precision the scaling behaviour of the mass splitting
Probing lepton flavour violation in slepton NLSP scenarios
Energy Technology Data Exchange (ETDEWEB)
Hamaguchi, Koichi [Deutsches Elektronen-Synchrotron, DESY, 22603 Hamburg (Germany); Ibarra, Alejandro [Department of Physics, Theory Division, CERN, CH-1211 Geneva 23 (Switzerland); Instituto de Fisica Teirica, CSIC/UAM, C-XVI, Universidad Autinoma de Madrid, Cantoblanco, 28049 Madrid (Spain)]. E-mail: ibarra@mail.cern.ch
2005-02-01
In supersymmetric models where the gravitino is the lightest superparticle, the next-to-lightest superparticle (NLSP) is long-lived, and hence could be collected and studied in detail. We study the prospects of direct detection of lepton flavour violation in charged slepton NLSP decays. Mixing angles in the slepton sector as small as {approx} 3x10{sup -2} (9x10{sup -3}) could be probed at the 90% confidence level if 3x10{sup 3} (3x10{sup 4}) sleptons could be collected. (author)
Collider Aspects of Flavour Physics at High Q
Energy Technology Data Exchange (ETDEWEB)
del Aguila, F.; Aguilar-Saavedra, J.A.; Allanach, B.C.; Alwall, J.; Andreev, Yu.; Aristizabal Sierra, D.; Bartl, A.; Beccaria, M.; Bejar, S.; Benucci, L.; Bityukov, S.; Borjanovic, I.; Bozzi, G.; Burdman, G.; Carvalho, J.; Castro, N.; Clerbaux, B.; de Campos, F.; de Gouvea, A.; Dennis, C.; Djouadi, A.; /Cambridge U., DAMTP /Louvain U., CP3 /Moscow, INR /Valencia U. /Vienna U. /Salento U. /INFN, Lecce /Barcelona, Autonoma U. /Barcelona, IFAE /INFN, Pisa /Pisa U. /Karlsruhe U. /Sao Paulo U. /LIP, Coimbra /Brussels U. /Sao Paulo U., Guaratingueta /Northwestern U. /Oxford U. /Orsay, LPT /Athens U. /Lisbon U.
2008-03-07
This chapter of the report of the 'Flavour in the era of LHC' workshop discusses flavor related issues in the production and decays of heavy states at LHC, both from the experimental side and from the theoretical side. We review top quark physics and discuss flavor aspects of several extensions of the Standard Model, such as supersymmetry, little Higgs model or models with extra dimensions. This includes discovery aspects as well as measurement of several properties of these heavy states. We also present public available computational tools related to this topic.
$\\pi K$ Scattering in Three Flavour ChPT
Bijnens, Johan; Dhonte, Pierre; Talavera, Pere
2004-01-01
We present the scattering lengths for the $\\pi K$ processes in the three flavour Chiral Perturbation Theory (ChPT) framework at next-to-next-to-leading order (NNLO). The calculation has been performed analytically but we only include analytical results for the dependence on the low-energy constants (LECs) at NNLO due to the size of the expressions. These results, together with resonance estimates of the NNLO LECs are used to obtain constraints on the Zweig rule suppressed LECs at NLO, $L_4^r$...
Heavy Flavour Production and Properties at ATLAS and CMS
Barberis, Dario; The ATLAS collaboration
2016-01-01
Recent results by the ATLAS and CMS experiments at LHC are presented on the production and properties of heavy-flavour states. In the charm sector, cross-sections for the prompt and non-prompt production of J/psi and psi’ are presented, as well as the production of open charm states. The b-quark fragmentation, B± production cross-section and several B-meson decay properties are also studied. The used data include LHC Run 1 (at a centre-of-mass energy of 7 and 8 TeV) and also Run 2 (13 TeV) samples collected in 2015.
Baryons in 2+1 flavour domain wall QCD
Antonio, D. J.; Bowler, K. C.; Boyle, P. A.; Clark, M A; Joó, B.; Kennedy, A. D.; Kenway, R. D.; Maynard, C. M.; Tweedie, R. J.; Yamaguchi, A; RBC; collaborations, UKQCD
2005-01-01
We present results for some of the light baryon masses and their excited states in 2+1 flavour domain wall QCD. We considered several lattice spacings, with the DBW2 and Iwasaki gauge actions and different sea quark masses on a volume of $16^3\\times32$ and a fifth dimension of size 8. All data were generated on the QCDOC machines. Despite large residual massses and a limited number of sea quark mass values with which to perform chiral extrapolations, our results are in reasonable agreement wi...
Approaching the chiral point in two-flavour lattice simulations
International Nuclear Information System (INIS)
We investigate the behaviour of the pion decay constant and the pion mass in two-flavour lattice QCD, with the physical and chiral points as ultimate goal. Measurements come from the ensembles generated by the CLS initiative using the O(a)-improved Wilson formulation, with lattice spacing down to about 0.05 fermi and pion masses as low as 190 MeV. The applicability of SU(2) chiral perturbation theory is investigated, and various functional forms, and their range of validity, are compared. The physical scale is set through the kaon decay constant, whose measurement is enabled by inserting a third, heavier valence strange quark.
Approaching the chiral point in two-flavour lattice simulations
Lottini, Stefano
2014-01-01
We investigate the behaviour of the pion decay constant and the pion mass in two-flavour lattice QCD, with the physical and chiral points as ultimate goal. Measurements come from the ensembles generated by the CLS initiative using the O(a)-improved Wilson formulation, with lattice spacing down to about 0.05 fermi and pion masses as low as 190 MeV. The applicability of SU(2) chiral perturbation theory is investigated, and various functional forms, and their range of validity, are compared. The physical scale is set through the kaon decay constant, whose measurement is enabled by inserting a third, heavier valence strange quark.
Summary of hints for new physics from (quark) flavour physics
Zwicky, Roman(Higgs Centre for Theoretical Physics, School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ, Scotland, United Kingdom)
2008-01-01
Recently two hints for new physics have emerged: The B_s mixing phase phi_s and the rate of D_s -> (mu,tau) nu exposing a discrepancy of \\sim 3 sigma and 3.8 sigma deviation from the Standard Model respectively. Moreover the difference of the CP asymmetries in B -> K pi between the charged and neutral modes is at the 5.3 sigma level which is somewhat larger than expected. New physics in phi_s or A_CP(B -> K pi) would be in contradiction with the minimal flavour violation hypothesis. ...
Search for lepton flavour violation in Z0 decays
International Nuclear Information System (INIS)
We have searched for lepton flavour violation in Z0 boson decays into lepton pairs, Z0→μτ, Z0→eτ, and Z-→eμ. The data sample is based on an integrated luminosity of 10.4 pb-1 corresponding to 370 000 Z0's produced. We obtain upper limits on the branching ratios of 4.8x10-5 for the μτ, 3.4x10-5 for the eτ and 2.4x10-5 for the eμ decay modes at the 95% confidence level. (orig.)
Wang, Zong-Min; Lu, Zhen-Ming; Shi, Jin-Song; Xu, Zheng-Hong
2016-01-01
Multispecies solid-state fermentation (MSSF), a natural fermentation process driven by reproducible microbiota, is an important technique to produce traditional fermented foods. Flavours, skeleton of fermented foods, was mostly produced by microbiota in food ecosystem. However, the association between microbiota and flavours and flavour-producing core microbiota are still poorly understood. Here, acetic acid fermentation (AAF) of Zhenjiang aromatic vinegar was taken as a typical case of MSSF. The structural and functional dynamics of microbiota during AAF process was determined by metagenomics and favour analyses. The dominant bacteria and fungi were identified as Acetobacter, Lactobacillus, Aspergillus, and Alternaria, respectively. Total 88 flavours including 2 sugars, 9 organic acids, 18 amino acids, and 59 volatile flavours were detected during AAF process. O2PLS-based correlation analysis between microbiota succession and flavours dynamics showed bacteria made more contribution to flavour formation than fungi. Seven genera including Acetobacter, Lactobacillus, Enhydrobacter, Lactococcus, Gluconacetobacer, Bacillus and Staphylococcus were determined as functional core microbiota for production of flavours in Zhenjiang aromatic vinegar, based on their dominance and functionality in microbial community. This study provides a perspective for bridging the gap between the phenotype and genotype of ecological system, and advances our understanding of MSSF mechanisms in Zhenjiang aromatic vinegar. PMID:27241188
Wang, Zong-Min; Lu, Zhen-Ming; Shi, Jin-Song; Xu, Zheng-Hong
2016-01-01
Multispecies solid-state fermentation (MSSF), a natural fermentation process driven by reproducible microbiota, is an important technique to produce traditional fermented foods. Flavours, skeleton of fermented foods, was mostly produced by microbiota in food ecosystem. However, the association between microbiota and flavours and flavour-producing core microbiota are still poorly understood. Here, acetic acid fermentation (AAF) of Zhenjiang aromatic vinegar was taken as a typical case of MSSF. The structural and functional dynamics of microbiota during AAF process was determined by metagenomics and favour analyses. The dominant bacteria and fungi were identified as Acetobacter, Lactobacillus, Aspergillus, and Alternaria, respectively. Total 88 flavours including 2 sugars, 9 organic acids, 18 amino acids, and 59 volatile flavours were detected during AAF process. O2PLS-based correlation analysis between microbiota succession and flavours dynamics showed bacteria made more contribution to flavour formation than fungi. Seven genera including Acetobacter, Lactobacillus, Enhydrobacter, Lactococcus, Gluconacetobacer, Bacillus and Staphylococcus were determined as functional core microbiota for production of flavours in Zhenjiang aromatic vinegar, based on their dominance and functionality in microbial community. This study provides a perspective for bridging the gap between the phenotype and genotype of ecological system, and advances our understanding of MSSF mechanisms in Zhenjiang aromatic vinegar.
Heavy flavours production in deeply inelastic scattering and gluon density in the proton
Balbi, P
2002-01-01
Heavy flavours production in e-p DIS is studied at intermediate values of the transferred four-momentum square, under the assumption of boson-gluon-fusion mechanism dominance (no intrinsic heavy flavours contributions). In this framework different expressions for the splitting functions in the gluon density evolution equation, with respect to the standard (DGLAP) ones, are explicitly derived.
“Popcorn worker’s lung” in Britain in a man making potato crisp flavouring
Hendrick, D J
2009-01-01
This case involves a 36 year old non-smoker who worked in a factory producing food flavourings for potato crisps. He developed exertional breathlessness associated with fixed airway obstruction shortly after an uncharacteristically high exposure to the food flavouring chemical diacetyl. Unfortunately, even though he was removed from further exposure to this agent, his symptoms and spirometry did not improve.
Aprea, E.; Biasioli, F.; Gasperi, F.; Tilmann, M.D.; Ruth, van S.M.
2006-01-01
The interaction of oral processing protocols and food texture on in vivo flavour release was evaluated by nose-space analysis. Nose-space analysis was carried out by proton transfer reaction mass spectrometry, and strawberry-flavoured custards were prepared with 0.1% (w/w) and 1.0% (w/w) carboxymeth
Searches for new physics with lepton flavours and multi-lepton final states in ATLAS
Madar, Romain; The ATLAS collaboration
2015-01-01
Lepton flavours and multi-lepton signatures are powerful probes to new physics. ATLAS searches for lepton flavour violating decays of (beyond) the SM particles, leptoquarks, heavy leptons/neutrinos as well as for new phenomena in multi-lepton/photon final states are summarized in this talk. First LHC Run-2 results will be included if available.
Wang, Zong-Min; Lu, Zhen-Ming; Shi, Jin-Song; Xu, Zheng-Hong
2016-01-01
Multispecies solid-state fermentation (MSSF), a natural fermentation process driven by reproducible microbiota, is an important technique to produce traditional fermented foods. Flavours, skeleton of fermented foods, was mostly produced by microbiota in food ecosystem. However, the association between microbiota and flavours and flavour-producing core microbiota are still poorly understood. Here, acetic acid fermentation (AAF) of Zhenjiang aromatic vinegar was taken as a typical case of MSSF. The structural and functional dynamics of microbiota during AAF process was determined by metagenomics and favour analyses. The dominant bacteria and fungi were identified as Acetobacter, Lactobacillus, Aspergillus, and Alternaria, respectively. Total 88 flavours including 2 sugars, 9 organic acids, 18 amino acids, and 59 volatile flavours were detected during AAF process. O2PLS-based correlation analysis between microbiota succession and flavours dynamics showed bacteria made more contribution to flavour formation than fungi. Seven genera including Acetobacter, Lactobacillus, Enhydrobacter, Lactococcus, Gluconacetobacer, Bacillus and Staphylococcus were determined as functional core microbiota for production of flavours in Zhenjiang aromatic vinegar, based on their dominance and functionality in microbial community. This study provides a perspective for bridging the gap between the phenotype and genotype of ecological system, and advances our understanding of MSSF mechanisms in Zhenjiang aromatic vinegar. PMID:27241188
DEFF Research Database (Denmark)
Beltoft, Vibe Meister; Binderup, Mona-Lise; Frandsen, Henrik Lauritz;
the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered. Adequate specifications including complete purity criteria and identity for the materials of commerce have been provided for all 24 candidate substances....
Dynamical Symmetries in Classical Mechanics
Boozer, A. D.
2012-01-01
We show how symmetries of a classical dynamical system can be described in terms of operators that act on the state space for the system. We illustrate our results by considering a number of possible symmetries that a classical dynamical system might have, and for each symmetry we give examples of dynamical systems that do and do not possess that…
Broken symmetries in field theory
Kok, Mark Okker de
2008-01-01
The thesis discusses the role of symmetries in Quantum Field Theory. Quantum Field Theory is the mathematical framework to describe the physics of elementary particles. A symmetry here means a transformation under which the model at hand is invariant. Three types of symmetry are distinguished: 1. In
Charge independence and charge symmetry
Miller, G A; Miller, Gerald A; van Oers, Willem T H
1994-01-01
Charge independence and charge symmetry are approximate symmetries of nature, violated by the perturbing effects of the mass difference between up and down quarks and by electromagnetic interactions. The observations of the symmetry breaking effects in nuclear and particle physics and the implications of those effects are reviewed.
Scattering matrices with block symmetries
Życzkowski, Karol
1997-01-01
Scattering matrices with block symmetry, which corresponds to scattering process on cavities with geometrical symmetry, are analyzed. The distribution of transmission coefficient is computed for different number of channels in the case of a system with or without the time reversal invariance. An interpolating formula for the case of gradual time reversal symmetry breaking is proposed.
Emergence of Symmetries from Entanglement
CERN. Geneva
2016-01-01
Maximal Entanglement appears to be a key ingredient for the emergence of symmetries. We first illustrate this phenomenon using two examples: the emergence of conformal symmetry in condensed matter systems and the relation of tensor networks to holography. We further present a Principle of Maximal Entanglement that seems to dictate to a large extend the structure of gauge symmetry.
Asymmetry, Symmetry and Beauty
Directory of Open Access Journals (Sweden)
Abbe R. Kopra
2010-07-01
Full Text Available Asymmetry and symmetry coexist in natural and human processes. The vital role of symmetry in art has been well demonstrated. This article highlights the complementary role of asymmetry. Further we show that the interaction of asymmetric action (recursion and symmetric opposition (sinusoidal waves are instrumental in generating creative features (relatively low entropy, temporal complexity, novelty (less recurrence in the data than in randomized copies and complex frequency composition. These features define Bios, a pattern found in musical compositions and in poetry, except for recurrence instead of novelty. Bios is a common pattern in many natural and human processes (quantum processes, the expansion of the universe, gravitational waves, cosmic microwave background radiation, DNA, physiological processes, animal and human populations, and economic time series. The reduction in entropy is significant, as it reveals creativity and contradicts the standard claim of unavoidable decay towards disorder. Artistic creations capture fundamental features of the world.
Cluster Symmetries and Dynamics
Directory of Open Access Journals (Sweden)
Freer Martin
2016-01-01
Full Text Available Many light nuclei display behaviour that indicates that rather than behaving as an A-body systems, the protons and neutrons condense into clusters. The α-particle is the most obvious example of such clustering. This contribution examines the role of such α-clustering on the structure, symmetries and dynamics of the nuclei 8Be, 12C and 16O, recent experimental measurements and future perspectives.
International Nuclear Information System (INIS)
Music and Physics are very close because of the symmetry that appears in music. A periodic wave is what music really is, and there is a field of Physics devoted to waves researching. The different musical scales are the base of all kind of music. This article tries to show how this musical scales are made, how the consonance is the base of many of them and how symmetric they are.
Energy Technology Data Exchange (ETDEWEB)
Herrero, O F, E-mail: o.f.herrero@hotmail.co [Conservatorio Superior de Musica ' Eduardo Martinez Torner' Corrada del Obispo s/n 33003 - Oviedo - Asturias (Spain)
2010-06-01
Music and Physics are very close because of the symmetry that appears in music. A periodic wave is what music really is, and there is a field of Physics devoted to waves researching. The different musical scales are the base of all kind of music. This article tries to show how this musical scales are made, how the consonance is the base of many of them and how symmetric they are.
A left-right symmetric flavor symmetry model
International Nuclear Information System (INIS)
We discuss flavor symmetries in left-right symmetric theories. We show that such frameworks are a different environment for flavor symmetry model building compared to the usually considered cases. This does not only concern the need to obey the enlarged gauge structure, but also more subtle issues with respect to residual symmetries. Furthermore, if the discrete left-right symmetry is charge conjugation, potential inconsistencies between the flavor and charge conjugation symmetries should be taken care of. In our predictive model based on A4 we analyze the correlations between the smallest neutrino mass, the atmospheric mixing angle and the Dirac CP phase, the latter prefers to lie around maximal values. There is no lepton flavor violation from the Higgs bi-doublet. (orig.)
A left-right symmetric flavor symmetry model
Rodejohann, Werner
2015-01-01
We discuss flavor symmetries in left-right symmetric theories. We show that such frameworks are a different environment for flavor symmetry model building compared to the usually considered cases. This does not only concern the need to obey the enlarged gauge structure, but also more subtle issues with respect to residual symmetries. Furthermore, if the discrete left-right symmetry is charge conjugation, potential inconsistencies between the flavor and charge conjugation symmetries should be taken care of. In our predictive model based on $A_4$ we analyze the correlations between the smallest neutrino mass, the atmospheric mixing angle and the Dirac CP phase, the latter prefers to lie around maximal values. There is no lepton flavor violation from the Higgs bi-doublet.
A left-right symmetric flavor symmetry model
Rodejohann, Werner; Xu, Xun-Jie
2016-03-01
We discuss flavor symmetries in left-right symmetric theories. We show that such frameworks are a different environment for flavor symmetry model building compared to the usually considered cases. This does not only concern the need to obey the enlarged gauge structure, but also more subtle issues with respect to residual symmetries. Furthermore, if the discrete left-right symmetry is charge conjugation, potential inconsistencies between the flavor and charge conjugation symmetries should be taken care of. In our predictive model based on A_4 we analyze the correlations between the smallest neutrino mass, the atmospheric mixing angle and the Dirac CP phase, the latter prefers to lie around maximal values. There is no lepton flavor violation from the Higgs bi-doublet.
Christodoulides, Demetrios
2015-03-01
Interest in complex Hamiltonians has been rekindled after the realization that a wide class of non-Hermitian Hamiltonians can have entirely real spectra as long as they simultaneously respect parity and time reversal operators. In non-relativistic quantum mechanics, governed by the Schrödinger equation, a necessary but not sufficient condition for PT symmetry to hold is that the complex potential should involve real and imaginary parts which are even and odd functions of position respectively. As recently indicated, optics provides a fertile ground to observe and utilize notions of PT symmetry. In optics, the refractive index and gain/loss profiles play the role of the real and imaginary parts of the aforementioned complex potentials. As it has been demonstrated in several studies, PT-symmetric optical structures can exhibit peculiar properties that are otherwise unattainable in traditional Hermitian (conservative) optical settings. Among them, is the possibility for breaking this symmetry through an abrupt phase transition, band merging effects and unidirectional invisibility. Here we review recent developments in the field of -symmetric optics.
Diet and growth effects in panel assessment of sheepmeat odour and flavour.
Rousset-Akrim, S; Young, O A; Berdagué, J L
1997-02-01
The effects of sheep age and diet on several odours and flavours are described. Ram lambs raised on ewe's milk then a corn-based diet were compared with lambs raised on milk and a pasture of grass/clover, six treatments in all. A seventh treatment comprised very old ewes maintained on pasture. Fat and lean from forequarters was minced and cooked together. Cooked lean was assessed for intensity by a sensory panel for 10 flavour attributes. Four showed significant (P sheepmeat', 'animal', 'liver', and 'poultry'. Sheepmeat flavour was highest in the slow-grown pasture-fed lambs. Animal flavour-the flavour associated with the odour of confined livestock-showed a similar pattern with treatment. Liver flavour was highest in ewe meat, and the biochemical origin of this flavour is discussed. Eleven related odour attributes were assessed on the rendered fat with a novel olfactometer. Five attributes showed highly significant treatment effects for intensity (P sheepmeat odours showed a similar distribution to the equivalent flavours; likewise cabbage and rancid odours were associated with the two slow-grown pasture treatments. A comparison of the odour and flavour statistics showed that the sense of smell was the more discriminating in sheepmeat assessment, and also confirmed that fat was the true source of sheepmeat odour/flavour. In respect of sheepmeat production for effective marketing, the data showed that at 90 days, a pastoral diet resulted in slightly enhanced odours when compared with a corn-based diet. By 215 days, however, many undesirable odours were exacerbated. Since these older rams were more sexually developed, a sex rather than an age effect could not be excluded. Rendered fat from this work was further used in a companion study (Yang et al., 1997. Meat Sci., 45, 183-200) in an attempt to link individual volatile compounds to odour attributes. PMID:22061301
Changes in flavour and taste of irradiated coffee beans
International Nuclear Information System (INIS)
The possibility of changes in the smell and taste of coffee from beans submitted to irradiation for preservation is a significant gap in the programme devoted to increasing the product life time with such a process. Therefore, the main objective of the paper was to evaluate changes in aroma and flavour that can be noticed by the consumer. Coffee beans were given disinfestation doses of 50krad, producing an insect mortality rate of 98.33% +-2.89 in Araecerus fasciculatus (adult stage). The samples, provided by IBC, were from the same crop and free from pesticides. Some of the material was kept by that Institute for organoleptic tests. The remainder was sent to the National Institute of Technology for gas-chromatographic analysis. Should any significant changes be noticed, it could be assumed that the gamma-irradiation process would be rejected by the consumer. However, no significant change was observed in the most important characteristics, flavour and aroma, that might induce the consumer to reject irradiated coffee beans. (author)
Changes in Flavour and Taste of Irradiated Coffee Beans
International Nuclear Information System (INIS)
The possibility of changes in the smell and taste of coffee from beans submitted to irradiation for preservation is a significant gap in the programme devoted to increasing the product life time with such a process. Therefore, the main objective of the paper was to evaluate changes in aroma and flavour that can be noticed by the consumer. Coffee beans were given disinfestation doses of 50 krad, producing an insect mortality rate of 98.33% ± 2.89 in Araecerus fasciculatus (adult stage). The samples, provided by IBC, were from the same crop and free from pesticides. Some of the material was kept by that Institute for organoleptic tests. The remainder was sent to the National Institute of Technology for gas-chromatographic analysis. Should any significant changes be noticed, it could be assumed that the gamma-irradiation process would be rejected by the consumer. However, no significant change was observed in the most important characteristics, flavour and aroma, that might induce the consumer to reject irradiated coffee beans. (author)
Flavour violating gluino three-body decays at LHC
Energy Technology Data Exchange (ETDEWEB)
Bartl, A.; Ginina, E. [Wien Univ. (Austria). Fakultaet fuer Physik; Eberl, H.; Majerotto, W. [Oesterreichische Akademie der Wissenschaften, Vienna (Austria). Inst. fuer Hochenergiephysik; Herrmann, B. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Hidaka, K [Tokyo Gakugei Univ., Koganei (Japan). Dept. of Physics; Porod, W. [Wuerzburg Univ. (Germany). Inst. fuer Theoretische Physik und Astrophysik
2011-07-15
We study the effect of squark generation mixing on gluino production and decays at LHC in the Minimal Supersymmetric Standard Model (MSSM) for the case that the gluino is lighter than all squarks and dominantly decays into three particles, g {yields} q q {chi}{sup 0}{sub k}, q anti q'{chi}{sup {+-}}{sub l}. We assume mixing between the second and the third squark generations in the up-type and down-type squark sectors. We show that this mixing can lead to very large branching ratios of the quark-flavour violating gluino threebody decays despite the strong constraints on quark-flavour violation (QFV) from the experimental data on B mesons. We also show that the QFV gluino decay branching ratios are very sensitive not only to the generation mixing in the squark sector, but also to the parameters of the neutralino and chargino sectors. We show that the branching ratio of the QFV gluino decay g {yields} c anti t(anti ct) anti {chi}{sup 0}{sub 1} can go up to {approx} 40%. Analogously, that of the QFV decay g {yields} s anti b(anti sb){chi}{sup 0}{sub 1} can reach {approx} 35%. We find that the rates of the resulting QFV signatures, such as pp{yields} tt anti c anti cE{sup mis}{sub T}, can be significant at LHC. This could have an important influence on the gluino searches at LHC. (orig.)
Light flavour hadron production in the ALICE experiment at LHC
Directory of Open Access Journals (Sweden)
Badalà Angela
2016-01-01
Full Text Available Unique among the LHC experiments, ALICE has excellent particle identification capabilities for the measurement of light-flavour hadrons. A large number of hadron species from pions to multi-strange baryons and light nuclei have been measured over a large transverse momentum region. The measurement of the production of these particles is a valuable tool to study the properties of the medium formed in heavy-ion collisions. In particular they give information on the collective phenomena of the fireball, on the parton energy loss in the hot QCD medium and on the hadronization mechanisms such as recombination and statistical hadronization. The measurements in pp and in p-nucleus collisions provide the necessary baseline for heavy-ion data and help to investigate the effects of the ordinary nuclear matter. In this paper some of the main ALICE results on identified light-flavour hadron production in Pb–Pb collisions at √sNN = 2.76 TeV and p–Pb collisions at √sNN = 5.02 TeV will be presented.
Light flavour hadron production in the ALICE experiment at LHC
Badalà, Angela
2016-05-01
Unique among the LHC experiments, ALICE has excellent particle identification capabilities for the measurement of light-flavour hadrons. A large number of hadron species from pions to multi-strange baryons and light nuclei have been measured over a large transverse momentum region. The measurement of the production of these particles is a valuable tool to study the properties of the medium formed in heavy-ion collisions. In particular they give information on the collective phenomena of the fireball, on the parton energy loss in the hot QCD medium and on the hadronization mechanisms such as recombination and statistical hadronization. The measurements in pp and in p-nucleus collisions provide the necessary baseline for heavy-ion data and help to investigate the effects of the ordinary nuclear matter. In this paper some of the main ALICE results on identified light-flavour hadron production in Pb-Pb collisions at √sNN = 2.76 TeV and p-Pb collisions at √sNN = 5.02 TeV will be presented.
Leading logarithms in N-flavour mesonic Chiral Perturbation Theory
International Nuclear Information System (INIS)
We extend earlier work on leading logarithms in the massive nonlinear O(n) sigma model to the case of SU(N)×SU(N)/SU(N) which coincides with mesonic Chiral Perturbation Theory for N flavours of light quarks. We discuss the leading logarithms for the mass and decay constant to six loops and for the vacuum expectation value 〈q¯q〉 to seven loops. For dynamical quantities the expressions grow extremely large much faster such that we only quote the leading logarithms to five loops for the vector and scalar form factor and for meson–meson scattering. The last quantity we consider is the vector–vector to meson–meson amplitude where we quote results up to four loops for a subset of quantities, in particular for the pion polarizabilities. As a side result we provide an elementary proof that the factors of N appearing at each loop order are odd or even depending on the order and the remaining traces over external flavours
Directory of Open Access Journals (Sweden)
Vladan Nikolić
2015-02-01
Full Text Available The idea of construction of twin buildings is as old as architecture itself, and yet there is hardly any study emphasizing their specificity. Most frequently there are two objects or elements in an architectural composition of “twins” in which there may be various symmetry relations, mostly bilateral symmetries. The classification of “twins” symmetry in this paper is based on the existence of bilateral symmetry, in terms of the perception of an observer. The classification includes both, 2D and 3D perception analyses. We start analyzing a pair of twin buildings with projection of the architectural composition elements in 2D picture plane (plane of the composition and we distinguish four 2D keyframe cases based on the relation between the bilateral symmetry of the twin composition and the bilateral symmetry of each element. In 3D perception for each 2D keyframe case there are two sub-variants, with and without a symmetry plane parallel to the picture plane. The bilateral symmetry is dominant if the corresponding symmetry plane is orthogonal to the picture plane. The essence of the complete classification is relation between the bilateral (dominant symmetry of the architectural composition and the bilateral symmetry of each element of that composition.
Weak complementarity from discrete symmetries
Merlo, Luca
2009-01-01
The neutrino oscillation data find a good approximation in the so-called tri-bimaximal pattern. Recently a paper appeared showing that also the bimaximal pattern, which is already ruled out by the measurements, could be a very good starting point in order to describe the lepton mixing. In this paper I review both the flavour structures and then I present an explicit flavour model based on the discrete group S4, in which the PMNS mixing matrix is of the bimaximal form in first approximation and after it receives corrections which bring it in agreement with the data. The resulting spectrum of light neutrinos shows a moderate normal hierarchy and is compatible, within large ambiguities, with the constraints from leptogenesis as an explanation of the baryon asymmetry in the Universe.
Yale, Paul B
2012-01-01
This book is an introduction to the geometry of Euclidean, affine, and projective spaces with special emphasis on the important groups of symmetries of these spaces. The two major objectives of the text are to introduce the main ideas of affine and projective spaces and to develop facility in handling transformations and groups of transformations. Since there are many good texts on affine and projective planes, the author has concentrated on the n-dimensional cases.Designed to be used in advanced undergraduate mathematics or physics courses, the book focuses on ""practical geometry,"" emphasi
Surface defects and symmetries
Fuchs, Jürgen; Schweigert, Christoph
2015-04-01
In quantum field theory, defects of various codimensions are natural ingredients and carry a lot of interesting information. In this contribution we concentrate on topological quantum field theories in three dimensions, with a particular focus on Dijkgraaf-Witten theories with abelian gauge group. Surface defects in Dijkgraaf-Witten theories have applications in solid state physics, topological quantum computing and conformal field theory. We explain that symmetries in these topological field theories are naturally defined in terms of invertible topological surface defects and are thus Brauer-Picard groups.
Baldo, M.; Burgio, G.F.
2016-01-01
The nuclear symmetry energy characterizes the variation of the binding energy as the neutron to proton ratio of a nuclear system is varied. This is one of the most important features of nuclear physics in general, since it is just related to the two component nature of the nuclear systems. As such it is one of the most relevant physical parameters that affect the physics of many phenomena and nuclear processes. This review paper presents a survey of the role and relevance of the nuclear symme...
On the stability of the parity symmetry of the scotogenic model
Energy Technology Data Exchange (ETDEWEB)
Merle, Alexander; Platscher, Moritz [Max-Planck-Institut fuer Physik, Foehringer Ring 6, 80805 Muenchen (Germany)
2015-07-01
We study the 1-loop structure of the scotogenic model - a simple extension of the SM by an inert scalar doublet and heavy singlet Majorana neutrino fields, all having odd charge under a Z{sub 2} symmetry. This model can account for a variety of phenomena, such as small neutrino masses, lepton flavour violation and Dark Matter. In addition to the well-known theoretical and experimental bounds on the model's scalar sector, we consider the issue of naturalness which arises as the heavy Majorana fermions are coupled to the inert doublet and give rise to potentially large negative corrections to the corresponding scalar mass parameter. Thus, the right choice of model parameters is indispensable to keep the central parity symmetry intact.
Accidental permutation symmetries as a test for Grand Unification: the supersymmetric $SU(5)$ case
Fichet, Sylvain
2016-01-01
Unification of matter fields implies the existence of accidental permutation symmetries, which potentially remain immune to large quantum corrections up to the TeV scale. We investigate the case of a supersymmetric $SU(5)$ grand unified theory, where such a permutation symmetry is present in the up-type squark sector. We present a variety of tests allowing to challenge the $SU(5)$ hypothesis based on the observation of squarks at the LHC. These tests appear as relations among observables involving flavour-violating or chirality-flipping decays of squarks. Moreover, they rely on top-polarimetry and charm-tagging. As an example, we discuss the application to the scenario of Natural Supersymmetry, while more examples can be found in the related journal publications.
Role of anterior piriform cortex in the acquisition of conditioned flavour preference.
Mediavilla, Cristina; Martin-Signes, Mar; Risco, Severiano
2016-01-01
Flavour aversion learning (FAL) and conditioned flavour preference (CFP) facilitate animal survival and play a major role in food selection, but the neurobiological mechanisms involved are not completely understood. Neuroanatomical bases of CFP were examined by using Fos immunohistochemistry to record neuronal activity. Rats were trained over eight alternating one-bottle sessions to acquire a CFP induced by pairing a flavour with saccharin (grape was CS+ in Group 1; cherry in Group 2; in Group 3, grape/cherry in half of animals; Group 4, grape/cherry in water). Animals were offered the grape flavour on the day immediately after the training and their brains were processed for c-Fos. Neurons evidencing Fos-like immunoreactivity were counted in the infralimbic cortex, nucleus accumbens core, and anterior piriform cortex (aPC). Analysis showed a significantly larger number of activated cells after learning in the aPC alone, suggesting that the learning process might have produced a change in this cortical region. Ibotenic lesions in the aPC blocked flavour-taste preference but did not interrupt flavour-toxin FAL by LiCl. These data suggest that aPC cells may be involved in the formation of flavour preferences and that the integrity of this region may be specifically necessary for the acquisition of a CFP. PMID:27624896
New aspects of flavour model building in supersymmetric grand unification
Energy Technology Data Exchange (ETDEWEB)
Spinrath, Martin
2010-05-19
We derive predictions for Yukawa coupling ratios within Grand Unified Theories generated from operators with mass dimension four and five. These relations are a characteristic property of unified flavour models and can reduce the large number of free parameters related to the flavour sector of the Standard Model. The Yukawa couplings of the down-type quarks and charged leptons are affected within supersymmetric models by tan {beta}-enhanced threshold corrections which can be sizeable if tan {beta} is large. In this case their careful inclusion in the renormalisation group evolution is mandatory. We analyse these corrections and give simple analytic expressions and numerical estimates for them. The threshold corrections sensitively depend on the soft supersymmetry breaking parameters. Especially, they determine the overall sign of the corrections and therefore if the affected Yukawa couplings are enhanced or suppressed. In the minimal supersymmetric extension of the Standard Model many free parameters are introduced by supersymmetry breaking about which we make some plausible assumptions in our first simplified approach. In a second, more sophisticated approach we use three common breaking schemes in which all the soft breaking parameters at the electroweak scale can be calculated from only a handful of parameters. Within the second approach, we apply various phenomenological constraints on the supersymmetric parameters and find in this way new viable Yukawa coupling relations, for example y{sub {mu}}/y{sub s}=9/2 or 6 or y{sub {tau}}/y{sub b}=3/2 in SU(5). Furthermore, we study a special class of quark mass matrix textures for small tan {beta} where {theta}{sup u}{sub 13}={theta}{sup d}{sub 13}=0. We derive sum rules for the quark mixing parameters and find a simple relation between the two phases {delta}{sup u}{sub 12} and {delta}{sup d}{sub 12} and the right unitarity triangle angle {alpha} which suggests a simple phase structure for the quark mass matrices where
Directory of Open Access Journals (Sweden)
Caroline Clouard
Full Text Available This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d. infusions of 15% glucose (F(Glu, lithium chloride (F(LiCl, or saline (control treatment, F(NaCl. One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to check the acquisition of a conditioned flavour preference or aversion. In between, the anaesthetised pigs were subjected to three (18FDG PET brain imaging coupled with an olfactogustatory stimulation with the conditioned flavours. During conditioning, the pigs spent more time lying inactive, and investigated their environment less after the F(LiCl than the F(NaCl or F(Glu meals. During the two-choice tests performed one and five weeks later, the F(NaCl and F(Glu foods were significantly preferred over the F(LICl food even in the absence of i.d. infusions. Surprisingly, the F(NaCl food was also preferred over the F(Glu food during the first test only, suggesting that, while LiCl i.d. infusions led to a strong flavour aversion, glucose infusions failed to induce flavour preference. As for brain imaging results, exposure to aversive or less preferred flavours triggered global deactivation of the prefrontal cortex, specific activation of the posterior cingulate cortex, as well as asymmetric brain responses in the basal nuclei and the temporal gyrus. In conclusion, postingestive visceral stimuli can modulate the flavour/food hedonism and further feeding choices. Exposure to flavours with different hedonic values induced metabolism differences in neural circuits known to be involved in humans in the characterization of food palatability, feeding motivation, reward expectation, and more generally in the regulation of food intake.
Directory of Open Access Journals (Sweden)
Angel Garrido
2011-01-01
Full Text Available In this paper, we analyze a few interrelated concepts about graphs, such as their degree, entropy, or their symmetry/asymmetry levels. These concepts prove useful in the study of different types of Systems, and particularly, in the analysis of Complex Networks. A System can be defined as any set of components functioning together as a whole. A systemic point of view allows us to isolate a part of the world, and so, we can focus on those aspects that interact more closely than others. Network Science analyzes the interconnections among diverse networks from different domains: physics, engineering, biology, semantics, and so on. Current developments in the quantitative analysis of Complex Networks, based on graph theory, have been rapidly translated to studies of brain network organization. The brain's systems have complex network features—such as the small-world topology, highly connected hubs and modularity. These networks are not random. The topology of many different networks shows striking similarities, such as the scale-free structure, with the degree distribution following a Power Law. How can very different systems have the same underlying topological features? Modeling and characterizing these networks, looking for their governing laws, are the current lines of research. So, we will dedicate this Special Issue paper to show measures of symmetry in Complex Networks, and highlight their close relation with measures of information and entropy.
Bootstrap Dynamical Symmetry Breaking
Directory of Open Access Journals (Sweden)
Wei-Shu Hou
2013-01-01
Full Text Available Despite the emergence of a 125 GeV Higgs-like particle at the LHC, we explore the possibility of dynamical electroweak symmetry breaking by strong Yukawa coupling of very heavy new chiral quarks Q . Taking the 125 GeV object to be a dilaton with suppressed couplings, we note that the Goldstone bosons G exist as longitudinal modes V L of the weak bosons and would couple to Q with Yukawa coupling λ Q . With m Q ≳ 700 GeV from LHC, the strong λ Q ≳ 4 could lead to deeply bound Q Q ¯ states. We postulate that the leading “collapsed state,” the color-singlet (heavy isotriplet, pseudoscalar Q Q ¯ meson π 1 , is G itself, and a gap equation without Higgs is constructed. Dynamical symmetry breaking is affected via strong λ Q , generating m Q while self-consistently justifying treating G as massless in the loop, hence, “bootstrap,” Solving such a gap equation, we find that m Q should be several TeV, or λ Q ≳ 4 π , and would become much heavier if there is a light Higgs boson. For such heavy chiral quarks, we find analogy with the π − N system, by which we conjecture the possible annihilation phenomena of Q Q ¯ → n V L with high multiplicity, the search of which might be aided by Yukawa-bound Q Q ¯ resonances.
Applications of chiral symmetry
Energy Technology Data Exchange (ETDEWEB)
Pisarski, R.D.
1995-03-01
The author discusses several topics in the applications of chiral symmetry at nonzero temperature. First, where does the rho go? The answer: up. The restoration of chiral symmetry at a temperature T{sub {chi}} implies that the {rho} and a{sub 1} vector mesons are degenerate in mass. In a gauged linear sigma model the {rho} mass increases with temperature, m{sub {rho}}(T{sub {chi}}) > m{sub {rho}}(0). The author conjectures that at T{sub {chi}} the thermal {rho} - a{sub 1}, peak is relatively high, at about {approximately}1 GeV, with a width approximately that at zero temperature (up to standard kinematic factors). The {omega} meson also increases in mass, nearly degenerate with the {rho}, but its width grows dramatically with temperature, increasing to at least {approximately}100 MeV by T{sub {chi}}. The author also stresses how utterly remarkable the principle of vector meson dominance is, when viewed from the modern perspective of the renormalization group. Secondly, he discusses the possible appearance of disoriented chiral condensates from {open_quotes}quenched{close_quotes} heavy ion collisions. It appears difficult to obtain large domains of disoriented chiral condensates in the standard two flavor model. This leads to the last topic, which is the phase diagram for QCD with three flavors, and its proximity to the chiral critical point. QCD may be very near this chiral critical point, and one might thereby generated large domains of disoriented chiral condensates.
Rosensteel, George
1995-01-01
Riemann ellipsoids model rotating galaxies when the galactic velocity field is a linear function of the Cartesian coordinates of the galactic masses. In nuclear physics, the kinetic energy in the linear velocity field approximation is known as the collective kinetic energy. But, the linear approximation neglects intrinsic degrees of freedom associated with nonlinear velocity fields. To remove this limitation, the theory of symplectic dynamical symmetry is developed for classical systems. A classical phase space for a self-gravitating symplectic system is a co-adjoint orbit of the noncompact group SP(3,R). The degenerate co-adjoint orbit is the 12 dimensional homogeneous space Sp(3,R)/U(3), where the maximal compact subgroup U(3) is the symmetry group of the harmonic oscillator. The Hamiltonian equations of motion on each orbit form a Lax system X = (X,F), where X and F are elements of the symplectic Lie algebra. The elements of the matrix X are the generators of the symplectic Lie algebra, viz., the one-body collective quadratic functions of the positions and momenta of the galactic masses. The matrix F is composed from the self-gravitating potential energy, the angular velocity, and the hydostatic pressure. Solutions to the hamiltonian dynamical system on Sp(3,R)/U(3) are given by symplectic isospectral deformations. The Casimirs of Sp(3,R), equal to the traces of powers of X, are conserved quantities.
Symmetry of crystals and molecules
Ladd, Mark
2014-01-01
This book successfully combines a thorough treatment of molecular and crystalline symmetry with a simple and informal writing style. By means of familiar examples the author helps to provide the reader with those conceptual tools necessary for the development of a clear understanding of what are often regarded as 'difficult' topics. Christopher Hammond, University of Leeds This book should tell you everything you need to know about crystal and molecular symmetry. Ladd adopts an integrated approach so that the relationships between crystal symmetry, molecular symmetry and features of chemical interest are maintained and reinforced. The theoretical aspects of bonding and symmetry are also well represented, as are symmetry-dependent physical properties and the applications of group theory. The comprehensive coverage will make this book a valuable resource for a broad range of readers.
SYMMETRY IN WORLD TRADE NETWORK
Institute of Scientific and Technical Information of China (English)
Hui WANG; Guangle YAN; Yanghua XIAO
2009-01-01
Symmetry of the world trade network provides a novel perspective to understand the world-wide trading system. However, symmetry in the world trade network (WTN) has been rarely studied so far. In this paper, the authors systematically explore the symmetry in WTN. The authors construct WTN in 2005 and explore the size and structure of its automorphism group, through which the authors find that WTN is symmetric, particularly, locally symmetric to a certain degree. Furthermore, the authors work out the symmetric motifs of WTN and investigate the structure and function of the symmetric motifs, coming to the conclusion that local symmetry will have great effect on the stability of the WTN and that continuous symmetry-breakings will generate complexity and diversity of the trade network. Finally, utilizing the local symmetry of the network, the authors work out the quotient of WTN, which is the structural skeleton dominating stability and evolution of WTN.
Wilczek, Frank
2004-01-01
Powerful symmetry principles have guided physicists in their quest for nature's fundamental laws. The successful gauge theory of electroweak interactions postulates a more extensive symmetry for its equations than are manifest in the world (8 pages) Powerful symmetry principles have guided physicists in their quest for nature's fundamental laws. The successful gauge theory of electroweak interactions postulates a more extensive symmetry for its equations than are manifest in the world. The discrepancy is ascribed to a pervasive symmetry-breaking field, which fills all space uniformly, rendering the Universe a sort of exotic superconductor. So far, the evidence for these bold ideas is indirect. But soon the theory will undergo a critical test depending on whether the quanta of this symmetry-breaking field, the so-called Higgs particles, are produced at the Large Hadron Collider (due to begin operation in 2007).
Release of peppermint flavour compounds from chewing gum: effect of oral functions
DEFF Research Database (Denmark)
Haahr, Anne-Mette; Bardow, A.; Thomsen, C.E.;
2004-01-01
During chewing, the oral cavity functions like a bellow, forcing volatile flavour compounds into the exhaling air to the nasal compartment. Accordingly, we hypothesised that flavour release from chewing gum is predominantly governed by chewing frequency (CF), although other oral functions, like...... masseter muscle activity (MMA), chewing force (CFO), and saliva flow rate (SFR), may also play a role. In 10 healthy young males, the retronasal expired air of menthol and menthone from peppermint-flavoured (2%) chewing gum was determined as functions of CF, SFR, MMA, and CFO. The experimental setup...
An MCMC Study of General Squark Flavour Mixing in the MSSM
Energy Technology Data Exchange (ETDEWEB)
Herrmann, Björn [Annecy, LAPTH; De Causmaecker, Karen [Intl. Solvay Inst., Brussels; Fuks, Benjamin [UPMC, Paris (main); Mahmoudi, Farvah [Lyon, Ecole Normale Superieure; O' Leary, Ben [Wurzburg U.; Porod, Werner [Wurzburg U.; Sekmen, Sezen [Kyungpook Natl. U.; Strobbe, Nadja [Fermilab
2015-10-05
We present an extensive study of non-minimally flavour violating (NMFV) terms in the Lagrangian of the Minimal Supersymmetric Standard Model (MSSM). We impose a variety of theoretical and experimental constraints and perform a detailed scan of the parameter space by means of a Markov Chain Monte-Carlo (MCMC) setup. This represents the first study of several non-zero flavour-violating elements within the MSSM. We present the results of the MCMC scan with a special focus on the flavour-violating parameters. Based on these results, we define benchmark scenarios for future studies of NMFV effects at the LHC.
Flavour equilibration studies of quark-gluon plasma with non-zero baryon density
Indian Academy of Sciences (India)
Abhijit Sen
2009-12-01
Flavour equilibration for a thermally equilibrated but chemically non-equilibrated quark-gluon plasma is presented. Flavour equilibration is studied enforcing baryon number conservation. In addition to the usual processes like single additional gluon production $gg \\rightleftharpoons ggg$ and its reverse and quark–antiquark pair production by gluon pair fusion $gg \\rightleftharpoons q_{i}q_{i}^{-}$ and reverse thereof, processes like quark-flavour interchanging $q_{i}q_{i}^{-} \\rightleftharpoons q_{j}q_{j}^{-}$ is also considered. The degree of equilibration is studied comparatively for various reactions/constraints that are being considered.
Measurements of heavy-flavour decay leptons with ALICE
Directory of Open Access Journals (Sweden)
Sakai Shingo
2015-01-01
Full Text Available We present measurements of electrons and muons from heavy-flavour hadron decays at central and forward rapidity performed by the ALICE Collaboration in p–Pb (√sNN = 5.02 TeV and Pb–Pb collisions (√sNN = 2.76 TeV. Electrons are reconstructed using several detectors of the ALICE central barrel. Muons are reconstructed using the muon spectrometer at forward rapidity (2.5 < y < 4. The nuclear modification factors in Pb–Pb (RAA and in p–Pb (RpPb collisions, and the azimuthal anisotropy (v2 in Pb– Pb collisions will be discussed. Theoretical predictions are compared with the data. In addition, the measurement of the azimuthal correlation between electrons from heavyflavour hadron decays and charged hadrons in p–Pb collisions will be shown.
Two-Baryon Correlation Functions in 2-flavour QCD
Francis, Anthony; Rae, Thomas D; Wittig, Hartmut
2013-01-01
We present first results for two-baryon correlation functions, computed using $N_f=2$ flavours of O($a$) improved Wilson quarks, with the aim of explaining potential dibaryon bound states, specifically the H-dibaryon. In particular, we use a GEVP to isolate the groundstate using two-baryon (hyperon-hyperon) correlation functions $\\big(\\langle C_{XY}(t)C_{XY}(0) \\rangle$, where $XY=\\Lambda\\Lambda, \\Sigma\\Sigma, N\\Xi, \\cdots\\big)$, each of which has an overlap with the H-dibaryon. We employ a `blocking' algorithm to handle the large number of contractions, which may easily be extended to N-baryon correlation functions. We also comment on its application to the analysis of single baryon masses ($n$, $\\Lambda$, $\\Xi$, $\\cdots$). This study is performed on an isotropic lattice with $m_\\pi = 460$ MeV, $m_\\pi L = 4.7$ and $a = 0.063$ fm.
Heat and storage effects on the flavour of peanuts.
el-Kayati, S M; Fadel, H H; Abdel Mageed, M; Farghal, S A
1998-12-01
Two peanut varieties, Giza 4 and Giza 5 were subjected to different heat treatments such as drying in solar drier at air speed 0.5 and 2 m/sec with average temperature 45 and 60 degrees C and heating in oven at 120 and 150 degrees C. The sensory evaluation of the two varieties showed insignificant differences among varieties and heating processes. A correlation between the sensory and instrumental data was found. The high sensory scores of samples heated at 150 degrees C were attributed to the presence of high concentration of pyrazines which were thought to contribute to flavour and aroma of fresh roasted peanut. A comparative study between the main chemical classes retained in peanut samples after storage for 3 months at room temperature showed that the aldehydes derived lipids increased significantly in the solar dried samples. The antioxidative components produced via Maillard reaction resulted in oxidative stability of the samples heated in oven.
Flavour physics and the Large Hadron Collider beauty experiment.
Gibson, Valerie
2012-02-28
An exciting new era in flavour physics has just begun with the start of the Large Hadron Collider (LHC). The LHCb (where b stands for beauty) experiment, designed specifically to search for new phenomena in quantum loop processes and to provide a deeper understanding of matter-antimatter asymmetries at the most fundamental level, is producing many new and exciting results. It gives me great pleasure to describe a selected few of the results here-in particular, the search for rare B(0)(s)-->μ+ μ- decays and the measurement of the B(0)(s) charge-conjugation parity-violating phase, both of which offer high potential for the discovery of new physics at and beyond the LHC energy frontier in the very near future. PMID:22253243
Flavour physics and the Large Hadron Collider beauty experiment.
Gibson, Valerie
2012-02-28
An exciting new era in flavour physics has just begun with the start of the Large Hadron Collider (LHC). The LHCb (where b stands for beauty) experiment, designed specifically to search for new phenomena in quantum loop processes and to provide a deeper understanding of matter-antimatter asymmetries at the most fundamental level, is producing many new and exciting results. It gives me great pleasure to describe a selected few of the results here-in particular, the search for rare B(0)(s)-->μ+ μ- decays and the measurement of the B(0)(s) charge-conjugation parity-violating phase, both of which offer high potential for the discovery of new physics at and beyond the LHC energy frontier in the very near future.
Exact Dynamical and Partial Symmetries
Leviatan, A
2010-01-01
We discuss a hierarchy of broken symmetries with special emphasis on partial dynamical symmetries (PDS). The latter correspond to a situation in which a non-invariant Hamiltonian accommodates a subset of solvable eigenstates with good symmetry, while other eigenstates are mixed. We present an algorithm for constructing Hamiltonians with this property and demonstrate the relevance of the PDS notion to nuclear spectroscopy, to quantum phase transitions and to mixed systems with coexisting regularity and chaos.
Flavour oscillations and CP asymmetry in semileptonic Bs0 decays
Energy Technology Data Exchange (ETDEWEB)
Beale, Steven Thomas; /York U., Canada
2010-01-01
The B{sub s}{sup 0} meson spontaneously transforms into its antiparticle ({bar B}{sub s}{sup 0}). These 'flavour oscillations' occur periodically with a frequency that may be measured. The oscillation frequency is related to the fundamental parameters of the electroweak interaction. Measuring the frequency provides a constraint on the electroweak quark coupling parameter V{sub ts} and improves the constraint on V{sub td}. Furthermore, the amplitude of the oscillation process may be slightly different in B{sub s}{sup 0} and {bar B}{sub s}{sup 0} mesons due to CP violating nature of the weak interaction. This 'asymmetry' is expected to be small (a{sub fs}{sup SM,s} = (2.06 {+-} 0.57) {center_dot} 10{sup -5}), but may be enhanced (a{sub fs}{sup s} {approx_equal} {Omicron}(1%)) by new sources of CP violation. This thesis describes a search for B{sub s}{sup 0} flavour oscillations and charge asymmetry in the B{sub s}{sup 0} {yields} D{sub s}{sup -}{mu}{sup +}{nu}{sub {mu}}X (D{sub s}{sup -} {yields} K*{sup 0}K{sup -}) decay mode using 5.0 fb{sup -1} of D0 data. A lower limit is placed on the oscillation frequency, {Delta}m{sub s} > 9.9 ps{sup -1} with an expected sensitivity to oscillations below 14.8 ps{sup -1}. The charge asymmetry is measured to be a{sub fs}{sup s} = 0.018 {+-} 0.025(stat) {+-} 0.002(syst). A combination of these measurements with other decay modes is also presented.
Karp, Dagan; Riggins, Paul; Whitcher, Ursula
2011-01-01
We exhaustively analyze the toric symmetries of CP^3 and its toric blowups. Our motivation is to study toric symmetry as a computational technique in Gromov-Witten theory and Donaldson-Thomas theory. We identify all nontrivial toric symmetries. The induced nontrivial isomorphisms lift and provide new symmetries at the level of Gromov-Witten Theory and Donaldson-Thomas Theory. The polytopes of the toric varieties in question include the permutohedron, the cyclohedron, the associahedron, and in fact all graph associahedra, among others.
The conservation of orbital symmetry
Woodward, R B
2013-01-01
The Conservation of Orbital Symmetry examines the principle of conservation of orbital symmetry and its use. The central content of the principle was that reactions occur readily when there is congruence between orbital symmetry characteristics of reactants and products, and only with difficulty when that congruence does not obtain-or to put it more succinctly, orbital symmetry is conserved in concerted reaction. This principle is expected to endure, whatever the language in which it may be couched, or whatever greater precision may be developed in its application and extension. The book ope
Symmetries of Quantum Nonsymmetric Gravity
Mebarki, N; Boudine, A; Benslama, A
1999-01-01
Symmetries of Quantum Nonsymmetric gravity are studied and the corresponding generators are constructed . The related equal time canonical (and non canonical) (anti) commutation relations are established.
Physical Theories with Average Symmetry
Alamino, Roberto C
2013-01-01
This Letter probes the existence of physical laws invariant only in average when subjected to some transformation. The concept of a symmetry transformation is broadened to include corruption by random noise and average symmetry is introduced by considering functions which are invariant only in average under these transformations. It is then shown that actions with average symmetry obey a modified version of Noether's Theorem with dissipative currents. The relation of this with possible violations of physical symmetries, as for instance Lorentz invariance in some quantum gravity theories, is briefly commented.
Quarks, baryons and chiral symmetry
Hosaka, Atsushi
2001-01-01
This book describes baryon models constructed from quarks, mesons and chiral symmetry. The role of chiral symmetry and of quark model structure with SU(6) spin-flavor symmetry are discussed in detail, starting from a pedagogic introduction. Emphasis is placed on symmetry aspects of the theories. As an application, the chiral bag model is studied for nucleon structure, where important methods of theoretical physics, mostly related to the semiclassical approach for a system of strong interactions, are demonstrated. The text is more practical than formal; tools and ideas are explained in detail w
Greiner, Walter
1989-01-01
"Quantum Dynamics" is a major survey of quantum theory based on Walter Greiner's long-running and highly successful courses at the University of Frankfurt. The key to understanding in quantum theory is to reinforce lecture attendance and textual study by working through plenty of representative and detailed examples. Firm belief in this principle led Greiner to develop his unique course and to transform it into a remarkable and comprehensive text. The text features a large number of examples and exercises involving many of the most advanced topics in quantum theory. These examples give practical and precise demonstrations of how to use the often subtle mathematics behind quantum theory. The text is divided into five volumes: Quantum Mechanics I - An Introduction, Quantum Mechanics II - Symmetries, Relativistic Quantum Mechanics, Quantum Electrodynamics, Gauge Theory of Weak Interactions. These five volumes take the reader from the fundamental postulates of quantum mechanics up to the latest research in partic...
Bosonization and Mirror Symmetry
Kachru, Shamit; Torroba, Gonzalo; Wang, Huajia
2016-01-01
We study bosonization in 2+1 dimensions using mirror symmetry, a duality that relates pairs of supersymmetric theories. Upon breaking supersymmetry in a controlled way, we dynamically obtain the bosonization duality that equates the theory of a free Dirac fermion to QED3 with a single scalar boson. This duality may be used to demonstrate the bosonization duality relating an $O(2)$-symmetric Wilson-Fisher fixed point to QED3 with a single Dirac fermion, Peskin-Dasgupta-Halperin duality, and the recently conjectured duality relating the theory of a free Dirac fermion to fermionic QED3 with a single flavor. Chern-Simons and BF couplings for both dynamical and background gauge fields play a central role in our approach. In the course of our study, we describe a chiral mirror pair that may be viewed as the minimal supersymmetric generalization of the two bosonization dualities.