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
Combining Pati-Salam and flavour symmetries
Feldmann, Thorsten; Hartmann, Florian; Kilian, Wolfgang; Luhn, Christoph
2015-10-01
We construct an extension of the Standard Model (SM) which is based on grand unification with Pati-Salam symmetry. The setup is supplemented with the idea of spontaneous flavour symmetry breaking which is mediated through flavon fields with renormalizable couplings to new heavy fermions. While we argue that the new gauge bosons in this approach can be sufficiently heavy to be irrelevant at low energies, the fermionic partners of the SM quarks, in particular those for the third generation, can be relatively light and provide new sources of flavour violation. The size of the effects is constrained by the observed values of the SM Yukawa matrices, but in a way that is different from the standard minimal-flavour violation approach. We determine characteristic deviations from the SM that could eventually be observed in future precision measurements.
Combining Pati-Salam and Flavour Symmetries
Feldmann, Thorsten; Kilian, Wolfgang; Luhn, Christoph
2015-01-01
We construct an extension of the Standard Model (SM) which is based on grand unification with Pati-Salam symmetry. The setup is supplemented with the idea of spontaneous flavour symmetry breaking which is mediated through flavon fields with renormalizable couplings to new heavy fermions. While we argue that the new gauge bosons in this approach can be sufficiently heavy to be irrelevant at low energies, the fermionic partners of the SM quarks, in particular those for the third generation, can be relatively light and provide new sources of flavour violation. The size of the effects is constrained by the observed values of the SM Yukawa matrices, but in a way that is different from the standard minimal-flavour violation approach. We determine characteristic deviations from the SM that could eventually be observed in future precision measurements.
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^{+/-}.
Discrete Symmetries and Models of Flavour Mixing
King, Stephen F.
2015-07-01
In this talk we shall give an overview of the role of discrete symmetries, including both CP and family symmetry, in constructing unified models of quark and lepton (including especially neutrino) masses and mixing. Various different approaches to model building will be described, denoted as direct, semi-direct and indirect, and the pros and cons of each approach discussed. Particular examples based on Δ(6n2) will be discussed and an A to Z of Flavour with Pati-Salam will be presented.
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 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.
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.
Chromomagnetism, flavour symmetry breaking and S-wave tetraquarks
Energy Technology Data Exchange (ETDEWEB)
Buccella, F. [Napoli Federico II Univ. (Italy). Dipartimento di Scienze Fisiche; INFN, Napoli (Italy); Hoegaasen, H. [University of Oslo, Department of Physics (Norway); Richard, J.M. [Universite Joseph Fourier-IN2P3-CNRS 53, Laboratoire de Physique Subatomique et Cosmologie, Grenoble (France); Sorba, P. [Laboratoire d' Annecy-le-Vieux de Physique Theorique (LAPTH) (France)
2007-02-15
The chromomagnetic interaction, with full account for flavour-symmetry breaking, is applied to S-wave configurations containing two quarks and two antiquarks. Phenomenological implications are discussed for light, charmed, charmed and strange, hidden-charm and double-charm mesons, and extended to their analogues with beauty. (orig.)
Chromomagnetism, flavour symmetry breaking and S-wave tetraquarks
International Nuclear Information System (INIS)
The chromomagnetic interaction, with full account for flavour-symmetry breaking, is applied to S-wave configurations containing two quarks and two antiquarks. Phenomenological implications are discussed for light, charmed, charmed and strange, hidden-charm and double-charm mesons, and extended to their analogues with beauty. (orig.)
Chromomagnetism, flavour symmetry breaking and S-wave tetraquarks
Buccella, F.; Høgaasen, H.; Richard, J.-M.; Sorba, P.
2007-02-01
The chromomagnetic interaction, with full account for flavour-symmetry breaking, is applied to S-wave configurations containing two quarks and two antiquarks. Phenomenological implications are discussed for light, charmed, charmed and strange, hidden-charm and double-charm mesons, and extended to their analogues with beauty.
Chromomagnetism, flavour symmetry breaking and S-wave tetraquarks
Buccella, F; Richard, J M; Sorba, Paul; Buccella, Franco; Hogaasen, Hallstein; Richard, Jean-Marc; Sorba, Paul
2007-01-01
The chromomagnetic interaction, with full account for flavour-symmetry breaking, is applied to S-wave configurations containing two quarks and two antiquarks. Phenomenological implications are discussed for light, charmed, charmed and strange, hidden-charm and double-charm mesons, and extended to their analogues with beauty.
Chromomagnetism, flavour symmetry breaking and S-wave tetraquarks
Buccella, Franco; Hogaasen, Hallstein; Richard, Jean-Marc; Sorba, Paul
2006-01-01
The chromomagnetic interaction, with full account for flavour-symmetry breaking, is applied to S-wave configurations containing two quarks and two antiquarks. Phenomenological implications are discussed for light, charmed, charmed and strange, hidden-charm and double-charm mesons, and extended to their analogues with beauty.
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.
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
Minimal gauge-Higgs unification with a flavour symmetry
Energy Technology Data Exchange (ETDEWEB)
Martinelli, Guido [Dip. di Fisica, Univ. di Roma ' La Sapienza' , and INFN, Sez. di Roma, Piazzale Aldo Moro 2, 00185 Rome (Italy); Salvatori, Matteo [Dep. de Fisica Teorica, C-XI, and Ist. de Fisica Teorica, C-XVI, Univ. Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Scrucca, Claudio Alessandro [Institut de Physique, Univ. de Neuchatel, Rue Breguet 1, 2000 Neuchatel (Switzerland); Silvestrini, Luca [Dip. di Fisica, Univ. di Roma ' La Sapienza' , and INFN, Sez. di Roma, Piazzale Aldo Moro 2, 00185 Rome (Italy); Physik-Department T31, TU-Muenchen, 85748 Garching (Germany)
2005-10-15
We show that a flavour symmetry a la Froggatt-Nielsen can be naturally incorporated in models with gauge-Higgs unification, by exploiting the heavy fermions that are anyhow needed to realize realistic Yukawa couplings. The case of the minimal five-dimensional model, in which the SU(2){sub L} x U(1){sub Y} electroweak group is enlarged to an SU(3){sub W} group, and then broken to U(1){sub em} by the combination of an orbifold projection and a Scherk-Schwarz twist, is studied in detail. We show that the minimal way of incorporating a U(1){sub F} flavour symmetry is to enlarge it to an SU(2){sub F} group, which is then completely broken by the same orbifold projection and Scherk-Schwarz twist. The general features of this construction, where ordinary fermions live on the branes defined by the orbifold fixed-points and messenger fermions live in the bulk, are compared to those of ordinary four-dimensional flavour models, and some explicit examples are constructed.
Flavour symmetries in a renormalizable SO(10) model
Ferreira, P. M.; Grimus, W.; Jurčiukonis, D.; Lavoura, L.
2016-05-01
In the context of a renormalizable supersymmetric SO (10) Grand Unified Theory, we consider the fermion mass matrices generated by the Yukawa couplings to a 10 ⊕ 120 ⊕ 126 ‾ representation of scalars. We perform a complete investigation of the possibilities of imposing flavour symmetries in this scenario; the purpose is to reduce the number of Yukawa coupling constants in order to identify potentially predictive models. We have found that there are only 14 inequivalent cases of Yukawa coupling matrices, out of which 13 cases are generated by Zn symmetries, with suitable n, and one case is generated by a Z2 ×Z2 symmetry. A numerical analysis of the 14 cases reveals that only two of them-dubbed A and B in the present paper-allow good fits to the experimentally known fermion masses and mixings.
Flavour symmetries in a renormalizable SO(10) model
Ferreira, P M; Jurčiukonis, D; Lavoura, L
2015-01-01
In the context of a renormalizable supersymmetric SO(10) Grand Unified Theory, we consider the fermion mass matrices generated by the Yukawa couplings to a $\\mathbf{10} \\oplus \\mathbf{120} \\oplus \\overline{\\mathbf{126}}$ representation of scalars. We perform a complete investigation of the possibilities of imposing flavour symmetries in this scenario; the purpose is to reduce the number of Yukawa coupling constants in order to identify potentially predictive models. We have found that there are only 14 inequivalent cases of Yukawa coupling matrices, out of which 13 cases are generated by $Z_n$ symmetries, with suitable $n$, and one case is generated by a $Z_2 \\times Z_2$ symmetry. A numerical analysis of the 14 cases reveals that only two of them---dubbed A and B in the present paper---allow good fits to the experimentally known fermion masses and mixings.
SU(3) flavour symmetry breaking and charmed states
International Nuclear Information System (INIS)
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.
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 CKM matrix from a scheme of flavour symmetry breaking
International Nuclear Information System (INIS)
A theoretical |VCKMth| mixing matrix which is a function of the four mass ratios and the CP violating phase α is derived from a simple scheme for breaking the flavour permutational symmetry. We assumed that the symmetry breaking pattern is the same in the u and d-sectors, and imposed a phenomenologically motivated constraint on the amount of mixing of singlet and doublet irreducible representations of S(3)L x S(3)R. A χ2 fit of the matrix of the absolute values |VCKMth| to the experimentally determined |VCKMexp| gives the best value for α=76.7 deg. and the value Jth=-2.18x10-5 for the Jarlskog invariant in good agreement with the experimental values. The agreement between |VCKMth| and |VCKMexp| is also very good with χ2=0.28
Flavour symmetry breaking in the kaon parton distribution amplitude
Directory of Open Access Journals (Sweden)
Chao Shi
2014-11-01
Full Text Available We compute the kaon's valence-quark (twist-two parton distribution amplitude (PDA by projecting its Poincaré-covariant Bethe–Salpeter wave-function onto the light-front. At a scale ζ=2 GeV, the PDA is a broad, concave and asymmetric function, whose peak is shifted 12–16% away from its position in QCD's conformal limit. These features are a clear expression of SU(3-flavour-symmetry breaking. They show that the heavier quark in the kaon carries more of the bound-state's momentum than the lighter quark and also that emergent phenomena in QCD modulate the magnitude of flavour-symmetry breaking: it is markedly smaller than one might expect based on the difference between light-quark current masses. Our results add to a body of evidence which indicates that at any energy scale accessible with existing or foreseeable facilities, a reliable guide to the interpretation of experiment requires the use of such nonperturbatively broadened PDAs in leading-order, leading-twist formulae for hard exclusive processes instead of the asymptotic PDA associated with QCD's conformal limit. We illustrate this via the ratio of kaon and pion electromagnetic form factors: using our nonperturbative PDAs in the appropriate formulae, FK/Fπ=1.23 at spacelike-Q2=17 GeV2, which compares satisfactorily with the value of 0.92(5 inferred in e+e− annihilation at s=17 GeV2.
Flavour symmetry breaking in the kaon parton distribution amplitude
Energy Technology Data Exchange (ETDEWEB)
Shi, Chao [Key Laboratory of Modern Acoustics, MOE, Institute of Acoustics, Nanjing University, Nanjing 210093 (China); Department of Physics, Nanjing University, Nanjing 210093 (China); Chang, Lei [CSSM, School of Chemistry and Physics University of Adelaide, Adelaide, SA 5005 (Australia); Roberts, Craig D. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Schmidt, Sebastian M. [Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, D-52425 Jülich (Germany); Tandy, Peter C. [Center for Nuclear Research, Department of Physics, Kent State University, Kent, OH 44242 (United States); Zong, Hong-shi [Department of Physics, Nanjing University, Nanjing 210093 (China); State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, CAS, Beijing 100190 (China); Joint Center for Particle, Nuclear Physics and Cosmology, Nanjing 210093 (China)
2014-11-10
We compute the kaon's valence-quark (twist-two parton) distribution amplitude (PDA) by projecting its Poincaré-covariant Bethe–Salpeter wave-function onto the light-front. At a scale ζ=2 GeV, the PDA is a broad, concave and asymmetric function, whose peak is shifted 12–16% away from its position in QCD's conformal limit. These features are a clear expression of SU(3)-flavour-symmetry breaking. They show that the heavier quark in the kaon carries more of the bound-state's momentum than the lighter quark and also that emergent phenomena in QCD modulate the magnitude of flavour-symmetry breaking: it is markedly smaller than one might expect based on the difference between light-quark current masses. Our results add to a body of evidence which indicates that at any energy scale accessible with existing or foreseeable facilities, a reliable guide to the interpretation of experiment requires the use of such nonperturbatively broadened PDAs in leading-order, leading-twist formulae for hard exclusive processes instead of the asymptotic PDA associated with QCD's conformal limit. We illustrate this via the ratio of kaon and pion electromagnetic form factors: using our nonperturbative PDAs in the appropriate formulae, F{sub K}/F{sub π}=1.23 at spacelike-Q{sup 2}=17 GeV{sup 2}, which compares satisfactorily with the value of 0.92(5) inferred in e{sup +}e{sup −} annihilation at s=17 GeV{sup 2}.
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
International Nuclear Information System (INIS)
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.
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
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
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 ...
Maximal conserved flavour symmetry in models with complementarity
International Nuclear Information System (INIS)
Models with complementarity for massless composite fermions are investigated. Through a study of 't Hooft's equations, we find a simple general criterion for the maximal conserved flavour group in terms of a given set of bi-fermion condensates in the Higgs picture. (orig.)
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.)
$A_4$ 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...
International Nuclear Information System (INIS)
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.)
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.)
Lepton mixing predictions including Majorana phases from Δ(6n2) flavour symmetry and generalised CP
International Nuclear Information System (INIS)
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
Minimal violation of flavour and custodial symmetries in a vectophobic Two-Higgs-Doublet-Model
International Nuclear Information System (INIS)
Tree-level accidental symmetries are known to play a fundamental role in the phenomenology of the Standard Model (SM) for electroweak interactions. So far, no significant deviations from the theory have been observed in precision, flavour and collider physics. Consequently, these global symmetries are expected to remain quite efficient in any attempt beyond the SM. Yet, they do not forbid rather unorthodox phenomena within the reach of current LHC experiments. This is illustrated with a vectophobic Two-Higgs-Doublet-Model (2HDM) where effects of a light, flavour-violating and custodian (pseudo)scalar might be observed in the Bs→μ+μ- decay rate and in the diphoton invariant mass spectrum at around 125 GeV.
International Nuclear Information System (INIS)
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 Δ(6n2) series. The most well-known member is Δ(24)=S4. I present results of several extensive studies of lepton mixing predictions obtained in models with a Δ(6n2) flavour group that preserve either the full Klein symmetry or a Z2 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. Furthermore, I present results for neutrinoless double-beta decay.
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
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)
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.
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.)
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.
The breaking of the flavour permutational symmetry Mass textures and the CKM matrix
Mondragón, A
1999-01-01
Different anzätse for the breaking of the flavour permutational symmetry acording to S_{L}(3) X S_{R}(3) \\supset S_{L}(2) X S_{R}(2) give different Hermitian mass matrices of the same modified Fritzsch type, which differ in the symmetry breaking pattern. In this work we obtain a clear and precise indication on the preferred symmetry breaking scheme from a fit of the predicted |V^{th}| to the experimentally determined absolute values of the elements of the CKM matrix. The preferred scheme leads to simple mass textures and allows us to compute the CKM mixing matrix, the Jarlskog invariant J, and the three inner angles of the unitarity triangle in terms of four quark mass ratios and only one free parameter: the CP violating phase \\Phi. Excellent agreement with the experimentally determined absolute values of the entries in the CKM matrix is obtained for \\Phi=90 degrees. The corresponding computed values of the Jarlskog invariant and the inner angles are J=3 x 10^{-5}, agreement with current data on CP violation...
Fermion mass hierarchies and flavour mixing from a minimal discrete symmetry
Feruglio, Ferruccio; Lin, Yin
2008-09-01
We construct a simple model of fermion masses based on a spontaneously broken S×Z flavour group. At the leading order, in the neutrino sector S is broken down to a ν-ν parity subgroup that enforces a maximal atmospheric mixing angle and a vanishing θ. In the charged lepton sector the ν-ν parity is maximally broken and the resulting mass matrix is nearly diagonal. The charged lepton mass hierarchy is automatically reproduced by the S symmetry breaking parameter alone. A careful analysis shows that, after the inclusion of all relevant subleading effects, the model predicts θ=π/4+O(λc2) and θ=O(λc2), λ denoting the Cabibbo angle. A simple extension to the quark sector is also illustrated, where the mass spectrum and the mixing angles are naturally reproduced, with the exception of the mixing angle between the first two generations, that requires a small accidental enhancement.
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
CP Violating Phase and Quark Mixing Angles from Flavour Permutational Symmetry-Breaking
Mondragón, A
2000-01-01
The phase equivalence of the theoretical quark mixing matrix ${\\bf V}^{th}$ derived from the breaking of the flavour permutational symmetry and the phenomenological parametrizations ${\\bf V}^{PDG}$ and ${\\bf V}^{KM}$ is explicitly exhibited. From here, we derive exact explicit expressions for the three mixing angles and the CP violating phase of the two phenomenological parametrizations in terms of the quark mass ratios $(m_{u}/m_{t}, m_{c}/m_{t}, m_{d}/m_{b}, m_{s}/m_{b})$ and the parameters $Z^{*1/2}$ and $\\Phi^*$ characterizing the preferred symmetry breaking pattern. The computed values for the CP violating phase and the mixing angles of the standard parametrization advocated by the Particle Data Group are $\\delta^*_{13}=73.2^\\circ$, $\\sin\\theta^*_{12}=0.222$, $\\sin\\theta^*_{13}=0.0036$, and $\\sin\\theta^*_{23}=0.040$. The computed values of the CP-violating phase and the mixing angles of the Kobayashi-Maskawa parametrization are $\\delta^*_{KM}=96.4^\\circ$, $\\sin\\theta^*_{1}=0.2225$, $\\sin\\theta^*_{2}=0.03...
The breaking of the flavour permutational symmetry Mass textures and the CKM matrix
Mondragón, A
1998-01-01
Different ansaetze for the breaking of the flavour permutational symmetry according to S(3)L X S(3)R in S(2)L X S(2)R give different Hermitian mass matrices of the same modified Fritzsch type which are classified in terms of an auxiliary S(2) which is not a subgroup of S(3)L X S(3)R. A fit of the predicted theoretical Vckm to the experimentally determined absolute values of the elements of the CKM matrix gives a clear and precise indication on the preferred symmetry breaking scheme. The preferred scheme leads to simple mass textures and allows us to compute the CKM mixing matrix in terms of four quark mass ratios and only one free parameter: the CP violating phase Phi. Excellent agreement with the experimentally determined absolute values of the entries in the CKM matrix is obtained for Phi = 76.8 deg. The corresponding computed value of the Jarlskog invariant is J = -2.18 10^-5 in very good agreement with current data on CP violation in the neutral kaon-antikaon system.
Phenomenological Tests of Supersymmetric $A_4$ Family Symmetry Model of Neutrino Mass
Hirsch, M; Skadhauge, S; Valle, José W F; Del Moral, A V; 10.1103/PhysRevD.69.093006
2004-01-01
Recently Babu, Ma and Valle proposed a model of quark and lepton mixing based on $A_4$ symmetry. Within this model the lepton and slepton mixings are intimately related. We perform a numerical study in order to derive the slepton masses and mixings in agreement with present data from neutrino physics. We show that, starting from three-fold degeneracy of the neutrino masses at a high energy scale, a viable low energy neutrino mass matrix can indeed be obtained in agreement with constraints on lepton flavour violating $\\mu$ and $\\tau$ decays. The resulting slepton spectrum must necessarily include at least one mass below 200 GeV which can be produced at the LHC. The predictions for the absolute Majorana neutrino mass scale $m_0 \\geq 0.3$ eV ensure that the model will be tested by future cosmological tests and $\\beta\\beta_{0\
CP and Lepton-Number Violation in GUT Neutrino Models with Abelian Flavour Symmetries
Ellis, John; Gomez, Mario E.; Lola, Smaragda
2006-01-01
We study the possible magnitudes of CP and lepton-number-violating quantities in specific GUT models of massive neutrinos with different Abelian flavour groups, taking into account experimental constraints and requiring successful leptogenesis. We discuss SU(5) and flipped SU(5) models that are consistent with the present data on neutrino mixing and upper limits on the violations of charged-lepton flavours and explore their predictions for the CP-violating oscillation and Majorana phases. In ...
The $750\\,\\text{GeV}$ diphoton resonance in the light of a 2HDM with $S_3$ flavour symmetry
Hernández, A E Cárcamo; Schumacher, E
2016-01-01
Very recently we proposed a predictive 2 Higgs Doublet Model with $S_{3}$ flavour symmetry that successfully accounts for fermion masses and mixings. In this letter, motivated by the $750$ GeV Higgs diphoton resonance recently reported by the ATLAS and CMS collaborations, we modify this model by adding exotic top partners with electric charge $\\frac{5}{3}$. This simple modification enables our model to successfully account for the Higgs diphoton excess at $750\\,\\text{GeV}$ provided that the exotic quark masses are in the range $[1,1.8]$ TeV, for $O(1)$ exotic quark Yukawa couplings.
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...
The discrete family symmetry as a possible solution to the flavour problem
Dziewit, Bartosz; Richter, Monika; Zając, Sebastian; Zrałek, Marek
2016-01-01
In order to explain the fermions masses and mixing parameters appearing in the lepton sector of the Standard Model, one proposes the extension of its symmetry. A discrete, non-abelian subgroup of $U(3)$ is added to the gauge group $SU(3)_{C}\\times SU(2)_{L}\\times U(1)_{Y}$ . Apart from that, one assumes the existence of one extra Higgs doublet. This article focuses mainly on the mathematical theorems and computational techniques which brought us to the results.
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...
Generalized permutation symmetry and the flavour problem in SU(2)sub(L)xU(1)
International Nuclear Information System (INIS)
A generalized permutation group is introduced as a possible horizontal symmetry for SU(2)sub(L)xU(1) gauge theories. It leads to the unique two generation quark mass matrices with a correct prediction for the Cabibbo angle. For three generations the model exhibits spontaneous CP violation, correlates the Kobayashi-Maskawa mixing parameters s1 and s3 and predicts an upper bound for the running top quark mass of approximately 45 GeV. The hierarchy of generations is due to a hierarchy of vacuum expectation values rather than of Yukawa coupling constants. (orig.)
Mass Matrix Model Broken From A4 To 2 $\\leftrightarrow$ 3 Symmetry
Fukuyama, Takeshi
2008-01-01
2$\\leftrightarrow$3 symmetry is realized by the breaking from alterating group of degree 4 ($A4$) symmetry. $A4$ explains why the generation number is three. However the mass matrices are realized in the form of the breaking to $2\\leftrightarrow 3$ symmetry $\\times Z_3$, which leads us to $2\\leftrightarrow 3$ symmetric mass matrix with vanishing (1,1) component. Thus the $3\\times 3$ mass matrix model with $2\\leftrightarrow 3$ symmetry and vanishing (1,1) component has the group theoretical background as the symmetry in GUT model.
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.
Flavour reformulation and flavour stability
Yang, Ni
2012-01-01
ABSTRACT This project addressed two areas in the flavour industry – flavour reformulation required as a consequence of ingredient changes and flavour stability in solid food products. The aim of the flavour reformulation study was to evaluate both instrumental and modelling approaches to reformulate commercial flavourings for food products of different fat contents. A strawberry flavouring was chosen, which delivered an acceptable flavour in pectin jelly (0% fat) but did not perform so...
Mondragón, A
2000-01-01
We show that the theoretical mixing matrix V^{th} derived from the breaking of the flavour permutational symmetry and the standard parametrization V^{PDG} advocated by the Particle Data Group are equivalent, up to a redefinition of the unobservable phases of the quark fields in the mass representation. From here, we derive exact explicit expressions for the three mixing angles in terms of the quark mass ratios (m_{u}/m_{t}, m_{c}/m_{t}, m_{d}/m_{b}, m_{s}/m_{b}) and the parameters Z^{*1/2} and \\Phi* characterizing the preferred symmetry breaking pattern. The predicted values for the CP violating phase and the mixing angles are: \\delta*_{13}=72 degrees, \\sin(\\theta*_{12})=0.220817, almost exactly with the central values of the experimentally determined quantities.
Non-zero $\\theta_{13}$ and leptonic CP phase with $A_4$ Symmetry
M., Sruthilaya
2016-01-01
We consider a model based on $A_4$ symmetry to explain lepton mixing. The spontaneous symmetry breaking of $A_4$ symmetry leads to a co-bimaximal mixing matrix. We add a $Z_2\\times Z_2$ invariant perturbation in the charged lepton sector to make the predicted mixing angles compatible with the recent results from neutrino oscillation experiments. We find that the mixing angles obtained in this approach come well within the $3\\sigma$ ranges of their experimental values. We also study the implications of this model on the other phenomenological observables, such as CP violating phase, Jarlskog invariant and the effective Majorana mass $|M_{ee}|$.
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).
$A_4$ 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.
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.
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.
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...
Neutrino and Changed Lepton Flavour Today
Alonso, R; Hernandez, D; Merlo, L; Rigolin, S
2013-01-01
Flavour physics is a priceless window on physics beyond the Standard Model. In particular, flavour violation in the lepton sector looks very promising, as high precision measurements are prospected in future experiments investigating on $\\mu\\rightarrow e$ conversion in atomic nuclei: the predictions for this observable are analysed in the context of the type I Seesaw mechanism. Furthermore, new ideas to explain the Flavour Puzzle recently appeared, mainly based on a possible dynamical origin of the Yukawa couplings and on flavour symmetries. The focus of this proceeding will be set on the Minimal Flavour Violation ansatz and on the role of the neutrino Majorana character: when an $O(2)_{N}$ flavour symmetry acts on the right-handed neutrino sector, the minimum of the scalar potential allows for large mixing angles -in contrast to the simplest quark case- and predicts a maximal Majorana phase. This leads to a strong correlation between neutrino mass hierarchy and mixing pattern.
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
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.
Compatibility of theta13 and the Type I Seesaw Model with A4 Symmetry
Chen, Mu-Chun; O'Bryan, Jon-Michael; Wijangco, Alexander M; Yu, Felix
2012-01-01
We derive formulae for neutrino masses and mixing angles in a type I seesaw framework with an underlying A4 flavor symmetry. In particular, the Majorana neutrino mass matrix includes contributions from an A4 triplet, 1, 1', and 1" flavon fields. Using these formulae, we constrain the general A4 parameter space using the updated global fits on neutrino mixing angles and mass squared differences, including results from the Daya Bay and RENO experiments, and we find predictive relations among the mixing parameters for certain choices of the triplet vacuum expectation value. In the normal hierarchy case, sizable deviation from maximal atmospheric mixing is predicted, and such deviation is strongly correlated with the value of theta13 in the range of ~ (8-10) degrees. On the other hand, such deviation is negligible and insensitive to theta13 in the inverted mass hierarchy case. We also show expectations for the Dirac CP phase resulting from the parameter scan. Future refined measurements of neutrino mixing angles ...
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.
Buras, Andrzej J
1992-01-01
This volume is a collection of review articles on the most outstanding topics in heavy flavour physics. All the authors have made significant contributions to this field. The book reviews in detail the theoretical structure of heavy flavour physics within the Standard Model and its confrontation with existing experimental data. The physics of the top quark and of the Higgs play an important role in this volume. Beginning with radiative electroweak corrections and their impressive tests at LEP and hadron colliders, the book summarizes the present status of quark mixing, CP violation and rare de
Buras, Andrzej J
1998-01-01
This volume is a collection of review articles on the most outstanding topics in heavy flavour physics. All the authors have made significant contributions to this field. The book reviews in detail the theoretical structure of heavy flavour physics and confronts the Standard Model and some of its extensions with existing experimental data.This new edition covers new trends and ideas and includes the latest experimental information. Compared to the previous edition interesting new activities are included and some of the key contributions are updated. Particular attention is paid to the discover
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.
Buras, Andrzej J
2011-01-01
This decade will allow to improve the resolution of the short distance scales by at least an order of magnitude, extending the picture of fundamental physics down to scales $5\\cdot 10^{-20}$m with the help of the LHC. Further resolution down to scales as short as $10^{-21}$m should be possible with the help of high precision experiments in which flavour violating processes will play a prominent role. Will this increase in resolution allow us to see new particles (new animalcula) similarly to what Antoni van Leeuvenhoek saw by discovering bacteria in 1676? The basic question for particle physics is how these new animalcula will look like and which difficulties of the Standard Model (SM) they will help us to solve and which new puzzles and problems they will bring with them. I will describe what role flavour physics will play in these exciting times provided this new world is animalculated.
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.
Ab initio Calculations of Charge Symmetry Breaking in the A =4 Hypernuclei
Gazda, Daniel; Gal, Avraham
2016-03-01
We report on ab initio no-core shell model calculations of the mirror Λ hypernuclei H4Λ and He4Λ , using the Bonn-Jülich leading-order chiral effective field theory hyperon-nucleon potentials plus a charge symmetry breaking Λ -Σ0 mixing vertex. In addition to reproducing rather well the 0g.s . + and 1exc+ binding energies, these four-body calculations demonstrate for the first time that the observed charge symmetry breaking splitting of mirror levels, reaching hundreds of keV for 0g.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 H4Λ(0g.s . +) binding energy at the Mainz Microtron [A. Esser et al. (A1 Collaboration), Phys. Rev. Lett. 114, 232501 (2015)] and the He4Λ(1exc+) excitation energy [T.O. Yamamoto et al. (J-PARC E13 Collaboration), Phys. Rev. Lett. 115, 222501 (2015)].
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)].
A to Z of Flavour with Pati-Salam
King, Stephen F.
2014-08-01
We propose an elegant theory of flavour based on A 4 × Z 5 family symmetry with Pati-Salam unification which provides an excellent description of quark and lepton masses, mixing and CP violation. The A 4 symmetry unifies the left-handed families and its vacuum alignment determines the columns of Yukawa matrices. The Z 5 symmetry distinguishes the right-handed families and its breaking controls CP violation in both the quark and lepton sectors. The Pati-Salam symmetry relates the quark and lepton Yukawa matrices, with Y u = Y ν and Y d ~ Y e . Using the see-saw mechanism with very hierarchical right-handed neutrinos and CSD4 vacuum alignment, the model predicts the entire PMNS mixing matrix and gives a Cabibbo angle θ C ≈ 1/4. In particular, for a discrete choice of Z 5 phases, it predicts maximal atmospheric mixing, θ {23/ l } = 45° ± 0.5° and leptonic CP violating phase δ l = 260° ± 5°. The reactor angle prediction is θ {13/ l } = 9° ± 0.5°, while the solar angle is 34° ≳ θ {12/ l } ≳ 31°, for a lightest neutrino mass in the range 0 ≲ m 1 ≲ 0.5 meV, corresponding to a normal neutrino mass hierarchy and a very small rate for neutrinoless double beta decay.
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.
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\
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.
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...
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...
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.
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
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...
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
International Nuclear Information System (INIS)
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
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.
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.
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.
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...
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.
KLOE results in flavour physics and prospects for KLOE-2
International Nuclear Information System (INIS)
A review of the most recent results in flavour physics obtained by the KLOE experiment at DAΦNE collider together with prospects for kaon physics at KLOE-2 is presented. A brief description of KS meson lifetime measurement and determination of upper limit for BR(Ks→3π0) are discussed. In addition a CPT symmetry test in the Standard Model Extension framework and study of the Dalitz plot of η→π+π−π0 are reported. Last two sections are devoted to the KLOE-2 project and prospects in flavour physics
KLOE results in flavour physics and prospects for KLOE-2
Energy Technology Data Exchange (ETDEWEB)
Czerwiński, E., E-mail: eryk.czerwinski@uj.edu.pl [Institute of Physics, Jagiellonian University, Cracow (Poland); Babusci, D.; Badoni, D.; Balwierz, I.; Bencivenni, G.; Bini, C.; Bloise, C.; Bocci, V.; Bossi, F.; Branchini, P.; Budano, A.; Caldeira Balkeståhl, L.; Capon, G.; Ceradini, F.; Ciambrone, P.; Czerwiński, E.; Dané, E.; De Lucia, E.; De Robertis, G.; De Santis, A.; and others
2013-08-15
A review of the most recent results in flavour physics obtained by the KLOE experiment at DAΦNE collider together with prospects for kaon physics at KLOE-2 is presented. A brief description of K{sub S} meson lifetime measurement and determination of upper limit for BR(K{sub s}→3π{sup 0}) are discussed. In addition a CPT symmetry test in the Standard Model Extension framework and study of the Dalitz plot of η→π{sup +}π{sup −}π{sup 0} are reported. Last two sections are devoted to the KLOE-2 project and prospects in flavour physics.
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.
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.)
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 ...
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.
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.
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.
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 ...
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.
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).
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...
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...
Critical Number of Flavours in QED
Bashir, A; Gutiérrez-Guerrero, L X; Tejeda-Yeomans, M E
2011-01-01
We demonstrate that in unquenched quantum electrodynamics (QED), chiral symmetry breaking ceases to exist above a critical number of fermion flavours $N_f$. This is a necessary and sufficient consequence of the fact that there exists a critical value of electromagnetic coupling $\\alpha$ beyond which dynamical mass generation gets triggered. We employ a multiplicatively renormalizable photon propagator involving leading logarithms to all orders in $\\alpha$ to illustrate this. We study the flavour and coupling dependence of the dynamically generated mass analytically as well as numerically. We also derive the scaling laws for the dynamical mass as a function of $\\alpha$ and $N_f$. Up to a multiplicative constant, these scaling laws are related through $(\\alpha, \\alpha_c) \\leftrightarrow (1/N_f, 1/N_f^c)$. Calculation of the mass anomalous dimension $\\gamma_m$ shows that it is always greater than its value in the quenched case. We also evaluate the $\\beta$-function. The criticality plane is drawn in the $(\\alpha...
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.
Heavy Flavour Production at HERA
International Nuclear Information System (INIS)
ZEUS and H1 results on heavy quark production using the HERA data from 1995 to 2000 are summarised with emphasis on unresolved problems. The HERA upgrade and its impact on future heavy flavour measurements is briefly discussed
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.
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.
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 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...
Flavour Physics of Leptons and Dipole Moments.
Raidal, M.; van der Schaaf, A.; Bigi, I.; Mangano, M.L.; Semertzidis, Y.; Abel, S.; Albino, S.; Antusch, S.; Arganda, E.; Bajc, B.; Banerjee, S.; Biggio, C.; Blanke, M.; W. Bonivento; Branco, G. C.
2008-01-01
This chapter of the report of the ``Flavour in the era of the LHC'' Workshop discusses the theoretical, phenomenological and experimental issues related to flavour phenomena in the charged lepton sector and in flavour-conserving CP-violating processes. We review the current experimental limits and the main theoretical models for the flavour structure of fundamental particles. We analyze the phenomenological consequences of the available data, setting constraints on explicit models beyond the ...
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
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.
Higgs and flavour as doors to new physics
Sala, Filippo
2016-04-01
A natural solution to the hierarchy problem of the Fermi scale motivates signals of New Physics at current and near-future experiments. After a critical synthesis of this general motivation, we concentrate our attention on the interplay between LHC searches for new resonances, and precision measurements of both Higgs couplings and flavour violating observables. We do so for i) the Higgs sectors of the NMSSM and MSSM, as paradigmatic examples of theories providing extra scalars, and for ii) CKM-like flavour symmetries, with a focus on U(2)3. This article is mainly based on several papers by the author, but it also reviews other recent related results. Its goal is to provide a synthetic, yet comprehensive, orientation on these subjects, at the dawn of several (ATLAS and CMS, LHCb, NA62, etc.) forthcoming experimental results.
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.
Natural suppression of flavour-changing neutral currents in supersymmetric gauge theories
International Nuclear Information System (INIS)
Induced flavour-changing neutral currents (FCNC) in supersymmetric unified theories are investigated both in models with the standard SU(2)sub(L) x U(1) gauge symmetry and in models with an extra U tilde(1) gauge symmetry. Supersymmetric extension of the natural flavour conservation laws for neutral currents is obtained by adding a condition regarding the assumed type of supersymmetry breaking. This condition ensures no direct flavour-changing couplings of neutral gauge-Higgs fermions and at the same time is necessary and sufficient for the natural suppression of the induced FCNC. It is found that in the class of models satisfying the new condition the contribution of the scalar partners of quarks to the induced strangeness-changing neutral current is comparable to that of the quarks in K sub(L) → μantiμ, while it is negligibly small in K sub(L)-K sub(S) mass difference. (author)
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.
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.
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.)
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.
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.
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 alignment in physics beyond the standard model
International Nuclear Information System (INIS)
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 extension of the Standard
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...
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\
The STAR Heavy Flavour Tracker
International Nuclear Information System (INIS)
In order to understand the partonic EOS of matter created at RHIC, one needs to study both the collectivity of the produced matter and the degree of thermalization. We propose to address this physics through the study of heavy flavour hadrons in high-energy nuclear collisions at RHIC. The heavy flavour tracker (HFT), a tracking upgrade of the STAR experiment, is being designed to provide an unambiguous measurement of charm hadrons through the direct reconstruction of hadronic decays. These measurements require high accuracy space points near the collision vertex. The current design of our detector uses a novel CMOS-based sensor, allowing for a low-mass and high-resolution detector element. We provide rate estimations for D0 v2 measurements in Au+Au collisions at 200 GeV
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.)
Linking Natural Supersymmetry to Flavour Physics
Dudas, Emilian; Pokorski, Stefan; Ziegler, Robert
2013-01-01
With the aim of linking natural supersymmetry to flavour physics, a model is proposed based on a family symmetry G \\times U(1), where G is a discrete nonabelian subgroup of SU(2), with both F-term and (abelian) D-term supersymmetry breaking. A good fit to the fermion masses and mixing is obtained with the same U(1) charges for the left- and right- handed quarks of the first two families and the right-handed bottom quark, and with zero charge for the left-handed top-bottom doublet and the the right handed top. The model shows an interesting indirect correlation between the correct prediction for the V_{ub}/V_{cb} ratio and large right-handed rotations in the (s,b) sector, required to diagonalise the Yukawa matrix. For the squarks, one obtains almost degenerate first two generations. The main source of the FCNC and CP violation effects is the splitting between the first two families and the right-handed sbottom determined by the relative size of F-term and D-term supersymmetry breaking. The presence of the larg...
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 ...
Linking natural supersymmetry to flavour physics
International Nuclear Information System (INIS)
With the aim of linking natural supersymmetry to flavour physics, a model is proposed based on a family symmetry G×U(1), where G is a discrete nonabelian subgroup of SU(2), with both F-term and (abelian) D-term supersymmetry breaking. A good fit to the fermion masses and mixing is obtained with the same U(1) charges for the left- and right- handed quarks of the first two families and the right-handed bottom quark, and with zero charge for the left-handed top-bottom doublet and the the right handed top. The model shows an interesting indirect correlation between the correct prediction for the Vub/Vcb ratio and large right-handed rotations in the (s,b) sector, required to diagonalise the Yukawa matrix. For the squarks, one obtains almost degenerate first two generations. The main source of the FCNC and CP violation effects is the splitting between the first two families and the right-handed sbottom determined by the relative size of F-term and D-term supersymmetry breaking. The presence of the large right-handed rotation implies that the bounds on the masses of the first two families of squarks and the right handed sbottom are in a few to a few tens TeV range. The picture that emerges is light stops and left handed sbottom and much heavier other squarks
Flavour perception: aroma, taste and texture interactions
Tournier, Carole; Sulmont-Rossé, Claire; Guichard, Elisabeth
2007-01-01
Flavour perception is determinant for the acceptability of food products by consumers. Aroma and taste play an important role in flavour perception and it is well known that the chemical composition of the matrix and consequently its structure influences release and perception of flavour. However, from simultaneous measurements of human perception and physical concentration in vivo, texture – aroma and texture – taste interactions are not always explained by physico-chemical mechanisms. Moreo...
Flavour Chemistry of Chicken Meat: A Review
Jayasena, Dinesh D.; Ahn, Dong Uk; Nam, Ki Chang; Jo, Cheorun
2013-01-01
Flavour comprises mainly of taste and aroma and is involved in consumers’ meat-buying behavior and preferences. Chicken meat flavour is supposed to be affected by a number of ante- and post-mortem factors, including breed, diet, post-mortem ageing, method of cooking, etc. Additionally, chicken meat is more susceptible to quality deterioration mainly due to lipid oxidation with resulting off-flavours. Therefore, the intent of this paper is to highlight the mechanisms and chemical compounds res...
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.
Definitions of minimal flavour violation for leptons
International Nuclear Information System (INIS)
Neutrino masses imply the violation of lepton flavour and new physics beyond the Standard Model. However, flavour change has only been observed in oscillations. In analogy with the quark sector, we could deduce the existence of a principle of Minimal Flavour Violation also for Leptons (MFVL). Such an extension is not straightforward, since the mechanisms generating neutrino masses are unknown and many scenarios can be envisaged. Thus, we explore some possible definitions of MFVL and propose a notion that can include many models. We show, furthermore, that flavour violating processes are not necessarily controlled by the PMNS mixing matrix. (author)
Flavour and Higgs physics near the Fermi scale
Sala, Filippo
2013-01-01
After a discussion of the hierarchy problem of the Fermi scale, we study the flavour and Higgs boson(s) phenomenology of new physics close to it, both in general and in the specific cases of Supersymmetry and composite Higgs models. First, we promote the approximate U(2)^3 symmetry exhibited by the quark sector of the Standard Model to be a more fundamental symmetry of Nature, and explore its phenomenological consequences from an effective field theory point of view. We also study the embedding of natural Supersymmetry within the U(2)^3 framework, focusing in particular on the pattern of flavour and CP violation in B decays. Then we consider the CP-even scalar sector of the next-to-minimal supersymmetric Standard Model. We quantify the impact of current and foreseen measurements of the Higgs boson signal strengths on the physical parameters, deriving analytical relations for this purpose, and we outline a possible overall strategy to search for the other Higgs scalars. Finally we analyze the constraints from ...
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^+\
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.
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.
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.
Charged Lepton Flavour Violation in Supersymmetric Low-Scale Seesaw Models
Ilakovac, Amon; Popov, Luka
2013-01-01
We study charged lepton flavour violation in low-scale seesaw models of minimal supergravity, which realize large neutrino Yukawa couplings thanks to approximate lepton-number symmetries. There are two dominant sources of lepton flavour violation in such models. The first source originates from the usual soft supersymmetry-breaking sector, whilst the second one is entirely supersymmetric and comes from the supersymmetric neutrino Yukawa sector. Within the framework of minimal supergravity, we consider both sources of lepton flavour violation, soft and supersymmetric, and calculate a number of possible lepton-flavour-violating transitions, such as the photonic decays of muons and taus, mu -> e gamma, tau -> e gamma and tau -> mu gamma, their neutrinoless three-body decays, mu -> e e e, tau -> e e e, tau -> mu mu mu, tau -> e e mu and tau -> e mu mu, and the coherent mu -> e conversion in nuclei. After taking into account the exclusion bounds placed by present experiments of lepton flavour violation, we derive ...
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
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.
Flavour physics and CP-violation
International Nuclear Information System (INIS)
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 evidence for CP-violation and its important role in our understanding of flavour dynamics. (author)
Recent studies on the biogeneration of flavours
Energy Technology Data Exchange (ETDEWEB)
Fuganti, Claudio; Zucchi, Gioia [CNR, Milan (Italy). Dipt. di Chimica del Politecnico
1997-07-01
The requirements by the flavour industry for large quantities of natural flavouring compounds, has stimulated the research for enzymatic procedures enabling the access from extractive precursor to rare odorants not accessible by extraction, including alcohols, aldehyde, lactones and sulfurated compounds. The ability of the SNIF-NMR technique in the authentication of the products is discussed.
Flavour Physics and Implication for New Phenomena
Isidori, Gino
2015-01-01
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.
Selected topics in heavy flavour physics
International Nuclear Information System (INIS)
We review the status of flavour physics in spring 2014. The numerous accurate new measurements of flavour experiments have enabled us to test our theoretical understanding of flavour processes with an unprecedented precision. At first sight the dominant amount of measurements seems to be standard model like. Having a closer look one finds, however, that in most of the observables there is still some considerable space for new effects. In addition many discrepancies are still not yet settled. For further investigations and definite conclusions an improvement of the theoretical precision as well as the experimental one is mandatory. Communicated by Professor Alan Martin (topical review)
Novel structured emulsions for delivering of food flavours
Mao, Like
2014-01-01
Flavour release from food is determined by the binding of flavours to other food ingredients and the partition of flavour molecules among different phases. Food emulsions are used as delivery systems for food flavours, and tailored structuring in emulsions provides novel means to better control flavour release. The current study investigated four structured oil-in-water emulsions with structuring in the oil phase, oil-water interface, and water phase. Oil phase structuring was achieved by the...
Flavour models with Dirac and fake gluinos
International Nuclear Information System (INIS)
In the context of supersymmetric models where the gauginos may have both Majorana and Dirac masses we investigate the general constraints from flavour-changing processes on the scalar mass matrices. One finds that the chirality-flip suppression of flavour-changing effects usually invoked in the pure Dirac case holds in the mass insertion approximation but not in the general case, and fails in particular for inverted hierarchy models. We quantify the constraints in several flavour models which correlate fermion and scalar superpartner masses. We also discuss the limit of very large Majorana gaugino masses compared to the chiral adjoint and Dirac masses, where the remaining light eigenstate is the “fake” gaugino, including the consequences of suppressed couplings to quarks beyond flavour constraints
Strong color fields and heavy flavour production
International Nuclear Information System (INIS)
The clustering of color sources provides a natural framework of partonic interactions producing strong color fields. We study the consequences of these color fields in the production of heavy flavour and in the behavior of the nuclear modified factor.
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.
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.
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.
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...
Spontaneous CP symmetry violation in electroweak theories
International Nuclear Information System (INIS)
The phenomenon of CP symmetry violation is reviewed with reference to the neutral kaon systems and its realization as manifest, or a spontaneous breaking in the context of electroweak gauge theories is discussed. It is shown that, as in the standard electroweak model, spontaneous CP violation can be achieved in the left-right symmetric and partially ununified models through extension of the Higgs sector and inclusion of an appropriate discrete symmetry. The experimental constraints on flavour changing neutral current in these models are also discussed. (author). 25 refs., 2 figs
Thermodynamics of lattice QCD with 3 flavours of colour-sextet quarks
Kogut, J B
2011-01-01
We have been studying QCD with 2 flavours of colour-sextet quarks to distinguish whether it is QCD-like or conformal. For comparison we are now studying QCD with 3 flavours of colour-sextet quarks, which is believed to be conformal in the chiral limit. Here we present the results of simulations of lattice QCD with 3 colour-sextet quarks at finite temperatures on lattices of temporal extent $N_t=4$ and 6, with masses small enough to yield access to the chiral limit. As for the 2-flavour case, we find well-separated deconfinement and chiral-symmetry restoration transitions, both of which move to appreciably weaker couplings as $N_t$ is increased from 4 to 6. If this theory is conformal, we would expect there to be a bulk chiral transition at a fixed coupling. For this reason we conclude that for $N_t=4$ and 6, the chiral and hence the deconfinement transitions are in the strong-coupling domain where the theory is essentially quenched. The similarity between the behaviours of the 2 and 3 flavour theories suggest...
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)
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...
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.)
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...... comprised three separate series of a 4-min chewing period. These series differed only with respect to CF, i.e., habitual frequency, and 60 and 88 strokes/min. Results showed that more than 50% of the released menthol and menthone could be retrieved in the expired air and saliva. After 2-min of chewing, the...
The supersymmetric flavour problem in 5D GUTs and its consequences for LHC phenomenology
International Nuclear Information System (INIS)
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.)
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.
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...
Minimal flavour violation and SU(5)-unification
Energy Technology Data Exchange (ETDEWEB)
Barbieri, Riccardo; Senia, Fabrizio [Scuola Normale Superiore, Pisa (Italy); INFN, Pisa (Italy)
2015-12-15
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. (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.)
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.
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.
Generalised geometrical CP violation in a T′ lepton flavour model
International Nuclear Information System (INIS)
We analyse the interplay of generalised CP transformations and the non-Abelian discrete group T′ and use the semi-direct product Gf=T′⋊HCP, 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 δ in the lepton mixing matrix is predicted to be δ≅π/2 or 3π/2. Thus, the CP violating effects in neutrino oscillations are predicted to be maximal (given the values of the neutrino mixing angles) and experimentally observable. We present also predictions for the sum of the neutrino masses, for the Majorana CPV phases and for the effective Majorana mass in neutrinoless double beta decay. The predictions of the model can be tested in a variety of ongoing and future planned neutrino experiments
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.
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.
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.
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
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
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.
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.
A flavour physics scenario for the 750 GeV diphoton anomaly
Bonilla, Cesar; Srivastava, Rahul; Valle, Jose W F
2016-01-01
A simple variant of a realistic flavour symmetry scheme for fermion masses and mixings provides a possible interpretation of the diphoton anomaly as an electroweak singlet "flavon". The existence of TeV scale vector-like T-quarks required to provide adequate values for CKM parameters can also naturally account for the diphoton anomaly. Correlations between $V_{ub}$ and $V_{cb}$ with the vector-like T-quark mass can be predicted. Should the diphoton anomaly survive in a future Run, our proposed interpretation can also be tested in upcoming B and LHC studies.
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.
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.
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 $F_2^{c\\bar{c}}$.
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
Heavy flavour physics from top to bottom
Energy Technology Data Exchange (ETDEWEB)
Paulini, M. [Lawrence Berkeley National Lab., CA (United States); CDF and D0 Collaborations
1997-01-01
We review the status of heavy flavour physics at the Fermilab Tevatron collider by summarizing recent top quark and B physics results from CDF and D0. In particular we discuss the measurement of the top quark mass and top production cross section as well as B meson lifetimes and time dependent B{bar B} mixing results. An outlook of perspectives for top and B physics in Run II starting in 1999 is also given. 38 refs., 23 figs., 8 tabs.
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.
Creating innovative flavour and texture experiences
Edwards-Stuart, Rachel
2009-01-01
The work presented in this thesis describes the use of scientific research in the development of novel texture and flavour experiences and their potential for use in fine gastronomy. In order to create an interesting textural experience, modified celluloses were investigated. Their unique property is that they have the ability to gel at high temperatures, but return to the solution state upon cooling. This phenomena was used to test the hypothesis that hot gels made from these materials could...
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
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...
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…
International Nuclear Information System (INIS)
We present many varied chiral symmetry models at the quark level which consistently describe strong interaction hadron dynamics. The pattern that emerges is a nonstrange current quark mass scale mcur ≅ (34-69) MeV and a current quark mass ratio (ms/m)cur ≅ 5-6 along with no strange quark content in nucleons. (orig./WL)
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.
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.
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.
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.
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
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
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
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
Hurth, Tobias
2006-01-01
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 --> pi pi and B --> 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.
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.
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.)
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.
Exclusive search for supersymmetry with same-flavour di-lepton final states with the ATLAS detector
International Nuclear Information System (INIS)
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-1 of √(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 Ss ≥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 Ss≥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 Λ=40 TeV exceeding the current LEP limits.
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...
On the Physics Case of a Super Flavour Factory
Browder, T; Gershon, T; Hazumi, M; Hurth, Tobias; Okada, Y; Stocchi, A
2008-01-01
We summarize the physics case of a high-luminosity e+e- flavour factory collecting an integrated luminosity of 50-75 ab^(-1). Many New Physics sensitive measurements involving B and D mesons and tau leptons, unique to a Super Flavour Factory, can be performed with excellent sensitivity to new particles with masses up to ~100 (or even ~1000 TeV). Flavour- and CP-violating couplings of new particles that may be discovered at the LHC can be measured in most scenarios, even in unfavourable cases assuming minimal flavour violation. Together with the LHC, a Super Flavour Factory, following either the SuperKEKB or the SuperB proposal, could be soon starting the project of reconstructing the New Physics Lagrangian.
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.
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
International Nuclear Information System (INIS)
We show that, even if a priori mixings of positive-parity but flavour-violating eigenstates are allowed in physical hadrons, in the strong flavour symmetry limit the mixing angle will drop out of the matrix elements of the Yukawa and electromagnetic Hamiltonians that lead to non-leptonic and weak radiative decays of hyperons in this scheme. We compare this result with related theorems for the same W-mediated decays and give a concrete example of this behaviour by considering the U-spin symmetry of baryons and the U-doublet formed by p andΣ+. (author)
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...
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
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.
Flavour physics, supersymmetry and grand unification
Nierste, Ulrich
2011-01-01
A global fit to quark flavour-physics data disfavours the Standard Model with 3.6 standard deviations and points towards new CP-violating physics in meson-antimeson mixing amplitudes. Tevatron data call for a new Bs-Bs-bar mixing phase and new physics in Bd-Bd-bar mixing alleviates the tension on the unitarity triangle driven by B(B-> tau nu). In supersymmetric GUT models the large atmospheric neutrino mixing angle can influence b -> s transitions. I present the results of a recent analysis in an SO(10) GUT model which accomodates the large Bs-Bs-bar mixing phase while simultaneously obeying all other experimental constraints.
On the Isomorphic Description of Chiral Symmetry Breaking by Non-Unitary Lie Groups
Bietenholz, Wolfgang
2009-01-01
It is well-known that chiral symmetry breaking ($\\chi$SB) in QCD with $N_{f}=2$ light quark flavours can be described by orthogonal groups as $O(4) \\to O(3)$, due to local isomorphisms. Here we discuss the question how specific this property is. We consider generalised forms of $\\chi$SB involving an arbitrary number of light flavours of continuum or lattice fermions, in various representations. We search systematically for isomorphic descriptions by non-unitary, compact Lie groups. It turns o...
The energy levels of the heavy flavour baryons in the topological soliton model
International Nuclear Information System (INIS)
The energy levels of the charm and bottom as well as the mixed flavour hyperons are calculated with the model in which the hyperons are described as bound states of a topological SU(2) soliton and K-, D- and B-mesons. The spectra are obtained in a modified version of the Skyrme model where the chiral symmetry breaking term in the Lagrangian density is modified so as to incorporate the different values of the decay constants of the mesons of different flavour. The predicted strange and charmed hyperon spectra are in very good agreement with the empirical values, while the bottom hyperon energies that are more sensitive to the short range dynamics are somewhat below the empirical values. The predicted hyperfine spectra are remarkably close to those obtained with the constituent quark model, more or less independently of the short-distance properties of the effective Lagrangian. We suggest that this feature reflects the presence of an induced nonabelian gauge potential generated by the interplay between 'fast' and 'slow' degrees of freedom in the meson-soliton system. (orig.)
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
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.
Two-point functions for flavour changing currents in QCD
International Nuclear Information System (INIS)
We complete the calculations of two-point functions in QCD by presenting the results for the flavour changing vector current, including perturbative and non-perturbative contributions (to first ordern in αsub(s)). (orig.)
Open heavy flavour production: conceptual framework and implementation issues
International Nuclear Information System (INIS)
Heavy flavour production is an important quantum chromodynamics (QCD) process both in its own right and as a key component of precision global QCD analysis. Apparent disagreements between fixed-flavour scheme calculations of b-production rate with experimental measurements in hadro-, lepto- and photo-production provide new impetus for a thorough examination of the theory and phenomenology of this process. We review existing methods of calculation and place them in the context of the general perturbative QCD framework of Collins. A distinction is drawn between scheme dependence and implementation issues related to quark mass effects near threshold. We point out a so far overlooked kinematic constraint on the threshold behaviour, which greatly simplifies the variable flavour number scheme. This obviates the need for the elaborate existing prescriptions and leads to robust predictions. It can facilitate the study of current issues on heavy flavour production as well as precision global QCD analysis. (author)
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...... EU. In application of this Regulation, a Register of about 2800 flavouring substances used in or on foodstuffs in the EU Member States was adopted and are currently being evaluated according to the evaluation programme laid down by Commission Regulation. The EU Safety Evaluation Procedure is derived...... not to present a safety concern, have been specified. In the project a very comprehensive database (the FLAVIS database) has been developed for the evaluation. It compiles information on the about 2800 flavouring substances used in Europe: specifications, structural class, food categories used in...
Risk assessment of flavouring substances used in foods
DEFF Research Database (Denmark)
Norby, Karin; Beltoft, Vibe Meister; Greve, Krestine; Reffstrup, Trine Klein; Gry, Jørn
2006-01-01
not to present a safety concern, have been specified. In the project a very comprehensive database (the FLAVIS database) has been developed for the evaluation. It compiles information on the about 2800 flavouring substances used in Europe: specifications, structural class, food categories used in......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...
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 ...
Relationship between texture of gels and flavour release
Koliandris, Andreas
2009-01-01
To provide further insight into the relationship between the structure of hydrocolloid solutions and gels and perception of taste and flavour, solutions of gelatin and locust bean gum, and gels prepared from mixtures of (a) high acyl and low acyl gellan (b) carrageenan and locust bean gum were studied. Both solutions contained sodium chloride and the gels were flavoured with ethyl butyrate. The gels were classified from rheological measurements into 3 categories: strong/brittle, intermedi...
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...
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...
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.
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...
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...
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.
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
Understanding Darjeeling tea flavour on a molecular basis.
Gohain, Bornali; Borchetia, Sangeeta; Bhorali, Priyadarshini; Agarwal, Niraj; Bhuyan, L P; Rahman, A; Sakata, K; Mizutani, M; Shimizu, B; Gurusubramaniam, G; Ravindranath, R; Kalita, M C; Hazarika, M; Das, Sudripta
2012-04-01
Darjeeling teas are the highest grown teas in the world and preferred for its flavour, aroma and quality. Apart from the genetic makeup of the plant, earlier reports suggest that insect infestation, particularly jassids and thrips triggers the aroma and flavour formation in Darjeeling tea. The present work encompasses the identification of the genes/transcriptomes responsible for the typical flavour of Darjeeling tea, besides understanding the role of jassids and thrips in particular, in producing the best cup character and quality. The quantitative real time PCR analysis was based on a suppression subtractive hybridisation forward library of B157 (tea clone infested with thrips), providing us transcripts related to aroma and flavour formation. We observed the expression of genes like leucine zipper, ntd, nced, geraniol synthase, raffinose synthase, trehalose synthase, amylase, farnesyl transferase, catalase, methyl transferase, linalool synthase, peroxidases, elicitor responsive proteins, linamarase, nerolidol linalool synthase 2, 12-oxophytodienoate reductase, glucosidase, MYB transcription factor, and alcohol dehydrogenase, highly regulated due to insect infestation, manufacturing stresses and mechanical injury. The first report on gene expression dynamics in thrips infested Darjeeling tea leaves can be extrapolated with increase in volatiles which is responsible for enhancing the quality of Darjeeling tea, specially the flavour and aroma of the infusion. We hope to model these responses in order to understand the molecular changes that occur during Darjeeling tea flavour formation. PMID:22328090
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...
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...
Flavored Peccei-Quinn symmetry
Ahn, Y H
2014-01-01
In an attempt to uncover any underlying physics in the standard model (SM), we suggest a $\\mu$--$\\tau$ power law in the lepton sector, such that relatively large 13 mixing angle with bi-large ones can be derived. On the basis of this, we propose a neat and economical model for both the fermion mass hierarchy problem of the SM and a solution to the strong CP problem, in a way that no domain wall problem occurs, based on $A_{4}\\times U(1)_{X}$ symmetry in a supersymmetric framework. Here we refer to the global $U(1)_X$ symmetry that can explain the above problems as "flavored Peccei-Quinn symmetry". In the model, a direct coupling of the SM gauge singlet flavon fields responsible for spontaneous symmetry breaking to ordinary quarks and leptons, both of which are charged under $U(1)_X$, comes to pass through Yukawa interactions, and all vacuum expectation values breaking the symmetries are connected each other. So, the scale of Peccei-Quinn symmetry breaking is shown to be roughly located around $10^{12}$ GeV se...
Chiral symmetry restoration and axial vector renormalization for Wilson fermions
Reisz, T
2000-01-01
Lattice gauge theories with Wilson fermions break chiral symmetry. In theU(1) axial vector current this manifests itself in the anomaly. On the otherhand it is generally expected that the axial vector flavour mixing current isnon-anomalous. We give a short, but strict proof of this to all orders ofperturbation theory, and show that chiral symmetry restauration implies aunique multiplicative renormalization constant for the current. This constantis determined entirely from an irrelevant operator in the Ward identity. Thebasic ingredients going into the proof are the lattice Ward identity, chargeconjugation symmetry and the power counting theorem. We compute therenormalization constant to one loop order. It is largely independent of theparticular lattice realization of the current.
Chiral symmetry and chiral-symmetry breaking
International Nuclear Information System (INIS)
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
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.
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), ...
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.
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.
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...
Three flavour QCD from the holographic principle
International Nuclear Information System (INIS)
Building on recent research into five-dimensional holographic models of QCD, we extend this work by including the strange quark with an SU(3)L x SU(3)R gauge symmetry in the five-dimensional theory. In addition we deform the naive AdS metric with a single parameter, thereby breaking the conformal symmetry at low energies. The vector and axial vector sectors are studied in detail and both the masses and decay constants are calculated with the additional parameters. It is shown that with a single extra degree of freedom, exceptional agreement with experimental results can be obtained in the light quark sector while the kaon sector of the vector and axial vector octet is found to give around 10% agreement with lattice results. We propose some simple extensions to this work to be taken up in future research
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.
Authenticity and Traceability of Vanilla Flavour by Analysis of Stable Isotopes
DEFF Research Database (Denmark)
Hansen, Anne-Mette Sølvbjerg; Fromberg, Arvid; Frandsen, Henrik Lauritz
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 Ga...
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.)
Measurement of charm flow with the STAR Heavy Flavour Tracker
International Nuclear Information System (INIS)
In order to understand the partonic EOS of matter created at RHIC, one needs to study both the collectivity of the produced matter and the degree of thermalization. Anisotropic flow measurements have already demonstrated the development of partonic collectivity at RHIC (Ackermann K et al 2001 Phys. Rev. Lett. 86 402), and now it is necessary to address the issue of quark thermalization. Since the masses of the heavy flavour quarks are larger than the possible excitations of the system created in the collision, their collective motion could be used to indicate the degree of thermalization of the light flavour quarks (u, d, s). The Heavy Flavour Tracker (HFT), a tracking upgrade of the STAR experiment, is being designed to provide an unambiguous measurement of charm quark flow through the direct reconstruction of the D0. The current design of our detector uses a novel CMOS-based sensor, allowing for a low mass and high resolution detector element
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.
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.
Challenges for New Physics in the Flavour Sector
International Nuclear Information System (INIS)
In these proceedings I present a personal perspective of the challenges for new physics (NP) searches in the flavour sector. Since the CKM mechanism of flavour violation has been established to a very high precision, we know that physics beyond the Standard Model can only contribute sub-dominantly. Therefore, any realistic model of physics beyond the Standard Model (SM) must respect the stringent constrains from flavour observables like b → sγ, BS → μ+μ-, ΔF=2 processes etc., in a first step. In a second step, it is interesting to ask the question if some deviations from the SM predictions (like the anomalous magnetic moment of the muon or recently observed discrepancies in tauonic B decays or B → K*μ+μ-) can be explained by a model of NP without violating bounds from other observables. (author)
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.
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.
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).
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 ...
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.
Complex quaternions in space-time symmetry and relativistic spin-flavour supermultiplets
International Nuclear Information System (INIS)
Some direct consequences of the isomorphism between Dirac algebra and SU=4 are discussed. The general framework of a curved space-time theory is presented which comprises various known models and description of elementary particles. Especially the theory shows the interesting facets related only to certain choice of the relativistic representation spaces
Spectrum and Decays of S-wave tetraquarks from chromomagnetism with flavour symmetry breaking
Buccella, Franco
2008-08-01
From a necessary condition for "open door" decays of tetraquarks into two pseudoscalar mesons or into a vector and pseudoscalar mesons, we deduce that the lighter states may have strong couplings into these final states.
Spectrum and Decays of S-wave tetraquarks from chromomagnetism with flavour symmetry breaking
International Nuclear Information System (INIS)
From a necessary condition for 'open door' decays of tetraquarks into two pseudoscalar mesons or into a vector and pseudoscalar mesons, we deduce that the lighter states may have strong couplings into these final states
Open heavy flavour at the CERN-LHC
Directory of Open Access Journals (Sweden)
Mischke André
2014-04-01
Full Text Available In this contribution recent open heavy flavour measurements from the CERN-Large Hadron Collider are presented and discussed. The focus is on prompt D meson and heavy flavour decay lepton production in pp, p-Pb and Pb-Pb collisions. Open beauty is studied through a displaced J/Ψ analysis. Heavy quarks allow to probe the degree of thermalization and energy loss mechanism(s in the hot QCD matter produced in heavy ion collisions, whereas pp provide important baseline measurements for the studies in heavy ion collisions. The p-Pb data give an access to investigate cold nuclear matter effects.
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.
New physics searches in heavy flavours in ATLAS
International Nuclear Information System (INIS)
Precision determinations of the flavour sector allow the search for indirect new physics signatures. At the forefront of these studies are the determinations of interference of new physics with known ΔF = 1 and ΔF = 2 processes. The ATLAS collaboration explores this area with competitive results measuring the CP violating phase φs from Bs0 → J/ψφ decays and investigating rare B decays with dileptons in the final state with data collected at the Large Hadron Collider. In this paper, the latest ATLAS results relevant for new physics searches in the heavy flavour sector will be discussed. (authors)
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
Spontaneous CP violation and non-abelian family symmetry in SUSY
International Nuclear Information System (INIS)
We present a model based on an SU(3) family symmetry providing a full description of quark and lepton masses and mixing angles. CP is spontaneously broken in the flavour sector reproducing the observed results of the Jarlskog invariant in the CKM mixing matrix. Our model predicts the amount of CP violation to be expected in the neutrino sector and solves the Supersymmetric CP and FCNC problems in a gravity mediation scenario. (author)
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.
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.
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.
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)
Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister; Lund, Pia; Binderup, Mona-Lise
2011-01-01
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 substances were considered to have genotoxic potential. The substances were evaluated through a stepwise approach (the Procedure) that integrates information on structure-activity relationships, intake...
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.
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
International Nuclear Information System (INIS)
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 → K*l+l- decay, whose angular decay distribution will be studied at LHC and gives access to a large number of observables and the b→sνanti ν 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.)
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
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.
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.)
Heavy flavour physics at colliders with silicon strip vertex detectors
International Nuclear Information System (INIS)
The physics of heavy flavours has played a dominant role in high energy physics research ever since the discovery of charm in 1974, followed by the τ lepton in 1975 and bottom in 1977. With the startup of the large experiments at the e+e- colliders LEP and the SLC a new type of detector system has now come into operation which has a major impact on the studies of heavy flavours: the silicon strip vertex detector. The basic design principles of these novel detector systems are outlined and three representative experimental realizations are discussed. The impact of these detectors on the studies of the properties of heavy flavours is just emerging and focuses on the measurement of lifetimes and the tagging of the presence of heavy flavour hadrons in hadronic events. The tools that are being developed for these studies are described as well as details of representative analyses. The potential of these devices and the associated technological developments that were necessary for their application in the colliding beam environment is reflected in a plethora of new proposals to build sophisticated silicon detector systems for a large variety of future high energy physics applications. Two examples will be briefly sketched, a vertex detector for an asymmetric e+e- bottom factory and a large scale tracking system for a multipurpose detector at one of the new large hadron colliders. (orig.)
Flavour Condensates in Brane Models and Dark Energy
Mavromatos, Nick E; Tarantino, Walter
2009-01-01
In the context of a microscopic model of string-inspired foam, in which foamy structures are provided by brany point-like defects (D-particles) in space-time, we discuss flavour mixing as a result of flavour non-preserving interactions of (low-energy) fermionic stringy matter excitations with the defects. Such interactions involve splitting and capture of the matter string state by the defect, and subsequent re-emission. Quantum fluctuations of the D-particles induce a non-trivial space-time background; in some circumstances this could be akin to a cosmological Friedman-Robertson Walker expanding-Universe, with weak (but non-zero) particle production. Furthermore the D-particle medium can induce an MSW type effect. We have argued previously, in the context of bosons, that the so-called flavour vacuum is the appropriate state to be used, at least for low-energy excitations, with energies/momenta up to a dynamically determined cutoff scale. In this work we evaluate the flavour-vacuum expectation value (condensa...
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
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
Family Symmetries in the era of the LHC
International Nuclear Information System (INIS)
The LHC is set to achieve a total 14 TeV collision energy for every pair of protons colliding. At this energy it will be possible to study interactions of the SM particles that may contain particles beyond it. We therefore will continue improving our understanding of particle physics, at the very least. Ideally many particles would be discovered and its interactions would be studied. A framework study for understanding the decay, mixing and CP breaking processes of these and the SM particles are the family symmetries. Proposed to explain the hierarchy of fermion masses and mixing in the SM but posed for explanations and predictions of what may happen beyond the SM. In this talk I will review the present bounds on flavour changing neutral currents and make a summary of how family symmetries can explain them.
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...
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...
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....
Symmetry Analysis of Telegraph Equation
Nadjafikhah, Mehdi; Hejazi, Seyed Reza
2010-01-01
Lie symmetry group method is applied to study the Telegraph equation. The symmetry group and its optimal system are given, and group invariant solutions associated to the symmetries are obtained. Finally the structure of the Lie algebra symmetries is determined.
Family symmetry, fermion mass matrices and cosmic texture
International Nuclear Information System (INIS)
The observed replication of fermions in three families is undoubtedly a reflection of a deeper symmetry underlying the standard model. In this paper we investigate one very elementary possibility, that physics above the grand unification scale is described by the symmetry group G x SU(3)fam with G a gauged grand unified group, and SU(3)fam a global family symmetry. The breaking of this symmetry at the GUT scale produces global texture, providing a mechanism for structure formation in the universe, and sets strong constraints on the low energy fermion mass matrix. With the addition of a 45 Higgs and certain assumptions about the relative strength of Higgs couplings, the simplest SU(5) theory yields an eight-parameter form for the fermion mass matrices, which we show is consistent with the thirteen observable masses and mixing angles. We discuss the natural suppression of flavour-changing neutral currents (FCNCs) and emphasise the rich low energy Higgs sector. With minor assumptions, the theory unifies consistently with the recent LEP data. We consider the extension to G = SO(10), where some simplification and further predictiveness emerges. Finally we discuss the dynamics of SU(3)fam texture and show that the known constraints on unification ''predict'' a GUT symmetry-breaking scale of the order required for cosmic structure formation, and by the recent detection of cosmic microwave anisotropy by COBE. (orig.)
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.)
DEFF Research Database (Denmark)
Meinert, Lene; Tikk, Kaja; Tikk, Meelis; Brockhoff, Per B.; Bredie, Wender L. P.; Bjergegaard, Charlotte; Aaslyng, Margit D.
2009-01-01
Flavour development and overall eating quality of pan-fried pork chops of longissimus dorsi from eight different raw meat qualities aged for 4 and IS days were assessed by a trained sensory panel. The raw meat qualities were obtained through combinations of strategic feeding/fasting (control vs...
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
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
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
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...
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.
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...
van der Schaft, A. J.
1987-01-01
It is argued that the existence of symmetries may simplify, as in classical mechanics, the solution of optimal control problems. A procedure for obtaining symmetries for the optimal Hamiltonian resulting from the Maximum Principle is given; this avoids the actual calculation of the optimal Hamiltonian. This procedure is based upon the notion of symmetry for the Hamiltonian system with inputs and outputs associated with an optimal control problem.
Gray, J E; Vogt, A
1997-01-01
Is symmetry informative? The answer is both yes and no. We examine what information and symmetry are and how they are related. Our approach is primarily mathematical, not because mathematics provides the final word, but because it provides an insightful and relatively precise starting point. Information theory treats transformations that messages undergo from source to destination. Symmetries are information that leave some property of interest unchanged. In this respect the studies of information and symmetry can both be regarded as a Quest for the identity transformation. PMID:9224554
DEFF Research Database (Denmark)
Beltoft, Vibe Meister; Binderup, Mona-Lise; Frandsen, Henrik Lauritz; Lund, Pia; Nørby, Karin Kristiane
data on metabolism and toxicity. The Panel concluded that for the flavouring substance, evaluated through the Procedure, no appropriate NOAEL was available and additional data are required. The present evaluation of the candidate substance L-methionylglycine [FL-no: 17.037] is only applicable for its......The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate one flavouring substance, the dipeptide L-methionylglycine [FL-no: 17.037], in the Flavouring Group Evaluation 305, using the Procedure in Commission...... use in foods that are not heated or intended to be heated. Besides the safety assessment of the flavouring substance, the specifications for the material of commerce have also been considered. Adequate specifications including complete purity criteria and identity for the material of commerce have...
New physics searches with heavy flavour with the ATLAS experiment
International Nuclear Information System (INIS)
Flavour changing neutral currents and precision measurements of CP violation are investigated by the ATLAS experiment at the Large Hadron Collider at CERN as probes to physics beyond the Standard Model. This paper presents recent update of flavour tagged time- dependent analysis of Bs → J/ψ φ, angular analysis of Bd → K*μ+μ− and a search for the rare decay B0s → μ+μ− with measurement of upper limit on its branching fraction. All analyses use 4.9 fb−1 of integrated luminosity collected in 2011 at centre-of-mass energy of 7 TeV and the results are in agreement with Standard Model predictions
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.
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
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.
$B$ 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
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 $(0.30 \\pm 0.01 \\pm 0.01) \\%$.
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
Lepton Flavour Violating top decays at the LHC
Davidson, Sacha; Perries, Stephane; Sordini, Viola
2015-01-01
We consider lepton flavour violating decays of the top quark, mediated by four-fermion operators. We compile constraints on a complete set of SU(3)*U(1)-invariant operators, arising from their loop contributions to rare decays and from HERA's single top search. The bounds on e-mu flavour change are more restrictive than l-tau; nonetheless the top could decay to a jet $+ e \\bar{\\mu}$ with a branching ratio of order $10^{-3}$. We estimate that the currently available LHC data (20 inverse-fb at 8 TeV) could be sensitive to $BR(t \\to e \\bar{\\mu}$+ jet) $ \\sim 6\\times 10^{-5}$, and extrapolate that 100 inverse-fb at 13 TeV could reach a sensitivity of $ \\sim 1 \\times 10^{-5}$.
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.
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.
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.
Lifetimes of heavy-flavour hadrons whence and whither?
Bigi, Ikaros I
1995-01-01
A theoretical treatment for the weak decays of heavy-flavour hadrons has been developed that is genuinely based on QCD. Its methodology as it applies to total lifetimes and the underlying theoretical issues are sketched. Predictions are compared with present data. One discrepancy emerges: the beauty baryon lifetime appears to be significantly shorter than expected. The ramifications of those findings are analyzed in detail.
The QCD perspective on lifetimes of heavy-flavour hadrons
Bigi, Ikaros I
1995-01-01
Over the last few years a theoretical treatment for the weak decays of heavy-flavour hadrons has been developed that is genuinely based on QCD. Its methodology is described as it applies to total lifetimes, and the underlying theoretical issues are discussed. Theoretical expectations are compared with present data. One discrepancy emerges: the beauty baryon lifetime appears to be significantly shorter than predicted. The ramifications of those findings are analyzed in detail, and future refinements are described.
A Short Guide to Flavour Physics and CP Violation
Lee, Seung J
2015-01-01
We present the invited lectures given at the second Asia-Europe-Pacific School of High-Energy Physics (AEPSHEP), which took place in Puri, India in November 2014. The series of lectures aimed at graduate students in particle experiment/theory, covering the very basics of flavor physics and CP violation, some useful theoretical methods such as OPE and effective field theories, and some selected topics of flavour physics in the era of LHC.
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.
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.
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).
The pT spectrum in heavy-flavour hadroproduction
International Nuclear Information System (INIS)
The Authors consider the transverse-momentum distribution of heavy flavours in hadronic collisions. The authors present a formalism in which large transverse-momentum logarithms are summed at the next-to-leading level, and mass effects are included exactly up to order αS3, so as to retain predictivity at both small and large transverse momenta. As an example, the Authors apply our formalism to b production at the Tevatron
The supersymmetric Higgs boson with flavoured A-terms
Energy Technology Data Exchange (ETDEWEB)
Brignole, Andrea, E-mail: brignole@pd.infn.it
2015-09-15
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.
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.
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.
Characterization of beer flavour stability (EPR - spin trapping)
International Nuclear Information System (INIS)
The beer flavour stability is coupled with free radical degradation processes. Probably, aldehydes produced during the brewery but also generated by stalling are responsible for beer flavour as well as for its breaking down. The storing beer at the lower temperatures and in the dark place inhibits, and otherwise the rising temperature and illumination accelerate the rate of such radical processes. Beers contain naturally occurring radical scavengers - antioxidants which inhibit such unwanted reactions. Then depleting of scavengers results in the breaking down of the beer stability. EPR spin trapping technique was used as monitor such processes and for characterising so the flavour stability of beer. The probe was temperated at 60 grad C in the cavity of EPR spectrometer in the presence of spin trapping agent, N-tert.-butyl-α-phenyl nitrone (PBN) and EPR spectra were recorded for few hours. After beer antioxidants become depleted, free radicals formed by the beer degradation are scavenged by PBN spin trap and this point is characterised with a dramatically increased concentration of the free radicals trapped
Kadanoff–Baym approach to flavour mixing and oscillations in resonant leptogenesis
International Nuclear Information System (INIS)
We describe a loopwise perturbative truncation scheme for quantum transport equations in the Kadanoff–Baym formalism, which does not necessitate the use of the so-called Kadanoff–Baym or quasi-particle ansaetze for dressed propagators. This truncation scheme is used to study flavour effects in the context of Resonant Leptogenesis (RL), showing explicitly that, in the weakly-resonant regime, there exist two distinct and pertinent flavour effects in the heavy-neutrino sector: (i) the resonant mixing and (ii) the oscillations between different heavy-neutrino flavours. Moreover, we illustrate that Kadanoff–Baym and quasi-particle ansaetze, whilst appropriate for the flavour-singlet dressed charged-lepton and Higgs propagators of the RL scenario, should not be applied to the dressed heavy-neutrino propagators. The use of these approximations for the latter is shown to capture only flavour oscillations, whilst discarding the separate phenomenon of flavour mixing
Self-induced conversion in dense neutrino gases: Pendulum in flavour space
Hannestad, S; Sigl, G; Wong, Y Y Y
2006-01-01
Neutrino-neutrino interactions can lead to collective flavour conversion effects in supernovae and in the early universe. We demonstrate that the case of "bipolar" oscillations, where a dense gas of neutrinos and antineutrinos in equal numbers completely converts from one flavour to another even if the mixing angle is small, is equivalent to a pendulum in flavour space. Bipolar flavour conversion corresponds to the swinging of the pendulum, which begins in an unstable upright position (the initial flavour), and passes through momentarily the vertically downward position (the other flavour) in the course of its motion. The time scale to complete one cycle of oscillation depends logarithmically on the vacuum mixing angle. Likewise, the presence of an ordinary medium can be shown analytically to contribute to a logarithmic increase in the bipolar conversion period. We further find that a more complex (and realistic) system of unequal numbers of neutrinos and antineutrinos is analogous to a spinning top subject t...
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...
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.
Symmetries of Spectral Problems
Shabat, A.
Deriving abelian KdV and NLS hierarchies, we describe non-abelian symmetries and "pre-Lax" elementary approach to Lax pairs. Discrete symmetries of spectral problems are considered in Sect. 4.2. Here we prove Darboux classical theorem and discuss a modern theory of dressing chains.
Symmetries in Lagrangian Dynamics
Ferrario, Carlo; Passerini, Arianna
2007-01-01
In the framework of Noether's theorem, a distinction between Lagrangian and dynamical symmetries is made, in order to clarify some aspects neglected by textbooks. An intuitive setting of the concept of invariance of differential equations is presented. The analysis is completed by deriving the symmetry properties in the motion of a charged…
Meshkov, Sydney
2009-01-01
The study of the symmetries of nature has fascinated scientists for eons. The application of the formal mathematical description of symmetries during the last century has produced many breakthroughs in our understanding of the substructure of matter. In this talk, a number of these advances are discussed, and the important role that George Sudarshan played in their development is emphasized
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 ...
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...
Buza, M.; Matiounine, Y.; Smith, J.; van Neerven, W. L.
1996-01-01
Starting from fixed-order perturbation theory (FOPT) we derive expressions for the heavy-flavour components of the deep-inelastic structure functions FL and F2 in the variable-flavour number scheme (VFNS). These expressions are valid in all orders of perturbation theory. This derivation establishes a relation between the parton densities parametrized at N and N light flavours. The consequences for the existing parametrizations of the parton densities are discussed. Further we show that in cha...
The formation of fat-derived flavour compounds during the ripening of Gouda-type cheese
Alewijn, M.
2006-01-01
Cheese flavour is an important quality attribute, and is mainly formed during cheese ripening. Besides compounds that are formed from protein and carbohydrates, milk fat-derived compounds are essential for cheese flavour. Before, but mainly during ripening, free fatty acids, lactones, ketones, esters, alcohols and aldehydes can be formed from milk fat, compounds that all contribute their own special character to the final cheese flavour. The formation mechanisms that lead to these compounds a...
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)
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...
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
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.)
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.
On the symmetry breaking phenomenon
Birtea, Petre; Puta, Mircea; Ratiu, Tudor S.; Tudoran, Ruazvan Micu
2006-01-01
We investigate the problem of symmetry breaking in the framework of dynamical systems with symmetry on a smooth manifold. Two cases will be analyzed: general and Hamiltonian dynamical systems. We give sufficient conditions for symmetry breaking in both cases.
Counting trees using symmetries
Bernardi, Olivier
2012-01-01
We present a new approach for counting trees, and we apply it to count multitype Cayley trees and to prove the multivariate Lagrange inversion formula. The gist of our approach is to exploit the symmetries of refined enumerative formulas: proving these symmetries is easy, and once the symmetries are proved the formulas follow effortlessly. Somewhat surprisingly, our formula for the generating function of multitype Cayley trees appears to be new, and implies certain recent results by Bousquet-M\\'elou and Chapuy. We also adapt our approach to recover known enumerative formulas for cacti counted according to their degree distribution.
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.
DEFF Research Database (Denmark)
Avery, John Scales; Rettrup, Sten; Avery, James Emil
In theoretical physics, theoretical chemistry and engineering, one often wishes to solve partial differential equations subject to a set of boundary conditions. This gives rise to eigenvalue problems of which some solutions may be very difficult to find. For example, the problem of finding...... 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...
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)
Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister; Lund, Pia; Binderup, Mona-Lise
2011-01-01
The European Food Safety Authority (EFSA) asked the Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (the Panel) 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, the Panel was requested to evaluate nine flavouring substances in the Flavouring Group Evaluation 12, Revision 2 (FGE.12Rev2), using the Procedure as referred to in the ...
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...
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.
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)
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.
Second order symmetry operators
International Nuclear Information System (INIS)
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. (paper)
IBM: discrete symmetry viewpoint
International Nuclear Information System (INIS)
It is shown that the set of information of the s and d boson operators which maintain the IBM-like form of the Hamiltonian comprises a discrete point symmetry group D2'. The transformations manifest themselves as a parameter symmetry of the IBM-1 Hamiltonian. The transformations considered are also necessary for constructing the most general IBM-2 Hamiltonian. The properties of the potential energy surfaces arising in connection with these transformations are discussed
Non-Abelian discrete gauge symmetries in 4d string models
Berasaluce-Gonzalez, M; Marchesano, F; Regalado, D; Uranga, A M
2012-01-01
We study the realization of non-Abelian discrete gauge symmetries in 4d field theory and string theory compactifications. The underlying structure generalizes the Abelian case, and follows from the interplay between gaugings of non-Abelian isometries of the scalar manifold and field identifications making axion-like fields periodic. We present several classes of string constructions realizing non-Abelian discrete gauge symmetries. In particular, compactifications with torsion homology classes, where non-Abelianity arises microscopically from the Hanany-Witten effect, or compactifications with non-Abelian discrete isometry groups, like twisted tori. We finally focus on the more interesting case of magnetized branes in toroidal compactifications and quotients thereof (and their heterotic and intersecting duals), in which the non-Abelian discrete gauge symmetries imply powerful selection rules for Yukawa couplings of charged matter fields. In particular, in MSSM-like models they correspond to discrete flavour sy...
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.
IBM: parameter symmetry, hidden symmetries and transformations of boson operators
International Nuclear Information System (INIS)
A symmetry of the parameter space of interacting boson models IBM-1 and IBM-2 is studied. The symmetry is associated with linear canonical transformations of boson operators, or, equivalently, with the existence of different realizations of the symmetry algebras of the models. The relevance of the parameter symmetry to physical observables is discussed. (Author)
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.)
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.)
DEFF Research Database (Denmark)
Beltoft, Vibe Meister; Nørby, Karin Kristiane
The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate three flavouring substances in the Flavouring Group Evaluation 35, Revision 1, using the Procedure in Commission Regulation (EC) No 1565/2000. The present ...
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)
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.
Hadron masses in QCD with one quark flavour
International Nuclear Information System (INIS)
One-flavour QCD - a gauge theory with SU(3) colour gauge group and a fermion in the fundamental representation - is studied by Monte Carlo simulations. The mass spectrum of hadronic bound states is investigated in a volume with extensions of L≅4.4r0(≅2.2 fm) at two different lattice spacings: a ≅0.37r0 (≅0.19 fm) and a≅ 0.27r0 (≅0.13 fm). The lattice action is Symanzik tree-level-improved Wilson action for the gauge field and (unimproved) Wilson action for the fermion. (orig.)
Oxidative flavour deterioration of fish oil enriched milk
DEFF Research Database (Denmark)
Bruni Let, Mette; Jacobsen, Charlotte; Frankel, E.N.;
2003-01-01
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......-% of n-3 fatty acids) and one with cod liver oil (26 wt-% of n-3 fatty acids). The effect of added calcium disodium ethylenediaminetetraacetate (EDTA) on oxidation was also investigated. Emulsions based on cod liver oil with a slightly elevated peroxide value (1.5 meq/kg) oxidised significantly faster...
$\\pi K$ 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, $L_4^r$...
Test of the flavour independence of αs
Buskulic, D.; Casper, D.; de Bonis, I.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Minard, M.-N.; Odier, P.; Pietrzyk, B.; Ariztizabal, F.; Chmeissani, M.; Crespo, J. M.; Efthymiopoulos, I.; Fernandez, E.; Fernandez-Bosman, M.; Gaitan, V.; Garrido, Ll.; Martinez, M.; Orteu, S.; Pacheco, A.; Padilla, C.; Palla, F.; Pascual, A.; Perlas, J. A.; Sanchez, F.; Teubert, F.; Creanza, D.; de Palma, M.; Farilla, A.; Iaselli, G.; Maggi, G.; Marinelli, N.; Natali, S.; Nuzzo, S.; Ranieri, A.; Raso, G.; Romano, F.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Bonvicini, G.; Cattaneo, M.; Comas, P.; Coyle, P.; Drevermann, H.; Engelhardt, A.; Forty, R. W.; Frank, M.; Girone, M.; Hagelberg, R.; Harvey, J.; Jacobsen, R.; Janot, P.; Jost, B.; Knobloch, J.; Lehraus, I.; Maggi, M.; Markou, C.; Martin, E. B.; Mato, P.; Meinhard, H.; Minten, A.; Miquel, R.; Oest, T.; Palazzi, P.; Pater, J. R.; Perrodo, P.; Pusztaszeri, J.-F.; Ranjard, F.; Rensing, P.; Rolandi, L.; Schlatter, D.; Schmelling, M.; Schneider, O.; Tejessy, W.; Tomalin, I. R.; Venturi, A.; Wachsmuth, H.; Wiedenmann, W.; Wildish, T.; Witzeling, W.; Wotschack, J.; Ajaltouni, Z.; Bardadin-Otwinowska, M.; Barres, A.; Boyer, C.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rossignol, J.-M.; Saadi, F.; Fearnley, T.; Hansen, J. B.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Kyriakis, A.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Zachariadou, K.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Bourdon, P.; Passalacqua, L.; Rougé, A.; Rumpf, M.; Tanaka, R.; Valassi, A.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Focardi, E.; Parrini, G.; Corden, M.; Delfino, M.; Georgiopoulos, C.; Jaffe, D. E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Pepe-Altarelli, M.; Dorris, S. J.; Halley, A. W.; Ten Have, I.; Knowles, I. G.; Lynch, J. G.; Morton, W. T.; O'Shea, V.; Raine, C.; Reeves, P.; Scarr, J. M.; Smith, K.; Smith, M. G.; Thompson, A. S.; Thompson, F.; Thorn, S.; Turnbull, R. M.; Becker, U.; Braun, O.; Geweniger, C.; Graefe, G.; Hanke, P.; Hepp, V.; Kluge, E. E.; Putzer, A.; Rensch, B.; Schmidt, M.; Sommer, J.; Stenzel, H.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Colling, D. J.; Dornan, P. J.; Konstantinidis, N.; Moneta, L.; Moutoussi, A.; Nash, J.; San Martin, G.; Sedgbeer, J. K.; Stacey, A. M.; Dissertori, G.; Girtler, P.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Bowdery, C. K.; Brodbeck, T. J.; Colrain, P.; Crawford, G.; Finch, A. J.; Foster, F.; Hughes, G.; Sloan, T.; Whelan, E. P.; Williams, M. I.; Galla, A.; Greene, A. M.; Kleinknecht, K.; Quast, G.; Raab, J.; Renk, B.; Sander, H.-G.; Wanke, R.; Zeitnitz, C.; Aubert, J. J.; Bencheikh, A. M.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Calvet, D.; Carr, J.; Diaconu, C.; Etienne, F.; Thulasidas, M.; Nicod, D.; Payre, P.; Rousseau, D.; Talby, M.; Abt, I.; Assmann, R.; Bauer, C.; Blum, W.; Brown, D.; Dietl, H.; Dydak, F.; Gotzhein, C.; Jakobs, K.; Kroha, H.; Lütjens, G.; Lutz, G.; Männer, W.; Moser, H.-G.; Richter, R.; Rosado-Schlosser, A.; Schwarz, A. S.; Settles, R.; Seywerd, H.; Stierlin, U.; Denis, R. St.; Wolf, G.; Alemany, R.; Boucrot, J.; Callot, O.; Cordier, A.; Courault, F.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Jacquet, M.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Musolino, G.; Nikolic, I.; Park, H. J.; Park, I. C.; Schune, M.-H.; Simion, S.; Veillet, J.-J.; Videau, I.; Abbaneo, D.; Azzurri, P.; Bagliesi, G.; Batignani, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Ciulli, V.; Dell'Orso, R.; Ferrante, I.; Foà, L.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P. S.; Messineo, A.; Rizzo, G.; Sanguinetti, G.; Sciabà, A.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Triggiani, G.; Vannini, C.; Verdini, P. G.; Walsh, J.; Betteridge, A. P.; Blair, G. A.; Bryant, L. M.; Gao, Y.; Green, M. G.; Johnson, D. L.; Medcalf, T.; Mir, Ll. M.; Strong, J. A.; Bertin, V.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Edwards, M.; Maley, P.; Norton, P. R.; Thompson, J. C.; Bloch-Devaux, B.; Colas, P.; Duarte, H.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Marx, B.; Perez, P.; Rander, J.; Renardy, J.-F.; Rosowsky, A.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Si Mohand, D.; Trabelsi, A.; Vallage, B.; Johnson, R. P.; Kim, H. Y.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Beddall, A.; Booth, C. N.; Boswell, R.; Cartwright, S.; Combley, F.; Dawson, I.; Koksal, A.; Letho, M.; Newton, W. M.; Rankin, C.; Thompson, L. F.; Böhrer, A.; Brandt, S.; Cowan, G.; Feigl, E.; Grupen, C.; Lutters, G.; Minguet-Rodriguez, J.; Rivera, F.; Saraiva, P.; Smolik, L.; Stephan, F.; Bosisio, L.; Della Marina, R.; Ganis, G.; Giannini, G.; Gobbo, B.; Pitis, L.; Ragusa, F.; Rothberg, J.; Wasserbaech, S.; Armstrong, S. R.; Bellantoni, L.; Elmer, P.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; González, S.; Grahl, J.; Harton, J. L.; Hayes, O. J.; Hu, H.; McNamara, P. A.; Nachtman, J. M.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Schmitt, M.; Scott, I. J.; Sharma, V.; Turk, J. D.; Walsh, A. M.; Weber, F. V.; Wu, Sau Lan; Wu, X.; Yamartino, J. M.; Zheng, M.; Zobernig, G.; Aleph Collaboration
1995-02-01
Using about 950000 hadronic events collected during 1991 and 1992 with the ALEPH detector, the ratios r b = {α sb}/{α sudsc} and r uds = {α suds}/{α scb} have been measured in order to test the flavour independence of the strong coupling constant αs. The analysis is based on event-shape variables using the full hadronic sample, two b-quark samples enriched by lepton tagging and lifetime tagging, and a light-quark sample enriched by lifetime antitagging. The combined results are rb = 1.002±0.023 and ruds = 0.971 ± 0.023.
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.)
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. ...
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.
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.
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.
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...
“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
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)
Liu, Jing
were characterised by floral and fruity flavours, such as banana, peach/apricot and strawberry, while the remainder were mainly described by less desirable flavours for white wine, such as chemical, cheese and rooibos/smoke. Partial least squares regression of the sensory and instrumental analyses...
The minimal flavour violation benchmark in view of the latest LHCb data
International Nuclear Information System (INIS)
We derive the consequences of the MFV hypothesis for ΔF=1 flavour observables based on the latest LHCb data. Any future measurement beyond the MFV bounds and relations unambiguously indicates the existence of new flavour structures next to the Yukawa couplings of the Standard Model.
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
Formulae for flavour neutrino masses and its application to texture two zeros
Kitabayashi, Teruyuki
2015-01-01
We demonstrate the usefulness of flavour neutrino masses expressed in terms of $M_{ee},M_{e\\mu}$ and $M_{e\\tau}$. The analytical expressions for the flavour neutrino masses, mass eigenstates and physical CP-violating Majorana phases for texture two zeros are obtained exactly.
DEFF Research Database (Denmark)
Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister;
candidate substance spilanthol [FL-no: 16.121] is a branched chain unsaturated aliphatic amide from chemical group 30. The substance has been presented with specification of the stereoisomeric composition. The candidate substance was assigned to structural class III, according to the decision tree approach......, the Panel was requested to evaluate one flavouring substance in the Flavouring Group Evaluation 303, using the Procedure as referred to in the Commission Regulation (EC) No 1565/2000. The flavouring substance belongs to chemical group 30, Annex I of the Commission Regulation (EC) No 1565/2000. The....... In the absence of more precise information that would enable the Panel to make a more realistic estimate of the intakes of the flavouring substances, the Panel has decided also to perform an estimate of the daily intakes per person using a “modified Theoretical Added Maximum Daily Intake” (m...
Deppisch, Frank F; Patra, Sudhanwa; Sahu, Narendra; Sarkar, Utpal
2014-01-01
We propose a class of left-right symmetric models (LRSMs) with spontaneous D parity breaking, where SU(2)_R breaks at the TeV scale while discrete left-right symmetry breaks around 10^9 GeV. By embedding this framework in a non-supersymmetric SO(10) Grand Unified Theory (GUT) with Pati-Salam symmetry as the highest intermediate breaking step, we obtain g_R / g_L ~ 0.6 between the right- and left-handed gauge couplings at the TeV scale. This leads to a suppression of beyond the Standard Model phenomena induced by the right-handed gauge coupling. Here we focus specifically on the consequences for neutrinoless double beta decay, low energy lepton flavour violation and LHC signatures due to the suppressed right handed currents. Interestingly, the reduced g_R allows us to interpret an excess of events observed recently in the range of 1.9 TeV to 2.4 TeV by the CMS group at the LHC as the signature of a right handed gauge boson in LRSMs with spontaneous D parity breaking. Moreover, the reduced right-handed gauge co...
Flavour tagging methods used in the ATLAS B physics program
International Nuclear Information System (INIS)
Full text: Major tasks of the ATLAS B-physics program are the measurement of the B0s oscillations and the weak mixing phase Φs. The B0s oscillation parameter δms will be measured by using the hadronic decay channels B0s → Ds(φ, π)π and B0s → Ds(φ, π)a1, while the weak mixing phase Ψs uses the channel B0s → J/ψ(μ+, μ-)φ, with φ → K+K-. For an accurate measurement the determination of the B0s flavour at production time is crucial. Various methods for flavour tagging like e.g. opposite side soft muon tagging or same side jet charge tagging are studied and possible calibration channels are explored. Also the combination of different kinematic observables in order to receive event-by-event mistag rates using a multivariate analysis will be presented. (author)
Extended shelf life flavoured dairy drink using dissolved carbon dioxide.
Ravindra, Menon Rekha; Rao, K Jayaraj; Nath, B Surendra; Ram, Chand
2014-01-01
Cardamom flavoured dairy beverage prepared using standardized method was carbonated in glass bottles. Carbonation at 50 psi pressure for 30 s was recommended. The pasteurized flavoured drink, carbonated or otherwise was evaluated for sensory, chemical and microbial quality during its refrigerated storage. The uncarbonated control samples were found to be sensorily acceptable up to 14 days, while the carbonated beverage remained acceptable up to 30 days. Carbonation of drink significantly affected the pH and acidity of product without reducing its acceptability. Carbonation resulted in inhibition of microbes, the effect was pronounced on psychrotrophic count. There was a linear but marginal increase in the pH of the carbonated samples till the 17(th) day of storage; the values diminished thereafter. The carbonated samples also had significantly reduced contents of FFA and soluble nitrogen compared to that of uncarbonated control samples as storage progressed beyond 10 days and this was attributed to inhibited microbial growth. PMID:24426058
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.)
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)
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
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 ...
International Nuclear Information System (INIS)
In unpolarized cross sections constraints imposed by symmetries produce only quantitative changes which, in the absence of the precise knowledge of dynamics, cannot be used to test the validity of those symmetries. In polarization observables, in sharp contrast, imposition of symmetries produces qualitative changes, such as the vanishing of some observables or linear relationships among observables, which can be used to check the validity of symmetries without a detailed knowledge of dynamics. Such polarization observables can also separate the different constraints caused by different symmetries imposed simultaneously. This is illustrated for the two cases when Lorentz invariance and parity conservation, and Lorentz invariance and time reversal invariance, respectively, hold. It is also shown that it is impossible to construct, in any reaction in atomic, nuclear, or particle physics, a null experiment that would unambiguously test the validity of time-reversal invariance independently of dynamical assumptions. Finally, for a general quantum mechanical system undergoing a process, it is shown that one can tell from measurements on this system whether or not the system is characterized by quantum numbers the existence of which is unknown to the observer, even though the detection equipment used by the observer is unable to distinguish among the various possible values of the secret quantum number and hence always averages over them. This allows us to say whether the spin of a particle in a reaction is zero or not even if they can measure nothing about that particle's polarization. 5 references
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.
Yi-Nan, Fang; Guo-Hui, Dong; Duan-Lu, Zhou; Chang-Pu, Sun
2016-04-01
Symmetry is conventionally described in a polarized manner that the system is either completely symmetric or completely asymmetric. Using group theoretical approach to overcome this dichotomous problem, we introduce the degree of symmetry (DoS) as a non-negative continuous number ranging from zero to unity. DoS is defined through an average of the fidelity deviations of Hamiltonian or quantum state over its transformation group G, and thus is computable by making use of the completeness relations of the irreducible representations of G. The monotonicity of DoS can effectively probe the extended group for accidental degeneracy while its multi-valued natures characterize some (spontaneous) symmetry breaking. Supported by the National Natural Science Foundation of China under Grant Nos. 11421063, 11534002, 11475254 and the National 973 Program under Grant Nos. 2014CB921403, 2012CB922104, and 2014CB921202
International Nuclear Information System (INIS)
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
Binary Tetrahedral Flavor Symmetry
Eby, David A
2013-01-01
A study of the T' Model and its variants utilizing Binary Tetrahedral Flavor Symmetry. We begin with a description of the historical context and motivations for this theory, together with some conceptual background for added clarity, and an account of our theory's inception in previous works. Our model endeavors to bridge two categories of particles, leptons and quarks, a unification made possible by the inclusion of additional Higgs particles, shared between the two fermion sectors and creating a single coherent system. This is achieved through the use of the Binary Tetrahedral symmetry group and an investigation of the Tribimaximal symmetry evidenced by neutrinos. Our work details perturbations and extensions of this T' Model as we apply our framework to neutrino mixing, quark mixing, unification, and dark matter. Where possible, we evaluate model predictions against experimental results and find excellent matching with the atmospheric and reactor neutrino mixing angles, an accurate prediction of the Cabibb...
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...
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...
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
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
2016-01-01
We construct discrete symmetry transformations for deformed relativistic kinematics based on group valued momenta. We focus on the specific example of kappa-deformations of the Poincare 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 kappa to be derived via precision measurements of discrete symmetries and CPT.
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.
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.
International Nuclear Information System (INIS)
We review the current status of heavy-quark symmetry and its applications to weak decays of hadrons containing a single heavy quark. After an introduction to the underlying physical ideas, we discuss in detail the formalism of the heavy-quark effective theory, including a comprehensive treatment of symmetry breaking corrections. We then illustrate some nonperturbative approaches, which aim at a dynamical, QCD-based calculation of the universal form factors of the effective theory. The main focus is on results obtained using QCD sum rules. Finally, we perform an essentially model-independent analysis of semileptonic B meson decays in the context of the heavy-quark effective theory. ((orig.))
International Nuclear Information System (INIS)
The vanishing of the one-loop string cosmological constant in nontrivial nonsupersymmetric backgrounds can be understood by viewing the path integral as an inner product of orthogonal wave functions. For special backgrounds the string theory has an extra symmetry, expressed as a transformation on moduli space. When left- and right-moving wave functions transform in different representations of this symmetry the cosmological constant must vanish. Specific examples of the mechanism are given at one loop for theories in two and four dimensions. Various suggestions are made for the higher loop extension of this idea. (orig.)
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.
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.
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
International Nuclear Information System (INIS)
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 β-enhanced threshold corrections which can be sizeable if tan β 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 yμ/ys=9/2 or 6 or yτ/yb=3/2 in SU(5). Furthermore, we study a special class of quark mass matrix textures for small tan β where θu13=θd13=0. We derive sum rules for the quark mixing parameters and find a simple relation between the two phases δu12 and δd12 and the right unitarity triangle angle α which suggests a simple phase structure for the quark mass matrices where one matrix element is purely imaginary and the remaining ones are purely real. To complement the aforementioned
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
Introduction to chiral symmetry
International Nuclear Information System (INIS)
These lectures are an attempt to a pedagogical introduction into the elementary concepts of chiral symmetry in nuclear physics. Effective chiral models such as the linear and nonlinear sigma model will be discussed as well as the essential ideas of chiral perturbation theory. Some applications to the physics of ultrarelativistic heavy ion collisions will be presented
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.
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.)
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...
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...
Release of peppermint flavour compounds from chewing gum: effect of oral functions
DEFF Research Database (Denmark)
Haahr, Anne-Mette; Bardow, A.; Thomsen, C.E.; Jensen, S.B.; Nauntofte, B.; Bakke, M.; Adler-Nissen, Jens; Bredie, W.L.P.
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......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...
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.
An MCMC study of general squark flavour mixing in the MSSM
Herrmann, Björn; Fuks, Benjamin; Mahmoudi, Farvah; O'Leary, Ben; Porod, Werner; Sekmen, Sezen; Strobbe, Nadja
2015-01-01
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.
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.
Mixed symmetric baryon multiplets in large $N_c$ QCD: two and three flavours
Matagne, N
2011-01-01
We propose a new method to study mixed symmetric multiplets of baryons in the context of the $1/N_c$ expansion approach. The simplicity of the method allows to better understand the role of various operators acting on spin and flavour degrees of freedom. The method is tested on two and three flavours. It is shown that the spin and flavour operators proportional to the quadratic invariants of SU$_S$(2) and SU$_F$(3) respectively are dominant in the mass formula.
Development of ginger-flavoured soya milk ice cream : Comparison of data analysis methods
Wiwat Wangcharoen
2012-01-01
Sucrose at the concentration of 6 and 7% (w/w) and ginger extract at the concentration of 4 and 5% (w/w) were added to ginger-flavoured soya milk ice cream recipes to determine the consumer acceptablility. One hundred consumers were requested to taste four samples of ginger-flavoured soya milk ice cream and rate the intensity of ginger flavour, sweetness, richness and smoothness, together with their indication for ideal intensity of these attributes as well as their preference of each sampl...
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.
Resonant spin-flavour precession of neutrinos and pulsar velocities
International Nuclear Information System (INIS)
Young pulsars are known to exhibit large space velocities, up to 103 km/s. We propose a new mechanism for the generation of these large velocities based on an asymmetric emission of neutrinos during the supernova explosion. The mechanism involves the resonant spin-flavour precession of neutrinos with a transition magnetic moment in the magnetic field of the supernova. The asymmetric emission of neutrinos is due the distortion of the resonance surface by matter polarization effects in the supernova magnetic field. The requisite values of the field strengths and neutrino parameters are estimated for various neutrino conversions caused by their Dirac or Majorana-type transition magnetic moments. (author). 30 refs, 1 tab
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.
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 Independent Search for Neutral Higgs Bosons at LEP
Achard, P; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Baldew, S V; Banerjee, S; Banerjee, Sw; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiefari, G; Cifarelli, Luisa; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; van Dalen, J A; De Asmundis, R; Déglon, P L; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau, D; Duda, M; Echenard, B; Eline, A; El-Hage, A; El-Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, F; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Guida, M; van Gulik, R; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Käfer, D; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kräber, M H; Krämer, R W; Krüger, A; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Levtchenko, M; Levchenko, P M; Li, C; Likhoded, S; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Luci, C; Luminari, L; Lustermann, W; Ma Wen Gan; Malgeri, L; Malinin, A; Maña, C; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Novák, T; Nowak, H; Ofierzynski, R A; Organtini, G; Pal, I; Palomares, C; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofev, D; Prokofiev, D O; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P A; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosenbleck, C; Rosier-Lees, S; Roth, S; Rubio, J A; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Schäfer, C; Shchegelskii, V; Schopper, Herwig Franz; Schotanus, D J; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A V; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, Ludwig; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Ulbricht, J; Valente, E; Van de Walle, R T; Vásquez, R; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, Gert M; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, Q; Wang, X L; Wang, Z M; Weber, M; Wienemann, P; Wilkens, H; Wynhoff, S; Xia, L; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhao, J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zichichi, A; Zimmermann, B; Zöller, M
2004-01-01
A flavour independent search for the CP-even and CP-odd neutral Higgs bosons h and A is performed in 624/pb of data collected with the L3 detector at LEP at centre-of-mass energies between 189 and 209GeV. Higgs boson production through the e^+e^- -> Z h and the e^+e^- ->h A processes is considered and decays of the Higgs bosons into hadrons are studied. No significant signal is observed and 95% confidence level limits on the hZZ and hAZ couplings are derived as a function of the Higgs boson masses. Assuming the Standard Model cross section for the Higgs-strahlung process and a 100% branching fraction into hadrons, a 95% confidence level lower limit on the mass of the Higgs boson is set at 110.3GeV.
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.
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.
Fazzini, Davide; Khanji, Basem
In this thesis new developments of $\\textit{Flavour Tagging}$ algorithms for the $LHCb$ experiment are presented. The $\\textit{Flavour Tagging}$ is a very usefull tool which allows to determine the flavour of the reconstructed particles, such as the $B^0$ mesons. A correctly identification of the flavour is fundamental in certain measurements such as time-dependent $CP$ violation asymmetries or the $B^0 \\leftrightarrow \\overline{B}^0$ oscillations. Both these type of measurements are exploited by LHCb experiment in the research of new physics beyond the Standard Model. The new developments achieved in this work concern an optimization of the $\\textit{Same Side Tagger}$ algorithms, using protons and pions correlated in charge with the signal $B^0$ to infer its initial flavour. Then two combinations are implemented: the first is a combination of the $\\textit{SS Pion Tagger}$ ($SS\\pi$) and the $\\textit{SS Proton Tagger}$ ($SSp$) in a unique $\\textit{Same Side}$ ($SS$) tagging algorithm; the second one is the fi...
On Symmetries in Optimal Control
van der Schaft, A. J.
1986-01-01
We discuss the use of symmetries in solving optimal control problems. In particular a procedure for obtaining symmetries is given which can be performed before the actual calculation of the optimal control and optimal Hamiltonian.
Dynamical symmetry and shape coexistence
International Nuclear Information System (INIS)
A general discussion is given of extending the Fermion Dynamical Symmetry Model to describe shape coexistence. The theory is applied to the description of superdeformation and normal deformations through alternative dynamical symmetries
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.)
Concurrent symmetries: the interplay between local and global molecular symmetries.
Echeverría, Jorge; Carreras, Abel; Casanova, David; Alemany, Pere; Alvarez, Santiago
2011-01-01
We analyze in this article the degree to which different groups of atoms retain local symmetries when assembled in a molecule. This study is carried out by applying continuous symmetry measures to several families of mixed sandwiches, a variety of piano-stool molecules, and several organic groups. An analysis of the local symmetry of the electron density shows that, sandwiched between two regions of different symmetry that correspond to the ligand sets, its symmetry is cylindrical at the central metal atom. PMID:21207632
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.
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…
Charge independence and charge symmetry
International Nuclear Information System (INIS)
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. (author). 145 refs., 3 tabs., 11 figs
The Geometry of Noncommutative Symmetries
International Nuclear Information System (INIS)
We discuss the notion of noncommutative symmetries based on Hopf algebras in the geometric models constructed within the framework of non-commutative geometry. We introduce and discuss several notions of non-commutative symmetries and outline the construction specific examples, for instance, finite algebras and the application of symmetries in the derivation of the Dirac operator for the noncommutative torus. (author)
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.
Stability of aspartame and neotame in pasteurized and in-bottle sterilized flavoured milk.
Kumari, Anuradha; Choudhary, Sonika; Arora, Sumit; Sharma, Vivek
2016-04-01
Analytical high performance liquid chromatography (HPLC) conditions were standardized along with the isolation procedure for separation of aspartame and neotame in flavoured milk (pasteurized and in-bottle sterilized flavoured milk). The recovery of the method was approximately 98% for both aspartame and neotame. The proposed HPLC method can be successfully used for the routine determination of aspartame and neotame in flavoured milk. Pasteurization (90 °C/20 min) resulted in approximately 40% loss of aspartame and only 8% of neotame was degraded. On storage (4-7°C/7 days) aspartame and neotame content decreased significantly (Paspartame; however, 50.50% of neotame remained intact. During storage (30 °C/60 days) neotame content decreased significantly (Paspartame in both pasteurized and in-bottle sterilized flavoured milk. PMID:26593524
Claisen, Cope and Related Rearrangements in the Synthesis of Flavour and Fragrance Compounds
Janusz Nowicki
2000-01-01
A review of the use of the Claisen, Cope and related [3,3]-sigmatropic rearrangements, sequential ("tandem") sigmatropic rearrangements and the "ene" reaction in the syntheses of flavour and fragrance compounds is presented.
DEFF Research Database (Denmark)
Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister; Lund, Pia; Binderup, Mona-Lise
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...... Panel concluded that the 14 substances [FL-no: 13.001, 13.002, 13.003, 13.005, 13.018, 13.019, 13.025, 13.038, 13.057, 13.062, 13.067, 13.068, 13.073 and 13.128] do not give rise to safety concerns at their levels of dietary intake, estimated on the basis of the MSDI approach....
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.
Conformal symmetries of spacetimes
International Nuclear Information System (INIS)
In this paper, we give a unified and global new approach to the study of the conformal structure of the three classical Riemannian spaces as well as of the six relativistic and non-relativistic spacetimes (Minkowskian, de Sitter, anti-de Sitter, and both Newton-Hooke and Galilean). We obtain general expressions within a Cayley-Klein framework, holding simultaneously for all these nine spaces, whose cycles (including geodesics and circles) are explicitly characterized in a new way. The corresponding cycle-preserving symmetries, which give rise to (Moebius-like) conformal Lie algebras, together with their differential realizations are then deduced without having to resort to solving the conformal Killing equations. We show that each set of three spaces with the same signature type and any curvature have isomorphic conformal algebras; these are related through an apparently new conformal duality. Laplace and wave-type differential equations with conformal algebra symmetry are finally constructed. (author)
A broken symmetry ontology: Quantum mechanics as a broken symmetry
International Nuclear Information System (INIS)
The author proposes a new broken symmetry ontology to be used to analyze the quantum domain. This ontology is motivated and grounded in a critical epistemological analysis, and an analysis of the basic role of symmetry in physics. Concurrently, he is led to consider nonheterogeneous systems, whose logical state space contains equivalence relations not associated with the causal relation. This allows him to find a generalized principle of symmetry and a generalized symmetry-conservation formalisms. In particular, he clarifies the role of Noether's theorem in field theory. He shows how a broken symmetry ontology already operates in a description of the weak interactions. Finally, by showing how a broken symmetry ontology operates in the quantum domain, he accounts for the interpretational problem and the essential incompleteness of quantum mechanics. He proposes that the broken symmetry underlying this ontological domain is broken dilation invariance
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.
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.
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.
Fabella, Raul V.
1997-01-01
We consider teams where information asymmetry (adverse selection and moral hazard) is minimized by entry point screening designed to produce homogenous membership and work group arrangements and job rotation that render effort at worst imperfectly observable. We show that under membership symmetry, budget balance and strict rationality, a self-enforcing Pareto efficient (cooperates) and envy-free solution is attainable if and only production technology is of a unique concave family. Even in t...
Dynamical Electroweak Symmetry Breaking
Czech Academy of Sciences Publication Activity Database
Hošek, Jiří; Smetana, Adam
Berlin: Springer, 2014, s. 17-28. ISBN 978-3-319-07072-8 R&D Projects: GA ČR GA202/06/0734; GA MŠk LA08015; GA MŠk LA08032 Institutional support: RVO:61389005 Keywords : dynamical electroweak symmetry breaking * top-quark condensation * neutriono condensation * strong Yukawa dynamics * flavor gauge dynamics Subject RIV: BE - Theoretical Physics
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.
Arashdeep Singh; Usha Bajwa
2014-01-01
Storage conditions were known to bring about some physicochemical changes in frozen foods. The present investigation was therefore carried out to examine the effect of storage period on the physicochemical, sensory and microbiological quality of bakery flavoured ice cream. Bakery flavoured ice cream incorporating cookies (plain and chocolate) and cakes (vanilla and chocolate) at 10 per cent level were prepared and subjected to 60 days of frozen storage and evaluated periodically...
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 search for new physics. Also, the lepton sector of the Standard Model has to be extended to describe the observed neutrino oscillations. ATLAS experiment searches for lepton flavour violation, new gauge boson allowing to unify quark and lepton fields, heavy charged and neutral leptons as well as for new phenomena in multiphoton final states are summarized in this document. The most recent results will be discussed and compared with existing results.
B(s)→eμ: search for lepton flavour violation at LHCb
Onderwater, Cornelis; Pellegrino, Antonio; Kappert, Rosa; Wiersema, Garbrand; van Veghel, Maarten(Nikhef National Institute for Subatomic Physics, Amsterdam, The Netherlands)
2016-01-01
The existence of three flavors of fundamental fermions is one of the great mysteries of the standard model of particle physics. At the same time it is at the basis of a variety of exciting phenomena, such as CP violation and neutrino flavor oscillations. Hints are mounting that the assumption of lepton universality and charged lepton flavour conservation, as currently incorporated in the standard model, may not be valid. We report on our test of charged lepton flavour conservation in the deca...
Mortality among flavour and fragrance chemical plant workers in the United States.
Thomas, T L
1987-01-01
Vital status on 1 January 1981 was determined for a cohort of 1412 white men employed in a flavour and fragrance chemical plant between 1945 and 1965 in order to investigate the risks from fatal diseases among men exposed to multiple chemicals in the manufacture of fragrances, flavours, aroma chemicals, and other organic substances. Cause specific standardised mortality ratios (SMRs) were calculated for the entire study population and for several subsets by likelihood of exposure to chemicals...
First results with two light flavours of quarks with maximally twisted mass
International Nuclear Information System (INIS)
We report on first results of an ongoing effort to simulate lattice QCD with two degenerate flavours of quarks by means of the twisted mass formulation tuned to maximal twist. By utilising recent improvements of the HMC algorithm, pseudo-scalar masses well below 300 MeV are simulated on volumes L3.T with T=2L and L>2 fm and at values of the lattice spacing af=2+1+1 flavours are discussed. (orig.)
Lepton flavour violation at high energies: the LHC and a Linear Collider
Teixeira, A M; Figueiredo, A J R; Romao, J C
2014-01-01
We discuss several manifestations of charged lepton flavour violation at high energies. Focusing on a supersymmetric type I seesaw, considering constrained and semi-constrained supersymmetry breaking scenarios, we analyse different observables, both at the LHC and at a future Linear Collider. We further discuss how the synergy between low- and high-energy observables can shed some light on the underlying mechanism of lepton flavour violation.
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.
Study of flavour compounds from orange juices by HS-SPME and GC-MS
Schmutzer, G.; Avram, V.; Covaciu, F.; Feher, I.; Magdas, A.; David, L.; Moldovan, Z.
2013-11-01
The flavour of the orange juices, which gives the taste and odour of the product, is an important criterion about the products quality for consumers. A fresh single strength and two commercial orange juices (obtained from concentrate) flavour profile were studied using a selective and sensitive gas chromatography - mass spectrometry (GC-MS) analytical system, after a solvent free, single step preconcentration and extraction technique, the headspace solid phase microextraction (HP-SPME). In the studied orange juices 55 flavour compounds were detected and classified as belonging to the esters, alcohols, ketones, monoterpenes and sesquiterpenes chemical families. The fresh single strength orange juice was characterized by high amount of esters, monoterpenes and sesquiterpenes. Limonene and valencene were the most abundant flavours in this fresh natural orange juice. Alcohols and ketones were found in higher concentration in the commercial orange juices made from concentrate, than in the single strength products. Nevertheless, in commercial juices the most abundant flavour was limonene and α-terpineol. The results highlight clear differences between fresh singles strength orange juice and juice from concentrate. The orange juices reconstructed from concentrate, made in Romania, present low quantity of flavour compounds, suggesting the absence or a low rearomatization process, but extraneous components were not detected.
Heavy-quark mass dependence in global PDF analyses and 3- and 4-flavour parton distributions
Energy Technology Data Exchange (ETDEWEB)
Martin, A.D. [University of Durham, Institute for Particle Physics Phenomenology, Durham (United Kingdom); Stirling, W.J. [University of Cambridge, Cavendish Laboratory, Cambridge (United Kingdom); Thorne, R.S. [University College London, Department of Physics and Astronomy, London (United Kingdom); Watt, G. [CERN, Theory Group, Physics Department, Geneva 23 (Switzerland)
2010-11-15
We study the sensitivity of our recent MSTW 2008 NLO and NNLO PDF analyses to the values of the charm- and bottom-quark masses, and we provide additional public PDF sets for a wide range of these heavy-quark masses. We quantify the impact of varying m{sub c} and m{sub b} on the cross sections for W, Z and Higgs production at the Tevatron and the LHC. We generate 3- and 4-flavour versions of the (5-flavour) MSTW 2008 PDFs by evolving the input PDFs and {alpha}{sub S} determined from fits in the 5-flavour scheme, including the eigenvector PDF sets necessary for calculation of PDF uncertainties. As an example of their use, we study the difference in the Z total cross sections at the Tevatron and LHC in the 4- and 5-flavour schemes. Significant differences are found, illustrating the need to resum large logarithms in Q{sup 2}/m{sub b}{sup 2} by using the 5-flavour scheme. The 4-flavour scheme is still necessary, however, if cuts are imposed on associated (massive) b-quarks, as is the case for the experimental measurement of Zb anti b production and similar processes. (orig.)
DEFF Research Database (Denmark)
Beltoft, Vibe Meister; Binderup, Mona-Lise; Frandsen, Henrik Lauritz; Lund, Pia; Nørby, Karin Kristiane
The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to consider evaluations of flavouring substances assessed since 2000 by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), and to decide whether further...... evaluation is necessary, as laid down in Commission Regulation (EC) No 1565/2000. The present opinion concerns a group of 26 sulphur-containing heterocyclic compounds evaluated by the JECFA at the 59th meeting in 2008. This revision is made due to the inclusion of one additional substance, 5-methyl-2...
On the stability of the parity symmetry of the scotogenic model
International Nuclear Information System (INIS)
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 Z2 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.
International Nuclear Information System (INIS)
This new edition of Prof. Strocchi's well received primer on rigorous aspects of symmetry breaking presents a more detailed and thorough discussion of the mechanism of symmetry breaking in classical field theory in relation with the Noether theorem. Moreover, the link between symmetry breaking without massless Goldstone bosons in Coulomb systems and in gauge theories is made more explicit in terms of the delocalized Coulomb dynamics. Furthermore, the chapter on the Higgs mechanism has been significantly expanded with a non-perturbative treatment of the Higgs phenomenon, at the basis of the standard model of particle physics, in the local and in the Coulomb gauges. Last but not least, a subject index has been added and a number of misprints have been corrected. From the reviews of the first edition: The notion of spontaneous symmetry breaking has proven extremely valuable, the problem is that most derivations are perturbative and heuristic. Yet mathematically precise versions do exist, but are not widely known. It is precisely the aim of his book to correct this unbalance. - It is remarkable to see how much material can actually be presented in a rigorous way (incidentally, many of the results presented are due to Strocchi himself), yet this is largely ignored, the original heuristic derivations being, as a rule, more popular. - At each step he strongly emphasizes the physical meaning and motivation of the various notions introduced, a book that fills a conspicuous gap in the literature, and does it rather well. It could also be a good basis for a graduate course in mathematical physics. It can be recommended to physicists as well and, of course, for physics/mathematics libraries. J.-P. Antoine, Physicalia 28/2, 2006 Strocchi's main emphasis is on the fact that the loss of symmetric behaviour requires both the non-symmetric ground states and the infinite extension of the system. It is written in a pleasant style at a level suitable for graduate students in
Discrete Family Symmetry from F-Theory GUTs
Karozas, Athanasios; Leontaris, George K; Meadowcroft, Andrew
2014-01-01
We consider realistic F-theory GUT models based on discrete family symmetries $A_4$ and $S_3$, combined with $SU(5)$ GUT, comparing our results to existing field theory models based on these groups. We provide an explicit calculation to support the emergence of the family symmetry from the discrete monodromies arising in F-theory. We work within the spectral cover picture where in the present context the discrete symmetries are associated to monodromies among the roots of a five degree polynomial and hence constitute a subgroup of the $S_5$ permutation symmetry. We focus on the cases of $A_4$ and $S_3$ subgroups, motivated by successful phenomenological models interpreting the fermion mass hierarchy and in particular the neutrino data. More precisely, we study the implications on the effective field theories by analysing the relevant discriminants and the topological properties of the polynomial coefficients, while we propose a discrete version of the doublet-triplet splitting mechanism.
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.
Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister; Lund, Pia; Binderup, Mona-Lise; Frandsen, Henrik Lauritz
2012-01-01
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 Commission Regulation (EC) No 1565/2000. None of the substances were considered to have genotoxic potential. The substances were evaluated through a stepwise approach (the Procedure) that integrates informati...
On the Isomorphic Description of Chiral Symmetry Breaking by Non-Unitary Lie Groups
Bietenholz, Wolfgang
2009-01-01
It is well-known that chiral symmetry breaking ($\\chi$SB) in QCD with $N_{f}=2$ light quark flavours can be described by orthogonal groups as $O(4) \\to O(3)$, due to local isomorphisms. Here we discuss the question how specific this property is. We consider generalised forms of $\\chi$SB involving an arbitrary number of light flavours of continuum or lattice fermions, in various representations. We search systematically for isomorphic descriptions by non-unitary, compact Lie groups. It turns out that there are a few alternative options in terms of orthogonal groups, while we did not find any description entirely based on symplectic or exceptional Lie groups. If we adapt such an alternative as the symmetry breaking pattern for a generalised Higgs mechanism, we may consider a Higgs particle composed of bound fermions and trace back the mass generation to $\\chi$SB. In fact, some of the patterns that we encounter appear in technicolour models. In particular if one observes a Higgs mechanism that can be expressed i...
Discrete Family Symmetry from F-Theory GUTs
Karozas, Athanasios; King, Stephen; Leontaris, George; Meadowcroft, Andrew(School of Physics and Astronomy, University of Southampton, SO17 1BJ, Southampton, U.K.)
2014-01-01
We consider realistic F-theory GUT models based on discrete family symmetries $A_4$ and $S_3$, combined with $SU(5)$ GUT, comparing our results to existing field theory models based on these groups. We provide an explicit calculation to support the emergence of the family symmetry from the discrete monodromies arising in F-theory. We work within the spectral cover picture where in the present context the discrete symmetries are associated to monodromies among the roots of a five degree polyno...
González Tomás, Luis; Tárrega, Amparo; Costell, Elvira
2005-01-01
Flavour release and perception are complex processes in which different physico-chemical and physiological phenomena may be involved 1. Whereas flavour release is mainly governed by chemical and/or physical interactions between flavour compounds and the food matrix 2, perception is strongly influenced by physiological factors like mouth volume, saliva flow rate and air flow rate through the mouth and nose 3. In the framework of COST 921 action, the main objective of this work was to study the...