Continuous media interpretation of supersymmetric Wess-Zumino type models
Letelier, P.S. [Universidade Estadual de Campinas (Brazil). Departamento de Matematica Aplicada; Zanchin, V.T. [Departamento de Fisica-CCNE, Universidade Federal de Santa Maria, 97119, Santa Maria, R.S. (Brazil)
1995-02-20
Supersymmetric Wess-Zumino type models are considered as classical material media that can be interpreted as fluids of ordered strings with heat flow along the strings, or a mixture of fluids of ordered strings with either a cloud of particles or a flux of directed radiation. ((orig.))
Inflation in Wess--Zumino Models
Halyo, Edi
2010-01-01
We show that a class of Wess--Zumino models lead to inflation in supersymmetry and supergravity. This is due to the existence of a classically flat direction generic to these models. The pseudomodulus that parametrizes this flat direction is the inflaton and obtains a small mass due to either one--loop or supergravity corrections giving rise to slow--roll inflation. At the end of inflation, the fields roll to a supersymmetric vacuum that arises from explicit R symmetry breaking.
Intersoliton forces in the Wess-Zumino model
Portugues, R; Portugues, Ruben; Townsend, Paul K.
2002-01-01
The spectrum of supersymmetric domain wall solitons of the Wess-Zumino model is known to be discontinuous across a curve (of marginal stability) in the moduli space of quartic superpotentials. Here we show how this phenomenom can be understood from the behavior of the long-range inter-soliton force.
Wess-Zumino-Witten model off criticality
Cabra, D C
1994-01-01
We study the renormalization group flow properties of the Wess-Zumino-Witten model in the region of couplings between $g^2=0$ and $g^2=4\\pi/k$, by evaluating the two-loop Zamolodchikov's $c$-function. We also discuss the region of negative couplings.
Carneiro, D F; Sampaio, M D; Nemes, M C
2003-01-01
We compute the three loop $\\beta$ function of the Wess-Zumino model to motivate implicit regularization (IR) as a consistent and practical momentum-space framework to study supersymmetric quantum field theories. In this framework which works essentially in the physical dimension of the theory we show that ultraviolet are clearly disantangled from infrared divergences. We obtain consistent results which motivate the method as a good choice to study supersymmetry anomalies in quantum field theories.
Spontaneous supersymmetry breaking in the two-dimensional N=1 Wess-Zumino model
Steinhauer, Kyle
2014-01-01
We study the phase diagram of the two-dimensional N=1 Wess-Zumino model on the lattice using Wilson fermions and the fermion loop formulation. We give a complete nonperturbative determination of the ground state structure in the continuum and infinite volume limit. We also present a determination of the particle spectrum in the supersymmetric phase, in the supersymmetry broken phase and across the supersymmetry breaking phase transition. In the supersymmetry broken phase we observe the emergence of the Goldstino particle.
Spontaneous supersymmetry breaking in the 2d N=1 Wess-Zumino model
Baumgartner, David; Wenger, Urs
2013-01-01
We study the phase diagram of the two-dimensional N=1 Wess-Zumino model using Wilson fermions and the fermion loop formulation. We give a complete non-perturbative determination of the ground state structure in the continuum and infinite volume limit. We also present a determination of the particle spectrum in the supersymmetric phase, in the supersymmetry broken phase and across the supersymmetry breaking phase transition. In the supersymmetry broken phase we observe the emergence of the Goldstino particle.
Wess-Zumino-Witten Model for Galilean Conformal Algebra
Chakraborty, Somdeb
2012-01-01
In this note, we construct a Wess-Zumino-Witten model based on the Galilean conformal algebra in 2-spacetime dimensions, which is a nonrelativistic analogue of the relativistic conformal algebra. We obtain exact background corresponding to \\sigma-models in six dimensions (the dimension of the group manifold) and a central charge c=6. We carry out a Sugawara type construction to verify the conformal invariance of the model. Further, we discuss the feasibility of the background obtained as a physical spacetime metric.
Wess-Zumino Terms for the Deformed Skyrme Model
Neves, C; Neves, Clifford; Wotzasek, Clovis
2000-01-01
A formulation of Skyrme model as an embedded gauge theory with the constraint deformed away from the spherical geometry is proposed. The gauge invariant formulation is obtained firstly generalizing the intrinsic geometry of the model and then converting the constraint to first-class through an iterative Wess-Zumino procedure. The gauge invariant model is quantized via Dirac method for first-class system. A perturbative calculation provides new free parameters related to deformation that improve the energy spectrum obtained in earlier approaches.
Topological M-strings and supergroup Wess-Zumino-Witten models
Okazaki, Tadashi; Smith, Douglas J.
2016-09-01
We study the boundary conditions in topologically twisted Chern-Simons matter theories with the Lie 3-algebraic structure. We find that the supersymmetric boundary conditions and the gauge-invariant boundary conditions can be unified as complexified gauge-invariant boundary conditions which lead to supergroup Wess-Zumino-Witten (WZW) models. We propose that the low-energy effective field theories on the two-dimensional intersection of multiple M2-branes on a holomorphic curve inside K3 with two nonparallel M5-branes on the K3 are supergroup WZW models from the topologically twisted Bagger-Lambert-Gustavson model and the Aharony-Bergman-Jafferis-Maldacena model.
Wess-Zumino Model on Bosonic-Fermionic Noncommutative Superspace
Wang, Xu-Dong
2016-01-01
In our previous paper we construct a renormalizable Wess-Zumino action on BFNC superspace at the second order approximation of noncommutative parameters. The action contains about 200 terms which are necessary for renormalization. By removing chiral covariant derivatives and chiral coordinates we found that the BFNC Wess-Zumino action can be transformed to a simpler form which have manifest 1/2 supersymmetry. Based on this discovery, we can extend the BFNC Wess-Zumino action to the all order of noncommutative parameters. At first we introduce global symmetries, then obtain divergent operators in the effective action by using dimensional analysis, the next step is to construct all possible BFNC parameters, at the end we combine the BFNC parameters with the divergent operators. We present the explicit action up to the fourth order of noncommutative parameters. Because the action contain all possible divergent operators, it is renormalizable to all order in perturbative theory.
The two dimensional N=(2,2) Wess-Zumino Model in the Functional Renormalization Group Approach
Synatschke-Czerwonka, Franziska; Fischbacher, Thomas; Bergner, Georg
2010-01-01
We study the supersymmetric N=(2,2) Wess-Zumino model in two dimensions with the functional renormalization group. At leading order in the supercovariant derivative expansion we recover the nonrenormalization theorem which states that the superpotential has no running couplings. Beyond leading order the renormalization of the bare mass is caused by a momentum dependent wave function renormalization. To deal with the partial differential equations we have developed a numerical toolbox called F...
The Wess-Zumino Model and the $AdS_{4}/CFT_{3}$ Correspondence
Mück, W
1999-01-01
We consider the non-interacting massive Wess-Zumino model in four-dimensional anti-de Sitter space and show that the conformal dimensions of the corresponding boundary fields do not always satisfy the relation expected from superconformal invariance.
Renormalizability of N=1/2 Wess-Zumino model in superspace
Romagnoni, A
2003-01-01
In this letter we use the spurion field approach adopted in order to show that by adding F and F^2 terms to the original lagrangian, the N=1/2 Wess-Zumino model is renormalizable to all orders in perturbation theory. We reformulate in superspace language the proof given in the recent work in terms of component fields.
Exact lattice supersymmetry at the quantum level for N = 2 Wess-Zumino models in 1- and 2-dimensions
Asaka, Keisuke; D'Adda, Alessandro; Kawamoto, Noboru; Kondo, Yoshi
2016-08-01
Supersymmetric lattice Ward-Takahashi identities are investigated perturbatively up to two-loop corrections for super doubler approach of N = 2 lattice Wess-Zumino models in 1- and 2-dimensions. In this approach, notorious chiral fermion doublers are treated as physical particles and momentum conservation is modified in such a way that lattice Leibniz rule is satisfied. The two major difficulties to keep exact lattice supersymmetry are overcome. This formulation defines, however, nonlocal field theory. Nevertheless we confirm that exact supersymmetry on the lattice is realized for all supercharges at the quantum level. Delicate issues of associativity are also discussed.
Exact Lattice Supersymmetry at the Quantum Level for $N=2$ Wess-Zumino Models in 1- and 2-Dimensions
Asaka, Keisuke; Kawamoto, Noboru; Kondo, Yoshi
2016-01-01
Supersymmetric lattice Ward-Takahashi identities are investigated perturbatively up to two-loop corrections for super doubler approach of $N=2$ lattice Wess-Zumino models in 1- and 2-dimensions. In this approach notorious chiral fermion doublers are treated as physical particles and momentum conservation is modified in such a way that lattice Leibniz rule is satisfied. The two major difficulties to keep exact lattice supersymmetry are overcome. This formulation defines, however, nonlocal field theory. Nevertheless we confirm that exact supersymmetry on the lattice is realized for all supercharges at the quantum level. Delicate issues of associativity are also discussed.
A deformation of quantum affine algebra in squashed Wess-Zumino-Novikov-Witten models
Kawaguchi, Io; Yoshida, Kentaroh [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan)
2014-06-01
We proceed to study infinite-dimensional symmetries in two-dimensional squashed Wess-Zumino-Novikov-Witten models at the classical level. The target space is given by squashed S³ and the isometry is SU(2){sub L}×U(1){sub R}. It is known that SU(2){sub L} is enhanced to a couple of Yangians. We reveal here that an infinite-dimensional extension of U(1){sub R} is a deformation of quantum affine algebra, where a new deformation parameter is provided with the coefficient of the Wess-Zumino term. Then we consider the relation between the deformed quantum affine algebra and the pair of Yangians from the viewpoint of the left-right duality of monodromy matrices. The integrable structure is also discussed by computing the r/s-matrices that satisfy the extended classical Yang-Baxter equation. Finally, two degenerate limits are discussed.
Supersymmetry breaking on the lattice: the N=1 Wess-Zumino model
Baumgartner, David; Wenger, Urs
2011-01-01
We discuss spontaneous supersymmetry breaking in the N=1 Wess-Zumino model in two dimensions on the lattice using Wilson fermions and the fermion loop formulation. In that formulation the fermion sign problem related to the vanishing of the Witten index can be circumvented and the model can be simulated very efficiently using the recently introduced open fermion string algorithm. We present first results for the supersymmetry breaking phase transition and sketch the preliminary determination of a renormalised critical coupling in the continuum limit.
Supercurrent conservation in the lattice Wess-Zumino model with Ginsparg-Wilson fermions
Chen, Chen; Giedt, Joel; Paki, Joseph
2011-07-01
We study supercurrent conservation for the four-dimensional Wess-Zumino model formulated on the lattice. The formulation is one that has been discussed several times, and uses Ginsparg-Wilson fermions of the overlap (Neuberger) variety, together with an auxiliary fermion (plus superpartners), such that a lattice version of U(1)R symmetry is exactly preserved in the limit of vanishing bare mass. We show that the almost naive supercurrent is conserved at one loop. By contrast we find that this is not true for Wilson fermions and a canonical scalar action. We provide nonperturbative evidence for the nonconservation of the supercurrent in Monte Carlo simulations.
Supercurrent conservation in the lattice Wess-Zumino model with Ginsparg-Wilson fermions
Chen, Chen; Paki, Joseph
2011-01-01
We study supercurrent conservation for the four-dimensional Wess-Zumino model formulated on the lattice. The formulation is one that has been discussed several times, and uses Ginsparg-Wilson fermions of the overlap (Neuberger) variety, together with an auxiliary fermion (plus superpartners), such that a lattice version of U(1)_R symmetry is exactly preserved in the limit of vanishing bare mass. We show that the almost naive supercurrent is conserved at one loop. By contrast we find that this is not true for Wilson fermions and a canonical scalar action. We provide nonperturbative evidence for the nonconservation of the supercurrent in Monte Carlo simulations.
A Global Operator Approach to Wess-Zumino-Novikov-Witten models
Schlichenmaier, Martin
2007-11-01
We present a global operator approach to Wess-Zumino-Novikov models for compact Riemann surfaces of arbitrary genus g with N marked points. The approach is based on the multipoint Krichever-Novikov algebras of global meromorphic functions and vector fields, and the global algebras of affine type and their representations. Using the global Sugawara construction and the identification of a certain subspace of the vector field algebra with the tangent space to the moduli space of the geometric data, the Knizhnik-Zamalodchikov connection is defined. For fermionic representations it defines a projectively flat connection on the vector bundle of conformal blocks. The presented work is joint work with Oleg Sheinman.
Truncated Conformal Space Approach for Perturbed Wess-Zumino-Witten $SU(2)_k$ Models
Beria, M; Lepori, L; Konik, R M; Sierra, G
2013-01-01
We outline the application of the truncated conformal space approach (TCSA) to perturbations of $SU(2)_k$ Wess-Zumino-Witten theories. As examples of this methodology, we consider two distinct perturbations of $SU(2)_1$ and one of $SU(2)_2$. $SU(2)_1$ is first perturbed by its spin-1/2 field, a model which is equivalent to the sine-Gordon model at a particular value of its coupling $\\beta$. The sine-Gordon spectrum is correctly reproduced as well as the corresponding finite size corrections. We next study $SU(2)_1$ with a marginal current-current perturbation. The TCSA results can be matched to perturbation theory within an appropriate treatment of the UV divergences. Finally, we consider $SU(2)_2$ perturbed by its spin-1 field, which is equivalent to three decoupled massive Majorana fermions.In this case as well the TCSA reproduces accurately the known spectrum.
Wess-Zumino Inflation in Light of Planck
Croon, Djuna; Mavromatos, Nick E
2013-01-01
We discuss cosmological inflation in the minimal Wess-Zumino model with a single massive chiral supermultiplet. With suitable parameters and assuming a plausible initial condition at the start of the inflationary epoch, the model can yield scalar perturbations in the Cosmic Microwave Background (CMB) of the correct strength with a spectral index n_s ~ 0.96 and a tensor-to-scalar perturbation ratio r < 0.1, consistent with the Planck CMB data. We also discuss the possibility of topological inflation within the Wess-Zumino model, and the possibility of combining it with a seesaw model for neutrino masses. This would violate R-parity, but at such a low rate that the lightest supersymmetric particle would have a lifetime long enough to constitute the astrophysical cold dark matter.
Reflection Positivity of ${\\cal N}=1$ Wess-Zumino model on the lattice with exact U(1)$_R$ symmetry
Kikukawa, Yoshio
2010-01-01
By using overlap Majorana fermions, the ${\\cal N}=1$ chiral multiple can be formulated so that the supersymmetry is manifest and the vacuum energy is cancelled in the free limit, thanks to the bilinear nature of the free action. It is pointed out, however, that in this formulation the reflection positivity is violated in the bosonic part of the action, although it is satisfied in the fermionic part. It is found that the positivity of the spectral density of the bosonic two-point correlation function is ensured only for the spacial momenta $a | p_k | \\lesssim 1.72$ $(k=1,2,3)$. It is then argued that in formulating ${\\cal N}=1$ Wess-Zumino model with the overlap Majorana fermion, one may adopt a simpler nearest-neighbor bosonic action, discarding the free limit manifest supersymmetry. The model still preserves the would-be U(1)$_R$ symmetry and satisfies the reflection positivity.
Lattice Wess-Zumino model with Ginsparg-Wilson fermions: One-loop results and GPU benchmarks
Chen, Chen; Giedt, Joel
2010-01-01
We numerically evaluate the one-loop counterterms for the four-dimensional Wess-Zumino model formulated on the lattice using Ginsparg-Wilson fermions of the overlap (Neuberger) variety, such that a lattice version of U(1)_R symmetry is exactly preserved in the limit of vanishing bare mass. We confirm previous findings by other authors that at one loop there is no renormalization of the superpotential in the lattice theory. We discuss aspects of the simulation of this model that is planned for a follow-up work, and outline a strategy for nonperturbative improvement of the lattice supercurrent through measurements of \\susy\\ Ward identities. Related to this, some benchmarks for our graphics processing unit code are provided. An initial simulation finds a nearly vanishing vacuum expectation value for the auxiliary field, consistent with approximate supersymmetry.
Lattice Wess-Zumino model with Ginsparg-Wilson fermions: One-loop results and GPU benchmarks
Chen, Chen; Dzienkowski, Eric; Giedt, Joel
2010-10-01
We numerically evaluate the one-loop counterterms for the four-dimensional Wess-Zumino model formulated on the lattice using Ginsparg-Wilson fermions of the overlap (Neuberger) variety, together with an auxiliary fermion (plus superpartners), such that a lattice version of U(1)R symmetry is exactly preserved in the limit of vanishing bare mass. We confirm previous findings by other authors that at one loop there is no renormalization of the superpotential in the lattice theory, but that there is a mismatch in the wave-function renormalization of the auxiliary field. We study the range of the Dirac operator that results when the auxiliary fermion is integrated out, and show that localization does occur, but that it is less pronounced than the exponential localization of the overlap operator. We also present preliminary simulation results for this model, and outline a strategy for nonperturbative improvement of the lattice supercurrent through measurements of supersymmetry Ward identities. Related to this, some benchmarks for our graphics processing unit code are provided. Our simulation results find a nearly vanishing vacuum expectation value for the auxiliary field, consistent with approximate supersymmetry at weak coupling.
寇谡鹏
2002-01-01
Used the dimensional reduction in the sense of Parisi and Sourlas, the gauge fixing term of the four-dimensionalYang-Mills field without the theta term is reduced to a two-dimensional principal chiral model. By adding the θ term(θ = π), the two-dimensional principal chiral model changes into the two-dimensional level 1 Wess-Zumino-Novikov-Witten model. The non-trivial fixed point indicates that Yang-Mills theory at θ = π is a critical theory without massgap and confinement.
Twisted Supersymmetry in a Deformed Wess-Zumino Model in (2+1) Dimensions
Palechor, C; Quinto, A G
2016-01-01
Non-anticommutative deformations have been studied in the context of supersymmetry (SUSY) in three and four space-time dimensions, and the general picture is that highly nontrivial to deform supersymmetry in a way that still preserves some of its important properties, both at the formal algebraic level (e.g., preserving the associativity of the deformed theory) as well as at the physical level (e.g., maintaining renormalizability). The Hopf algebra formalism allows the definition of algebraically consistent deformations of SUSY, but this algebraic consistency does not guarantee that physical models build upon these structures will be consistent from the physical point of view. We will investigate a deformation induced by a Drinfel'd twist of the ${\\cal N}=1$ SUSY algebra in three space-time dimensions. The use of the Hopf algebra formalism allows the construction of deformed ${\\cal N}=1$ SUSY algebras that should still preserve a deformed version of supersymmetry. We will construct the simplest deformed versi...
Noncommutative Wess-Zumino-Witten actions and their Seiberg-Witten invariance
Lopez-Sarrion, Justo
2007-01-01
We analyze the noncommutative two-dimensional Wess-Zumino-Witten model and its properties under Seiberg-Witten transformations in the operator formulation. We prove that the model is invariant under such transformations even for the noncritical (non chiral) case, in which the coefficients of the kinetic and Wess-Zumino terms are not related. The pure Wess-Zumino term represents a singular case in which this transformation fails to reach a commutative limit. We also discuss potential implications of this result for bosonization.
Wess Zumino Couplings for Generalized $\\Sigma$ Orbifold Fixed-points
Ospina-Giraldo, J F
2000-01-01
The Wess-Zumino couplings for generalized sigma-orbifold fixed-points are presented and the generalized GS 6-form that encoding the complete sigma-standard gauge-gravitational-non standard gauge anomaly and its opposite inflow is derived.
Wess Zumino Couplings for Generalized Sigma Orbifold Fixed-points
Giraldo, Juan Fernando Ospina
2000-01-01
The Wess-Zumino couplings for generalized sigma-orbifold fixed-points are presented and the generalized GS 6-form that encoding the complete sigma-standard gauge-gravitational-non standard gauge anomaly and its opposite inflow is derived.
Classical dynamical variables for the Wess-Zumino matter Lagrangian
Domenech, G.; Levinas, M.; Umerez, N.
1989-05-01
We study the macroscopic behaviour of the Wess-Zumino matter multiplet. The Lagrangian and the energy-momentum tensor are obtained in terms of densities and velocities of an interacting fluid in N=1 supergravity background. Equations of motion and conditions for consistency are found.
Dimensional deconstruction and Wess-Zumino-Witten terms
Hill, Christopher T.; /Fermilab; Zachos, Cosmas K.; /Argonne
2004-11-01
A new technique is developed for the derivation of the Wess-Zumino-Witten terms of gauged chiral lagrangians. We start in D = 5 with a pure (mesonless) Yang-Mills theory, which includes relevant gauge field Chern-Simons terms. The theory is then compactified, and the effective D = 4 lagrangian is derived using lattice techniques, or ''deconstruction'', where pseudoscalar mesons arise from the lattice Wilson links. This yields the WZW term with the correct Witten coefficient by way of a simple heuristic argument. We discover a novel WZW term for singlet currents, that yields the full Goldstone-Wilczek current, and a U(1) axial current for the skyrmion, with the appropriate anomaly structures. A more detailed analysis is presented of the dimensional compactification of Yang-Mills in D = 5 into a gauged chiral lagrangian in D = 4, heeding the consistency of the D = 4 and D = 5 Bianchi identities. These dictate a novel covariant derivative structure in the D = 4 gauge theory, yielding a field strength modified by the addition of commutators of chiral currents. The Chern-Simons term of the pure D = 5 Yang-Mills theory then devolves into the correct form of the Wess-Zumino-Witten term with an index (the analogue of N{sub colors} = 3) of N = D = 5. The theory also has a Skyrme term with a fixed coefficient.
Exploring the Supersymmetric $\\sigma$ Model
De Oliveira-Imbiriba, B C
1999-01-01
The purpose of this work is to present some basic concepts about the non-linear sigma model in a simple and direct way. We start with showing the bosonic model and the Wess-Zumino-Witten term, making some comments about its topological nature, and its association with the torsion. It is also shown that to cancel the quantum conformal anomaly the model should obey the Einstein equations. We provide a quick introduction about supersymmetry in chapter 2 to help the understanding the supersymmetric extension of the model. In the last chapter we present the supersymmetric model and its equations of motion. Finally we work-out the two-supersymmetry case, introducing the chiral as well as the twisted chiral fields, expliciting the very specific $SU(2)\\otimes U(1)$ case.
Gukov, S G
1997-01-01
The evidently supersymmetric four-dimensional Wess-Zumino model with quenched disorder is considered at the one-loop level. The infrared fixed points of a beta-function form the moduli space $M = RP^2$ where two types of phases were found: with and without replica symmetry. While the former phase possesses only a trivial fixed point, this point become unstable in the latter phase which may be interpreted as a spin glass phase.
Renormalization aspects of N=1 Super Yang-Mills theory in the Wess-Zumino gauge
Capri, M A L; Guimaraes, M S; Justo, I F; Mihaila, L; Sorella, S P; Vercauteren, D
2014-01-01
The renormalization of N=1 Super Yang-Mills theory is analysed in the Wess-Zumino gauge, employing the Landau condition. An all orders proof of the renormalizability of the theory is given by means of the Algebraic Renormalization procedure. Only three renormalization constants are needed, which can be identified with the coupling constant, gauge field and gluino renormalization. Moreover, due to the non-linear realization of the supersymmetry in the Wess-Zumino gauge, the renormalization factor of the gauge field turns out to be different from that of the gluino, as explicitly shown through a three loop calculation.
Renormalization aspects of N = 1 Super Yang-Mills theory in the Wess-Zumino gauge
Capri, M.A.L.; Granado, D.R.; Guimaraes, M.S.; Justo, I.F.; Sorella, S.P.; Vercauteren, D. [UERJ-Universidade do Estado do Rio de Janeiro, Departamento de Fisica Teorica, Instituto de Fisica, Maracana, Rio de Janeiro (Brazil); Mihaila, L. [Karlsruhe Institute of Technology (KIT), Institut fuer Theoretische Teilchenphysik, Karlsruhe (Germany)
2014-04-15
The renormalization of N = 1 Super Yang-Mills theory is analyzed in the Wess-Zumino gauge, employing the Landau condition. An all-orders proof of the renormalizability of the theory is given by means of the Algebraic Renormalization procedure. Only three renormalization constants are needed, which can be identified with the coupling constant, gauge field, and gluino renormalization. The nonrenormalization theorem of the gluon-ghost-antighost vertex in the Landau gauge is shown to remain valid in N = 1 Super Yang-Mills. Moreover, due to the non-linear realization of the supersymmetry in the Wess-Zumino gauge, the renormalization factor of the gauge field turns out to be different from that of the gluino. These features are explicitly checked through a three-loop calculation. (orig.)
Wess-Zumino term for the AdS superstring and generalized Inoenue-Wigner contraction
Hatsuda, M
2003-01-01
We examine a Wess-Zumino term, written in a form of bilinear in superinvariant currents, for a superstring in anti-de Sitter (AdS) space, and derive a procedure for obtaining the correct flat limit. The standard Inoenue-Wigner contraction does not give the correct flat limit but, rather, gives zero. This erroneous result originates from the fact that the fermionic metric of the super-Poincare group is degenerate. We propose a generalization of the Inoenue-Wigner contraction from which a 'nondegenerate' super-Poincare group is derived from the super-AdS group. For this reason, this contraction gives the correct flat limit of this Wess-Zumino term. We also discuss the M-algebra obtained using this generalized Inoenue-Wigner contraction from osp(1|32). (author)
Supersymmetry breaking and gauge mediation in models with a generic superpotential
Kitano, Ryuichiro [Theoretical Division T-2, Los Alamos National Laboratory, NM 87545 (United States); Ookouchi, Yutaka [Perimeter Institute for Theoretical Physics, ON N2L2Y5 (Canada)], E-mail: yokochi@perimeterinstitute.ca
2009-05-04
We present a general scheme for finding or creating a metastable vacuum in supersymmetric theories. By using the formalism, we show that there is a parameter region where a metastable vacuum exists in the Wess-Zumino model coupled to messenger fields. This model serves as a perturbative renormalizable model of direct gauge mediation.
Two loop effective Kähler potential of (non-)renormalizable supersymmetric models
Nibbelink, S G; Nibbelink, Stefan Groot; Nyawelo, Tino S.
2006-01-01
We perform a supergraph computation of the effective Kaehler potential at one and two loops for general four dimensional N=1 supersymmetric theories described by arbitrary Kaehler potential, superpotential and gauge kinetic function. We only insist on gauge invariance of the Kaehler potential and the superpotential as we heavily rely on its consequences in the quantum theory. However, we do not require gauge invariance for the gauge kinetic functions, so that our results can also be applied to anomalous theories that involve the Green-Schwarz mechanism. We illustrate our two loop results by considering a few simple models: the (non-)renormalizable Wess-Zumino model and Super Quantum Electrodynamics.
Functional renormalisation group equations for supersymmetric field theories
Synatschke-Czerwonka, Franziska
2011-01-11
This work is organised as follows: In chapter 2 the basic facts of quantum field theory are collected and the functional renormalisation group equations are derived. Chapter 3 gives a short introduction to the main concepts of supersymmetry that are used in the subsequent chapters. In chapter 4 the functional RG is employed for a study of supersymmetric quantum mechanics, a supersymmetric model which are studied intensively in the literature. A lot of results have previously been obtained with different methods and we compare these to the ones from the FRG. We investigate the N=1 Wess-Zumino model in two dimensions in chapter 5. This model shows spontaneous supersymmetry breaking and an interesting fixed-point structure. Chapter 6 deals with the three dimensional N=1 Wess-Zumino model. Here we discuss the zero temperature case as well as the behaviour at finite temperature. Moreover, this model shows spontaneous supersymmetry breaking, too. In chapter 7 the two-dimensional N=(2,2) Wess-Zumino model is investigated. For the superpotential a non-renormalisation theorem holds and thus guarantees that the model is finite. This allows for a direct comparison with results from lattice simulations. (orig.)
Effective field theory for hydrodynamics: Wess-Zumino term and anomalies in two spacetime dimensions
Dubovsky, Sergei; Nicolis, Alberto
2011-01-01
We develop the formalism that incorporates quantum anomalies in the effective field theory of non-dissipative fluids. We consider the effect of adding a Wess-Zumino-like term to the low-energy effective action to account for anomalies. In this paper we restrict to two spacetime dimensions. We find modifications to the constitutive relations for the current and the stress-energy tensor, and, more interestingly, half a new propagating mode (one-and-a-halfth sound): a left- or right-moving wave with propagation speed that goes to zero with the anomaly coefficient. Unlike for the chiral magnetic wave in four dimensions, this mode propagates even in the absence of external fields. We check our results against a more standard, purely hydrodynamical derivation. Unitarity of the effective field theory suggests an upper bound on the anomaly coefficient in hydrodynamics.
Implications of Lorentz symmetry violation on a 5D supersymmetric model
García-Aguilar, J. D.; Pérez-Lorenzana, A.
2017-04-01
Field models with n extra spatial dimensions have a larger SO(1, 3 + n) Lorentz symmetry which is broken down to the standard SO(1, 3) four-dimensional one by the compactification process. By considering Lorentz violating operators in a 5D supersymmetric Wess-Zumino model, which otherwise conserve the standard four-dimensional Poincaré invariance, we show that supersymmetry (SUSY) can be restored upon a simple deformation of the supersymmetric transformations. However, SUSY is not preserved in the effective 4D theory that arises after compactification when the 5D Lorentz violating operators do not preserve Z2 : y →-y bulk parity. Our mechanism unveils a possible connection among Lorentz violation and the Scherk-Schwarz mechanism. We also show that parity preserving models, on the other hand, do provide well defined supersymmetric KK models.
Implications of Lorentz symmetry violation on a 5D supersymmetric model
García-Aguilar, J D
2016-01-01
Field models with $n$ extra spatial dimensions have a larger $SO(1,3+n)$ Lorentz symmetry which is broken down to the standard $SO(1,3)$ four dimensional symmetry by the compactification process. By considering all Lorentz violating operators in a $5D$ supersymmetric Wess-Zumino mo\\-del, which otherwise conserve standard Poincare invariance in four dimensions, we show that Supersymmetry can be restored upon a simple deformation of the supersymmetric transformations. However, Supersymmetry shall not be preserved in the effective $4D$ theory that arises after compactification when the $5D$ Lorentz violating operators do not preserve $Z_2: y\\rightarrow -y$ bulk parity. We also show that parity preserving models, on the other hand, do provide well defined supersymmetric KK models.
Chern-Simons, Wess-Zumino and other cocycles from Kashiwara-Vergne and associators
Alekseev, Anton; Naef, Florian; Xu, Xiaomeng; Zhu, Chenchang
2017-09-01
Descent equations play an important role in the theory of characteristic classes and find applications in theoretical physics, e.g., in the Chern-Simons field theory and in the theory of anomalies. The second Chern class (the first Pontrjagin class) is defined as p= where F is the curvature 2-form and is an invariant scalar product on the corresponding Lie algebra g. The descent for p gives rise to an element ω =ω _3+ω _2+ω _1+ω _0 of mixed degree. The 3-form part ω _3 is the Chern-Simons form. The 2-form part ω _2 is known as the Wess-Zumino action in physics. The 1-form component ω _1 is related to the canonical central extension of the loop group LG. In this paper, we give a new interpretation of the low degree components ω _1 and ω _0 . Our main tool is the universal differential calculus on free Lie algebras due to Kontsevich. We establish a correspondence between solutions of the first Kashiwara-Vergne equation in Lie theory and universal solutions of the descent equation for the second Chern class p. In more detail, we define a 1-cocycle C which maps automorphisms of the free Lie algebra to one forms. A solution of the Kashiwara-Vergne equation F is mapped to ω _1=C(F) . Furthermore, the component ω _0 is related to the associator Φ corresponding to F. It is surprising that while F and Φ satisfy the highly nonlinear twist and pentagon equations, the elements ω _1 and ω _0 solve the linear descent equation.
Doped Heisenberg chains: Spin-S generalizations of the supersymmetric t-J model
Frahm, Holger E-mail: frahm@itp.uni-hannover.de
1999-10-25
A family of exactly solvable models describing a spin S Heisenberg chain doped with mobile spin-(S - ((1)/(2))) carriers is constructed from gl(2|1)-invariant solutions of the Yang-Baxter equation. The models are generalizations of the supersymmetric t-J model which is obtained for S ((1)/(2)). We solve the model by means of the algebraic Bethe Ansatz and present results for the zero temperature and thermodynamic properties. At low temperatures the models show spin charge separation, i.e. contain contributions of a free bosonic theory in the charge sector and an SU(2)-invariant theory describing the magnetic excitations. For small carrier concentration the latter can be decomposed further into an SU(2) level-2S Wess-Zumino-Novikov-Witten model and the minimal unitary model M{sub p} with p 2S + 1.
Monaco, Domenico
2016-01-01
We establish a connection between two recently-proposed approaches to the understanding of the geometric origin of the Fu-Kane-Mele invariant $\\mathrm{FKM} \\in \\mathbb{Z}_2$, arising in the context of 2-dimensional time-reversal symmetric topological insulators. On the one hand, the $\\mathbb{Z}_2$ invariant can be formulated in terms of the Berry connection and the Berry curvature of the Bloch bundle of occupied states over the Brillouin torus. On the other, using techniques from the theory of bundle gerbes it is possible to provide an expression for $\\mathrm{FKM}$ containing the square root of the Wess-Zumino amplitude for a certain $U(N)$-valued field over the Brillouin torus. We link the two formulas by showing directly the equality between the above mentioned Wess-Zumino amplitude and the Berry phase, as well as between their square roots. An essential tool of independent interest is an equivariant version of the adjoint Polyakov-Wiegmann formula for fields $\\mathbb{T}^2 \\to U(N)$, of which we provide a p...
Monaco, Domenico; Tauber, Clément
2017-02-01
We establish a connection between two recently proposed approaches to the understanding of the geometric origin of the Fu-Kane-Mele invariant FKMin Z_2 , arising in the context of two-dimensional time-reversal symmetric topological insulators. On the one hand, the Z_2 invariant can be formulated in terms of the Berry connection and the Berry curvature of the Bloch bundle of occupied states over the Brillouin torus. On the other, using techniques from the theory of bundle gerbes, it is possible to provide an expression for FKM containing the square root of the Wess-Zumino amplitude for a certain U(N)-valued field over the Brillouin torus. We link the two formulas by showing directly the equality between the above-mentioned Wess-Zumino amplitude and the Berry phase, as well as between their square roots. An essential tool of independent interest is an equivariant version of the adjoint Polyakov-Wiegmann formula for fields T^2 → U(N) , of which we provide a proof employing only basic homotopy theory and circumventing the language of bundle gerbes.
The Dilaton Wess-Zumino Action in 6 Dimension from Weyl Gauging: Local Anomalies and Trace Relations
Coriano, Claudio; Marzo, Carlo; Serino, Mirko
2013-01-01
We extend a previous analysis on the derivation of the dilaton Wess-Zumino (WZ) action in $d=4$, based on the method of Weyl gauging, to $6$ dimensions. As in the previous case, we discuss the structure of the same action in dimensional regularization using 6-dimensional Weyl invariants, extracting the dilaton interactions in the most general scheme, with the inclusion of the local anomaly terms. As an application, we present the WZ action for the (2,0) tensor multiplet, which has been investigated in the past in the context of the $AdS_7/CFT_6$ holographic anomaly matching. We then extend to $d=6$ the investigation of fully traced correlation functions of EMT's, formerly presented in $d=4$, showing that their hierarchy is functionally related only to the first 6 correlators. We give the explicit expressions of these in the most general scheme, up to rank-4.
Domain Wall Junction in N=2 Supersymmetric QED in four dimensions
Kakimoto, K; Kakimoto, Kazuya; Sakai, Norisuke
2003-01-01
An exact solution of domain wall junction is obtained in N=2 supersymmetric (SUSY) QED with three massive hypermultiplets. The junction preserves two out of eight SUSY. Both a (magnetic) Fayet-Iliopoulos (FI) term and complex masses for hypermultiplets are needed to obtain the junction solution. There are zero modes corresponding to spontaneously broken translation, SUSY, and U(1). All broken and unbroken SUSY charges are explicitly worked out in the Wess-Zumino gauge in N=1 superfields as well as in components. The relation to models in five dimensions is also clarified.
Introduction to Supersymmetric Gauge Theories
Piguet, O
1997-01-01
In these lectures I present a basic introduction to supersymmetry, especially to N=1 supersymmetric gauge theories and their renormalization, in the Wess-Zumino gauge. I also discuss the various ways supersymmetry may be broken in order to account for the lack of exact supersymmetry in the actual world of elementary particles.
Chiral anomalies in N=1 supersymmetric Yang-Mills theories
Girardi, G.; Grimm, R.; Stora, R. (Grenoble-1 Univ., 74 - Annecy (France). Lab. de Physique des Particules)
1985-06-20
We establish a manifestly supersymmetric, compact, formula for the chiral anomalies of supersymmetric gauge theories. This result is obtained by combining superspace geometry with the usual algebra of anomalies. Except for a Wess-Zumino type term, we obtain an expression which is polynomial in the coefficients of the superconnection form.
Effective action for supersymmetric chiral anomaly
Krivoshchekov, V.K.; Chekhov, L.O.
1987-05-01
It is shown that consistency conditions of the type of the Wess-Zumino conditions are necessary and sufficient conditions for local integrability of the supersymmetric chiral anomaly. It follows from the requirement of global integrability that the coefficient of the anomalous action is discrete. Explicit expressions are obtained for consistent anomalies and the corresponding functionals, which depend on superfields of various types.
A renormalization in group study of supersymmetric field theories
Heilmann, Marianne
2015-05-13
This thesis analyses scalar supersymmetric field theories within the framework of the functional renormalization group (FRG). Classical physics on microscopic scales is connected to the effective model on macroscopic scales via the scale-dependent effective average action by a reformulation of the path integral. Three supersymmetric theories are explored in detail: supersymmetric quantum mechanics, the three-dimensional Wess-Zumino model and supersymmetric spherical theories in three dimensions. The corresponding renormalization group flow is formulated in a manifestly supersymmetric way. By utilizing an expansion of the effective average action in derivative operators, an adequate and intrinsically non-perturbative truncation scheme is selected. In quantum mechanics, the supersymmetric derivative expansion is shown to converge by increasing the order of truncation. Besides, high-accuracy results for the ground and first excited state energies for quantum systems with conserved as well as spontaneously broken supersymmetry are achieved. Furthermore, the critical behaviour of the three-dimensional Wess-Zumino is investigated. Via spectral methods, a global Wilson-Fisher scaling solution and its corresponding universal exponents are determined. Besides, a superscaling relation of the leading exponents is verified for arbitrary dimensions greater than or equal to two. Lastly, three-dimensional spherical, supersymmetric theories are analysed. Their phase structure is determined in detail for infinite as well as finitely many superfields. The exact one-parameter scaling solution for infinitely many fields is shown to collapse to a single non-trivial Wilson-Fisher fixed-point for finitely many superfields. It is pointed out that the strongly-coupled domains of these theories are plagued by Landau poles and non-analyticities, indicating spontaneous supersymmetry breaking.
Krivoshchekov, V.L.; Slavnov, A.A.; Chekhov, L.O.
1988-01-01
An effective meson action is constructed for supersymmetric quantum chromodynamics (SUSY-QCD) in the framework of the 1/N expansion. It is shown that there is no dynamical spontaneous breaking of the supersymmetry. The explicit expression obtained for the low-energy action with allowance for the anomaly is the supersymmetric generalization of the Weinberg-Wess-Zumino-Witten action.
Phases of supersymmetric O(N) theories
Heilmann, Marianne; Synatschke-Czerwonka, Franziska; Wipf, Andreas
2012-01-01
We perform a global renormalization group study of O(N) symmetric Wess-Zumino theories and their phases in three euclidean dimensions. At infinite N the theory is solved exactly. The phases and phase transitions are worked out for finite and infinite short-distance cutoffs. A distinctive new feature arises at strong coupling, where the effective superfield potential becomes multi-valued, signalled by divergences in the fermion-boson interaction. Our findings resolve the long-standing puzzle about the occurrence of degenerate O(N) symmetric phases. At finite N, we find a strongly-coupled fixed point in the local potential approximation and explain its impact on the phase transition. We also examine the possibility for a supersymmetric Bardeen-Moshe-Bander phenomenon, and relate our findings with the spontaneous breaking of supersymmetry in other models.
D-foam-induced flavor condensates and breaking of supersymmetry in free Wess-Zumino fluids
Mavromatos, N E; Tarantino, W
2011-01-01
Recently {[}N. E. Mavromatos and S. Sarkar, New J. Phys. 10, 073009 (2008); N. E. Mavromatos, S. Sarkar, and W. Tarantino, Phys. Rev. D 80, 084046 (2009)], we argued that a particular model of string-inspired quantum space-time foam (D-foam) may induce oscillations and mixing among flavored particles. As a result, rather than the mass-eigenstate vacuum, the correct ground state to describe the underlying dynamics is the flavor vacuum, proposed some time ago by Blasone and Vitiello as a description of quantum field theories with mixing. At the microscopic level, the breaking of target-space supersymmetry is induced in our space-time foam model by the relative transverse motion of brane defects. Motivated by these results, we show that the flavor vacuum, introduced through an inequivalent representation of the canonical (anti-) commutation relations, provides a vehicle for the breaking of supersymmetry at a low-energy effective field-theory level; on considering the flavor-vacuum expectation value of the energy...
Gauged spinning models with deformed supersymmetry
Fedoruk, Sergey
2016-01-01
New models of the SU(2|1) supersymmetric mechanics based on gauging the systems with dynamical (1,4,3) and semi-dynamical (4,4,0) supermultiplets are presented. We propose a new version of SU(2|1) harmonic superspace approach which makes it possible to construct the Wess-Zumino term for interacting (4,4,0) multiplets. A new N=4 extension of d=1 Calogero-Moser multiparticle system is obtained by gauging the U(n) isometry of matrix SU(2|1) harmonic superfield model.
Supersymmetry breaking and gauge mediation in models with a generic superpotential
Kitano, Ryuichiro [Los Alamos National Laboratory; Ookouchi, Yutaka [CANADA
2008-01-01
In this note, we present a transparent scheme for finding or creating a (meta)stable vacuum in general supersymmetric models. We derive general conditions for having a supersymmetry breaking vacuum by connecting different models by a coordinate transformation, which is an application of the method used in [16]. In particular, we find that there can be a metastable supersymmetry breaking vacuum in models with the canonical Kahler potential and a generic superpotential. For example, the Wess-Zumino model coupled to the messenger fields possesses a metastable vacuum if coefficients of the superpotential terms satisfy certain inequalities.
On the one-loop effective potential in nonlocal supersymmetric theories
de Mello, E R Bezerra; Nascimento, J R; Petrov, A Yu
2016-01-01
Within the superfield approach, we consider the nonlocal generalization of the Wess-Zumino model and calculate the one-loop low-energy contributions to the effective action. Four different nonlocal models are considered, among which only the first model does not reduce to the standard Wess-Zumino model when we take the parameter of nonlocality of the model, $\\Lambda$, much greater than any energy scale; in addition, this model also depends on an extra parameter, $\\xi$. As to the other three models, the result looks like the renormalized effective potential for the usual Wess-Zumino model, where the normalization scale $\\mu$ is replaced by the $\\Lambda$. Moreover, the fourth model displays a divergence which can be eliminated through the appropriate wave function renormalization.
Supersymmetric structure of the induced $W$ gravities
Ader, J P; Noirot, Y; Ader, Jean-Pierre; Biet, Franck; Noirot, Yves
1999-01-01
We derive the supersymmetric structure present in W-gravities which has been already observed in various contexts as Yang-Mills theory, topological field theories, bosonic string and chiral W_{3}-gravity. This derivation which is made in the geometrical framework of Zucchini, necessitates the introduction of an appropriate new basis of variables which replace the canonical fields and their derivatives. This construction is used, in the W_{2}-case, to deduce from the Chern-Simons action the Wess-Zumino-Polyakov action.
Bagger, J.A.
1984-09-01
We begin to construct the most general supersymmetric Lagrangians in one, two and four dimensions. We find that the matter couplings have a natural interpretation in the language of the nonlinear sigma model.
Gudnason, Sven Bjarke; Sasaki, Shin
2015-01-01
Construction of a supersymmetric extension of the Skyrme term was a long-standing problem because of the auxiliary field problem; that is, the auxiliary field may propagate and cannot be eliminated, and the problem of having fourth-order time derivative terms. In this paper, we construct for the first time a supersymmetric extension of the Skyrme term in four spacetime dimensions, in the manifestly supersymmetric superfield formalism that does not suffer from the auxiliary field problem. Chiral symmetry breaking in supersymmetric theories results not only in Nambu-Goldstone (NG) bosons (pions) but also in the same number of quasi-NG bosons so that the low-energy theory is described by an SL(N,C)-valued matrix field instead of SU(N) for NG bosons. The solution of auxiliary fields is trivial on the canonical branch of the auxiliary field equation, in which case our model results in a fourth-order derivative term that is not the Skyrme term. For the case of SL(2,C), we find explicitly a nontrivial solution to th...
Application of the Faddeev-Jackiw formalism to the gauged WZW model
Paschalis, J E; Paschalis, J E; Porfyriadis, P I
1995-01-01
The two-flavor Wess-Zumino model coupled to electromagnetism is treated as a constraint system using the Faddeev-Jackiw method. Expanding into series of powers of the pion fields and keeping terms up to second and third order we obtain Coulomb- gauge Lagrangeans containing non-local terms.
Hamiltonian reduction of the U$_{EM}$(1) gauged three flavour WZW model
Paschalis, J E
1995-01-01
The three-flavour Wess-Zumino model coupled to electromagnetism is treated as a constraint system using the Faddeev-Jackiw method. Expanding into series of powers of the Goldstone boson fields and keeping terms up to second and third order we obtain Coulomb-gauge hamiltonian densities.
Fu, Wenbo; Maldacena, Juan; Sachdev, Subir
2016-01-01
We discuss a supersymmetric generalization of the Sachdev-Ye-Kitaev model. These are quantum mechanical models involving $N$ Majorana fermions. The supercharge is given by a polynomial expression in terms of the Majorana fermions with random coefficients. The Hamiltonian is the square of the supercharge. The ${\\cal N}=1$ model with a single supercharge has unbroken supersymmetry at large $N$, but non-perturbatively spontaneously broken supersymmetry in the exact theory. We analyze the model by looking at the large $N$ equation, and also by performing numerical computations for small values of $N$. We also compute the large $N$ spectrum of "singlet" operators, where we find a structure qualitatively similar to the ordinary SYK model. We also discuss an ${\\cal N}=2$ version. In this case, the model preserves supersymmetry in the exact theory and we can compute a suitably weighted Witten index to count the number of ground states, which agrees with the large $N$ computation of the entropy. In both cases, we disc...
The Supersymmetric Standard Model
Fayet, Pierre
2016-10-01
The Standard Model may be included within a supersymmetric theory, postulating new sparticles that differ by half-a-unit of spin from their standard model partners, and by a new quantum number called R-parity. The lightest one, usually a neutralino, is expected to be stable and a possible candidate for dark matter. The electroweak breaking requires two doublets, leading to several charged and neutral Brout-Englert-Higgs bosons. This also leads to gauge/Higgs unification by providing extra spin-0 partners for the spin-1 W± and Z. It offers the possibility to view, up to a mixing angle, the new 125 GeV boson as the spin-0 partner of the Z under two supersymmetry transformations, i.e. as a Z that would be deprived of its spin. Supersymmetry then relates two existing particles of different spins, in spite of their different gauge symmetry properties, through supersymmetry transformations acting on physical fields in a non-polynomial way. We also discuss how the compactification of extra dimensions, relying on R-parity and other discrete symmetries, may determine both the supersymmetrybreaking and grand-unification scales.
The Supersymmetric Standard Model
Fayet, Pierre
2016-01-01
The Standard Model may be included within a supersymmetric theory, postulating new sparticles that differ by half-a-unit of spin from their standard model partners, and by a new quantum number called R-parity. The lightest one, usually a neutralino, is expected to be stable and a possible candidate for dark matter. The electroweak breaking requires two doublets, leading to several charged and neutral Brout- Englert-Higgs bosons. This also leads to gauge/Higgs unification by providing extra spin-0 partners for the spin-1 W$^\\pm$ and Z. It offers the possibility to view, up to a mixing angle, the new 125 GeV boson as the spin-0 partner of the Z under two supersymmetry transformations, i.e. as a Z that would be deprived of its spin. Supersymmetry then relates two existing particles of different spins, in spite of their different gauge symmetry properties, through supersymmetry transformations acting on physical fields in a non-polynomial way. We also discuss how the compactification of extra dimensions, relying ...
The Roots of the Standard Model of Particle Physics
Mulders, P J
2016-01-01
We conjecture how the particle content of the standard model can emerge starting with a supersymmetric Wess-Zumino model in 1+1 dimensions (d = 2) with three real boson and fermion fields. Considering SU(3) transformations, the lagrangian and its ground state are SO(3) invariant. The SO(3) symmetry extends the basic IO(1,1) Poincar\\'e symmetry to IO(1,3) for the asymptotic fields requiring physical states to be singlets under the A_4 symmetry that governs the SO(3) embedding. This is linked to the three-family structure. For the internal symmetries of the asymptotic fields an SU(2) x U(1) symmetry remains, broken down as in the standard model. The boson excitations in d = 4 are identified with electroweak gauge bosons and the Higgs boson. Fermion excitations come in three families of leptons living in E(1,3) Minkowski space or three families of quarks living in E(1,1). Many features of the standard model now emerge in a natural way. The supersymmetric starting point solves the naturalness problem. The underly...
n = 4 supersymmetric FRW model
Rosales, J.J.; Pashnev, A. [Bogoliubov Laboratory of Theoretical Physics, JINR, Dubna, 141980 (Russian Federation); Tkach, V.I. [Instituto de Fisica, Universidad de Guanajuato, 05315-970 Leon, 66318 Guanajuato (Mexico)]. e-mail: juan@ifug3.ugto.mx, pashnev@thsun1.jinr.ru, vladimir@ifug3.ugto.mx
2003-07-01
In this work we have constructed the n = 4 extended local conformal time supersymmetry for the Friedmann-Robertson-Walker cosmological models. This is based on the superfield construction of the action, which is invariant under world line local n = 4 supersymmetry with SU(2){sub local} X SU(2){sub global} internal subgroup. It is shown that the supersymmetric action has the form of the localized (or superconformal) version of the action for n = 4 supersymmetric quantum mechanics. This superfield procedure provides a well defined scheme for including super matter. (Author)
Gauged Sigma Models from 2 + 1 Dimensions and the Issue of Unitarity
Abouelsaood, A.; Pope, C. N.; Sezgin, E.; Shen, X.
As a Lagrangian realization of the Goddard-Kent-Olive G/H coset construction, Castellani, D'Auria and Levi recently proposed a gauged Wess-Zumino-Witten model in which the topological term is a difference of Chern-Simons forms. We show that their Lagrangian is actually an ungauged Wess-Zumino-Witten model plus a gauge field coupled linearly to an H-current, thus describing non-abelian chiral bosons with a linear constraint. We carry out the Dirac quantization procedure and show that the Hamiltonian is of the current-current form with indefinite signature, thus signaling instability. We also clarify the relationship of this model with that of Moore and Seiberg, which does provide an anomaly-free formulation of the GKO coset construction.
The gauging of two-dimensional bosonic sigma models on world-sheets with defects
Gawedzki, Krzysztof; Waldorf, Konrad
2013-01-01
We extend our analysis of the gauging of rigid symmetries in bosonic two-dimensional sigma models with Wess-Zumino terms in the action to the case of world-sheets with defects. A structure that permits a non-anomalous coupling of such sigma models to world-sheet gauge fields of arbitrary topology is analysed, together with obstructions to its existence, and the classification of its inequivalent choices.
Integrable modification of the critical Chalker-Coddington network model
Ikhlef, Yacine; Fendley, Paul; Cardy, John
2011-10-01
We consider the Chalker-Coddington network model for the integer quantum Hall effect, and examine the possibility of solving it exactly. In the supersymmetric path integral framework, we introduce a truncation procedure, leading to a series of well-defined two-dimensional loop models with two loop flavors. In the phase diagram of the first-order truncated model, we identify four integrable branches related to the dilute Birman-Wenzl-Murakami braid-monoid algebra and parameterized by the loop fugacity n. In the continuum limit, two of these branches (1,2) are described by a pair of decoupled copies of a Coulomb-gas theory, whereas the other two branches (3,4) couple the two loop flavors, and relate to an SU(2)r×SU(2)r/SU(2)2r Wess-Zumino-Witten (WZW) coset model for the particular values n=-2cos[π/(r+2)], where r is a positive integer. The truncated Chalker-Coddington model is the n=0 point of branch 4. By numerical diagonalization, we find that its universality class is neither an analytic continuation of the WZW coset nor the universality class of the original Chalker-Coddington model. It constitutes rather an integrable, critical approximation to the latter.
Supersymmetric Sigma Model Geometry
Ulf Lindström
2012-01-01
This is a review of how sigma models formulated in Superspace have become important tools for understanding geometry. Topics included are: The (hyper)k\\"ahler reduction; projective superspace; the generalized Legendre construction; generalized K\\"ahler geometry and constructions of hyperk\\"ahler metrics on Hermitean symmetric spaces.
Supersymmetric Sigma Model geometry
Lindström, Ulf
2012-01-01
This is a review of how sigma models formulated in Superspace have become important tools for understanding geometry. Topics included are: The (hyper)k\\"ahler reduction; projective superspace; the generalized Legendre construction; generalized K\\"ahler geometry and constructions of hyperk\\"ahler metrics on Hermitean symmetric spaces.
Electroweak breaking in supersymmetric models
Ibáñez, L E
1992-01-01
We discuss the mechanism for electroweak symmetry breaking in supersymmetric versions of the standard model. After briefly reviewing the possible sources of supersymmetry breaking, we show how the required pattern of symmetry breaking can automatically result from the structure of quantum corrections in the theory. We demonstrate that this radiative breaking mechanism works well for a heavy top quark and can be combined in unified versions of the theory with excellent predictions for the running couplings of the model. (To be published in ``Perspectives in Higgs Physics'', G. Kane editor.)
A Maximally Supersymmetric Kondo Model
Harrison, Sarah; Kachru, Shamit; Torroba, Gonzalo; /Stanford U., Phys. Dept. /SLAC
2012-02-17
We study the maximally supersymmetric Kondo model obtained by adding a fermionic impurity to N = 4 supersymmetric Yang-Mills theory. While the original Kondo problem describes a defect interacting with a free Fermi liquid of itinerant electrons, here the ambient theory is an interacting CFT, and this introduces qualitatively new features into the system. The model arises in string theory by considering the intersection of a stack of M D5-branes with a stack of N D3-branes, at a point in the D3 worldvolume. We analyze the theory holographically, and propose a dictionary between the Kondo problem and antisymmetric Wilson loops in N = 4 SYM. We perform an explicit calculation of the D5 fluctuations in the D3 geometry and determine the spectrum of defect operators. This establishes the stability of the Kondo fixed point together with its basic thermodynamic properties. Known supergravity solutions for Wilson loops allow us to go beyond the probe approximation: the D5s disappear and are replaced by three-form flux piercing a new topologically non-trivial S3 in the corrected geometry. This describes the Kondo model in terms of a geometric transition. A dual matrix model reflects the basic properties of the corrected gravity solution in its eigenvalue distribution.
A note on colored HOMFLY polynomials for hyperbolic knots from WZW models
Gu, Jie
2014-01-01
Using the correspondence between Chern-Simons theories and Wess-Zumino-Witten models we present the necessary tools to calculate colored HOMFLY polynomials for hyperbolic knots. For two-bridged hyperbolic knots we derive the colored HOMFLY invariants in terms of crossing matrices of the underlying Wess-Zumino-Witten model. Our analysis extends previous works by incorporating non-trivial multiplicities for the primaries appearing in the crossing matrices, so as to describe colorings of HOMFLY invariants beyond the totally symmetric or anti-symmetric representations of SU(N). The crossing matrices directly relate to 6j-symbols of the quantum group U_q(su(N)). We present powerful methods to calculate such quantum 6j-symbols for general N. This allows us to explicitly determine previously unknown colored HOMFLY polynomials for all two-bridged hyperbolic knots. Yet, the scope of application of our techniques goes beyond knot theory; e.g., our findings can be used to study correlators in Wess-Zumino-Witten conforma...
Patterns of flavor signals in supersymmetric models
Goto, T. [KEK National High Energy Physics, Tsukuba (Japan)]|[Kyoto Univ. (Japan). YITP; Okada, Y. [KEK National High Energy Physics, Tsukuba (Japan)]|[Graduate Univ. for Advanced Studies, Tsukuba (Japan). Dept. of Particle and Nucelar Physics; Shindou, T. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[International School for Advanced Studies, Trieste (Italy); Tanaka, M. [Osaka Univ., Toyonaka (Japan). Dept. of Physics
2007-11-15
Quark and lepton flavor signals are studied in four supersymmetric models, namely the minimal supergravity model, the minimal supersymmetric standard model with right-handed neutrinos, SU(5) supersymmetric grand unified theory with right-handed neutrinos and the minimal supersymmetric standard model with U(2) flavor symmetry. We calculate b{yields}s(d) transition observables in B{sub d} and B{sub s} decays, taking the constraint from the B{sub s}- anti B{sub s} mixing recently observed at Tevatron into account. We also calculate lepton flavor violating processes {mu} {yields} e{gamma}, {tau} {yields} {mu}{gamma} and {tau} {yields} e{gamma} for the models with right-handed neutrinos. We investigate possibilities to distinguish the flavor structure of the supersymmetry breaking sector with use of patterns of various flavor signals which are expected to be measured in experiments such as MEG, LHCb and a future Super B Factory. (orig.)
The Minimal Supersymmetric Fat Higgs Model
Harnik, R; Larson, D T; Murayama, H; Harnik, Roni; Kribs, Graham D.; Larson, Daniel T.; Murayama, Hitoshi
2003-01-01
We present a calculable supersymmetric theory of a composite ``fat'' Higgs boson. Electroweak symmetry is broken dynamically through a new gauge interaction that becomes strong at an intermediate scale. The Higgs mass can easily be 200-450 GeV along with the superpartner masses, solving the supersymmetric little hierarchy problem. We explicitly verify that the model is consistent with precision electroweak data without fine-tuning. Gauge coupling unification can be maintained despite the inherently strong dynamics involved in electroweak symmetry breaking. Supersymmetrizing the Standard Model therefore does not imply a light Higgs mass, contrary to the lore in the literature. The Higgs sector of the minimal Fat Higgs model has a mass spectrum that is distinctly different from the Minimal Supersymmetric Standard Model.
Generalized Kahler Geometry from supersymmetric sigma models
Bredthauer, A; Persson, J; Zabzine, M; Bredthauer, Andreas; Lindstrom, Ulf; Persson, Jonas; Zabzine, Maxim
2006-01-01
We give a physical derivation of generalized Kahler geometry. Starting from a supersymmetric nonlinear sigma model, we rederive and explain the results of Gualtieri regarding the equivalence between generalized Kahler geometry and the bi-hermitean geometry of Gates-Hull-Rocek. When cast in the language of supersymmetric sigma models, this relation maps precisely to that between the Lagrangian and the Hamiltonian formalisms. We also discuss topological twist in this context.
Two Loop Effective Kähler Potential
Nyawelo, T S; Nyawelo, Tino S.; Nibbelink, Stefan Groot
2007-01-01
In this talk we study the renormalization of the effective Kaehler potential at one and two loops for general four dimensional (non--renormalizable) N=1 supersymmetric theories described by arbitrary Kaehler potential, superpotential and gauge kinetic function. We consider the Wess-Zumino model as an example.
Spectral properties in supersymmetric matrix models
Boulton, Lyonell, E-mail: L.Boulton@hw.ac.uk [Department of Mathematics and Maxwell Institute for Mathematical Sciences, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Garcia del Moral, Maria Pilar, E-mail: garciamormaria@uniovi.es [Departamento de Fisica, Universidad de Oviedo, Avda Calvo Sotelo 18, 33007 Oviedo (Spain); Restuccia, Alvaro, E-mail: arestu@usb.ve [Departamento de Fisica, Universidad Simon Bolivar, Apartado 89000, Caracas (Venezuela, Bolivarian Republic of); Departamento de Fisica, Universidad de Oviedo, Avda Calvo Sotelo 18, 33007 Oviedo (Spain)
2012-03-21
We formulate a general sufficiency criterion for discreteness of the spectrum of both supersymmmetric and non-supersymmetric theories with a fermionic contribution. This criterion allows an analysis of Hamiltonians in complete form rather than just their semiclassical limits. In such a framework we examine spectral properties of various (1+0) matrix models. We consider the BMN model of M-theory compactified on a maximally supersymmetric pp-wave background, different regularizations of the supermembrane with central charges and a non-supersymmetric model comprising a bound state of N D2 with m D0. While the first two examples have a purely discrete spectrum, the latter has a continuous spectrum with a lower end given in terms of the monopole charge.
Supersymmetric defect models and mirror symmetry
Hook, Anson; Kachru, Shamit; Torroba, Gonzalo
2013-11-01
We study supersymmetric field theories in three space-time dimensions doped by various configurations of electric charges or magnetic fluxes. These are supersymmetric avatars of impurity models. In the presence of additional sources such configurations are shown to preserve half of the supersymmetries. Mirror symmetry relates the two sets of configurations. We discuss the implications for impurity models in 3d NN = 4 QED with a single charged hypermultiplet (and its mirror, the theory of a free hypermultiplet) as well as 3d NN = 2 QED with one flavor and its dual, a supersymmetric Wilson-Fisher fixed point. Mirror symmetry allows us to find backreacted solutions for arbitrary arrays of defects in the IR limit of NN = 4 QED. Our analysis, complemented with appropriate string theory brane constructions, sheds light on various aspects of mirror symmetry, the map between particles and vortices and the emergence of ground state entropy in QED at finite density.
Supersymmetric Defect Models and Mirror Symmetry
Hook, Anson; Torroba, Gonzalo
2013-01-01
We study supersymmetric field theories in three space-time dimensions doped by various configurations of electric charges or magnetic fluxes. These are supersymmetric avatars of impurity models. In the presence of additional sources such configurations are shown to preserve half of the supersymmetries. Mirror symmetry relates the two sets of configurations. We discuss the implications for impurity models in 3d N=4 QED with a single charged hypermultiplet (and its mirror, the theory of a free hypermultiplet) as well as 3d N=2 QED with one flavor and its dual, a supersymmetric Wilson-Fisher fixed point. Mirror symmetry allows us to find backreacted solutions for arbitrary arrays of defects in the IR limit of N=4 QED. Our analysis, complemented with appropriate string theory brane constructions, sheds light on various aspects of mirror symmetry, the map between particles and vortices and the emergence of ground state entropy in QED at finite density.
Just so oscillations in supersymmetric standard model
Joshipura, A S; Anjan S Joshipura; Marek Nowakowski
1995-01-01
We analyze the spectrum and mixing among neutrinos in the minimal supersymmetric standard model with explicit breaking of R parity. It is shown that ({\\em i}) the mixing among neutrinos is naturally large and ({\\em ii}) the non zero neutrino mass is constrained to be \\leq 10^{-5} eV from arguments based on baryogenesis. Thus vacuum oscillations of neutrinos in this model may offer a solution of the solar neutrino problem. The allowed space of the supersymmetric parameters consistent with this solution is determined.
A renormalizable supersymmetric SO(10) model
Chen, Ying-Kang
2015-01-01
A realistic grand unified model has never been constructed in the literature due to three major difficulties: the seesaw mechanism without spoiling gauge coupling unification, the doublet-triplet splitting and the proton decay suppression. We propose a renormalizable supersymmetric SO(10) model with all these difficulties solved naturally.
A simple model of direct gauge mediation
Zheng Sibo, E-mail: sibozheng.zju@gmail.com [Department of Physics, Chongqing University, Chongqing 401331 (China); Yu Yao [Department of Physics, Chongqing University, Chongqing 401331 (China)
2012-03-23
In the context of direct gauge mediation Wess-Zumino models are very attractive in supersymmetry model building. Besides the spontaneous supersymmetry and R-symmetry breaking, the problems of small gaugino mass as well as {mu} and B{mu} terms should be solved so as to achieve a viable model. In this Letter, we propose a simple model as an existence proof, in which all these subjects are realized simultaneously, with no need of fine tuning. This completion also implies that much of parameter space for direct gauge mediation can be directly explored at LHC.
A constrained supersymmetric left-right model
Hirsch, Martin; Opferkuch, Toby; Porod, Werner; Staub, Florian
2016-01-01
We present a supersymmetric left-right model which predicts gauge coupling unification close to the string scale and extra vector bosons at the TeV scale. The subtleties in constructing a model which is in agreement with the measured quark masses and mixing for such a low left-right breaking scale are discussed. It is shown that in the constrained version of this model radiative breaking of the gauge symmetries is possible and a SM-like Higgs is obtained. Additional CP-even scalars of a similar mass or even much lighter are possible. The expected mass hierarchies for the supersymmetric states differ clearly from those of the constrained MSSM. In particular, the lightest down-type squark, which is a mixture of the sbottom and extra vector-like states, is always lighter than the stop. We also comment on the model's capability to explain current anomalies observed at the LHC.
Utilitarian Supersymmetric Gauge Model of Particle Interactions
Ma, Ernest
2010-01-01
A remarkable U(1) gauge extension of the supersymmetric standard model was proposed eight years ago. It is anomaly-free, has no mu term, and conserves baryon and lepton numbers automatically. The phenomenology of a specific version of this model is discussed. In particular, leptoquarks are predicted, with couplings to the heavy singlet neutrinos, the scalar partners of which may be components of dark matter. The Majorana neutrino mass matrix itself may have two zero subdeterminants.
Flavor Mixing Phenomenology in Supersymmetric Models
Rehman, Muhammad
2016-01-01
This dissertation investigates the flavor mixing effects in supersymmetric models on electroweak precision observables, Higgs boson mass predictions, B-physics observables, quark flavor violating Higgs decays, lepton flavor violating charged lepton decays and lepton flavor violating Higgs decays. The flavor mixing effects are studied in model independent way i.e. by putting off-diagonal entries in the sfermion mass matrix by hand as well as in the minimal flavor violating constrained MSSM, where mixing can originate from CKM matrix in the case of squarks and from PMNS matrix in the case of sleptons. We found that flavor mixing can have large impact to some observables, enabling us to put new constraints on parameter space in supersymmetric models.
Signatures of the Minimal Moose Model With Exact Parity
Freitas, A.; Schwaller, P.; Wyler, D.
2010-03-01
In the popular littlest Higgs model, T-parity can be broken by Wess-Zumino-Witten (WZW) terms induced by a strongly coupled UV completion. On the other hand, certain models with multiple scalar multiplets (called moose models) permit the implementation of T-parity such that it is not broken by the WZW terms. Here we present a concrete realization of such a model, and discuss the phenomenology at the Large Hadron Collider, in particular differences with respect to the littlest Higgs model.
Phenomenology of the Utilitarian Supersymmetric Standard Model
Fraser, Sean; Ma, Ernest; Pollard, Nicholas; Popov, Oleg; Zakeri, Mohammadreza
2016-01-01
We study the 2010 specific version of the 2002 proposed $U(1)_X$ extension of the supersymmetric standard model, which has no $\\mu$ term and conserves baryon number and lepton number separately and automatically. We consider in detail the scalar sector as well as the extra $Z_X$ gauge boson, and their interactions with the necessary extra color-triplet particles of this model, which behave as leptoquarks. We show how the diphoton excess at 750 GeV, recently observed at the LHC, may be explained within this context. We identify a new fermion dark-matter candidate and discuss its properties. An important byproduct of this study is the discovery of relaxed supersymmetric constraints on the Higgs boson's mass of 125 GeV.
Phenomenology of the utilitarian supersymmetric standard model
Fraser, Sean; Kownacki, Corey; Ma, Ernest; Pollard, Nicholas; Popov, Oleg; Zakeri, Mohammadreza
2016-08-01
We study the 2010 specific version of the 2002 proposed U(1)X extension of the supersymmetric standard model, which has no μ term and conserves baryon number and lepton number separately and automatically. We consider in detail the scalar sector as well as the extra ZX gauge boson, and their interactions with the necessary extra color-triplet particles of this model, which behave as leptoquarks. We show how the diphoton excess at 750 GeV, recently observed at the LHC, may be explained within this context. We identify a new fermion dark-matter candidate and discuss its properties. An important byproduct of this study is the discovery of relaxed supersymmetric constraints on the Higgs boson's mass of 125 GeV.
Topological solitons in the supersymmetric Skyrme model
Gudnason, Sven Bjarke; Sasaki, Shin
2016-01-01
A supersymmetric extension of the Skyrme model was obtained recently, which consists of only the Skyrme term in the Nambu-Goldstone (pion) sector complemented by the same number of quasi-Nambu-Goldstone bosons. Scherk-Schwarz dimensional reduction yields a kinetic term in three or lower dimensions and a potential term in two dimensions, preserving supersymmetry. Euclidean solitons (instantons) are constructed in the supersymmetric Skyrme model. In four dimensions, the soliton is an instanton first found by Speight. Scherk-Schwarz dimensional reduction is then performed once to get a 3-dimensional theory in which a 3d Skyrmion-instanton is found and then once more to get a 2d theory in which a 2d vortex-instanton is obtained. Although the last one is a global vortex it has finite action in contrast to conventional theory. All of them are non-BPS states breaking all supersymmetries.
Non-supersymmetric Orientifolds of Gepner Models
Gato-Rivera, B
2008-01-01
Starting from a previously collected set of tachyon-free closed strings, we search for N=2 minimal model orientifold spectra which contain the standard model and are free of tachyons and tadpoles at lowest order. For each class of tachyon-free closed strings -- bulk supersymmetry, automorphism invariants or Klein bottle projection -- we do indeed find non-supersymmetric and tachyon free chiral brane configurations that contain the standard model. However, a tadpole-cancelling hidden sector could only be found in the case of bulk supersymmetry. Although about half of the examples we have found make use of branes that break the bulk space-time supersymmetry, the resulting massless open string spectra are nevertheless supersymmetric in all cases. Dropping the requirement that the standard model be contained in the spectrum, we find chiral tachyon and tadpole-free solutions in all three cases, although in the case of bulk supersymmetry all massless spectra are supersymmetric. In the other two cases we find truly ...
Approximate Flavor Symmetry in Supersymmetric Model
Tao, Zhijian
1998-01-01
We investigate the maximal approximate flavor symmetry in the framework of generic minimal supersymmetric standard model. We consider the low energy effective theory of the flavor physics with all the possible operators included. Spontaneous flavor symmetry breaking leads to the approximate flavor symmetry in Yukawa sector and the supersymmetry breaking sector. Fermion mass and mixing hierachies are the results of the hierachy of the flavor symmetry breaking. It is found that in this theory i...
Simulations of a supersymmetry inspired model on a fuzzy sphere
Volkholz, J. [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Bietenholz, W. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC
2007-11-15
We present a numerical study of a two dimensional model of the Wess-Zumino type. We formulate this model on a sphere, where the fields are expanded in spherical harmonics. The sphere becomes fuzzy by a truncation in the angular momenta. This leads to a finite set of degrees of freedom without explicitly breaking the space symmetries. The corresponding field theory is expressed in terms of a matrix model, which can be simulated. We present first numerical results for the phase structure of a variant of this model on a fuzzy sphere. The prospect to restore exact supersymmetry in certain limits is under investigation. (orig.)
Yangian symmetries in the SU(N)$_{1}$ WZW model and the Calogero-Sutherland model
Ahn, C; Ahn, Changhyun; Nam, Soonkeon
1995-01-01
We study the SU(N), level 1 Wess-Zumino-Witten model with affine primary fields, i.e. spinon fields obeying fractional statistics. By evaluating the action of the Yangian generators Q_{0}^{a}, Q_{1}^{a} and the Hamiltonian H_2 on two spinon states we get a new connection between this conformal field theory and the Calogero-Sutherland model with SU(N) spin. This connection clearly confirms the need for the W_3 generator in H_2 and an additional term in the Q^{a}_{1}.
Simulations of a supersymmetry inspired model on a fuzzy sphere
2008-01-01
We present a numerical study of a two dimensional model of the Wess-Zumino type. We formulate this model on a sphere, where the fields are expanded in spherical harmonics. The sphere becomes fuzzy by a truncation in the angular momenta. This leads to a finite set of degrees of freedom without explicitly breaking the space symmetries. The corresponding field theory is expressed in terms of a matrix model, which can be simulated. We present first numerical results for the phase structure of a v...
Leptonic CP violation in supersymmetric standard model
Joshipura, A S
1995-01-01
We point out the possibility of spontaneous and hard CP-violation in the scalar potential of R-parity broken supersymmetric Standard Model. The existence of spontaneous CP-violation depends crucially on the R-parity breaking terms in the superpotential and, in addition, on the choice of the soft supersymmetry breaking terms. Unlike in theories with R-parity conservation, it is natural, in the context of the present model, for the sneutrinos to acquire (complex) vacuum expectation values. In the context of this model we examine here the global implications, like the strength of the CP-violating interactions and the neutrino masses.
Geometry and duality in Supersymmetric $\\sigma$-Models
Curtright, T L; Zachos, C K; Curtright, Thomas; Uematsu, Tsuneo; Zachos, Cosmas
1996-01-01
The Supersymmetric Dual Sigma Model (SDSM) is a local field theory introduced to be nonlocally equivalent to the Supersymmetric Chiral nonlinear sigma-Model (SCM), this dual equivalence being proven by explicit canonical transformation in tangent space. This model is here reconstructed in superspace and identified as a chiral-entwined supersymmetrization of the Dual Sigma Model (DSM). This analysis sheds light on the Boson-Fermion Symphysis of the dual transition, and on the new geometry of the DSM.
Beyond the supersymmetric standard model
Hall, L.J.
1988-02-01
The possibility of baryon number violation at the weak scale and an alternative primordial nucleosynthesis scheme arising from the decay of gravitations are discussed. The minimal low energy supergravity model is defined and a few of its features are described. Renormalization group scaling and flavor physics are mentioned.
Ikeda, Noriaki; Xu, Xiaomeng
2014-11-01
Consistent boundary conditions for Alexandrov-Kontsevich-Schwartz-Zaboronsky (AKSZ) sigma models and the corresponding boundary theories are analyzed. As their mathematical structures, we introduce a generalization of differential graded symplectic manifolds, called twisted QP manifolds, in terms of graded symplectic geometry, canonical functions, and QP pairs. We generalize the AKSZ construction of topological sigma models to sigma models with Wess-Zumino terms and show that all the twisted Poisson-like structures known in the literature can actually be naturally realized as boundary conditions for AKSZ sigma models.
Higher Derivative CP(N) Model and Quantization of the Induced Chern-Simons Term
Itoh, T; Itoh, Taichi; Oh, Phillial
2001-01-01
We consider higher derivative CP(N) model in 2+1 dimensions with the Wess-Zumino-Witten term and the topological current density squared term. We quantize the theory by using the auxiliary gauge field formulation in the path integral method and prove that the extended model remains renormalizable in the large N limit. We also find that the Maxwell-Chern-Simons theory is dynamically induced in the large N effective action and the coefficient of the Chern-Simons term must be quantized.
寇谡鹏
2002-01-01
Used the dimensional reduction in the sense of Parisi and Sourlas,the gauge fixing term of the four-dimensional Yang-Mills field without the theta term is reduced to a two-dimensional principal chiral model,By adding the θ term (θ=π),the two-dimensional principal chiral model changes into the two-dimensional level 1 Wess-Zumino-Novikov-Witten model.The non-trivial fixed point indicates that Yang-Mills theory at θ=π is a critical theory without mass gap and confinement.
CP Violation in Supersymmetric U(1)' Models
Demir, D A
2004-01-01
The supersymmetric CP problem is studied within superstring-motivated extensions of the MSSM with an additional U(1)' gauge symmetry broken at the TeV scale. This class of models offers an attractive solution to the mu problem of the MSSM, in which U(1)' gauge invariance forbids the bare mu term, but an effective mu parameter is generated by the vacuum expectation value of a Standard Model singlet S which has superpotential coupling of the form SH_uH_d to the electroweak Higgs doublets. The effective mu parameter is thus dynamically determined as a function of the soft supersymmetry breaking parameters, and can be complex if the soft parameters have nontrivial CP-violating phases. We examine the phenomenological constraints on the reparameterization invariant phase combinations within this framework, and find that the supersymmetric CP problem can be greatly alleviated in models in which the phase of the SU(2) gaugino mass parameter is aligned with the soft trilinear scalar mass parameter associated with the ...
On supermatrix models, Poisson geometry, and noncommutative supersymmetric gauge theories
Klimčík, Ctirad [Aix Marseille Université, CNRS, Centrale Marseille I2M, UMR 7373, 13453 Marseille (France)
2015-12-15
We construct a new supermatrix model which represents a manifestly supersymmetric noncommutative regularisation of the UOSp(2|1) supersymmetric Schwinger model on the supersphere. Our construction is much simpler than those already existing in the literature and it was found by using Poisson geometry in a substantial way.
Gauge Unification from Split Supersymmetric String Models
Kokorelis, Christos
2016-01-01
We discuss the unification of gauge coupling constants in non-supersymmetric open string vacua that possess the properties of Split Supersymmetry, namely the Standard Model with Higgsinos at low energies and where the Standard model spectrum is always accompanied by right handed neutrinos. These vacua achieve partial unification of two out of three (namely SU(3)$_c$, SU(2), U(1)) running gauge couplings, possess massive gauginos and light Higgsinos at low energies and also satisfy $sin^2\\theta_w (M_s) = 3/8$. These vacua are based on four dimensional orbifold $Z_3 \\times Z_3$ compactifications of string IIA orientifolds with D6-branes intersecting at angles, where the (four dimensional) chiral fermions of the Standard Model appear as opens strings streching between the intersections of seven dimensional objects the so called D6-branes.
Supersymmetric One-family Model without Higgsinos
Mira, J M; Restrepo, D A; Sánchez, L A; Mira, Jesus M.; Ponce, William A.; Restrepo, Diego A.; Sanchez, Luis A.
2003-01-01
The Higgs potential and the mass spectrum of the N=1 supersymmetric extension of a recently proposed one-family model based on the local gauge group $SU(3)_c \\otimes SU(3)_L \\otimes U(1)_X$, which is a subgroup of the electroweak-strong unification group $E_6$, is analyzed. In this model the slepton multiplets play the role of the Higgs scalars and no Higgsinos are needed, with the consequence that the sneutrino, the selectron and six other sleptons play the role of the Goldstone bosons. We show how the $\\mu$ problem is successfully addressed in the context of this model which also predicts the existence of a light CP-odd scalar.
Simple supersymmetric strongly coupled preon model
Fajfer, S.; Tadić, D.
1988-08-01
This supersymmetric-SU(5) composite model is a natural generalization of the usual strong-coupling models. Preon superfields are in representations 5* and 10. The product representations 5*×10, 5×10, 5×5, and 5*×5 contain only those strongly hypercolor bound states which are needed in the standard electroweak theory. There are no superfluous quarklike states. The neutrino is massless. Only one strongly hypercolor bound singlet (10×10*) can exist as a free particle. At higher energies one should expect to see a plethora of new particles. Grand unification happens at the scale M~1014 GeV. Cabibbo mixing can be incorporated by using a transposed Kobayashi-Maskawa mixing matrix.
Supersymmetric Microscopic Theory of the Standard Model
Ter-Kazarian, G T
2000-01-01
We promote the microscopic theory of standard model (MSM, hep-ph/0007077) into supersymmetric framework in order to solve its technical aspects of vacuum zero point energy and hierarchy problems, and attempt, further, to develop its realistic viable minimal SUSY extension. Among other things that - the MSM provides a natural unification of geometry and the field theory, has clarified the physical conditions in which the geometry and particles come into being, in microscopic sense enables an insight to key problems of particle phenomenology and answers to some of its nagging questions - a present approach also leads to quite a new realization of the SUSY yielding a physically realistic particle spectrum. It stems from the special subquark algebra, from which the nilpotent supercharge operators are derived. The resulting theory makes plausible following testable implications for the current experiments at LEP2, at the Tevatron and at LHC drastically different from those of the conventional MSSM models: 1. All t...
Area law violations in a supersymmetric model
Huijse, Liza; Swingle, Brian
2013-01-01
We study the structure of entanglement in a supersymmetric lattice model of fermions on certain types of decorated graphs with quenched disorder. In particular, we construct models with controllable ground-state degeneracy protected by supersymmetry and the choice of Hilbert space. We show that in certain special limits, these degenerate ground states are associated with local impurities and that there exists a basis of the ground-state manifold in which every basis element satisfies a boundary law for entanglement entropy. On the other hand, by considering incoherent mixtures or coherent superpositions of these localized ground states, we can find regions that violate the boundary law for entanglement entropy over a wide range of length scales. More generally, we discuss various criteria for constructing violations of the boundary law for entanglement entropy and discuss possible relations of our work to recent holographic studies.
A tool box for implementing supersymmetric models
Staub, Florian; Ohl, Thorsten; Porod, Werner; Speckner, Christian
2012-10-01
We present a framework for performing a comprehensive analysis of a large class of supersymmetric models, including spectrum calculation, dark matter studies and collider phenomenology. To this end, the respective model is defined in an easy and straightforward way using the Mathematica package SARAH. SARAH then generates model files for CalcHep which can be used with micrOMEGAs as well as model files for WHIZARD and O'Mega. In addition, Fortran source code for SPheno is created which facilitates the determination of the particle spectrum using two-loop renormalization group equations and one-loop corrections to the masses. As an additional feature, the generated SPheno code can write out input files suitable for use with HiggsBounds to apply bounds coming from the Higgs searches to the model. Combining all programs provides a closed chain from model building to phenomenology. Program summary Program title: SUSY Phenomenology toolbox. Catalog identifier: AEMN_v1_0. Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEMN_v1_0.html. Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland. Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html. No. of lines in distributed program, including test data, etc.: 140206. No. of bytes in distributed program, including test data, etc.: 1319681. Distribution format: tar.gz. Programming language: Autoconf, Mathematica. Computer: PC running Linux, Mac. Operating system: Linux, Mac OS. Classification: 11.6. Nature of problem: Comprehensive studies of supersymmetric models beyond the MSSM is considerably complicated by the number of different tasks that have to be accomplished, including the calculation of the mass spectrum and the implementation of the model into tools for performing collider studies, calculating the dark matter density and checking the compatibility with existing collider bounds (in particular, from the Higgs searches). Solution method: The
The geometry of supersymmetric coset models and superconformal algebras
Papadopoulos, G
1993-01-01
An on-shell formulation of (p,q), 2\\leq p \\leq 4, 0\\leq q\\leq 4, supersymmetric coset models with target space the group G and gauge group a subgroup H of G is given. It is shown that there is a correspondence between the number of supersymmetries of a coset model and the geometry of the coset space G/H. The algebras of currents of supersymmetric coset models are superconformal algebras. In particular, the algebras of currents of (2,2) and (4,0) supersymmetric coset models are related to the N=2 Kazama-Suzuki and N=4 Van Proeyen superconformal algebras correspondingly.
LHC phenomenology of supersymmetric models beyond the MSSM
Porod, Werner
2010-01-01
We discuss various phenomenological aspects of supersymmetric models beyond the MSSM. A particular focus is on models which can correctly explain neutrino data and the possiblities of LHC to identify the underlying scenario.
On the structure of anomalous composite Higgs models
Gripaios, Ben; Nardecchia, Marco; You, Tevong
2017-01-01
We describe the anomaly structure of a composite Higgs model in which the SO(5) / SO(4) coset structure of the minimal model is extended by an additional, non-linearly realised U(1)_{η }. In addition, we show that the effective Lagrangian admits a term that, like the Wess-Zumino-Witten term in the chiral Lagrangian for QCD, is not invariant under the non-linearly realised symmetries, but rather changes by a total derivative. This term is unlike the Wess-Zumino-Witten term in that it does not arise from anomalies. If present, it may give rise to the rare decay η → h W^+ W^-Z. The phenomenology of the singlet in this model differs from that in a model based on SO(6) / SO(5), in that couplings to both gluons and photons, arising via anomalies, are present. We show that while some tuning is needed to accommodate flavour and electroweak precision constraints, the model is no worse than the minimal model in this regard.
Particle Physics And Cosmology In Supersymmetric Models
Morrissey, D E
2005-01-01
The Standard Model (SM) of particle physics provides an excellent description of the elementary particle interactions observed in particle collider experiments, but the model does less well when it is applied to cosmology. Recent measurements of the Universe over very large distances indicate the existence of non-luminous dark matter and an excess of baryons over anti-baryons. The SM is unable to account for either of these results, implying that an extension of the SM description is needed. One such extension is supersymmetry. Within the minimal supersymmetric version of the SM, the MSSM, the lightest superpartner particle can make up the dark matter, and the baryon asymmetry can be generated by the mechanism of electroweak baryogenesis (EWBG). In this work, we examine these issues together in order to find out whether the MSSM can account for both of them simultaneously. We find that the MSSM can explain both the baryon asymmetry and the dark matter, but only over a very constrained region of the model para...
Beyond the standard gauging: gauge symmetries of Dirac sigma models
Chatzistavrakidis, Athanasios; Deser, Andreas; Jonke, Larisa; Strobl, Thomas
2016-08-01
In this paper we study the general conditions that have to be met for a gauged extension of a two-dimensional bosonic σ-model to exist. In an inversion of the usual approach of identifying a global symmetry and then promoting it to a local one, we focus directly on the gauge symmetries of the theory. This allows for action functionals which are gauge invariant for rather general background fields in the sense that their invariance conditions are milder than the usual case. In particular, the vector fields that control the gauging need not be Killing. The relaxation of isometry for the background fields is controlled by two connections on a Lie algebroid L in which the gauge fields take values, in a generalization of the common Lie-algebraic picture. Here we show that these connections can always be determined when L is a Dirac structure in the H-twisted Courant algebroid. This also leads us to a derivation of the general form for the gauge symmetries of a wide class of two-dimensional topological field theories called Dirac σ-models, which interpolate between the G/G Wess-Zumino-Witten model and the (Wess-Zumino-term twisted) Poisson sigma model.
A supersymmetric composite model of quarks and leptons
Luty, Markus A.; Mohapatra, Rabindra N.
1997-02-01
We present a class of supersymmetric models with complete generations of composite quarks and leptons using recent non-perturbative results for the low energy dynamics of supersymmetric QCD. In these models, the quarks arise as composite ``mesons'' and the leptons emerge as composite ``baryons''. The quark and lepton flavor symmetries are linked at the preon level. Baryon number violation is automatically suppressed by accidental symmetries. We give some speculations on how this model might be made realistic.
Supersymmetric Q-Lumps in the Grassmannian nonlinear sigma models
Bak, D; Lee, J; Oh, P; Bak, Dongsu; Hahn, Sang-Ok; Lee, Joohan; Oh, Phillial
2007-01-01
We construct the N=2 supersymmetric Grassmannian nonlinear sigma model for the massless case and extend it to massive N=2 model by adding an appropriate superpotential. We then study their BPS equations leading to supersymmetric Q-lumps carrying both topological and Noether charges. These solutions are shown to be always time dependent even sometimes involving multiple frequencies. Thus we illustrate explicitly that the time dependence is consistent with remaining supersymmetries of solitons.
A lattice study of N=2 Landau-Ginzburg model using a Nicolai map
Kawai, Hiroki
2010-01-01
It has been conjectured that the two-dimensional N=2 Wess-Zumino model with a quasi-homogeneous superpotential provides the Landau-Ginzburg description of the N=2 superconformal minimal models. For the cubic superpotential W=(lambda) Phi^3/3, it is expected that the Wess-Zumino model describes A_{2} model (c=1) and the chiral superfield Phi shows the conformal weight (h,bar{h})=(1/6,1/6) at the IR fixed point. We study this conjecture by a lattice simulation, extracting the weight from the finite volume scaling of the susceptibility of the scalar component in Phi. We adopt a lattice model with the overlap fermion, which possesses a Nicolai map and a discrete R-symmetry. We set a(lambda)=0.3 and generate the scalar field configurations by solving the Nicolai map on L times L lattices in the range L=18 - 32. To solve the map, we use the Newton-Raphson algorithm with various initial configurations. The result is 1-h-bar{h}=0.660 \\pm0.011, which is consistent with the conjecture.
Particle physics and cosmology in supersymmetric models
Morrissey, David Edgar
The Standard Model (SM) of particle physics provides an excellent description of the elementary particle interactions observed in particle collider experiments, but the model does less well when it is applied to cosmology. Recent measurements of the Universe over very large distances indicate the existence of non-luminous dark matter and an excess of baryons over anti-baryons. The SM is unable to account for either of these results, implying that an extension of the SM description is needed. One such extension is supersymmetry. Within the minimal supersymmetric version of the SM, the MSSM, the lightest superpartner particle can make up the dark matter, and the baryon asymmetry can be generated by the mechanism of electroweak baryogenesis (EWBG). In this work, we examine these issues together in order to find out whether the MSSM can account for both of them simultaneously. We find that the MSSM can explain both the baryon asymmetry and the dark matter, but only over a very constrained region of the model parameter space. The strongest constraints on this scenario come from the lower bound on the Higgs boson mass, and the upper bound on the electric dipole moment of the electron. Moreover, upcoming experiments will probe the remaining allowed parameter space in the near future. Some of these constraints may be relaxed by going beyond the MSSM. With this in mind, we also investigate the nMSSM, a minimal singlet extension of the MSSM. We find that this model can also explain both the dark matter and the baryon asymmetry.
Yasmin, Safia; Rahaman, Anisur
2016-12-01
A (1+1) dimensional model where vector and axial vector interaction get mixed up with different weight is considered with a generalized masslike term for gauge field. Through Poincaré algebra it has been made confirm that only a Lorentz covariant masslike term leads to a physically sensible theory as long as the number of constraints in the phase space is two. With that admissible masslike term, phase space structure of this model with proper identification of physical canonical pair has been determined using Diracs' scheme of quantization of constrained system. The bosonized version of the model remains gauge non-invariant to start with. Therefore, with the inclusion of appropriate Wess-Zumino term it is made gauge symmetric. An alternative quantization has been carried out over this gauge symmetric version to determine the phase space structure in this situation. To establish that the Wess-Zumino fields allocates themselves in the un-physical sector of the theory an attempts has been made to get back the usual theory from the gauge symmetric theory of the extended phase-space without hampering any physical principle. It has been found that the role of gauge fixing is crucial for this transmutation.
Yasmin, Safia
2016-01-01
A $(1+1)$ dimensional model where vector and axial vector interaction get mixed up with different weight is considered with a generalized masslike term for gauge field. Through Poincar\\'e algebra it has been made confirm that only a Lorentz covariant masslike term leads to a physically sensible theory as long as the number of constraints in the phase space is two. With that admissible masslike term, phase space structure of this model with proper identification of physical canonical pair has been determined using Diracs' scheme of quantization of constrained system. The bosonized version of the model remains gauge non-invariant to start with. Therefore, with the inclusion of appropriate Wess-Zumino term it is made gauge symmetric. An alternative quantization has been carried out over this gauge symmetric version to determine the phase space structure in this situation. To establish that the Wess-Zumino fields allocates themselves in the un-physical sector of the theory an attempts has been made to get back th...
D-brane Solitons in Supersymmetric Sigma-Models
Gauntlett, J P; Tong, D; Townsend, P K; Gauntlett, Jerome P.; Portugues, Rubén; Tong, David; Townsend, Paul K.
2001-01-01
Massive D=4 N=2 supersymmetric sigma models typically admit domain wall (Q-kink) solutions and string (Q-lump) solutions, both preserving 1/2 supersymmetry. We exhibit a new static 1/4 supersymmetric `kink-lump' solution in which a string ends on a wall, and show that it has an effective realization as a BIon of the D=4 super DBI-action. It is also shown to have a time-dependent Q-kink-lump generalization which reduces to the Q-lump in a limit corresponding to infinite BI magnetic field. All these 1/4 supersymmetric sigma-model solitons are shown to be realized in M-theory as calibrated, or `Q-calibrated', M5-branes in an M-monopole background.
A review of Higgs mass calculations in supersymmetric models
Draper, P.; Rzehak, H.
2016-01-01
related to the electroweak hierarchy problem. Perhaps the most extensively studied examples are supersymmetric models, which, while capable of producing a 125 GeV Higgs boson with SM-like properties, do so in non-generic parts of their parameter spaces. We review the computation of the Higgs mass...... in the Minimal Supersymmetric Standard Model, in particular the large radiative corrections required to lift mh to 125 GeV and their calculation via Feynman-diagrammatic and effective field theory techniques. This review is intended as an entry point for readers new to the field, and as a summary of the current...
Diphoton Revelation of the Utilitarian Supersymmetric Standard Model
Ma, Ernest
2016-01-01
In 2002, I proposed a unique $U(1)$ extension of the supersymmetric standard model which has no $\\mu$ term and conserves baryon number and lepton number separately and automatically. This model, ${without~any~change}$, has all the necessary and sufficient ingredients to explain the possible 750 GeV diphoton excess, observed recently by the ATLAS Collaboration at the Large Hadron Collider (LHC).
Non-minimal supersymmetric models. LHC phenomenolgy and model discrimination
Krauss, Manuel Ernst
2015-12-18
It is generally agreed upon the fact that the Standard Model of particle physics can only be viewed as an effective theory that needs to be extended as it leaves some essential questions unanswered. The exact realization of the necessary extension is subject to discussion. Supersymmetry is among the most promising approaches to physics beyond the Standard Model as it can simultaneously solve the hierarchy problem and provide an explanation for the dark matter abundance in the universe. Despite further virtues like gauge coupling unification and radiative electroweak symmetry breaking, minimal supersymmetric models cannot be the ultimate answer to the open questions of the Standard Model as they still do not incorporate neutrino masses and are besides heavily constrained by LHC data. This does, however, not derogate the beauty of the concept of supersymmetry. It is therefore time to explore non-minimal supersymmetric models which are able to close these gaps, review their consistency, test them against experimental data and provide prospects for future experiments. The goal of this thesis is to contribute to this process by exploring an extraordinarily well motivated class of models which bases upon a left-right symmetric gauge group. While relaxing the tension with LHC data, those models automatically include the ingredients for neutrino masses. We start with a left-right supersymmetric model at the TeV scale in which scalar SU(2){sub R} triplets are responsible for the breaking of left-right symmetry as well as for the generation of neutrino masses. Although a tachyonic doubly-charged scalar is present at tree-level in this kind of models, we show by performing the first complete one-loop evaluation that it gains a real mass at the loop level. The constraints on the predicted additional charged gauge bosons are then evaluated using LHC data, and we find that we can explain small excesses in the data of which the current LHC run will reveal if they are actual new
The Minimal Supersymmetric Model without a mu term
Nelson, A E; Sanz, V; Unsal, M; Nelson, Ann E.; Rius, Nuria; Sanz, Veronica; Unsal, Mithat
2002-01-01
We propose a supersymmetric extension of the standard model which is a realistic alternative to the MSSM, and which has several advantages. No ``mu'' supersymmetric Higgs/Higgsino mass parameter is needed for sufficiently heavy charginos. An approximate U(1) R symmetry naturally guarantees that tan beta is large, explaining the top/bottom quark mass hierarchy. This symmetry also suppresses supersymmetric contributions to anomalous magnetic moments, b to s gamma, and proton decay, and these processes place no lower bounds on superpartner masses, even at large tan beta. The soft supersymmetry breaking mass parameters can easily be obtained from either gauge or Planck scale mediation, without the usual mu problem. Unlike in the MSSM, there are significant upper bounds on the masses of superpartners, including an upper bound of 114 GeV on the mass of the lightest chargino. However the MSSM bound on the lightest Higgs mass does not apply.
Metastable Vacua in Deformed N=2 Supersymmetric Models
Halyo, Edi
2009-01-01
We show that supersymmetric Abelian models that are obtained from deformations of those with ${\\cal N}=2$ supersymmetry also contain metastable vacua for a wide range of parameters. The deformations we consider are combinations of masses for charged and singlet fields, a singlet F--term and an anomalous D--term. We find that, in all cases, the nonsupersymmetric vacua are parametrically far from the supersymmetric ones and therefore metastable. Using retrofitting, we show that these metastable vacua may lead to semi--realistic phenomenology.
Neutrino masses within the minimal supersymmetric Standard Model
Cvetic, M; Cvetic, Mirjam; Langacker, Paul
1992-01-01
We investigate the possibility of accommodating neutrino masses compatible with the MSW study of the Solar neutrino deficit within the minimal supersymmetric Standard Model. The ``gravity-induced'' seesaw mechanism based on an interplay of nonrenormalizable and renormalizable terms in the superpotential allows neutrino masses $m_\
Large BR(h -> tau mu) in Supersymmetric Models
Hammad, Ahmed; Un, Cem Salih
2016-01-01
We analyze the Lepton Flavor Violating (LFV) Higgs decay h -> tau mu in three supersymmetric models: Minimal Supersymmetric Standard Model (MSSM), Supersymmetric Seesaw Model (SSM), and Supersymmetric B-L model with Inverse Seesaw (BLSSM-IS). We show that in generic MSSM, with non-universal slepton masses and/or trilinear couplings, it is not possible to enhance BR(h -> tau mu) without violating the experimental bound on the BR(tau -> mu gamma). In SSM, where flavor mixing is radiatively generated, the LFV process mu -> e gamma strictly constrains the parameter space and the maximum value of BR(h -> tau mu) is of order 10^-10, which is extremely smaller than the recent results reported by the CMS and ATLAS experiments. In BLSSM-IS, with universal soft SUSY breaking terms at the grand unified scale, we emphasize that the measured values of BR(h -> tau mu) can be accommodated in a wide region of parameter space without violating LFV constraints. Thus, confirming the LFV Higgs decay results will be a clear signa...
Higher-Rank Supersymmetric Models and Topological Field Theory
Kawai, T; Yang, S K; Kawai, Toshiya; Uchino, Taku; Yang, Sung-Kil
1993-01-01
In the first part of this paper we investigate the operator aspect of higher-rank supersymmetric model which is introduced as a Lie theoretic extension of the $N=2$ minimal model with the simplest case $su(2)$ corresponding to the $N=2$ minimal model. In particular we identify the analogs of chirality conditions and chiral ring. In the second part we construct a class of topological conformal field theories starting with this higher-rank supersymmetric model. We show the BRST-exactness of the twisted stress-energy tensor, find out physical observables and discuss how to make their correlation functions. It is emphasized that in the case of $su(2)$ the topological field theory constructed in this paper is distinct from the one obtained by twisting the $N=2$ minimal model through the usual procedure.
Quasicomplex N=2, d=1 Supersymmetric Sigma Models
Evgeny A. Ivanov
2013-11-01
Full Text Available We derive and discuss a new type of N=2 supersymmetric quantum mechanical sigma models which appear when the superfield action of the (1,2,1 multiplets is modified by adding an imaginary antisymmetric tensor to the target space metric, thus completing the latter to a non-symmetric Hermitian metric. These models are not equivalent to the standard de Rham sigma models, but are related to them through a certain special similarity transformation of the supercharges. On the other hand, they can be obtained by a Hamiltonian reduction from the complex supersymmetric N=2 sigma models built on the multiplets (2,2,0 and describing the Dolbeault complex on the manifolds with proper isometries. We study in detail the extremal two-dimensional case, when the target space metric is defined solely by the antisymmetric tensor, and show that the corresponding quantum systems reveal a hidden N=4 supersymmetry.
Supersymmetric Composite Models on Intersecting D-branes
Kitazawa, N
2004-01-01
We construct supersymmetric composite models of quarks and leptons from type IIA T^6/(Z_2 x Z_2) orientifolds with intersecting D6-branes. In case of T^6 = T^2 x T^2 x T^2 with no tilted T^2, a composite model of the supersymmetric SU(5) grand unified theory with three generations is constructed. In case of that one T^2 is tilted, a composite model with SU(3)_c x SU(2)_L x U(1)_Y gauge symmetry with three generations is constructed. These models are not realistic, but contain fewer additional exotic particles and U(1) gauge symmetries due to the introduction of the compositeness of quarks and leptons. The mu-term of Higgs fields can be naturally generated through the exponentially suppressed Yukawa interaction among "preons".
Supersymmetric standard model from the heterotic string (II)
Buchmueller, W. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Hamaguchi, K. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[Tokyo Univ. (Japan). Dept. of Physics; Lebedev, O.; Ratz, M. [Bonn Univ. (Germany). Physikalisches Inst.
2006-06-15
We describe in detail a Z{sub 6} orbifold compactification of the heterotic E{sub 8} x E{sub 8} string which leads to the (supersymmetric) standard model gauge group and matter content. The quarks and leptons appear as three 16-plets of SO(10), two of which are localized at fixed points with local SO(10) symmetry. The model has supersymmetric vacua without exotics at low energies and is consistent with gauge coupling unification. Supersymmetry can be broken via gaugino condensation in the hidden sector. The model has large vacuum degeneracy. Certain vacua with approximate B-L symmetry have attractive phenomenological features. The top quark Yukawa coupling arises from gauge interactions and is of the order of the gauge couplings. The other Yukawa couplings are suppressed by powers of standard model singlet fields, similarly to the Froggatt-Nielsen mechanism. (Orig.)
Neutralino Relic Density in a Supersymmetric U(1)' Model
Barger, V; Langacker, P; Lee, H S; Barger, Vernon; Kao, Chung; Langacker, Paul; Lee, Hye-Sung
2004-01-01
We study properties of the lightest neutralino (\\chi) and calculate its cosmological relic density in a supersymmetric U(1)' model with a secluded U(1)' breaking sector (the S-model). The lightest neutralino mass is smaller than in the minimal supersymmetric standard model; for instance, m_\\chi < 100 GeV in the limit that the U(1)' gaugino mass is large compared to the electroweak scale. We find that the Z-\\chi-\\chi coupling can be enhanced due to the singlino components in the extended neutralino sector. Neutralino annihilation through the Z-resonance then reproduces the measured cold dark matter density over broad regions of the model parameter space.
N=2 supersymmetric sigma-models in AdS
Butter, Daniel
2011-01-01
We construct the most general N=2 supersymmetric nonlinear sigma-model in four-dimensional anti-de Sitter (AdS) space in terms of N=1 chiral superfields. The target space is shown to be a non-compact hyperkahler manifold restricted to possess a special Killing vector field. A remarkable property of the sigma-model constructed is that the algebra of OSp(2|4) transformations is closed off the mass shell.
Supersymmetric Extension of the Standard Model with Naturally Stable Proton
Aoki, M; Aoki, Mayumi; Oshimo, Noriyuki
2000-01-01
A new supersymmetric standard model based on N=1 supergravity is constructed, aiming at natural explanation for the proton stability without invoking an ad hoc discrete symmetry through R parity. The proton is protected from decay by an extra U(1) gauge symmetry. Particle contents are necessarily increased to be free from anomalies, making it possible to incorporate the superfields for right-handed neutrinos and an SU(2)-singlet Higgs boson. The vacuum expectation value of this Higgs boson, which induces spontaneous breakdown of the U(1) symmetry, yields large Majorana masses for the right-handed neutrinos, leading to small masses for the ordinary neutrinos. The linear coupling of SU(2)-doublet Higgs superfields, which is indispensable to the superpotential of the minimal supersymmetric standard model, is replaced by a trilinear coupling of the Higgs superfields, so that there is no mass parameter in the superpotential. The energy dependencies of the model parameters are studied, showing that gauge symmetry b...
Supersymmetric Theory of Stochastic ABC Model: A Numerical Study
Ovchinnikov, Igor V; Ensslin, Torsten A; Wang, Kang L
2016-01-01
In this paper, we investigate numerically the stochastic ABC model, a toy model in the theory of astrophysical kinematic dynamos, within the recently proposed supersymmetric theory of stochastics (STS). STS characterises stochastic differential equations (SDEs) by the spectrum of the stochastic evolution operator (SEO) on elements of the exterior algebra or differentials forms over the system's phase space, X. STS can thereby classify SDEs as chaotic or non-chaotic by identifying the phenomenon of stochastic chaos with the spontaneously broken topological supersymmetry that all SDEs possess. We demonstrate the following three properties of the SEO, deduced previously analytically and from physical arguments: the SEO spectra for zeroth and top degree forms never break topological supersymmetry, all SDEs possesses pseudo-time-reversal symmetry, and each de Rahm cohomology class provides one supersymmetric eigenstate. Our results also suggests that the SEO spectra for forms of complementary degrees, i.e., k and ...
Radiative fermion mass matrix generation in supersymmetric models
Papantonopoulos, E.; Zoupanos, G.
1984-01-01
Supersymmetric SU(2)sub(L)xU(1) horizontal models are studied. The non-renormalisation theorems of sypersymmetry are used to make the mass generation and flavour mixing natural. For three families, the fermion mass matrix generation mechanism is studied as a radiative effect due to horizontal interactions, using various representations of the gauge horizontal groups SU(2)sub(H) and SU(3)sub(H). An attractive possibility leading to a realistic mass matrix is found.
Electric Dipole Moments of Neutron and Electron in Supersymmetric Model
Aoki, Mayumi; Kadoyoshi, Tomoko; Sugamoto, Akio; Oshimo, Noriyuki
1997-01-01
The electric dipole moments (EDMs) of the neutron and the electron are reviewed within the framework of the supersymmetric standard model (SSM) based on grand unified theories coupled to N=1 supergravity. Taking into account one-loop and two-loop contributions to the EDMs, we explore SSM parameter space consistent with experiments and discuss predicted values for the EDMs. Implications of baryon asymmetry of our universe for the EDMs are also discussed.
Matrix models, topological strings, and supersymmetric gauge theories
Dijkgraaf, Robbert; Vafa, Cumrun
2002-11-01
We show that B-model topological strings on local Calabi-Yau threefolds are large- N duals of matrix models, which in the planar limit naturally give rise to special geometry. These matrix models directly compute F-terms in an associated N=1 supersymmetric gauge theory, obtained by deforming N=2 theories by a superpotential term that can be directly identified with the potential of the matrix model. Moreover by tuning some of the parameters of the geometry in a double scaling limit we recover ( p, q) conformal minimal models coupled to 2d gravity, thereby relating non-critical string theories to type II superstrings on Calabi-Yau backgrounds.
On Affine Fusion and the Phase Model
Mark A. Walton
2012-11-01
Full Text Available A brief review is given of the integrable realization of affine fusion discovered recently by Korff and Stroppel. They showed that the affine fusion of the su(n Wess-Zumino-Novikov-Witten (WZNW conformal field theories appears in a simple integrable system known as the phase model. The Yang-Baxter equation leads to the construction of commuting operators as Schur polynomials, with noncommuting hopping operators as arguments. The algebraic Bethe ansatz diagonalizes them, revealing a connection to the modular S matrix and fusion of the su(n WZNW model. The noncommutative Schur polynomials play roles similar to those of the primary field operators in the corresponding WZNW model. In particular, their 3-point functions are the su(n fusion multiplicities. We show here how the new phase model realization of affine fusion makes obvious the existence of threshold levels, and how it accommodates higher-genus fusion.
Ellis, John; Savage, Christopher; Spanos, Vassilis C
2010-01-01
We evaluate the neutrino fluxes to be expected from neutralino LSP annihilations inside the Sun, within the minimal supersymmetric extension of the Standard Model with supersymmetry-breaking scalar and gaugino masses constrained to be universal at the GUT scale (the CMSSM). We find that there are large regions of typical CMSSM $(m_{1/2}, m_0)$ planes where the LSP density inside the Sun is not in equilibrium, so that the annihilation rate may be far below the capture rate. We show that neutrino fluxes are dependent on the solar model at the 20% level, and adopt the AGSS09 model of Serenelli et al. for our detailed studies. We find that there are large regions of the CMSSM $(m_{1/2}, m_0)$ planes where the capture rate is not dominated by spin-dependent LSP-proton scattering, e.g., at large $m_{1/2}$ along the CMSSM coannihilation strip. We calculate neutrino fluxes above various threshold energies for points along the coannihilation/rapid-annihilation and focus-point strips where the CMSSM yields the correct ...
Minimum Supersymmetric Standard Model on the Noncommutative Geometry
Ishihara, Satoshi; Matsukawa, Atsuko; Sato, Hikaru; Shimojo, Masafumi
2013-01-01
We have obtained the supersymmetric extension of spectral triple which specify a noncommutative geometry(NCG). We assume that the functional space H constitutes of wave functions of matter fields and their superpartners included in the minimum supersymmetric standard model(MSSM). We introduce the internal fluctuations to the Dirac operator on the manifold as well as on the finite space by elements of the algebra A in the triple. So, we obtain not only the vector supermultiplets which meditate SU(3)xSU(2)xU(1)_Y gauge degrees of freedom but also Higgs supermultiplets which appear in MSSM on the same standpoint. Accoding to the supersymmetric version of the spectral action principle, we calculate the square of the fluctuated total Dirac operator and verify that the Seeley-DeWitt coeffients give the correct action of MSSM. We also verify that the relation between coupling constants of $SU(3)$,$SU(2)$ and $U(1)_Y$ is same as that of SU(5) unification theory.
Phenomenology of the Little Higgs model with X-Parity
Freitas, A; Wyler, D
2009-01-01
In the popular littlest Higgs model, T-parity can be broken by Wess-Zumino-Witten (WZW) terms induced by a strongly coupled UV completion. On the other hand, certain models with multiple scalar multiplets (called moose models) permit the implementation of an exchange symmetry (X-parity) such that it is not broken by the WZW terms. Here we present a concrete and realistic construction of such a model. The little Higgs model with X-Parity is a concrete and realistic implementation of this idea. In this contribution, the properties of the model are reviewed and the collider phenomenology is discussed in some detail. We also present new results on the decay properties and LHC signatures of the light triplet scalars that are predicted by this model.
Flipped version of the supersymmetric strongly coupled preon model
Fajfer, S.; Mileković, M.; Tadić, D.
1989-12-01
In the supersymmetric SU(5) [SUSY SU(5)] composite model (which was described in an earlier paper) the fermion mass terms can be easily constructed. The SUSY SU(5)⊗U(1), i.e., flipped, composite model possesses a completely analogous composite-particle spectrum. However, in that model one cannot construct a renormalizable superpotential which would generate fermion mass terms. This contrasts with the standard noncomposite grand unified theories (GUT's) in which both the Georgi-Glashow electrical charge embedding and its flipped counterpart lead to the renormalizable theories.
Required experimental accuracy to select between supersymmetrical models
David Grellscheid
2004-03-01
We will present a method to decide a priori whether various supersymmetrical scenarios can be distinguished based on sparticle mass data alone. For each model, a scan over all free SUSY breaking parameters reveals the extent of that model's physically allowed region of sparticle-mass-space. Based on the geometrical configuration of these regions in mass-space, it is possible to obtain an estimate of the required accuracy of future sparticle mass measurements to distinguish between the models. We will illustrate this algorithm with an example. Ths talk is based on work done in collaboration with B C Allanach (LAPTH, Annecy) and F Quevedo (DAMTP, Cambridge).
Early universe cosmology. In supersymmetric extensions of the standard model
Baumann, Jochen Peter
2012-03-19
In this thesis we investigate possible connections between cosmological inflation and leptogenesis on the one side and particle physics on the other side. We work in supersymmetric extensions of the Standard Model. A key role is played by the right-handed sneutrino, the superpartner of the right-handed neutrino involved in the type I seesaw mechanism. We study a combined model of inflation and non-thermal leptogenesis that is a simple extension of the Minimal Supersymmetric Standard Model (MSSM) with conserved R-parity, where we add three right-handed neutrino super fields. The inflaton direction is given by the imaginary components of the corresponding scalar component fields, which are protected from the supergravity (SUGRA) {eta}-problem by a shift symmetry in the Kaehler potential. We discuss the model first in a globally supersymmetric (SUSY) and then in a supergravity context and compute the inflationary predictions of the model. We also study reheating and non-thermal leptogenesis in this model. A numerical simulation shows that shortly after the waterfall phase transition that ends inflation, the universe is dominated by right-handed sneutrinos and their out-of-equilibrium decay can produce the desired matter-antimatter asymmetry. Using a simplified time-averaged description, we derive analytical expressions for the model predictions. Combining the results from inflation and leptogenesis allows us to constrain the allowed parameter space from two different directions, with implications for low energy neutrino physics. As a second thread of investigation, we discuss a generalisation of the inflationary model discussed above to include gauge non-singlet fields as inflatons. This is motivated by the fact that in left-right symmetric, supersymmetric Grand Unified Theories (SUSY GUTs), like SUSY Pati-Salam unification or SUSY SO(10) GUTs, the righthanded (s)neutrino is an indispensable ingredient and does not have to be put in by hand as in the MSSM. We discuss
Hidden Symmetry of a Fluid Dynamical Model
Neves, C
2001-01-01
A connection between solutions of the relativistic d-brane system in (d+1) dimensions with the solutions of a Galileo invariant fluid in d-dimensions is by now well established. However, the physical nature of the light-cone gauge description of a relativistic membrane changes after the reduction to the fluid dynamical model since the gauge symmetry is lost. In this work we argue that the original gauge symmetry present in a relativistic d-brane system can be recovered after the reduction process to a d-dimensional fluid model. To this end we propose, without introducing Wess-Zumino fields, a gauge invariant theory of isentropic fluid dynamics and show that this symmetry corresponds to the invariance under local translation of the velocity potential in the fluid dynamics picture. We show that different but equivalent choices of the sympletic sector lead to distinct representations of the embedded gauge algebra.
Supersymmetric Matrix model on Z-orbifold
Miyake, A
2003-01-01
We find that the IIA Matrix models defined on the non-compact $C^3/Z_6$, $C^2/Z_2$ and $C^2/Z_4$ orbifolds preserve supersymmetry where the fermions are on-mass-shell Majorana-Weyl fermions. In these examples supersymmetry is preserved both in the orbifolded space and in the non-orbifolded space at the same time. The Matrix model on $C^3/Z_6$ orbifold has the same ${\\cal N}=2$ supersymmetry as the case of $C^3/Z_3$ orbifold, whose particular case was previously pointed out. On the other hand the Matrix models on $C^2/Z_2$ and $C^2/Z_4$ orbifold have a half of the ${\\cal N}=2$ supersymmetry. We further find that the Matrix model on $C^2/Z_2$ orbifold with parity-like identification preserves ${\\cal N}=2$ supersymmetry both in the orbifolded space and non-orbifolded space, and furthermore has ${\\cal N}=4$ supersymmetry parameters in the total space.
Supersymmetric extension of the minimal dark matter model
CHANG Xue; LIU Chun; MA Feng-Cai; YANG Shuo
2012-01-01
The minimal dark matter model is given a supersymmetric extension.A super SU(2)L quintuplet is introduced with its fermionic neutral component still being the dark matter,and the dark matter mass is about 19.7 TeV.Mass splitting among the quintplet due to supersymmetry particles is found to be negligibly small compared to the electroweak corrections.Other properties of this supersymmetry model are studied,it has the solutions to the PAMELA and Fermi-LAT anomaly,and the predictions in higher energies need further experimental data to verify them.
Supersymmetric structures in topological field models
Pisar, T
2000-01-01
formalism with the latter proposed method. Besides the calculation of the vector supersymmetry the formalism admits the derivation of another scalar supersymmetry which is present in some particular models. The work is organized as follows. In Chapter 2 we give the technical details, Chapter 3 presents a review of the relevant aspects of topological field theories, in Chapter 4 we introduce a formalism which admits the calculation of the vectorial supersymmetry of the basic fields, and the following Chapter 5 demonstrates its application in the case of a six-dimensional Witten type model. Chapter 6 combines this method with the Batalin-Vilkovisky formalism, also including the BRST doublets and Chapter 7 gives three different applications of the latter procedure. During the eighties topological quantum field theory appears the first time as a new link between topology and quantum field theory. In the actual understanding we distinguish two types of topological field theories, the first one originally introduce...
A Little Higgs Model with Exact Dark Matter Parity
Freitas, A; Wyler, D
2009-01-01
Based on a recent idea by Krohn and Yavin, we construct a little Higgs model with an internal parity that is not broken by anomalous Wess-Zumino-Witten terms. The model is a modification of the "minimal moose" models by Arkani-Hamed et al. and Cheng and Low. The new parity prevents large corrections to oblique electroweak parameters and leads to a viable dark matter candidate. It is shown how the complete Standard Model particle content, including quarks and leptons together with their Yukawa couplings, can be implemented. Successful electroweak symmetry breaking and consistency with electroweak precision constraints is achieved for natural paramters choices. A rich spectrum of new particles is predicted at the TeV scale, some of which have sizable production cross sections and striking decay signatures at the LHC.
Phenomenology of non-minimal supersymmetric models at linear colliders
Porto, Stefano
2015-06-15
The focus of this thesis is on the phenomenology of several non-minimal supersymmetric models in the context of future linear colliders (LCs). Extensions of the minimal supersymmetric Standard Model (MSSM) may accommodate the observed Higgs boson mass at about 125 GeV in a more natural way than the MSSM, with a richer phenomenology. We consider both F-term extensions of the MSSM, as for instance the non-minimal supersymmetric Standard Model (NMSSM), as well as D-terms extensions arising at low energies from gauge extended supersymmetric models. The NMSSM offers a solution to the μ-problem with an additional gauge singlet supermultiplet. The enlarged neutralino sector of the NMSSM can be accurately studied at a LC and used to distinguish the model from the MSSM. We show that exploiting the power of the polarised beams of a LC can be used to reconstruct the neutralino and chargino sector and eventually distinguish the NMSSM even considering challenging scenarios that resemble the MSSM. Non-decoupling D-terms extensions of the MSSM can raise the tree-level Higgs mass with respect to the MSSM. This is done through additional contributions to the Higgs quartic potential, effectively generated by an extended gauge group. We study how this can happen and we show how these additional non-decoupling D-terms affect the SM-like Higgs boson couplings to fermions and gauge bosons. We estimate how the deviations from the SM couplings can be spotted at the Large Hadron Collider (LHC) and at the International Linear Collider (ILC), showing how the ILC would be suitable for the model identication. Since our results prove that a linear collider is a fundamental machine for studying supersymmetry phenomenology at a high level of precision, we argue that also a thorough comprehension of the physics at the interaction point (IP) of a LC is needed. Therefore, we finally consider the possibility of observing intense electromagnetic field effects and nonlinear quantum electrodynamics
E6 inspired supersymmetric models with exact custodial symmetry
Nevzorov, Roman
2013-01-01
The breakdown of E6 gauge symmetry at high energies may lead to supersymmetric models based on the standard model gauge group together with extra U(1)ψ and U(1)χ gauge symmetries. To ensure anomaly cancellation the particle content of these E6 inspired models involves extra exotic states that generically give rise to nondiagonal flavor transitions and rapid proton decay. We argue that a single discrete Z˜2H symmetry can be used to forbid tree-level flavor changing transitions, as well as the most dangerous baryon and lepton number violating operators. We present 5D and 6D orbifold grand unified theory constructions that lead to the E6 inspired supersymmetric models of this type. The breakdown of U(1)ψ and U(1)χ gauge symmetries that preserves E6 matter parity assignment guarantees that ordinary quarks and leptons and their superpartners, as well as the exotic states which originate from 27 representations of E6, survive to low energies. These E6 inspired models contain two dark matter candidates and must also include additional TeV scale vectorlike lepton or vectorlike down-type quark states to render the lightest exotic quark unstable. We examine gauge coupling unification in these models and discuss their implications for collider phenomenology and cosmology.
Muon Anomalous Magnetic Moment in a Supersymmetric U(1)' Model
Barger, V; Langacker, P; Lee, H S; Barger, Vernon; Kao, Chung; Langacker, Paul; Lee, Hye-Sung
2005-01-01
We study the muon anomalous magnetic moment a_\\mu = (g_\\mu - 2)/2 in a supersymmetric U(1)' model. The neutralino sector has extra components from the superpartners of the U(1)' gauge boson and the extra Higgs singlets that break the U(1)' symmetry. The theoretical maximum bound on the lightest neutralino mass is much smaller than that of the Minimal Supersymmetric Standard Model (MSSM) because of the mixing pattern of the extra components. In a U(1)' model where the U(1)' symmetry is broken by a secluded sector (the S-model), tan\\beta is required to be < 3 to have realistic electroweak symmetry breaking. These facts suggest that the a_\\mu prediction may be meaningfully different from that of the MSSM. We evaluate and compare the muon anomalous magnetic moment in this model and the MSSM and discuss the constraints on tan\\beta and relevant soft breaking terms. There are regions of the parameter space that can explain the experimental deviation of a_\\mu from the Standard Model calculation and yield an accept...
N= 4 Supersymmetric Quantum Mechanical Model: Novel Symmetries
Krishna, S
2016-01-01
We discuss a set of novel discrete symmetry transformations of the N = 4 supersymmetric quantum mechanical model of a charged particle moving on a sphere in the background of Dirac magnetic monopole. The usual five continuous symmetries (and their conserved Noether charges) and two discrete symmetries together provide the physical realizations of the de Rham cohomological operators of differential geometry. We have also exploited the supervariable approach to derive the nilpotent N = 4 SUSY transformations and provided the geometrical interpretation in the language of translational generators along the Grassmannian directions onto (1, 4)-dimensional supermanifold.
𝒩 = 4 supersymmetric quantum mechanical model: Novel symmetries
Krishna, S.
2017-04-01
We discuss a set of novel discrete symmetry transformations of the 𝒩 = 4 supersymmetric quantum mechanical model of a charged particle moving on a sphere in the background of Dirac magnetic monopole. The usual five continuous symmetries (and their conserved Noether charges) and two discrete symmetries together provide the physical realizations of the de Rham cohomological operators of differential geometry. We have also exploited the supervariable approach to derive the nilpotent 𝒩 = 4 SUSY transformations and provided the geometrical interpretation in the language of translational generators along the Grassmannian directions 𝜃α and 𝜃¯α onto (1, 4)-dimensional supermanifold.
Spontaneous supersymmetry breaking on the lattice
Wenger, Urs [Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, University of Bern, Sidlerstrasse 5, CH-3012 Bern (Switzerland)
2013-07-01
We discuss various strategies for regularising supersymmetric quantum field theories on a space-time lattice. In general, simulations of lattice models with spontaneously broken supersymmetry suffer from a fermion sign problem related to the vanishing of the Witten index. We discuss a novel approach which evades this problem in low dimensions by formulating the path integral on the lattice in terms of fermion loops. Then we present exact results on the spectrum and the Witten index for N=2 supersymmetric quantum mechanics and results from simulations of the spontaneously broken N=1 Wess-Zumino model.
No-scale supergravity realization of the Starobinsky model of inflation.
Ellis, John; Nanopoulos, Dimitri V; Olive, Keith A
2013-09-13
We present a model for cosmological inflation based on a no-scale supergravity sector with an SU(2,1)/SU(2)×U(1) Kähler potential, a single modulus T, and an inflaton superfield Φ described by a Wess-Zumino model with superpotential parameters (μ, λ). When T is fixed, this model yields a scalar spectral index n(s) and a tensor-to-scalar ratio r that are compatible with the Planck measurements for values of λ≃μ/3M(P). For the specific choice λ=μ/3M(P), the model is a no-scale supergravity realization of the R+R2 Starobinsky model.
Dark matter candidates in the constrained exceptional supersymmetric standard model
Athron, P.; Thomas, A. W.; Underwood, S. J.; White, M. J.
2017-02-01
The exceptional supersymmetric standard model is a low energy alternative to the minimal supersymmetric standard model (MSSM) with an extra U (1 ) gauge symmetry and three generations of matter filling complete 27-plet representations of E6. This provides both new D and F term contributions that raise the Higgs mass at tree level, and a compelling solution to the μ -problem of the MSSM by forbidding such a term with the extra U (1 ) symmetry. Instead, an effective μ -term is generated from the vacuum expectation value of an SM singlet which breaks the extra U (1 ) symmetry at low energies, giving rise to a massive Z'. We explore the phenomenology of the constrained version of this model in substantially more detail than has been carried out previously, performing a ten dimensional scan that reveals a large volume of viable parameter space. We classify the different mechanisms for generating the measured relic density of dark matter found in the scan, including the identification of a new mechanism involving mixed bino/inert-Higgsino dark matter. We show which mechanisms can evade the latest direct detection limits from the LUX 2016 experiment. Finally we present benchmarks consistent with all the experimental constraints and which could be discovered with the XENON1T experiment.
Elias, V; Miransky, V A; Shovkovy, I A
1996-01-01
The infrared dynamics in the (3+1)--dimensional supersymmetric and non--supersymmetric Nambu--Jona--Lasinio model in a constant magnetic field is studied. It is shown that while at strong coupling the dynamics in these two models is essentially different, the models become equivalent at weak coupling. In particular, at weak coupling, as the strength of the magnetic field goes to infinity, both the supersymmetric and non--supersymmetric Nambu--Jona--Lasinio models with N_c colors become equivalent to the (1+1)--dimensional Gross-Neveu model with the number of colors \\tilde{N}_c=N_c|eB|S/2\\pi, where S is the area in the plane perpendicular to the magnetic field {\\bf B}. The relevance of these results for cosmological models based on superymmetric dynamics is pointed out.
A completely invariant SUSY transform of supersymmetric QED
Walker, M L [College of Natural Sciences and Department of Applied Physics, Kyung Hee University, Yong-In, KyongGi, 449-701 (Korea, Republic of)
2004-09-01
We study the SUSY breaking of the covariant gauge-fixing term in SUSY QED and consider its correspondence to a breaking of the Lorentz gauge condition by SUSY. Reasoning by analogy with SUSY's violation of the Wess-Zumino gauge, we argue that the SUSY transformation, already modified to preserve the Wess-Zumino gauge, should be further modified by another gauge transformation which restores the Lorentz gauge condition. We derive this modification and use the resulting transformation to derive a Ward identity relating the photon and photino propagators without using ghost fields. Our transformation also fulfils the SUSY algebra, modulo terms that vanish in the Lorentz gauge. We finish with a discussion of how to circumvent our transform's non-local, non-linear nature when deriving higher-order Green's function Ward identities.
A completely invariant SUSY transform of supersymmetric QED
Walker, M. L.
2004-09-01
We study the SUSY breaking of the covariant gauge-fixing term in SUSY QED and consider its correspondence to a breaking of the Lorentz gauge condition by SUSY. Reasoning by analogy with SUSY's violation of the Wess-Zumino gauge, we argue that the SUSY transformation, already modified to preserve the Wess-Zumino gauge, should be further modified by another gauge transformation which restores the Lorentz gauge condition. We derive this modification and use the resulting transformation to derive a Ward identity relating the photon and photino propagators without using ghost fields. Our transformation also fulfils the SUSY algebra, modulo terms that vanish in the Lorentz gauge. We finish with a discussion of how to circumvent our transform's non-local, non-linear nature when deriving higher-order Green's function Ward identities.
Theory and Phenomenology of an Exceptional Supersymmetric Standard Model
King, S F; Nevzorov, R
2006-01-01
We make a comprehensive study of the theory and phenomenology of a low energy supersymmetric standard model originating from a string-inspired $E_6$ grand unified gauge group. The Exceptional Supersymmetric Standard Model (ESSM) considered here is based on the low energy SM gauge group together with an extra $Z'$ corresponding to an extra $U(1)_{N}$ gauge symmetry under which right--handed neutrinos have zero charge. The low energy matter content of the ESSM corresponds to three 27 representations of the $E_6$ symmetry group, to ensure anomaly cancellation, plus an additional pair of Higgs--like doublets as required for high energy gauge coupling unification. The ESSM is therefore a low energy alternative to the MSSM or NMSSM. The ESSM involves extra matter beyond the MSSM contained in three $5+5^*$ representations of SU(5), plus three SU(5) singlets which carry $U(1)_{N}$ charges, one of which develops a VEV, providing the effective $\\mu$ term for the Higgs doublets, as well as the necessary exotic fermion m...
Matrix Models, Topological Strings, and Supersymmetric Gauge Theories
Dijkgraaf, R; Dijkgraaf, Robbert; Vafa, Cumrun
2002-01-01
We show that B-model topological strings on local Calabi-Yau threefolds are large N duals of matrix models, which in the planar limit naturally give rise to special geometry. These matrix models directly compute F-terms in an associated N=1 supersymmetric gauge theory, obtained by deforming N=2 theories by a superpotential term that can be directly identified with the potential of the matrix model. Moreover by tuning some of the parameters of the geometry in a double scaling limit we recover (p,q) conformal minimal models coupled to 2d gravity, thereby relating non-critical string theories to type II superstrings on Calabi-Yau backgrounds.
Matrix models, topological strings, and supersymmetric gauge theories
Dijkgraaf, Robbert E-mail: rhd@science.uva.nl; Vafa, Cumrun
2002-11-11
We show that B-model topological strings on local Calabi-Yau threefolds are large-N duals of matrix models, which in the planar limit naturally give rise to special geometry. These matrix models directly compute F-terms in an associated N=1 supersymmetric gauge theory, obtained by deforming N=2 theories by a superpotential term that can be directly identified with the potential of the matrix model. Moreover by tuning some of the parameters of the geometry in a double scaling limit we recover (p,q) conformal minimal models coupled to 2d gravity, thereby relating non-critical string theories to type II superstrings on Calabi-Yau backgrounds.
Making Supersymmetric Quivers from N =(0,2) Sigma Models
Shifman, Mikhail; Yung, Alexei
2014-01-01
We show how to construct quiver-like (0,2) sigma models starting from n copies of (2,2) CP(N-1) models (or similar more generic models). These "quivers" present a natural generalization of the non-minimally deformed (2,2) model with an extra (0,2) fermion superfield on tangle bundle T[CP(N-1)xC^1] considered previously. A remarkable feature observed is elimination of the spontaneous supersymmetry breaking. We study supersymmetric vacua and determine the particle spectrum in the large-N limit. We then examine the \\beta -functions of our quiver-like (0,2) sigma models and show that under certain conditions they develop an infrared fixed point in the perturbative domain.
Investigating multiple solutions in the constrained minimal supersymmetric standard model
Allanach, B.C. [DAMTP, CMS, University of Cambridge,Wilberforce Road, Cambridge, CB3 0HA (United Kingdom); George, Damien P. [DAMTP, CMS, University of Cambridge,Wilberforce Road, Cambridge, CB3 0HA (United Kingdom); Cavendish Laboratory, University of Cambridge,JJ Thomson Avenue, Cambridge, CB3 0HE (United Kingdom); Nachman, Benjamin [SLAC, Stanford University,2575 Sand Hill Rd, Menlo Park, CA 94025 (United States)
2014-02-07
Recent work has shown that the Constrained Minimal Supersymmetric Standard Model (CMSSM) can possess several distinct solutions for certain values of its parameters. The extra solutions were not previously found by public supersymmetric spectrum generators because fixed point iteration (the algorithm used by the generators) is unstable in the neighbourhood of these solutions. The existence of the additional solutions calls into question the robustness of exclusion limits derived from collider experiments and cosmological observations upon the CMSSM, because limits were only placed on one of the solutions. Here, we map the CMSSM by exploring its multi-dimensional parameter space using the shooting method, which is not subject to the stability issues which can plague fixed point iteration. We are able to find multiple solutions where in all previous literature only one was found. The multiple solutions are of two distinct classes. One class, close to the border of bad electroweak symmetry breaking, is disfavoured by LEP2 searches for neutralinos and charginos. The other class has sparticles that are heavy enough to evade the LEP2 bounds. Chargino masses may differ by up to around 10% between the different solutions, whereas other sparticle masses differ at the sub-percent level. The prediction for the dark matter relic density can vary by a hundred percent or more between the different solutions, so analyses employing the dark matter constraint are incomplete without their inclusion.
New aspects of flavour model building in supersymmetric grand unification
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
A Supersymmetric Composite Model with Dynamical Supersymmetry Breaking
Kitazawa, N; Kitazawa, Noriaki; Okada, Nobuchika
1997-01-01
We present a supersymmetric composite model with dynamical supersymmetry breaking. The model is based on the gauge group $SU(2)_S \\times SU(2)_H \\times SU(3)_c \\times SU(2)_L \\times U(1)_Y$. Supersymmetry is dynamically broken by the non-perturbative effect of the $SU(2)_S$ `supercolor' interaction. The large top Yukawa coupling is naturally generated by the $SU(2)_H$ `hypercolor' interaction as recently proposed by Nelson and Strassler. The supersymmetry breaking is mediated to the standard model sector by a new mechanism. The electroweak symmetry breaking is caused by the radiative correction due to the large top Yukawa coupling with the supersymmetry breaking. This is the `radiative breaking scenario', which originates from the dynamics of the supercolor and hypercolor gauge interactions.
Leptonic {ital CP} violation in the supersymmetric standard model
Joshipura, A.S.; Nowakowski, M. [Theory Group, Physical Research Laboratory, Navrangpura, Ahmedabad 380 009 (India)
1995-05-01
We point out the possibility of spontaneous and hard {ital CP} violation in the scalar potential of the {ital R}-parity broken supersymmetric standard model. The existence of spontaneous {ital CP} violation depends crucially on the {ital R}-parity-breaking terms in the superpotential and, in addition, on the choice of the soft supersymmetry-breaking terms. Unlike in theories with {ital R}-parity conservation, it is natural, in the context of the present model, for the sneutrinos to acquire (complex) vacuum expectation values. In the context of this model we examine here the global implications, such as the strength of the {ital CP}-violating interactions and the neutrino masses.
Nucleon Electric Dipole Moments in High-Scale Supersymmetric Models
Hisano, Junji; Kuramoto, Wataru; Kuwahara, Takumi
2015-01-01
The electric dipole moments (EDMs) of electron and nucleons are the promising probe of the new physics. In the generic high-scale supersymmetric (SUSY) scenarios such as models based on mixture of the anomaly and gauge mediations, gluino has an additional contribution to the nucleon EDMs. In this paper, we estimated the effect of the CP-violating gluon Weinberg operator induced by the gluino chromoelectric dipole moment in the high-scale SUSY scenarios, and we evaluated the nucleon and electron EDMs in these scenarios. We found that in the generic high-scale SUSY models, the nucleon EDMs may receive the sizable contribution from the Weinberg operator. Thus, it is important to compare the nucleon EDMs with the electron EDM in order to discriminate among the high-scale SUSY models.
Nucleon electric dipole moments in high-scale supersymmetric models
Hisano, Junji; Kobayashi, Daiki; Kuramoto, Wataru; Kuwahara, Takumi
2015-11-01
The electric dipole moments (EDMs) of electron and nucleons are promising probes of the new physics. In generic high-scale supersymmetric (SUSY) scenarios such as models based on mixture of the anomaly and gauge mediations, gluino has an additional contribution to the nucleon EDMs. In this paper, we studied the effect of the CP -violating gluon Weinberg operator induced by the gluino chromoelectric dipole moment in the high-scale SUSY scenarios, and we evaluated the nucleon and electron EDMs in the scenarios. We found that in the generic high-scale SUSY models, the nucleon EDMs may receive the sizable contribution from the Weinberg operator. Thus, it is important to compare the nucleon EDMs with the electron one in order to discriminate among the high-scale SUSY models.
Das, Debottam; Ellwanger, Ulrich; Teixeira, Ana M.
2012-03-01
The code NMSDECAY allows to compute widths and branching ratios of sparticle decays in the Next-to-Minimal Supersymmetric Standard Model. It is based on a generalization of SDECAY, to include the extended Higgs and neutralino sectors of the NMSSM. Slepton 3-body decays, possibly relevant in the case of a singlino-like lightest supersymmetric particle, have been added. NMSDECAY will be part of the NMSSMTools package, which computes Higgs, sparticle masses and Higgs decays in the NMSSM. Program summaryProgram title: NMSDECAY Catalogue identifier: AELC_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AELC_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 188 177 No. of bytes in distributed program, including test data, etc.: 1 896 478 Distribution format: tar.gz Programming language: FORTRAN77 Computer: All supporting g77, gfortran, ifort Operating system: All supporting g77, gfortran, ifort Classification: 11.1 External routines: Routines in the NMSSMTools package: At least one of the routines in the directory main (e.g. nmhdecay.f), all routines in the directory sources. (All software is included in the distribution package.) Nature of problem: Calculation of all decay widths and decay branching fractions of all particles in the Next-to-Minimal Supersymmetric Standard Model. Solution method: Suitable generalization of the code SDECAY [1] including the extended Higgs and neutralino sector of the Next-to-Minimal Supersymmetric Standard Model, and slepton 3-body decays. Additional comments: NMSDECAY is interfaced with NMSSMTools, available on the web page http://www.th.u-psud.fr/NMHDECAY/nmssmtools.html. Running time: On an Intel Core i7 with 2.8 GHZ: about 2 seconds per point in parameter space, if all flags flagqcd, flagmulti and flagloop are switched on.
Neutron electric dipole moment in the minimal supersymmetric standard model
Inui, T; Sakai, N; Sasaki, T; Inui, T; Mumura, Y; Sakai, N; Sasaki, T
1995-01-01
Neutron electric dipole moment (EDM) due to single quark EDM and to the transition EDM is calculated in the minimal supersymmetric standard model. Assuming that the Cabibbo-Kobayashi-Maskawa matrix at the grand unification scale is the only source of CP violation, complex phases are induced in parameters of soft supersymmetry breaking at low energies. Chargino one-loop diagram is found to give the dominant contribution of the order of 10^{-27}\\sim 10^{-29}\\:e\\cdotcm for quark EDM, assuming the light chargino mass and the universal scalar mass to be 50 GeV and 100 GeV, respectively. Therefore the neutron EDM in this class of model is difficult to measure experimentally. Gluino one-loop diagram also contributes due to the flavor changing gluino coupling. The transition EDM is found to give dominant contributions for certain parameter regions.
Anatomy of Higgs mass in supersymmetric inverse seesaw models
Chun, Eung Jin, E-mail: ejchun@kias.re.kr [Korea Institute for Advanced Study, Seoul 130-722 (Korea, Republic of); Mummidi, V. Suryanarayana, E-mail: soori9@cts.iisc.ernet.in [Centre for High Energy Physics, Indian Institute of Science, Bangalore 560012 (India); Vempati, Sudhir K., E-mail: vempati@cts.iisc.ernet.in [Centre for High Energy Physics, Indian Institute of Science, Bangalore 560012 (India)
2014-09-07
We compute the one loop corrections to the CP-even Higgs mass matrix in the supersymmetric inverse seesaw model to single out the different cases where the radiative corrections from the neutrino sector could become important. It is found that there could be a significant enhancement in the Higgs mass even for Dirac neutrino masses of O(30) GeV if the left-handed sneutrino soft mass is comparable or larger than the right-handed neutrino mass. In the case where right-handed neutrino masses are significantly larger than the supersymmetry breaking scale, the corrections can utmost account to an upward shift of 3 GeV. For very heavy multi TeV sneutrinos, the corrections replicate the stop corrections at 1-loop. We further show that general gauge mediation with inverse seesaw model naturally accommodates a 125 GeV Higgs with TeV scale stops.
An Interacting N = 2 Supersymmetric Quantum Mechanical Model: Novel Symmetries
Krishna, S; Malik, R P
2015-01-01
We demonstrate the existence of a set of novel discrete symmetry transformations in the case of an interacting N = 2 supersymmetric quantum mechanical model of a system of an electron moving on a sphere in the background of a magnetic monopole and establish its interpretation in the language of differential geometry. These discrete symmetries are, over and above, the usual three continuous symmetries of the theory which together provide the physical realization of the de Rham cohomological operators of differential geometry. We derive the nilpotent N = 2 SUSY transformations by exploiting our idea of supervariable approach and provide geometrical meaning to these transformations in the language of Grassmannian translational generators on a (1, 2)-dimensional supermanifold on which our N = 2 SUSY quantum mechanical model is generalized. We express the conserved supercharges and the invariance of the Lagrangian in terms of the supervariables, obtained after the imposition of the SUSY invariant restrictions, and...
Radiative decays of light vector mesons in a quark level linear sigma model
Napsuciale, M; Alvarado-Anell, E
2003-01-01
We calculate the P0 to gamma gamma, V0 to P0 gamma and V0to V'0 gamma gamma decays in the framework of a U(3)xU(3) linear sigma model which includes constituent quarks. For the first two decays this approach improves results based on the anomalous Wess-Zumino term, with contributions due to SU(3) symmetry breaking and vector mixing. The phi to (omega,rho) gamma gamma decays are dominated by resonant eta' exchange . Our calculation for the later decays improves and update similar calculations in the -closely related- framework of vector meson dominance. We obtain BR(phi to rho gamma gamma)=2.5x10^{-5} and BR(phi to omega gamma gamma)=2.8x10^{-6} within the scope of the high-luminosity phi factories.
Rahaman, Anisur
2016-01-01
The generalized version of a lower dimensional model where vector and axial vector interaction get mixed up with different weight is considered. The bosonized version of which does not posses the local gauge symmetry. An attempt has been made here to construct BRST invariant reformulation of this model using Batalin Fradlin and Vilkovisky formalism. It is found that the extra field needed to make it gauge invariant turns into Wess-Zumino scalar with appropriate choice of gauge fixing. An application of finite field dependent BRST and anti-BRST transformation is also made here in order to show the transmutation between the BRST symmetric and the usual non-symmetric version of the model.
The unified minimal supersymmetric model with large Yukawa couplings
Rattazzi, Riccardo
1996-01-01
The consequences of assuming the third-generation Yukawa couplings are all large and comparable are studied in the context of the minimal supersymmetric extension of the standard model. General aspects of the RG evolution of the parameters, theoretical constraints needed to ensure proper electroweak symmetry breaking, and experimental and cosmological bounds on low-energy parameters are presented. We also present complete and exact semi-analytic solutions to the 1-loop RG equations. Focusing on SU(5) or SO(10) unification, we analyze the relationship between the top and bottom masses and the superspectrum, and the phenomenological implications of the GUT conditions on scalar masses. Future experimental measurements of the superspectrum and of the strong coupling will distinguish between various GUT-scale scenarios. And if present experimental knowledge is to be accounted for most naturally, a particular set of predictions is singled out.
Perturbative unification of gauge couplings in supersymmetric E6 models
Cho, Gi-Chol; Maru, Nobuhito; Yotsutani, Kaho
2016-07-01
We study gauge coupling unification in supersymmetric (SUSY) E6 models where an additional U(1)‧ gauge symmetry is broken near the TeV scale and a number of exotic matter fields from the 27 representations have O(TeV) mass. Solving the two-loop renormalization group equations (RGE) of gauge couplings and a kinetic mixing coupling between the U(1)‧ and U(1)Y gauge fields, we find that the gauge couplings fall into the non-perturbative regime below the grand unified theories (GUT) scale. We examine threshold corrections on the running of gauge couplings from both light and heavy ( ˜ GUT scale) particles and show constraints on the size of corrections to achieve the perturbative unification of gauge couplings.
Supersymmetric models with tan$\\beta$ close to unity
Ananthanarayan, B; Shafi, Qaisar
1994-01-01
Within the framework of supersymmetric grand unification, estimates of the $b$ quark mass based on the asymptotic relation $m_b \\simeq m_\\tau$ single out the region with $\\tan\\beta$ close to unity, particularly if $m_t(m_t) \\stackrel{_<}{_\\sim} 170\\ GeV$. We explore the radiative breaking of the electroweak symmetry and the associated sparticle and higgs spectroscopy in models with $1 < \\tan\\beta \\stackrel{_<}{_\\sim} 1.6$. The lightest scalar higgs is expected to have a mass below $100\\ GeV$, while the remaining four higgs masses exceed $300\\ GeV$. The lower bounds on some of the sparticle masses are within the range of LEP 200.
R-Parity Conserving Supersymmetric Extension of the Zee Model
Kanemura, Shinya; Sugiyama, Hiroaki
2015-01-01
We extend the Zee model, where tiny neutrino masses are generated at the one loop level, to a supersymmetric model with R-parity conservation. It is found that the neutrino mass matrix can be consistent with the neutrino oscillation data thanks to the nonholomorphic Yukawa interaction generated via one-loop diagrams of sleptons. We find a parameter set of the model, where in addition to the neutrino oscillation data, experimental constraints from the lepton flavor violating decays of charged leptons and current LHC data are also satisfied. In the parameter set, an additional CP-even neutral Higgs boson other than the standard-model-like one, a CP-odd neutral Higgs boson, and two charged scalar bosons are light enough to be produced at the LHC and future lepton colliders. If the lightest charged scalar bosons are mainly composed of the SU(2)_L-singlet scalar boson in the model, they would decay into e nu and mu nu with 50% of a branching ratio for each. In such a case, the relation among the masses of the char...
TeV-scale supersymmetric standard model and brane world
Kakushadze, Zurab E-mail: zurab@string.harvard.edu
1999-07-12
Recently we proposed a TeV-scale Supersymmetric Standard Model in which the gauge coupling unification is as precise (at one loop) as in the MSSM, and occurs in the TeV range. One of the key ingredients of this model is the presence of new states neutral under SU(3){sub c}xSU(2){sub w} but charged under U(1){sub Y} whose mass scale is around that of the electroweak Higgs doublets. In this paper we show that the introduction of these states allows us to gauge novel anomaly free discrete (as well as continuous) symmetries (similar to 'lepton' and 'baryon' numbers) which suppress dangerous higher dimensional operators and stabilize the proton. Furthermore, the mass hierarchy between the up and down quarks (e.g. t versus b) can be explained without appealing to large tan {beta}, and the {mu}-term for the electroweak Higgs doublets (as well as for the new states) can be generated. We also discuss various phenomenological implications of our model which lead to predictions testable in the present or near future collider experiments. In particular, we point out that signatures of scenarios with high versus low unification (string) scale might be rather different. This suggests the possibility that the collider experiments may distinguish between these scenarios even without a direct production of heavy Kaluza-Klein or string states.
Dark matter candidates in the constrained Exceptional Supersymmetric Standard Model
Athron, P; Underwood, S J; White, M J
2016-01-01
The Exceptional Supersymmetric Standard Model (E$_6$SSM) is a low energy alternative to the MSSM with an extra $U(1)$ gauge symmetry and three generations of matter filling complete 27-plet representations of $E_6$. This provides both new D and F term contributions that raise the Higgs mass at tree level, and a compelling solution to the $\\mu$-problem of the MSSM by forbidding such a term with the extra $U(1)$ symmetry. Instead, an effective $\\mu$-term is generated from the VEV of an SM singlet which breaks the extra $U(1)$ symmetry at low energies, giving rise to a massive $Z^\\prime$. We explore the phenomenology of the constrained version of this model (cE$_6$SSM) in substantially more detail than has been carried out previously, performing a ten dimensional scan that reveals a large volume of viable parameter space. We classify the different mechanisms for generating the measured relic density of dark matter found in the scan, including the identification of a new mechanism involving mixed bino/inert-Higgs...
Probes of Yukawa unification in supersymmetric SO(10) models
Westhoff, Susanne
2009-10-23
This work is composed as follows: In Chapter 1, the disposed reader is made familiar with the foundations of flavourphysics and Grand Unification, including group-theoretical aspects of SO(10). In Chapter 2, we introduce a specific supersymmetric GUT model based on SO(10) and designed to probe down-quark-lepton Yukawa unification. Within this framework we explore the effects of large atmospheric neutrino mixing in bottom-strange transitions on the mass difference and CP phase in B{sub s}- anti B{sub s} meson mixing. Chapter 3 is devoted to corrections to Yukawa unification. We derive constraints on Yukawa corrections for light fermions from K- anti K and B{sub d}- anti B {sub d} mixing. As an application we study implications of neutrino mixing effects in CP-violating K and B{sub d} observables on the unitrity triangle. Finally, in Chapter 4, we discuss effects of large tan {beta} in B{yields}(D){tau}{nu} decays with respect to their potential to discover charged Higgs bosons and to discriminate between different GUT models of flavour.
Lepton flavor violation in supersymmetric low-scale seesaw models
Popov, Luka
2013-01-01
The minimal supersymmetric standard model with a low scale see-saw mechanism is presented. Within this framework, the lepton flavour violation in the charged lepton sector is thoroughly studied. Special attention is paid to the individual loop contributions due to the heavy neutrinos $N_{1,2,3}$, sneutrinos $\\tilde{N}_{1,2,3}$ and soft SUSY-breaking terms. For the first time, the complete set of box diagrams is included, in addition to the photon and $Z$-boson mediated interactions. The complete set of chiral amplitudes and their associate form-factors related to the neutrinoless three-body charged lepton flavor violating decays of the muon and tau, such as $\\mu \\to eee$, $\\tau \\to \\mu\\mu\\mu$, $\\tau \\to e\\mu\\mu$ and $\\tau \\to ee\\mu$, as well as the coherent $\\mu \\to e$ conversion in nuclei, were derived. The obtained analytical results are general and can be applied to most of the New Physics models with charged lepton flavor violation. This systematic analysis has revealed the existence of two new box form f...
Ilinskii, K N; Melezhik, V S; Ilinski, K N; Kalinin, G V; Melezhik, V V
1994-01-01
We revise the sequences of SUSY for a cyclic adiabatic evolution governed by the supersymmetric quantum mechanical Hamiltonian. The condition (supersymmetric adiabatic evolution) under which the supersymmetric reductions of Berry (nondegenerated case) or Wilczek-Zee (degenerated case) phases of superpartners are taking place is pointed out. The analogue of Witten index (supersymmetric Berry index) is determined. As the examples of suggested concept of supersymmetric adiabatic evolution the Holomorphic quantum mechanics on complex plane and Meromorphic quantum mechanics on Riemann surface are considered. The supersymmetric Berry indexes for the models are calculated.
WIEDEMANN, A; MULLERKIRSTEN, HJW
1993-01-01
Considering the N = 1 supersymmetry transformations of supersymmetric nonlinear sigma models in 1 + 1 dimensions we construct explicitly conserved Noether currents associated with supersymmetry transformations and derive the associated conserved charges in terms of the basic fields. We compare this
BETHE ANSATZ FOR SUPERSYMMETRIC MODEL WITH?Uq[osp( 1｜2 ) ] SYMMETRY
杨文力
2001-01-01
Using the algebraic Bethe ansatz method, we obtain the eigenvalues of the transfer matrix of the supersymmetric model with Uq[osp(1｜2)] symmetry under periodic boundary and twisted boundary conditions.
Solving Two Kinds of JC Models Relating to Two-Photon Process by Supersymmetric Transformation
FAN Hong-Yi; Wei-Jun
2004-01-01
We propose two kinds of new Jaynes Cummings models relating to two-photon process by using the supersymmetric unitary transformation. The corresponding energy eigenvalues and eigenvectors are obtained.
Tomino, Dan
2010-01-01
1-loop vacuum energies of (fuzzy) spacetimes from a supersymmetric reduced model with Filippov 3-algebra are discussed. A_{2,2} algebra, Nambu-Poisson algebra in flat spacetime, and a Lorentzian 3-algebra are examined as 3-algebras.
Comments on Noncommutative Superspace
Terashima, S; Terashima, Seiji; Yee, Jung-Tay
2003-01-01
We study the N=1/2 supersymmetric theory on noncommutative superspace found by Seiberg which is a deformation of usual superspace. We consider deformed Wess-Zumino model as an example and shows vanishing of vacuum energy, renormalization of superpotential and nonvanishing of tadpole. We find that the perturbative effective action has terms which are not written in the star deformation. Also we consider gauge theory on noncommutative superspace and observe that gauge group is restricted. We generalize the star deformation to include noncommutativity between bosonic coordinates and fermionic coordinates.
Supersymmetry in anti-de Sitter space
Burges, C.J.C.; Freedman, D.Z.; Davis, S.; Gibbons, G.W.
1986-04-01
We consider the Wess-Zumino model in a background anti-de Sitter space-time in four dimensions (AdS)/sub 4/. We show that the naive generators of the O(3,2) isometry group, obtained by the Noether method, must be improved by adding surface terms. The improved generators have a manifestly positive definite energy density, are conserved, and have vanishing expectation value in a supersymmetric vacuum. The naive generators enjoy none of these properties. Propagators for scalar and spinor fields in (Ad S)/sub 4/ are presented, and a simple derivation of the trace anomaly is given.
New Constraints from Electric Dipole Moments on Parameters of the Supersymmetric SO(10) Model
Khriplovich, I. B.; Zyablyuk, K. N.
1996-01-01
We calculate the chromoelectric dipole moment (CEDM) of d- and s-quark in the supersymmetric SO(10) model. CEDM is more efficient than quark electric dipole moment (EDM), in inducing the neutron EDM. New, strict constraints on parameters of the supersymmetric SO(10) model follow in this way from the neutron dipole moment experiments. As strict bounds are derived from the upper limits on the dipole moment of odd isotope of mercury.
Neutralino mass bounds in the next-to-minimal supersymmetric standard model
Franke, F; Bartl, Alfred
1994-01-01
We analyze the experimental data from the search for new particles at LEP 100 and obtain mass bounds for the neutralinos of the Next--To--Minimal Supersymmetric Standard Model (NMSSM). We find that for \\tan\\beta \\gsim 5.5 a massless neutralino is still possible, while the lower mass bound for the second lightest neutralino corresponds approximately to that for the lightest neutralino in the Minimal Supersymmetric Standard Model (MSSM).
Spin Measurements in Supersymmetric Models at the LHC
Lester, C G; The ATLAS collaboration
2009-01-01
I have been asked to talk about the prospects for Spin measurements at the LHC in relation to supersymmetric models. Post 2005 (i.e. post PHYS-2004-017 and ATL-PHYS-PUB-2005-023), the only such ATLAS work with PUB approval is ATL-PHYS-PUB-2007-004. As such, I am taking a very broad remit with this talk - and will mainly be talking about the above three works, and putting them in the context of prospective ideas for spin measurements at LHC experiments in general. My aims are to (1) to EDUCATE (to describe the sorts of methods that have been proposed both within ATLAS and outside to measure spins at the LHC) and (2) to INFORM the audience as to what has already been done in ATLAS. I will give due emphasis and credit to the works (PHYS-2004-017, ATL-PHYS-PUB-2005-023 and ATL-PHYS-PUB-2007-004).
Flat manifold leptogenesis in the supersymmetric standard model
Senami, M; Senami, Masato; Yamamoto, Katsuji
2002-01-01
Flat manifold leptogenesis a la Affleck-Dine is investigated with the slepton and Higgs fields, L, H_u, H_d, in the supersymmetric standard model. The multi-dimensional motion of these scalar fields is realized in the case that the L H_u and H_u H_d directions are comparably flat with the relevant non-renormalizable superpotential terms. Soon after the inflation, the lepton number asymmetry appears to fluctuate due to this multi-dimensional motion involving certain CP violating phases. Then, it is fixed to some significant non-zero value for the successful baryogenesis when the scalar fields begin to oscillate with rotating phases driven by the quartic coupling from the superpotential term h_e L H_d e^c with h_e \\sim 10^-5 - 10^-3. The Hubble parameter H_osc at this epoch for the completion of leptogenesis is much larger than the gravitino mass m_3/2 \\sim 10^3 GeV. The thermal terms may even play a cooperative role in this scenario of early leptogenesis. The lightest neutrino mass can be 10^-4 eV, if the rehe...
On Newton's law in supersymmetric braneworld models
Palma, G.A.
2007-05-15
We study the propagation of gravitons within 5-D supersymmetric braneworld models with a bulk scalar field. The setup considered here consists of a 5-D bulk spacetime bounded by two 4-D branes localized at the fixed points of an S{sup 1}/Z{sub 2} orbifold. There is a scalar field {phi} in the bulk which, provided a superpotential W({phi}), determines the warped geometry of the 5-D spacetime. This type of scenario is common in string theory, where the bulk scalar field {phi} is related to the volume of small compact extra dimensions. We show that, after the moduli are stabilized by supersymmetry breaking terms localized on the branes, the only relevant degrees of freedom in the bulk consist of a 5-D massive spectrum of gravitons. Then we analyze the gravitational interaction between massive bodies localized at the positive tension brane mediated by these bulk gravitons. It is shown that the Newtonian potential describing this interaction picks up a non-trivial contribution at short distances that depends on the shape of the superpotential W({phi}). We compute this contribution for dilatonic braneworld scenarios W({phi})=e{sup {alpha}}{sup {phi}} (where {alpha} is a constant) and discuss the particular case of 5-D Heterotic M-theory: It is argued that a specific footprint at micron scales could be observable in the near future. (orig.)
Yukawa matrix unification in the Minimal Supersymmetric Standard Model
Iskrzyński, Mateusz
2015-01-01
In this dissertation, the Minimal Supersymmetric Standard Model (MSSM) is studied as a low-energy theory stemming from the $SU(5)$ Grand Unified Theory (GUT). We investigate the possibility of satisfying the minimal $SU(5)$ boundary condition $\\mathbf{Y}^d=\\mathbf{Y}^{e\\,T}$ for the full $3\\!\\times\\!3$ down-quark and lepton Yukawa matrices at the GUT scale within the $R$-parity conserving MSSM. We give numerical evidence in favour of the statement: There exist regions in the parameter space of the R-parity conserving MSSM for which the unification of the down-quark and lepton Yukawa matrices takes place, while the predicted values of flavour, electroweak and other collider observables are consistent with experimental constraints. Furthermore, we find evidence that the bottom-tau and strange-muon Yukawa unification is possible with a stable MSSM vacuum in the standard form. We investigate two separate scenarios of the soft supersymmetry breaking terms at the GUT scale. In the first one, it is assumed that the ...
Mixed axion/neutralino cold dark matter in supersymmetric models
Baer, Howard; Lessa, Andre; Rajagopalan, Shibi; Sreethawong, Warintorn, E-mail: baer@nhn.ou.edu, E-mail: lessa@nhn.ou.edu, E-mail: shibi@nhn.ou.edu, E-mail: wstan@nhn.ou.edu [Dept. of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States)
2011-06-01
We consider supersymmetric (SUSY) models wherein the strong CP problem is solved by the Peccei-Quinn (PQ) mechanism with a concommitant axion/axino supermultiplet. We examine R-parity conserving models where the neutralino is the lightest SUSY particle, so that a mixture of neutralinos and axions serve as cold dark matter (a Z-tilde {sub 1} CDM). The mixed a Z-tilde {sub 1} CDM scenario can match the measured dark matter abundance for SUSY models which typically give too low a value of the usual thermal neutralino abundance, such as models with wino-like or higgsino-like dark matter. The usual thermal neutralino abundance can be greatly enhanced by the decay of thermally-produced axinos (ã) to neutralinos, followed by neutralino re-annihilation at temperatures much lower than freeze-out. In this case, the relic density is usually neutralino dominated, and goes as ∼ (f{sub a}/N)/m{sub ã}{sup 3/2}. If axino decay occurs before neutralino freeze-out, then instead the neutralino abundance can be augmented by relic axions to match the measured abundance. Entropy production from late-time axino decays can diminish the axion abundance, but ultimately not the neutralino abundance. In a Z-tilde {sub 1} CDM models, it may be possible to detect both a WIMP and an axion as dark matter relics. We also discuss possible modifications of our results due to production and decay of saxions. In the appendices, we present expressions for the Hubble expansion rate and the axion and neutralino relic densities in radiation, matter and decaying-particle dominated universes.
Supersymmetric Lepton Flavour Violation in Low-Scale Seesaw Models
Ilakovac, Amon
2009-01-01
We study a new supersymmetric mechanism for lepton flavour violation in \\mu and \\tau decays and \\mu -> e conversion in nuclei, within a minimal extension of the MSSM with low-mass heavy singlet neutrinos and sneutrinos. We find that the decays \\mu -> e\\gamma$, \\tau -> e\\gamma and \\tau -> \\mu\\gamma are forbidden in the supersymmetric limit of the theory, whereas other processes, such as \\mu -> eee, \\mu -> e conversion, \\tau -> eee and \\tau -> e\\mu\\mu, are allowed and can be dramatically enhanced several orders of magnitude above the observable level by potentially large neutrino Yukawa coupling effects. The profound implications of supersymmetric lepton flavour violation for present and future experiments are discussed.
Super-Zeeman Embedding Models on N-Supersymmetric World-Lines
Doran, C F; Gates, S J Jr; Hübsch, T; Iga, K M; Landweber, G D
2008-01-01
We construct a model of an electrically charged magnetic dipole with arbitrary N-extended world-line supersymmetry, which exhibits a supersymmetric Zeeman effect. By including supersymmetric constraint terms, the ambient space of the dipole may be tailored into an algebraic variety, and the supersymmetry broken for almost all parameter values. The so exhibited obstruction to supersymmetry breaking refines the standard one, based on the Witten index alone.
Searching for beyond the minimal supersymmetric standard model at the laboratory and in the sky
Kim, Ju Min
2010-09-15
We study the collider signals as well as Dark Matter candidates in supersymmetric models. We show that the collider signatures from a supersymmetric Grand Unification model based on the SO(10) gauge group can be distinguishable from those from the (constrained) minimal supersymmetric Standard Model, even though they share some common features. The N=2 supersymmetry has the characteristically distinct phenomenology, due to the Dirac nature of gauginos, as well as the extra adjoint scalars. We compute the cold Dark Matter relic density including a class of one-loop corrections. Finally, we discuss the detectability of neutralino Dark Matter candidate of the SO(10) model by the direct and indirect Dark Matter search experiments. (orig.)
Radiative Effects and Electroweak Symmetry Breaking in a Supersymmetric Preon Model
Kim, Jongbae
We construct the low energy effective theory of composite quarks, leptons, and Higgs bosons for a supersymmetric preon model and study the effects of renormalization-group based radiative corrections. The study on the evolution of scalar masses for avoiding color and charge breakings leads us to conclude that Yukawa couplings are bounded from above. The implementation of electroweak symmetry breaking requires that only the purely dynamical symmetry breaking should be needed for the model, but the combined scheme of dynamical and radiative symmetry breaking as well as the purely radiative symmetry breaking scheme be disfavored. Our analysis of (mb)/(m_τ ) including radiative effects shows that, should a discrepancy be found between the observed and the theoretical value of (mb)/(m_τ ) after experimental determination of supersymmetric particle masses, it would imply that the complete quark-lepton universality in the supersymmetric preon model does not hold either for the Yukawa couplings, or for the condensates, or for both.
Supersymmetric O(N) models in d=3 with functional renormalization group (FRG) methods
Hellwig, Tobias; Heilmann, Marianne; Wipf, Andreas [Theoretisch-Physikalisches Institut, Friedrich-Schiller-Universit Jena, Max-Wien-Platz 1, D-07743 Jena (Germany); Lithim, Daniel F. [Department of Physics and Astronomy, University of Sussex, BN1 9QH, Brighton (United Kingdom)
2013-07-01
While a lot of results concerning scalar O(N) models are known, much less is known for supersymmetric O(N) models. The 1/N expansions were examined in some earlier works with the help of the Hartree-Fock approximation. In this talk results for all N are presented. These results were obtained by using FRG methods and a manifest supersymmetric regulator. For finite N fixed point solutions and critical exponents are obtained. We comment on effects of different truncations in the effective average action. Starting point is the LPA approximation. In a second step a wave function renormalization is included and deviations from LPA solution are discussed. This is done for a field dependent and field independent form of the wave function renormalization. This knowledge could also prove to be helpful for further FRG studies of supersymmetric theories.
Matrix models from localization of five-dimensional supersymmetric noncommutative U(1) gauge theory
Lee, Bum-Hoon; Yang, Hyun Seok
2016-01-01
We study localization of five-dimensional supersymmetric $U(1)$ gauge theory on $\\mathbb{S}^3 \\times \\mathbb{R}_{\\theta}^{2}$ where $\\mathbb{R}_{\\theta}^{2}$ is a noncommutative (NC) plane. The theory can be isomorphically mapped to three-dimensional supersymmetric $U(N \\to \\infty)$ gauge theory on $\\mathbb{S}^3$ using the matrix representation on a separable Hilbert space on which NC fields linearly act. Therefore the NC space $\\mathbb{R}_{\\theta}^{2}$ allows for a flexible path to derive matrix models via localization from a higher-dimensional supersymmetric NC $U(1)$ gauge theory. The result shows a rich duality between NC $U(1)$ gauge theories and large $N$ matrix models in various dimensions.
Astrophysical aspects of fermion number violation in the supersymmetrical standard model
Manka, R
1993-01-01
The model of the supersymmetrical ball in the supersymmetrical standard model with additional global U(1) fermion symmetry is presented. We show that the supersymmetry breaking scale ( R-parity ), the global U(1) fermion symmetry scale and the electroweak symmetry breaking scale are strictly connected to each other. The realistic ball with $M \\sim 10^5 - 10^9 M_{\\odot} $ and the radius $ R \\sim 10^{12} - 10^{14} cm $ is obtained. Inside the ball all full symmetries are restored. The ball is stabilized by superpartners and right neutrinos which are massless inside.
Analysis of Leptogenesis in Supersymmetric Triplet Seesaw Model
Chun, E J
2007-01-01
We analyze leptogenesis in a supersymmetric triplet seesaw scenario that explains the observed neutrino masses, adopting a phenomenological approach where the decay branching ratios of the triplets and the amount of CP--violation in its different decay channels are assumed as free parameters. We find that the solutions of the relevant Boltzmann equations lead to a rich phenomenology, in particular much more complex compared to the non--supersymmetric case, mainly due to the presence of an additional Higgs doublet. Several unexpected and counter--intuitive behaviors emerge from our analysis: the amount of CP violation in one of the decay channels can prove to be be irrelevant to the final lepton asymmetry, leading to successful leptogenesis even in scenarios with a vanishing CP violation in the leptonic sector; gauge annihilations can be the dominant effect in the determination of the evolution of the triplet density up to very high values of its mass, leading anyway to a sizeable final lepton asymmetry, which...
Boundary Correlation Functions of the gl(1|1) Supersymmetric Vertex Model
ZHANG Chen-Jun; ZHOU Jian-Hua; YUE Rui-Hong
2008-01-01
The gl(1|1) supersymmetric vertex model with domain wall boundary conditions (DWBC) on an N×N square lattice is considered.We derive the reduction formulae for the one-point boundary correlation functions of the model.The determinant representation for the boundary correlation functions is also obtained.
Barranco, Alejandro
2012-01-01
We implement relativistic BCS superconductivity in N=1 supersymmetric field theories with a U(1)_R symmetry. The simplest model contains two chiral superfields with a Kahler potential modified by quartic terms. We study the phase diagram of the gap as a function of the temperature and the specific heat. The superconducting phase transition turns out to be first order, due to the scalar contribution to the one-loop potential. By virtue of supersymmetry, the critical curves depend logarithmically with the UV cutoff, rather than quadratically as in standard BCS theory. We comment on the difficulties in having fermion condensates when the chemical potential is instead coupled to a baryonic U(1)_B current. We also discuss supersymmetric models of BCS with canonical Kahler potential constructed by "integrating-in" chiral superfields.
Quinto, A. G.; Ferrari, A. F.; Lehum, A. C.
2016-06-01
In this work, we investigate the consequences of the Renormalization Group Equation (RGE) in the determination of the effective superpotential and the study of Dynamical Symmetry Breaking (DSB) in an N = 1 supersymmetric theory including an Abelian Chern-Simons superfield coupled to N scalar superfields in (2 + 1) dimensional spacetime. The classical Lagrangian presents scale invariance, which is broken by radiative corrections to the effective superpotential. We calculate the effective superpotential up to two-loops by using the RGE and the beta functions and anomalous dimensions known in the literature. We then show how the RGE can be used to improve this calculation, by summing up properly defined series of leading logs (LL), next-to-leading logs (NLL) contributions, and so on... We conclude that even if the RGE improvement procedure can indeed be applied in a supersymmetric model, the effects of the consideration of the RGE are not so dramatic as it happens in the non-supersymmetric case.
Critical behavior of supersymmetric O(N) models in the large-N limit
Litim, Daniel F; Synatschke-Czerwonka, Franziska; Wipf, Andreas
2011-01-01
We derive a supersymmetric renormalization group (RG) equation for the scale-dependent superpotential of the supersymmetric O(N) model in three dimensions. For a supersymmetric optimized regulator function we solve the RG equation for the superpotential exactly in the large-N limit. The fixed-point solutions are classified by an exactly marginal coupling. In the weakly coupled regime there exists a unique fixed point solution, for intermediate couplings we find two separate fixed point solutions and in the strong coupling regime no globally defined fixed-point potentials exist. We determine the exact critical exponents both for the superpotential and the associated scalar potential. Finally we relate the high-temperature limit of the four-dimensional theory to the Wilson-Fisher fixed point of the purely scalar theory.
Remark on the Consistent Gauge Anomaly in Supersymmetric Theories
Ohshima, Y; Suzuki, H; Yasuta, H; Ohshima, Yoshihisa; Okuyama, Kiyoshi; Suzuki, Hiroshi; Yasuta, Hirofumi
1999-01-01
We present a direct field theoretical calculation of the consistent gauge anomaly in the superfield formalism, on the basis of a definition of the effective action through the covariant gauge current. The scheme is conceptually and technically simple and the gauge covariance in intermediate steps reduces calculational labors considerably. The resultant superfield anomaly, being proportional to the anomaly $d^{abc}=\\tr T^a\\{T^b,T^c\\}$, is minimal even without supplementing any counterterms. Our anomaly coincides with the anomaly obtained by Marinkovi\\'c as the solution of the Wess-Zumino consistency condition.
The Boundary States of the q-Deformed Supersymmetric t-J Model with a Boundary
YANG Wen-Li; ZHEN Yi
2001-01-01
The q-deformed supersymmetric t J model on a semi-infinite lattice is diagonalized by using the level-one vertex operators of the quantum affine superalgebra Uq[sl(2|1)]. We give the bosonization of the boundary states.``
The Higgs Sector and CoGeNT/DAMA-Like Dark Matter in Supersymmetric Models
Gunnion, John F
2010-01-01
Recent data from CoGeNT and DAMA are roughly consistent with a very light dark matter particle with $m\\sim 4-10\\gev$ and spin-independent cross section of order $\\sigma_{SI} \\sim (1-3)\\times 10^{-4}\\pb$. An important question is whether these observations are compatible with supersymmetric models obeying $\\Omega h^2\\sim 0.11$ without violating existing collider constraints and precision measurements. In this talk, I review the fact the the Minimal Supersymmetric Model allows insufficient flexibility to achieve such compatibility, basically because of the highly constrained nature of the MSSM Higgs sector in relation to LEP limits on Higgs bosons. I then outline the manner in which the more flexible Higgs sectors of the Next-to-Minimal Supersymmetric Model and an Extended Next-to-Minimal Supersymmetric Model allow large $\\sigma_{SI}$ and $\\Omega h^2\\sim 0.11$ at low LSP mass without violating LEP, Tevatron, BaBar and other experimental limits. The relationship of the required Higgs sectors to the NMSSM ``ideal...
Trilinear couplings and scalar bound states in supersymmetric extensions of the standard model
Hernández, Pilar; Sanz, V
2001-01-01
The trilinear terms in minimal supersymmetric extensions of the standard model can be responsible of forming a bound state of scalars. In this talk we outline our results on the study of this bound state using a non-perturbative method, the exact renormalization group. We focus on the trilinear term between the Higgs and stop fields. (4 refs).
Neutral Higgs bosons in the standard model and in the minimal supersymmetric model: Searches at LEP
P Igo-Kemenes
2004-03-01
During the twelve years of operation of the $e^{+}e^{-}$ collider LEP, the associated collaborations, ALEPH, DELPHI, L3 and OPAL, have extensively searched for Higgs bosons over a broad range of masses. We present the final results from LEP for the standard model Higgs boson which are obtained from a statistical combination of the data from the four experiments. We also present preliminary combined results for neutral Higgs bosons in the minimal supersymmetric model (MSSM) where the Higgs sector is assumed to be CP invariant. Finally, we discuss an alternative MSSM scenario including CP violation in the Higgs sector.
Implications of improved Higgs mass calculations for supersymmetric models
Buchmueller, O. [Imperial College, London (United Kingdom). High Energy Physics Group; Dolan, M.J. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States). Theory Group; Ellis, J. [King' s College, London (United Kingdom). Theoretical Particle Physics and Cosmology Group; and others
2014-03-15
We discuss the allowed parameter spaces of supersymmetric scenarios in light of improved Higgs mass predictions provided by FeynHiggs 2.10.0. The Higgs mass predictions combine Feynman-diagrammatic results with a resummation of leading and subleading logarithmic corrections from the stop/top sector, which yield a significant improvement in the region of large stop masses. Scans in the pMSSM parameter space show that, for given values of the soft supersymmetry-breaking parameters, the new logarithmic contributions beyond the two-loop order implemented in FeynHiggs tend to give larger values of the light CP-even Higgs mass, M{sub h}, in the region of large stop masses than previous predictions that were based on a fixed-order Feynman-diagrammatic result, though the differences are generally consistent with the previous estimates of theoretical uncertainties. We re-analyze the parameter spaces of the CMSSM, NUHM1 and NUHM2, taking into account also the constraints from CMS and LHCb measurements of BR(B{sub s}→μ{sup +}μ{sup -}) and ATLAS searches for E{sub T} events using 20/fb of LHC data at 8 TeV. Within the CMSSM, the Higgs mass constraint disfavours tan β
On the unitarity of gauged non-compact world-sheet supersymmetric WZNW models
Bjornsson, Jonas
2008-01-01
In this paper we generalize our investigation of the unitarity of non-compact WZNW models connected to hermitian symmetric spaces to the N=1 world-sheet supersymmetric extension of these models. We will prove that these models are unitary in a BRST approach for antidominant highest weight representations if, and only if, the level and weights of the gauged subalgebra are integers. We will find new critical string theories in 7 and 9 space-time dimensions.
Bottom-Tau Yukawa Unification in the Next-to-Minimal Supersymmetric Standard Model
Allanach, Benjamin C
1994-01-01
We discuss the unification of the bottom quark and tau lepton Yukawa couplings within the framework of the next-to-minimal supersymmetric standard model. We compare the allowed regions of the $m_t$-$\\tan \\beta$ plane to those in the minimal supersymmetric standard model, and find that over much of the parameter space the deviation between the predictions of two models is small, and nearly always much less than the effect of current theoretical and experimental uncertainties in the bottom quark mass and the strong coupling constant. However over some regions of parameter space top-bottom Yukawa unification cannot be achieved. We also discuss the scaling of the light fermion masses and mixing angles, and show that to within current uncertainties the results of recent texture analyses performed for the minimal model also apply to the next-to-minimal model.
The Collider Phenomenology Of Supersymmetric Models (charged Higgs Boson, Tau Leptons)
Müller, D J
1998-01-01
The purpose of this study is to investigate the phenomenology of various supersymmetric models. First, the Minimal Supersymmetric Standard Model (MSSM) is investigated. This model contains an extended Higgs sector that includes a charged boson. The effect that this charged Higgs boson has on the signatures for top quark pair production at the Tevatron is investigated. The rest of the work is devoted to the phenomenology of models with gauge mediated supersymmetry breaking (GMSB). In GMSB models, the lighter stau can be the next to lightest supersymmetric particle. The signals at hadronic colliders for GMSB models with minimal visible sector content are explored for this case. A GMSB model with non-minimal visible sector content is also explored. This is the left-right symmetric GMSB model which contains doubly charged bosons and fermions that could be light enough in mass to be produced at Run II of the Tevatron. Findings and conclusions. The presence of a charged Higgs boson that is lighter than the top quar...
$\\mu\\to e\\gamma$ in a supersymmetric radiative neutrino mass model
Hundi, Raghavendra Srikanth
2016-01-01
We have considered a supersymmetric version of the inert Higgs doublet model, whose motivation is to explain smallness of neutrino masses and existence of dark matter. In this supersymmetric model, due to the presence of discrete symmetries, neutrinos acquire masses at loop level. After computing these neutrino masses, in order to fit the neutrino oscillation data, we have shown that by tuning some supersymmetry breaking soft parameters of the model, neutrino Yukawa couplings can be unsuppressed. In the above mentioned parameter space, we have computed branching ratio of the decay $\\mu\\to e\\gamma$. To be consistent with the current experimental upper bound on $Br(\\mu\\to e\\gamma)$, we have obtained constraints on the right-handed neutrino mass of this model.
Testing the minimal supersymmetric standard model with the mass of the boson
S Heinemeyer; W Hollik; D Stöckinger; A M Weber; G weiglein
2007-11-01
We review the currently most accurate evaluation of the boson mass, , in the minimal supersymmetric standard model (MSSM). It consists of a full one-loop calculation, including the complex phase dependence, all available MSSM two-loop corrections as well as the full standard model result. We analyse the impact of the phases in the scalar quark sector on and compare the prediction for based on all known higher-order contributions with the experimental results.
Higgs Boson Mass and Complex Snuetrino Dark Matter in the Supersymmetric Inverse Seesaw Models
Guo, Jun; Li, Tianjun; Liu, Yandong
2014-01-01
The discovery of a relatively heavy Standard Model (SM) -like Higgs boson challenges naturalness of the minimal supersymmetric standard model (MSSM) from both Higgs and dark matter (DM) sectors. We study these two aspects in the MSSM extended by the low-scale inverse seesaw mechanism. Firstly, it admits a sizable radiative correction on the Higgs boson mass m_h, up to \\sim 4 GeV in the case of an IR-fixed point of the coupling Y_\
Type III Seesaw and Dark Matter in a Supersymmetric Left-Right Model
Borah, Debasish
2009-01-01
We propose a new supersymmetric left right model with Higgs doublets carrying odd B-L charge, higgs bidoublet and heavy Higgs triplets with zero B-L charge and a set of sterile neutrinos which are singlet under the gauge group. We show that spontaneous parity violation can be achieved naturally in this model and the neutrino masses arise from the so called type III seesaw mechanism. We also discuss the possible phenomenology in the context of neutrino masses and dark matter.
A new Supersymmetric $SU(3)_L \\otimes U(1)_X$ gauge model
Díaz, R A; Rodríguez, José Alberto; Diaz, Rodolfo A.
2003-01-01
We present a new supersymmetric version of the $SU(3) \\otimes U(1)$ gauge model using a more economic content of particles. The model has a smaller set of free parameters than other possibilities considered before. The MSSM can be seen as an effective theory of this larger symmetry. We find that the upper bound of the ligthest CP-even Higgs boson can be moved up to 140 GeV.
LEP Higgs boson searches beyond the standard model and minimum supersymmetric standard model
Pauline Gagnon
2004-03-01
Ever since the center-of-mass energy was increased in 1995 above the $Z^{0}$ resonance, the four LEP experiments (ALEPH, DELPHI, OPAL and L3) have renewed their effort to search for the Higgs boson. Data taking ended in the year 2000 with about 130 pb-1 f data collected per experiment above 206 GeV in $e^{+} e^{-}$ collisions but the data analysis is still very active. Most recently, the wealth of theoretical models and predictions has stimulated new analyses and model interpretations which go beyond the standard model and minimal supersymmetric standard model. These include the searches for charged Higgs bosons, models with two Higgs field doublets, searches for ‘fermiophobic’ Higgs decay, invisible Higgs boson decays, decay-mode independent searches, and limits on Yukawa and anomalous Higgs couplings. I review the searches done by the four LEP experiments and present the LEP combined results when they exist.
Shedding light on new Wess-Zumino couplings with their corrections to all orders in alpha-prime
Hatefi, Ehsan
2013-01-01
Motivated by arXiv:1203.5553, we continue to match super string amplitudes with their own effective field theory. We carry out within full details the computations of the complete form of the amplitude of one closed string Ramond-Ramond field and three SYM vertex operators, namely one gauge field and two scalar fields in type IIB(A) super string theories. Making use of the recent two gauge and two scalar couplings to all orders of $\\alpha'$, we produce all the infinite gauge poles for $p=n$ case (with $n$ as RR field strength's rank and $p$ as the dimension of a D$_p$-brane). Proceeding with direct and full S-Matrix calculations, we are able to produce even all the infinite gauge poles in u-channel for $p-2=n$ case in field theory as well. New couplings for $p-2=n$ case with their all order $\\alpha'$ corrections are discovered. In addition, we explain how to find out all the infinite scalar poles of this amplitude in $s,t$-channels and produce them for $p+2=n$ case. By comparing all of the contact terms of th...
Schlichenmaier, Martin; Sheinman, Oleg K.
1998-01-01
Elements of a global operator approach to the WZWN theory for compact Riemann surfaces of arbitrary genus $g$ are given. Sheaves of representations of affine Krichever-Novikov algebras over a dense open subset of the moduli space of Riemann surfaces (respectively of smooth, projective complex curves) with $N$ marked points are introduced. It is shown that the tangent space of the moduli space at an arbitrary moduli point is isomorphic to a certain subspace of the Krichever-Novikov vector fiel...
Schlichenmaier, Martin; Sheinman, Oleg K.
2003-01-01
This paper continues the same-named article, Part I (math.QA/9812083). We give a global operator approach to the WZWN theory for compact Riemann surfaces of an arbitrary genus g with marked points. Globality means here that we use Krichever-Novikov algebras of gauge and conformal symmetries (i.e. algebras of global symmetries) instead of loop and Virasoro algebras (which are local in this context). The elements of this global approach are described in Part I. In the present paper we give the ...
Quasifixed point scenarios and the Higgs mass in the E6 inspired supersymmetric models
Nevzorov, R.
2014-03-01
We analyze the two-loop renormalization group (RG) flow of the gauge and Yukawa couplings within the E6 inspired supersymmetric models with extra U(1)N gauge symmetry under which right-handed neutrinos have zero charge. In these models, single discrete Z stretchy="false">˜2H symmetry forbids the tree-level flavor-changing transitions and the most dangerous baryon and lepton number violating operators. We consider two different scenarios A and B that involve extra matter beyond the minimal supersymmetric Standard Model contained in three and four 5+5¯ representations of SU(5), respectively, plus three SU(5) singlets which carry U(1)N charges. In scenario A, the measured values of the SU(2)W and U(1)Y gauge couplings lie near the fixed points of the RG equations. In scenario B, the contribution of two-loop corrections spoils the unification of gauge couplings, resulting in the appearance of the Landau pole below the grand unification scale MX. The solutions for the Yukawa couplings also approach the quasifixed points with increasing their values at the scale MX. We calculate the two-loop upper bounds on the lightest Higgs boson mass in the vicinity of these quasifixed points and compare the results of our analysis with the corresponding ones in the next-to-minimal supersymmetric Standard Model. In all these cases, the theoretical restrictions on the Standard-Model-like Higgs boson mass are rather close to 125 GeV.
Mitev, Vladimir
2010-08-15
The purpose of this thesis is to deepen our understanding of the fundamental properties and defining features of non-linear sigma models on superspaces. We begin by presenting the major concepts that we have used in our investigation, namely Lie superalgebras and supergroups, non-linear sigma models and two dimensional conformal field theory. We then exhibit a method, called cohomological reduction, that makes use of the target space supersymmetry of non-linear sigma models to compute certain correlation functions. We then show how the target space supersymmetry of Ricci flat Lie supergroups simplifies the perturbation theory of suitable deformed Wess-Zumino-Witten models, making it possible to compute boundary conformal weights to all orders. This is then applied to the OSP (2S+2 vertical stroke 2S) Gross-Neveu Model, leading to a dual description in terms of the sigma model on the supersphere S{sup 2S+1} {sup vertical} {sup stroke} {sup 2S}. With this results in mind, we then turn to the similar, yet more intricate, theory of the non-linear sigma model on the complex projective superspaces CP{sup N-1} {sup vertical} {sup stroke} {sup N}. The cohomological reduction allows us to compute several important quantities non-perturbatively with the help of the system of symplectic fermions. Combining this with partial perturbative results for the whole theory, together with numerical computations, we propose a conjecture for the exact evolution of boundary conformal weights for symmetry preserving boundary conditions. (orig.)
Kobayashi, K; Ashie, Y; Hosaka, J; Ishihara, K; Itow, Y; Kameda, J; Koshio, Y; Minamino, A; Mitsuda, C; Miura, M; Moriyama, S; Nakahata, M; Namba, T; Nambu, R; Obayashi, Y; Shiozawa, M; Suzuki, Y; Takeuchi, Y; Taki, K; Yamada, S; Ishitsuka, M; Kajita, T; Kaneyuki, K; Nakayama, S; Okada, A; Okumura, K; Ooyabu, T; Saji, C; Takenaga, Y; Desai, S; Kearns, E; Likhoded, S; Stone, J L; Sulak, L R; Wang, W; Goldhaber, M; Casper, D; Cravens, J P; Gajewski, W; Kropp, W R; Liu, D W; Mine, S; Smy, M B; Sobel, H W; Sterner, C W; Vagins, M R; Ganezer, K S; Hill, J E; Keig, W E; Jang, J S; Kim, J Y; Lim, I T; Scholberg, K; Walter, C W; Ellsworth, R W; Tasaka, S; Guillian, G; Kibayashi, A; Learned, J G; Matsuno, S; Takemori, D; Messier, M D; Hayato, Y; Ichikawa, A K; Ishida, T; Ishii, T; Iwashita, T; Kobayashi, T; Maruyama, T; Nakamura, K; Nitta, K; Oyama, Y; Sakuda, M; Totsuka, Y; Suzuki, A T; Hasegawa, M; Hayashi, K; Kato, I; Maesaka, H; Morita, T; Nakadaira, T; Nakaya, T; Nishikawa, K; Sasaki, T; Ueda, S; Yamamoto, S; Yokoyama, M; Haines, T J; Dazeley, S; Hatakeyama, S; Svoboda, R; Blaufuss, E; Goodman, J A; Sullivan, G W; Turcan, D; Habig, A; Fukuda, Y; Jung, C K; Kato, T; Malek, M; Mauger, C; McGrew, C; Sarrat, A; Sharkey, E; Yanagisawa, C; Toshito, T; Miyano, K; Tamura, N; Ishii, J; Kuno, Y; Yoshida, M; Kim, S B; Yoo, J; Okazawa, H; Ishizuka, T; Choi, Y; Seo, H K; Gando, Y; Hasegawa, T; Inoue, K; Shirai, J; Suzuki, A; Koshiba, M; Nakajima, Y; Nishijima, K; Harada, T; Ishino, H; Watanabe, Y; Kielczewska, D; Zalipska, J; Berns, H G; Gran, R; Shiraishi, K K; Stachyra, A; Washburn, K; Wilkes, R J
2005-01-01
We report the results for nucleon decay searches via modes favored by supersymmetric grand unified models in Super-Kamiokande. Using 1489 days of full Super-Kamiokande-I data, we searched for $p \\to \\bar{\
Transgression forms as source for topological gravity and Chern-Simons-Higgs theories
Valdivia, Omar
2014-01-01
Two main gauge invariant off-shell models are studied in this Thesis. I) Poincare-invariant topological gravity in even dimensions is formulated as a transgression field theory whose gauge connections are associated to linear and nonlinear realizations of the Poincare group ISO(d-1,1). The resulting theory is a gauged Wess-Zumino-Witten model whereby the transition functions relating gauge fields belong to the coset ISO(d-1,1)/SO(d-1,1). The supersymmetric extension leads to topological supergravity in two dimensions starting from a transgression field theory for the super-Poincare group in three dimensions. The construction is extended to a three-dimensional Chern-Simons theory of gravity invariant under the Maxwell algebra, where the corresponding Maxwell gauged Wess-Zumino-Witten model is obtained. II) dimensional reduction of Chern-Simons theories with arbitrary gauge group in a formalism based on equivariant principal bundles is considered. For the classical gauge groups the relations between equivariant...
Weiland, Cédric
2012-01-01
We study the impact of the inverse seesaw mechanism on several leptonic and hadronic low-energy flavour-violating observables in the context of the Minimal Supersymmetric Standard Model. Indeed, the contributions of the light right-handed sneutrinos from the inverse seesaw significantly enhance the Higgs-mediated penguin diagrams. We find that this can increase the different branching ratios by as much as two orders of magnitude.
Dark radiation and dark matter in supersymmetric axion models with high reheating temperature
Graf, Peter; Steffen, Frank Daniel
2013-01-01
Recent studies of the cosmic microwave background, large scale structure, and big bang nucleosynthesis (BBN) show trends towards extra radiation. Within the framework of supersymmetric hadronic axion models, we explore two high-reheating-temperature scenarios that can explain consistently extra radiation and cold dark matter (CDM), with the latter residing either in gravitinos or in axions. In the gravitino CDM case, axions from decays of thermal saxions provide extra radiation already prior ...
The HIGGS Boson Mass at 2 Loops in the Finely Tuned Split Supersymmetric Standard Model
Binger, M
2004-09-08
The mass of the Higgs boson in the finely tuned Split Supersymmetric Standard Model is calculated. All 1 loop threshold effects are included, in addition to the full RG running of the Higgs quartic coupling through 2 loops. The 2 loop corrections are very small, typically less than 1GeV. The 1 loop threshold corrections to the top yukawa coupling and the Higgs mass generally push the Higgs mass down a few GeV.
Impacts of supersymmetric higher derivative terms on inflation models in supergravity
Aoki, Shuntaro; Yamada, Yusuke [Department of Physics, Waseda University,Tokyo 169-8555 (Japan)
2015-07-14
We show the effects of supersymmetric higher derivative terms on inflation models in supergravity. The results show that such terms generically modify the effective kinetic coefficient of the inflaton during inflation if the cut off scale of the higher derivative operators is sufficiently small. In such a case, the η-problem in supergravity does not occur, and we find that the effective potential of the inflaton generically becomes a power type potential with a power smaller than two.
Testing the Higgs Sector of the Minimal Supersymmetric Standard Model at Large Hadron Colliders
Kunszt, Zoltán
1992-01-01
We study the Higgs sector of the Minimal Supersymmetric Standard Model, in the context of proton-proton collisions at LHC and SSC energies. We assume a relatively heavy supersymmetric particle spectrum, and include recent results on one-loop radiative corrections to Higgs-boson masses and couplings. We begin by discussing present and future constraints from the LEP experiments. We then compute branching ratios and total widths for the neutral ($h,H,A$) and charged ($H^\\pm$) Higgs particles. We present total cross-sections and event rates for the important discovery channels at the LHC and SSC. Promising physics signatures are given by $h \\to \\gamma \\gamma$, $H \\to \\gamma \\gamma$ or $Z^* Z^*$ or $\\tau^+ \\tau^-$, $A \\to \\tau^+ \\tau^-$, and $t \\to b H^+$ followed by $H^+ \\to \\tau^+ \
QCD corrections to the t$\\to$H+b decay within the minimal supersymmetric standard model
König, H
1994-01-01
I present the contribution of gluinos and scalar quarks to the decay rate of the top quark into a charged Higgs boson and a bottom quark within the minimal supersymmetric standard model, including the mixing of the scalar partners of the left- and right-handed top quark. I show that for certain values of the supersymmetric parameters the standard QCD loop corrections to this decay mode are diminished or enhanced by several 10 per cent. I show that not only a small value of 3 GeV for the gluino mass (small mass window) but also much larger values of several hundreds of GeV's have a non-neglible effect on this decay rate, against general belief. Last but not least, if the ratio of the vacuum expectation values of the Higgs bosons are taken in the limit of $v_1\\ll v_2$ I obtain a drastic enhancement due to a $\\tan\\beta$\\ dependence in the couplings.
SU(2|1) mechanics and harmonic superspace
Ivanov, E
2015-01-01
We define the worldline harmonic SU(2|1) superspace and its analytic subspace as a deformation of the flat N=4, d=1 harmonic superspace. The harmonic superfield description of the two mutually mirror off-shell (4,4,0) SU(2|1) supermultiplets is developed and the corresponding invariant actions are presented, as well as the relevant classical and quantum supercharges. Whereas the \\sigma-model actions exist for both types of the (4,4,0) multiplet, the invariant Wess-Zumino term can be defined only for one of them, thus demonstrating non-equivalence of these multiplets in the SU(2|1) case as opposed to the flat N=4, d=1 supersymmetry. A superconformal subclass of general SU(2|1) actions invariant under the trigonometric-type realizations of the supergroup D(2,1;\\alpha) is singled out. The superconformal Wess-Zumino actions possess an infinite-dimensional supersymmetry forming the centerless N=4 super Virasoro algebra. We solve a few simple instructive examples of the SU(2|1) supersymmetric quantum mechanics of t...
Fermionic Fields with Mass Dimension One as Supersymmetric Extension of the O'Raifeartaigh Model
Wunderle, Kai E.
The objective of this thesis is to derive a supersymmetric Lagrangian for fermionic fields with mass dimension one and to discuss their coupling to the O'Raifeartaigh model which is the simplest model permitting supersymmetry breaking. In addition it will be shown that eigenspinors of the charge conjugation operator (ELKO) exhibit a different transformation behaviour under discrete symmetries than previously assumed. The calculations confirm that ELKO spinors are not eigenspinors of the parity operator and satisfy (CPT)2 = -- I which identifies them as representation of a nonstandard Wigner class. However, it is found that ELKO spinors transform symmetrically under parity instead of the previously assumed asymmetry. Furthermore, it is demonstrated that ELKO spinors transform asymmetrically under time reversal which is opposite to the previously reported symmetric behaviour. These changes affect the (anti)commutation relations that are satisfied by the operators acting on ELKO spinors. Therefore, ELKO spinors satisfy the same (anti)commutation relations as Dirac spinors, even though they belong to two different representations of the Lorentz group. Afterwards, a supersymmetric model for fermionic fields with mass dimension one based on a general superfield with one spinor index is formulated. It includes the systematic derivation of all associated chiral and anti-chiral superfields up to third order in covariant derivatives. Starting from these fundamental superfields a supersymmetric on-shell Lagrangian that contains a kinetic term for the fermionic fields with mass dimension one is constructed. This on-shell Lagrangian is subsequently used to derive the on-shell super-current and to successfully formulate a consistent second quantisation for the component fields. In addition, the Hamiltonian in position space that corresponds to the supersymmetric Lagrangian is calculated. As the Lagrangian is by construction supersymmetric and the second quantisation of the
Locally supersymmetric D=3 non-linear sigma models
Wit, B. de; Tollsten, A. K.; Nicolai, H.
1992-01-01
We study non-linear sigma models with N local supersymmetries in three space-time dimensions. For N=1 and 2 the target space of these models is Riemannian or Kahler, respectively. All N>2 theories are associated with Einstein spaces. For N=3 the target space is quaternionic, while for N=4 it general
Renormalization of supersymmetric theories
Pierce, D.M.
1998-06-01
The author reviews the renormalization of the electroweak sector of the standard model. The derivation also applies to the minimal supersymmetric standard model. He discusses regularization, and the relation between the threshold corrections and the renormalization group equations. He considers the corrections to many precision observables, including M{sub W} and sin{sup 2}{theta}{sup eff}. He shows that global fits to the data exclude regions of supersymmetric model parameter space and lead to lower bounds on superpartner masses.
Liebler, Stefan Rainer
2011-09-15
The standard model of particle physics lacks on some shortcomings from experimental as well as from theoretical point of view: There is no approved mechanism for the generation of masses of the fundamental particles, in particular also not for the light, but massive neutrinos. In addition the standard model does not provide an explanation for the observance of dark matter in the universe. Moreover the gauge couplings of the three forces in the standard model do not unify, implying that a fundamental theory combining all forces can not be formulated. Within this thesis we address supersymmetric models as answers to these various questions, but instead of focusing on the most simple supersymmetrization of the standard model, we consider basic extensions, namely the next-to-minimal supersymmetric standard model (NMSSM), which contains an additional singlet field, and R-parity violating models. Using lepton number violating terms in the context of bilinear R-parity violation and the {mu}{nu}SSM we are able to explain neutrino physics intrinsically supersymmetric, since those terms induce a mixing between the neutralinos and the neutrinos. This thesis works out the phenomenology of the supersymmetric models under consideration and tries to point out differences to the well-known features of the simplest supersymmetric realization of the standard model. In case of the R-parity violating models the decays of the light neutralinos can result in displaced vertices. In combination with a light singlet state these displaced vertices might offer a rich phenomenology like non-standard Higgs decays into a pair of singlinos decaying with displaced vertices. Within this thesis we present some calculations at next order of perturbation theory, since one-loop corrections provide possibly large contributions to the tree-level masses and decay widths. We are using an on-shell renormalization scheme to calculate the masses of neutralinos and charginos including the neutrinos and
Anomaly mediated supersymmetric models and Higgs data from the LHC
Arbey, A; Mahmoudi, F; Tarhini, A
2013-01-01
Anomaly mediation models are well motivated supersymmetry breaking scenarios which appear as alternatives to the mSUGRA paradigm. These models are quite compelling from the theoretical point of view and it is therefore important to test if they are also viable models for phenomenology. We perform a study of these models in the light of all standard flavour, collider and dark matter constraints, including also the recent Higgs boson measurements for the mass and signal strengths in the different decay channels. The minimal AMSB scenario can satisfy in part of its parameter space the dark matter requirement but is only marginally consistent with the current Higgs boson mass value. The HyperCharge-AMSB and Mixed Moduli-AMSB scenarios can better describe present data from dark matter, flavour, low energy physics and are consistent with the measured mass of the Higgs boson. The inclusion of the preferred signal strengths for the Higgs boson decay channels shows that for tan(beta) > 5 the HC-AMSB and MM-AMSB models...
Supersymmetric quantum cosmology for Bianchi class A models
Macías, A; Socorro, J; Macías, Alfredo; Mielke, Eckehard W.; Socorro, José
1998-01-01
The canonical theory of (N=1) supergravity, with a matrix representation for the gravitino covector-spinor, is applied to the Bianchi class A spatially homogeneous cosmologies. The full Lorentz constraint and its implications for the wave function of the universe are analyzed in detail. We found that in this model no physical states other than the trivial "rest frame" type occur.
Mechanisms of supersymmetry breaking in the minimal supersymmetric standard model
Probir Roy
2003-02-01
We provide a bird’s eyeview of current ideas on supersymmetry breaking mechanisms in the MSSM. The essentials of gauge, gravity, anomaly and gaugino/higgsino mediation mechanisms are covered brieﬂy and the phenomenology of the associated models is touched upon. A few statement are also made on braneworld supersymmetry breaking.
Non-generic couplings in supersymmetric standard models
Evgeny I. Buchbinder
2015-09-01
Full Text Available We study two phases of a heterotic standard model, obtained from a Calabi–Yau compactification of the E8×E8 heterotic string, in the context of the associated four-dimensional effective theories. In the first phase we have a standard model gauge group, an MSSM spectrum, four additional U(1 symmetries and singlet fields. In the second phase, obtained from the first by continuing along the singlet directions, three of the additional U(1 symmetries are spontaneously broken and the remaining one is a B–L symmetry. In this second phase, dimension five operators inducing proton decay are consistent with all symmetries and as such, they are expected to be present. We show that, contrary to this expectation, these operators are forbidden due to the additional U(1 symmetries present in the first phase of the model. We emphasise that such “unexpected” absences of operators, due to symmetry enhancement at specific loci in the moduli space, can be phenomenologically relevant and, in the present case, protect the model from fast proton decay.
Single top production in a non-minimal supersymmetric model
Herquet, M.; Knegjens, R.; Laenen, E.L.M.P.
2010-01-01
We study single top production at the LHC in a SUSY-QCD model with a heavy Dirac gluino. The presence of a heavy Dirac gluino allows for notable top-up flavour changing neutral currents. In this scenario, we find that the process ug->tg gives the largest contribution to single top production via FCN
Single top production in a non-minimal supersymmetric model
Herquet, M.; Knegjens, R.; Laenen, E.
2010-01-01
We study single top production at the LHC in a SUSY-QCD model with a heavy Dirac gluino. The presence of a heavy Dirac gluino allows for notable top-up flavour changing neutral currents. In this scenario, we find that the process ug→tg gives the largest contribution to single top production via FCNC
Lectures on localization and matrix models in supersymmetric Chern-Simons-matter theories
Marino, Marcos
2011-01-01
In these lectures I give a pedagogical presentation of some of the recent progress in supersymmetric Chern-Simons-matter theories, coming from the use of localization and matrix model techniques. The goal is to provide a simple derivation of the exact interpolating function for the free energy of ABJM theory on the three-sphere, which implies in particular the N^{3/2} behavior at strong coupling. I explain in detail part of the background needed to understand this derivation, like holographic renormalization, localization of path integrals, and large N techniques in matrix models
Lectures on localization and matrix models in supersymmetric Chern-Simons-matter theories
Mariño, Marcos
2011-11-01
In these lectures, I give a pedagogical presentation of some of the recent progress in supersymmetric Chern-Simons-matter theories, coming from the use of localization and matrix model techniques. The goal is to provide a simple derivation of the exact interpolating function for the free energy of ABJM theory on the three-sphere, which implies in particular the N3/2 behavior at strong coupling. I explain in detail part of the background needed to understand this derivation, like holographic renormalization, localization of path integrals and large N techniques in matrix models.
Constraining the $SU(2)_R$ breaking scale in naturally R-parity conserving supersymmetric models
Huitu, K; Puolamäki, K
1997-01-01
We obtain an upper bound on the right-handed breaking scale in naturally R-parity conserving general left-right supersymmetric models. This translates into an upper bound on the right-handed gauge boson mass, $m_{W_R}\\lsim M_{SUSY}$, where $M_{SUSY}$ is the scale of SUSY breaking. This bound is independent of any assumptions for the couplings of the model, and follows from $SU(3)_c$ and $U(1)_{em}$ gauge invariance of the ground state of the theory.
Suppression of proton decay in the missing-partner model for supersymmetric SU(5) GUT
Hisano, J; Tobe, K; Yanagida, T
1994-01-01
We construct a missing-partner model for supersymmetric SU(5) GUT assuming the Peccei-Quinn symmetry, in which the SU(5) gauge coupling constant remains in the perturbative regime below the gravitational scale \\sim2.4\\times 10^{18}\\GEV. The Peccei-Quinn symmetry suppresses the dangerous dimension-five operators for the nucleon decay much below the limit from the present proton-decay experiments. We also stress that due to this suppression mechanism our model can accommodate even the large \\tan\\beta_H (\\sim 60) scenario which has been recently suggested to explain the observed value of the m_b/m_\\tau ratio.
New Aspects of Flavour Model Building in Supersymmetric Grand Unification
Spinrath, Martin
2010-01-01
We derive predictions for Yukawa coupling ratios within GUTs generated from operators with mass dimension four and five. These relations are a characteristic property of unified flavour models and can reduce the large number of free parameters related to the flavour sector of the SM. The Yukawa couplings of the down-type quarks and charged leptons are affected within SUSY models by tan beta-enhanced threshold corrections. We analyse these corrections and give simple analytic expressions and numerical estimates for them. The threshold corrections sensitively depend on the soft SUSY breaking parameters. Especially, they determine if the affected Yukawa couplings are enhanced or suppressed. In a first approach, we make some plausible assumptions about the soft SUSY parameters. In a second, more sophisticated approach we use three common breaking schemes in which all the soft breaking parameters at the electroweak scale can be calculated from only a handful of parameters. Within this approach, we apply various ph...
Constraint on the scale-unifying supersymmetric preon model from ? - ? mixing
Kim, Jongbae
1997-06-01
We study the flavour changing neutral current process in 0954-3899/23/6/005/img3 - 0954-3899/23/6/005/img4 mixing in the supersymmetric preon model (SPM). Compared to the minimal supersymmetric standard model (MSSM), one distinguishing feature of 0954-3899/23/6/005/img3 - 0954-3899/23/6/005/img4 mixing in the SPM is that there are new contributions from box diagrams involving two vector-like families of quarks and their supersymmetric (SUSY) partners with masses of order 1 TeV. Another special feature of the process in the SPM, in contrast to the MSSM, is that left - right squark 0954-3899/23/6/005/img7 - 0954-3899/23/6/005/img8 mixing is highly suppressed owing to symmetries of the underlying model. We calculate the SUSY box diagrams for 0954-3899/23/6/005/img3 - 0954-3899/23/6/005/img4 mixing for the case of the SPM, using observed 0954-3899/23/6/005/img3 - 0954-3899/23/6/005/img4 mass splitting, and obtain the constraint of 0954-3899/23/6/005/img13 on the squark mass degeneracy in the model. This upper limit is smaller by about a factor of 3.6 than the corresponding limit for the MSSM. The difference arises because of the absence of 0954-3899/23/6/005/img7 - 0954-3899/23/6/005/img8 mixing in the the preon model.
Muon g-2 vs LHC in Supersymmetric Models
Endo, Motoi; Iwamoto, Sho; Yoshinaga, Takahiro
2013-01-01
There is more than 3 sigma deviation between the experimental and theoretical results of the muon g-2. This suggests that some of the SUSY particles have a mass of order 100 GeV. We study searches for those particles at the LHC with particular attention to the muon g-2. In particular, the recent results on the searches for the non-colored SUSY particles are investigated in the parameter region where the muon g-2 is explained. The analysis is independent of details of the SUSY models. Future prospects of the collider searches are also discussed.
Muon g−2 vs LHC in supersymmetric models
Endo, Motoi; Hamaguchi, Koichi; Iwamoto, Sho; Yoshinaga, Takahiro [Department of Physics, The University of Tokyo,7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan)
2014-01-23
There is more than 3σ deviation between the experimental and theoretical results of the muon g−2. When interpreted in SUSY extensions of the SM, this anomaly suggests that some of the SUSY particles have a mass of order 100 GeV. We study searches for those particles at the LHC with particular attention to the muon g−2. In particular, the recent results on the searches for the non-colored SUSY particles are investigated in the parameter region where the muon g−2 is explained. The analysis is independent of details of the SUSY models. Future prospects of the collider searches are also discussed.
Supersymmetric invariant theories
Esipova, S R; Radchenko, O V
2013-01-01
We study field models for which a quantum action (i.e. the action appearing in the generating functional of Green functions) is invariant under supersymmetric transformations. We derive the Ward identity which is direct consequence of this invariance. We consider a change of variables in functional integral connected with supersymmetric transformations when its parameter is replaced by a nilpotent functional of fields. Exact form of the corresponding Jacobian is found. We find restrictions on generators of supersymmetric transformations when a consistent quantum description of given field theories exists.
Supersymmetric invariant theories
Esipova, S. R.; Lavrov, P. M.; Radchenko, O. V.
2014-04-01
We study field models for which a quantum action (i.e. the action appearing in the generating functional of Green functions) is invariant under supersymmetric transformations. We derive the Ward identity which is a direct consequence of this invariance. We consider a change of variables in functional integral connected with supersymmetric transformations when its parameter is replaced by a nilpotent functional of fields. Exact form of the corresponding Jacobian is found. We find restrictions on generators of supersymmetric transformations when a consistent quantum description of given field theories exists.
Radiative breaking of the minimal supersymmetric left–right model
Nobuchika Okada
2016-05-01
Full Text Available We study a variation to the SUSY Left–Right symmetric model based on the gauge group SU(3c×SU(2L×SU(2R×U(1BL. Beyond the quark and lepton superfields we only introduce a second Higgs bidoublet to produce realistic fermion mass matrices. This model does not include any SU(2R triplets. We calculate renormalization group evolutions of soft SUSY parameters at the one-loop level down to low energy. We find that an SU(2R slepton doublet acquires a negative mass squared at low energies, so that the breaking of SU(2R×U(1BL→U(1Y is realized by a non-zero vacuum expectation value of a right-handed sneutrino. Small neutrino masses are produced through neutrino mixings with gauginos. Mass limits on the SU(2R×U(1BL sector are obtained by direct search results at the LHC as well as lepton-gaugino mixing bounds from the LEP precision data.
Radiative Breaking of the Minimal Supersymmetric Left-Right Model
Okada, Nobuchika
2016-01-01
We propose a new variation to the SUSY Left-Right symmetric model based on the gauge group $SU(3)_c\\times SU(2)_L\\times SU(2)_R\\times U(1)_{BL}$. Beyond the quark and lepton superfields we only introduce a second Higgs bidoublet to produce realistic fermion mass matrices. This model does not include any $SU(2)_R$ triplets. We calculate renormalization group evolutions of soft SUSY parameters at the one-loop level down to low energy. We find that an $SU(2)_R$ slepton doublet acquires a negative mass squared at low energies, so that the breaking of $SU(2)_R\\times U(1)_{BL}\\rightarrow U(1)_Y$ is realized by a non-zero vacuum expectation value of a right-handed sneutrino. Small neutrino masses are produced through neutrino mixings with gauginos. Mass limits on the $SU(2)_R\\times U(1)_{BL}$ sector are obtained by direct search results at the LHC as well as lepton-gaugino mixing bounds from the LEP precision data.
Phenomenological study of the minimal R-symmetric supersymmetric standard model
Diessner, Philip
2016-10-20
The Standard Model (SM) of particle physics gives a comprehensive description of numerous phenomena concerning the fundamental components of nature. Still, open questions and a clouded understanding of the underlying structure remain. Supersymmetry is a well motivated extension that may account for the observed density of dark matter in the universe and solve the hierarchy problem of the SM. The minimal supersymmetric extension of the SM (MSSM) provides solutions to these challenges. Furthermore, it predicts new particles in reach of current experiments. However, the model has its own theoretical challenges and is under fire from measurements provided by the Large Hadron Collider (LHC). Nevertheless, the concept of supersymmetry has an elegance which not only shines in the MSSM. Hence, it is also of interest to examine non-minimal supersymmetric models. They have benefits similar to the MSSM and may solve its shortcomings. R-symmetry is the only global symmetry allowed that does not commutate with supersymmetry and Lorentz symmetry. Thus, extending a supersymmetric model with R-symmetry is a theoretically well motivated endeavor to achieve the complete symmetry content of a field theory. Such a model provides a natural explanation for non-discovery in the early runs of the LHC and leads to further predictions distinct from those of the MSSM. The work described in this thesis contributes to the effort by studying the minimal R-symmetric supersymmetric extension of the SM (MRSSM). Important aspects of its physics and the dependence of observables on the parameter space of the MRSSM are investigated. The discovery of a scalar particle compatible with the Higgs boson of the SM at the LHC was announced in 2012. It is the first and crucial task of this thesis to understand the underlying mechanisms leading to the correct Higgs boson mass prediction in the MRSSM. Then, the relevant regions of parameter space are investigated and it is shown that they are also in agreement
N=4 Supersymmetric Yang-Mills on S^3 in Plane Wave Matrix Model at Finite Temperature
Kitazawa, Yoshihisa
2008-01-01
We investigate the large N reduced model of gauge theory on a curved spacetime through the plane wave matrix model. We formally derive the action of the N=4 supersymmetric Yang-Mills theory on R \\times S^3 from the plane wave matrix model in the large N limit. Furthermore, we evaluate the effective action of the plane wave matrix model up to the two-loop level at finite temperature. We find that the effective action is consistent with the free energy of the N=4 supersymmetric Yang-Mills theory on S^3 at high temperature limit where the planar contributions dominate. We conclude that the plane wave matrix model can be used as a large N reduced model to investigate nonperturbative aspects of the N=4 supersymmetric Yang-Mills theory on R \\times S^3.
A More Flavored Higgs boson in Supersymmetric models
Díaz-Cruz, J L
2003-01-01
A More flavored Higgs boson arises when the flavor structure encoded in SUSY extensions of the SM is transmited to the Higgs sector. The flavor-Higgs transmition mechanism can have a radiative or mixing origin, as it is illustrated with several examples, and can produce interesting Higgs signatures that can be probed at future high-energy colliders. Within the MSSM, the flavor mediation mechanism can be of radiative type, as it is realized though gaugino-slepton loops, which transmit the flavorstructture of the soft-breaking sector to the Higgs bosons. In particular we focus on evaluating the contributions from the general trilinear terms to the lepton flavor violating Higgs (LFV) vertices. On the other hand, as an example of flavor mediation through mixing, we discuss an E_6 inspired multi-Higgs model, with an abelian flavor symmetry, where LFV as well as lepton flavor conserving Higgs effects are found to arise, though in this case at tree-level. We find that Tevatron and LHC can provide information on the ...
Higgs mass and right-handed sneutrino WIMP in a supersymmetric 3 -3 -1 model
Pires, C. A. de S.; da Silva, P. S. Rodrigues; Santos, A. C. O.; Siqueira, Clarissa
2016-09-01
This work deals with the right-handed sneutrino as thermal cold dark matter candidate. This scalar emerges in a supersymmetric version of the S U (3 )c⊗S U (3 )L⊗U (1 )X gauge model where right-handed neutrinos are a natural component of leptonic chiral scalar supermultiplets. We first consider the issue of a 125 GeV Higgs boson mass in this model, showing that constraints on the stop mass and trilinear soft coupling are considerably alleviated compared to the minimal supersymmetric standard model. Then, we investigate the region of parameter space that is consistent with right-handed sneutrino as thermal cold dark matter, under the light of Planck results on the relic abundance and direct detection from the LUX experiment. This sneutrino mainly annihilates through an extra neutral gauge boson, Z', and Higgs exchange so that the physics of dark matter is somewhat related to the parameters determining Higgs and Z' masses. We then obtain that the right-handed sneutrino in this model must be heavier than 400 GeV to conform with Planck and LUX, simultaneously constraining the Z' mass to be above 2400 GeV, which is in perfect agreement with LHC searches in a nonsupersymmetric version of this model.
Gravitational waves from domain walls in the next-to-minimal supersymmetric standard model
Kadota, Kenji [Center for Theoretical Physics of the Universe, Institute for Basic Science,Daejeon 305-811 (Korea, Republic of); Kawasaki, Masahiro [Institute for Cosmic Ray Research, The University of Tokyo,5-1-5 Kashiwa-no-ha, Kashiwa City, Chiba 277-8582 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI),Todai Institutes for Advanced Study, The University of Tokyo,5-1-5 Kashiwa-no-ha, Kashiwa City, Chiba 277-8582 (Japan); Saikawa, Ken’ichi [Department of Physics, Tokyo Institute of Technology,2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551 (Japan)
2015-10-16
The next-to-minimal supersymmetric standard model predicts the formation of domain walls due to the spontaneous breaking of the discrete Z{sub 3}-symmetry at the electroweak phase transition, and they collapse before the epoch of big bang nucleosynthesis if there exists a small bias term in the potential which explicitly breaks the discrete symmetry. Signatures of gravitational waves produced from these unstable domain walls are estimated and their parameter dependence is investigated. It is shown that the amplitude of gravitational waves becomes generically large in the decoupling limit, and that their frequency is low enough to be probed in future pulsar timing observations.
QCD Corrections to K-Kbar Mixing in R-symmetric Supersymmetric Models
Blechman, Andrew E
2008-01-01
The leading-log QCD corrections to K-Kbar mixing in R-symmetric supersymmetric models are computed using effective field theory techniques. The spectrum topology where the gluino is significantly heavier than the squarks is motivated and focused on. It is found that, like in the MSSM, QCD corrections can tighten the kaon mass difference bound by roughly a factor of three. CP violation is also briefly considered, where QCD corrections can constrain phases to be as much as a factor of ten smaller than the uncorrected value.
QCD Corrections to K-Kbar Mixing in R-symmetric Supersymmetric Models
Blechman, Andrew E.; Ng, Siew-Phang
2008-01-01
The leading-log QCD corrections to K-Kbar mixing in R-symmetric supersymmetric models are computed using effective field theory techniques. The spectrum topology where the gluino is significantly heavier than the squarks is motivated and focused on. It is found that, like in the MSSM, QCD corrections can tighten the kaon mass difference bound by roughly a factor of three. CP violation is also briefly considered, where QCD corrections can constrain phases to be as much as a factor of ten small...
Precise predictions for Higgs-masses in the next-to-minimal supersymmetric standard model (NMSSM)
Drechsel, Peter; Weiglein, Georg [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Heinemeyer, Sven; Galeta, Leo [Instituto de Fisica de Cantabria, Edificio Juan Jorda, Santander (Spain)
2015-07-01
The NMSSM represents an elegant and well motivated alternative description for the observed phenomenology in high energy physics. In this theory a scalar singlet together with its superpartner is added to the Higgs-sector of the Minimal Supersymmetric Standard Model (MSSM). In order to allow significant testing of the NMSSM by experiments precise predictions for the parameters of the theory are a necessity. The talk focuses on the prediction for the Higgs-masses in the NMSSM up to 2-loop order obtained by diagrammatic methods. The numerical impact of partial contributions is discussed as well as the validity and scope of the presented results.
Light Stop, Heavy Higgs, and Heavy Gluino in Supersymmetric Standard Models with Extra Matters
Hisano, Junji; Kuwahara, Takumi
2016-01-01
We have explored the possibilities of scenarios with heavy gluinos and light stops in the supersymmetric (SUSY) standard models with extra vector-like multiplets. If we assume the hierarchical structure for soft masses of MSSM scalar fields and extra scalars, the light stop and the observed Higgs boson can be realized. While the stau is the lightest SUSY particle (LSP) in broad parameter space, we have found the neutralino LSP is realized in the case that the non-zero soft parameters for the MSSM Higgs doublets or the non-universal gaugino masses are assumed.
Supergravity in Two Spacetime Dimensions
Ertl, M F
2001-01-01
The constraints of the superfield method in two-dimensional supergravity are adapted to allow for nonvanishing bosonic torsion. As the analysis of the Bianchi identities reveals, a new vector superfield is encountered besides the well-known scalar one. The constraints are solved both with superfields using a special decomposition of the supervielbein, and explicitly in terms of component fields in a Wess-Zumino gauge. The graded Poisson Sigma Model (gPSM) is the alternative method used to construct supersymmetric gravity theories. In this context the graded Jacobi identity is solved algebraically for general cases. Some of the Poisson algebras obtained are singular, or several potentials contained in them are restricted. This is discussed for a selection of representative algebras. It is found, that the gPSM is far more flexible and it shows the inherent ambiguity of the supersymmetric extension more clearly than the superfield method. Among the various models spherically reduced Einstein gravity and gravity ...
Implications of a 125 GeV Higgs for supersymmetric models
Arbey, A. [Universite de Lyon, Universite Lyon 1, CNRS/IN2P3, UMR5822 IPNL, F-69622 Villeurbanne Cedex (France); CERN, CH-1211 Geneva 23 (Switzerland); Observatoire de Lyon, CNRS, UMR5574 CRAL, Ecole Normale Superieure de Lyon, F-69561 Saint-Genis Laval Cedex (France); Battaglia, M. [CERN, CH-1211 Geneva 23 (Switzerland); Santa Cruz Institute of Particle Physics, University of California, Santa Cruz, CA 95064 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Djouadi, A., E-mail: abdelhak.djouadi@th.u-psud.fr [CERN, CH-1211 Geneva 23 (Switzerland); Laboratoire de Physique Theorique, Universite Paris XI and CNRS, F-91405 Orsay (France); Mahmoudi, F. [CERN, CH-1211 Geneva 23 (Switzerland); Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, BP 10448, 63000 Clermont-Ferrand (France); Quevillon, J. [Laboratoire de Physique Theorique, Universite Paris XI and CNRS, F-91405 Orsay (France)
2012-02-14
Preliminary results of the search for a Standard Model like Higgs boson at the LHC with 5 fb{sup -1} data have just been presented by the ATLAS and CMS Collaborations and an excess of events at a mass of Almost-Equal-To 125 GeV has been reported. If this excess of events is confirmed by further searches with more data, it will have extremely important consequences in the context of supersymmetric extensions of the Standard Model and, in particular the minimal one, the MSSM. We show that for a standard-like Higgs boson with a mass 123
Radiative Symmetry Breaking in the Supersymmetric Minimal B-L Extended Standard Model
Burell, Zachary
2016-01-01
The Standard Model (SM) of particle physics is a precise model of electroweak interactions, however there is growing tension between the SM and observations (neutrino oscillations, dark matter, dark energy, baryogenesis, among others). There is no reason to expect the validity of the ad hoc SM to remain intact at energy scales above a few TeV, thus a more fundamental theory will almost certainly be required. Motivated by these considerations, we investigate a Supersymmetric version of a natural extension of the SM, the $U(1)_{B-L}$ model, that is obtained by gauging the accidental B-L symmetry that exists in the ordinary SM. The Supersymmetric $U(1)_{B-L}$ extended SM can resolve the neutrino mass problem, the dark matter problem, the hierarchy problem, and provides a mechanism for establishing the observed baryon asymmetry of the Universe. When we include quantum corrections to the Higgs potential of the model, we find that Radiative $B-L$ symmetry breaking occurs through the interplay between large Majorana...
Quantum groups as generalized gauge symmetries in WZNW models. Part II. The quantized model
Hadjiivanov, L.; Furlan, P.
2017-07-01
This is the second part of a paper dealing with the "internal" (gauge) symmetry of the Wess-Zumino-Novikov-Witten (WZNW) model on a compact Lie group G. It contains a systematic exposition, for G = SU( n), of the canonical quantization based on the study of the classical model (performed in the first part) following the quantum group symmetric approach first advocated by L.D. Faddeev and collaborators. The internal symmetry of the quantized model is carried by the chiral WZNW zero modes satisfying quadratic exchange relations and an n-linear determinant condition. For generic values of the deformation parameter the Fock representation of the zero modes' algebra gives rise to a model space of U q ( sl( n)). The relevant root of unity case is studied in detail for n = 2 when a "restricted" (finite dimensional) quotient quantum group is shown to appear in a natural way. The module structure of the zero modes' Fock space provides a specific duality with the solutions of the Knizhnik-Zamolodchikov equation for the four point functions of primary fields suggesting the existence of an extended state space of logarithmic CFT type. Combining left and right zero modes (i.e., returning to the 2 D model), the rational CFT structure shows up in a setting reminiscent to covariant quantization of gauge theories in which the restricted quantum group plays the role of a generalized gauge symmetry.
Supersymmetric Fits after the Higgs Discovery and Implications for Model Building
Ellis, John
2014-01-01
The data from the first run of the LHC at 7 and 8 TeV, together with the information provided by other experiments such as precision electroweak measurements, flavour measurements, the cosmological density of cold dark matter and the direct search for the scattering of dark matter particles in the LUX experiment, provide important constraints on supersymmetric models. Important information is provided by the ATLAS and CMS measurements of the mass of the Higgs boson, as well as the negative results of searches at the LHC for events with missing transverse energy accompanied by jets, and the LHCb and CMS measurements off BR($B_s \\to \\mu^+ \\mu^-$). Results are presented from frequentist analyses of the parameter spaces of the CMSSM and NUHM1. The global $\\chi^2$ functions for the supersymmetric models vary slowly over most of the parameter spaces allowed by the Higgs mass and the missing transverse energy search, with best-fit values that are comparable to the $\\chi^2$ for the Standard Model. The $95\\%$ CL lower...
Bounds on the Higgs mass in the standard model and the minimal supersymmetric standard model
Quiros, M.
1995-01-01
Depending on the Higgs-boson and top-quark masses, M_H and M_t, the effective potential of the {\\bf Standard Model} can develop a non-standard minimum for values of the field much larger than the weak scale. In those cases the standard minimum becomes metastable and the possibility of decay to the non-standard one arises. Comparison of the decay rate to the non-standard minimum at finite (and zero) temperature with the corresponding expansion rate of the Universe allows to identify the region, in the (M_H, M_t) plane, where the Higgs field is sitting at the standard electroweak minimum. In the {\\bf Minimal Supersymmetric Standard Model}, approximate analytical expressions for the Higgs mass spectrum and couplings are worked out, providing an excellent approximation to the numerical results which include all next-to-leading-log corrections. An appropriate treatment of squark decoupling allows to consider large values of the stop and/or sbottom mixing parameters and thus fix a reliable upper bound on the mass o...
The neutralino sector in the U(1)-extended supersymmetric standard model
Choi, S.Y. [Chonbuk National Univ., Jeonju (Korea). Dept. of Physics and RIPC]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Haber, H.E. [California Univ., Santa Cruz, CA (United States). SCIPP; Kalinowski, J. [Warsaw Univ. (Poland). Inst. of Theoretical Physics; Zerwas, P.M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[California Univ., Santa Cruz, CA (United States). SCIPP
2006-12-15
Motivated by grand unified theories and string theories we analyze the general structure of the neutralino sector in the USSM, an extension of the Minimal Supersymmetric Standard Model that involves a broken extra U(1) gauge symmetry. This supersymmetric U(1)-extended model includes an Abelian gauge superfield and a Higgs singlet superfield in addition to the standard gauge and Higgs superfields of the MSSM. The interactions between the MSSM fields and the new fields are in general weak and the mixing is small, so that the coupling of the two subsystems can be treated perturbatively. As a result, the mass spectrum and mixing matrix in the neutralino sector can be analyzed analytically and the structure of this 6-state system is under good theoretical control. We describe the decay modes of the new states and the impact of this extension on decays of the original MSSM neutralinos, including radiative transitions in cross-over zones. Production channels in cascade decays at the LHC and pair production at e{sup +}e{sup -} colliders are also discussed. (orig.)
The Neutralino Sector in the U(1)-Extended Supersymmetric Standard Model
Choi, S Y; Kalinowski, Jan; Zerwas, P M
2006-01-01
Motivated by grand unified theories and string theories we analyze the general structure of the neutralino sector in the USSM, an extension of the Minimal Supersymmetric Standard Model that involves a broken extra U(1) gauge symmetry. This supersymmetric U(1)-extended model includes an Abelian gauge superfield and a Higgs singlet superfield in addition to the standard gauge and Higgs superfields of the MSSM. The interactions between the MSSM fields and the new fields are in general weak and the mixing is small, so that the coupling of the two subsystems can be treated perturbatively. As a result, the mass spectrum and mixing matrix in the neutralino sector can be analyzed analytically and the structure of this 6-state system is under good theoretical control. We describe the decay modes of the new states and the impact of this extension on decays of the original MSSM neutralinos, including radiative transitions in cross-over zones. Production channels in cascade decays at the LHC and pair production at $e^+e^...
The neutralino sector in the U(1)-extended supersymmetric Standard Model
Choi, S. Y.; Haber, H. E.; Kalinowski, J.; Zerwas, P. M.
2007-08-01
Motivated by grand unified theories and string theories we analyze the general structure of the neutralino sector in the USSM, an extension of the minimal supersymmetric Standard Model that involves a broken extra U(1) gauge symmetry. This supersymmetric U(1)-extended model includes an Abelian gauge superfield and a Higgs singlet superfield in addition to the standard gauge and Higgs superfields of the MSSM. The interactions between the MSSM fields and the new fields are in general weak and the mixing is small, so that the coupling of the two subsystems can be treated perturbatively. As a result, the mass spectrum and mixing matrix in the neutralino sector can be analyzed analytically and the structure of this 6-state system is under good theoretical control. We describe the decay modes of the new states and the impact of this extension on decays of the original MSSM neutralinos, including radiative transitions in cross-over zones. Production channels in cascade decays at the LHC and pair production at ee colliders are also discussed.
Deformed Matrix Models, Supersymmetric Lattice Twists and N=1/4 Supersymmetry
Unsal, Mithat
2008-09-24
A manifestly supersymmetric nonperturbative matrix regularization for a twisted version of N = (8, 8) theory on a curved background (a two-sphere) is constructed. Both continuum and the matrix regularization respect four exact scalar supersymmetries under a twisted version of the supersymmetry algebra. We then discuss a succinct Q = 1 deformed matrix model regularization of N = 4 SYM in d = 4, which is equivalent to a non-commutative A*{sub 4} orbifold lattice formulation. Motivated by recent progress in supersymmetric lattices, we also propose a N = 1/4 supersymmetry preserving deformation of N = 4 SYM theory on R{sup 4}. In this class of N = 1/4 theories, both the regularized and continuum theory respect the same set of (scalar) supersymmetry. By using the equivalence of the deformed matrix models with the lattice formulations, we give a very simple physical argument on why the exact lattice supersymmetry must be a subset of scalar subalgebra. This argument disagrees with the recent claims of the link approach, for which we give a new interpretation.
Extended supersymmetric sigma models in AdS_4 from projective superspace
Butter, Daniel; Lindstrom, Ulf; Tartaglino-Mazzucchelli, Gabriele
2012-01-01
There exist two superspace approaches to describe N=2 supersymmetric nonlinear sigma models in four-dimensional anti-de Sitter (AdS_4) space: (i) in terms of N=1 AdS chiral superfields, as developed in arXiv:1105.3111 and arXiv:1108.5290; and (ii) in terms of N=2 polar supermultiplets using the AdS projective-superspace techniques developed in arXiv:0807.3368. The virtue of the approach (i) is that it makes manifest the geometric properties of the N=2 supersymmetric sigma-models in AdS_4. The target space must be a non-compact hyperkahler manifold endowed with a Killing vector field which generates an SO(2) group of rotations on the two-sphere of complex structures. The power of the approach (ii) is that it allows us, in principle, to generate hyperkahler metrics as well as to address the problem of deformations of such metrics. Here we show how to relate the formulation (ii) to (i) by integrating out an infinite number of N=1 AdS auxiliary superfields and performing a superfield duality transformation. We al...
Searching for Composite Higgs Models at the LHC
Flacke, Thomas
Composite Higgs models have the potential to provide a solution to the hierarchy problem and a dynamical explanation for the generation of the Higgs potential. They can be tested at the LHC as the new sector which underlies electroweak symmetry breaking must become strong in the TeV regime, which implies additional bound states beyond the Higgs. In this paper, we first discuss prospects and search strategies for top partners (and other quark partners) in the strongly coupled sector, which we study in an effective field theory setup. In the second part of the proceedings, we go beyond the effective field theory approach. We discuss potential UV embeddings for composite Higgs models which contain a Higgs as well as top partners. We show that in all of these models, additional pseudo-Nambu-Goldstone bosons beyond the Higgs are present. In particular, all of the models contain a pseudoscalar which couples to the Standard Model gauge fields through Wess-Zumino-Witten terms, providing a prime candidate for a di-boson (including a di-photon) resonance. The models also contain colored pNGBs which can be searched for at the LHC.
Searching for composite Higgs models at the LHC
Flacke, Thomas
2016-07-01
Composite Higgs models have the potential to provide a solution to the hierarchy problem and a dynamical explanation for the generation of the Higgs potential. They can be tested at the LHC as the new sector which underlies electroweak symmetry breaking must become strong in the TeV regime, which implies additional bound states beyond the Higgs. In this paper, we first discuss prospects and search strategies for top partners (and other quark partners) in the strongly coupled sector, which we study in an effective field theory setup. In the second part of the proceedings, we go beyond the effective field theory approach. We discuss potential UV embeddings for composite Higgs models which contain a Higgs as well as top partners. We show that in all of these models, additional pseudo-Nambu-Goldstone bosons beyond the Higgs are present. In particular, all of the models contain a pseudoscalar which couples to the Standard Model gauge fields through Wess-Zumino-Witten terms, providing a prime candidate for a di-boson (including a di-photon) resonance. The models also contain colored pNGBs which can be searched for at the LHC.
The WZNW model on PSU(1, 1 vertical stroke 2)
Goetz, G. [CEA Centre d' Etudes de Saclay, 91 - Gif-sur-Yvette (France). Service de Physique Theorique; Quella, T. [King' s College London (United Kingdom). Dept. of Mathematics]|[Amsterdam Univ. (Netherlands). KdV Institute for Mathematics; Schomerus, V. [CEA Centre d' Etudes de Saclay, 91 - Gif-sur-Yvette (France). Service de Physique Theorique]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2006-10-15
According to the work of Berkovits, Vafa and Witten, the non-linear sigma model on the supergroup PSU(1,1 vertical stroke 2) is the essential building block for string theory on AdS{sub 3}xS{sup 3}xT{sup 4}. Models associated with a non-vanishing value of the RR flux can be obtained through a psu(1,1 vertical stroke 2) invariant marginal deformation of the WZNW model on PSU(1,1 vertical stroke 2). We take this as a motivation to present a manifestly psu(1,1 vertical stroke 2) covariant construction of the model at the Wess-Zumino point, corresponding to a purely NSNS background 3-form flux. At this point the model possesses an enhanced psu(1,1 vertical stroke 2) current algebra symmetry whose representation theory, including explicit character formulas, is developed systematically in the first part of the paper. The space of vertex operators and a free fermion representation for their correlation functions is our main subject in the second part. Contrary to a widespread claim, bosonic and fermionic fields are necessarily coupled to each other. The interaction changes the supersymmetry transformations, with drastic consequences for the multiplets of localized normalizable states in the model. It is only this fact which allows us to decompose the full state space into multiplets of the global supersymmetry. We analyze these decompositions systematically as a preparation for a forthcoming study of the RR deformation. (orig.)
Shell-model study on event rates of lightest supersymmetric particles scattering off 83Kr and 125Te
Pirinen, P.; Srivastava, P. C.; Suhonen, J.; Kortelainen, M.
2016-05-01
We investigate the elastic and inelastic scattering of lightest supersymmetric particle (LSP) dark matter off two possible target nuclei, 83Kr and 125Te. For the nuclear-structure calculations, we employ the nuclear shell model using recently generated realistic interactions. We have condensed the nuclear-physics contribution to a set of nuclear-structure factors that are independent of the adopted supersymmetric (SUSY) model. Total event rates are then easily calculated by combining the nuclear-structure factors with SUSY parameters of choice. In particular, 125Te shows promise as a detector material with both the elastic and inelastic channels yielding an appreciable nuclear response.
Supersymmetric models on magnetized orbifolds with flux-induced Fayet-Iliopoulos terms
Abe, Hiroyuki; Sumita, Keigo; Tatsuta, Yoshiyuki
2016-01-01
We study supersymmetric (SUSY) models derived from the ten-dimensional SUSY Yang- Mills theory compactified on magnetized orbifolds, with nonvanishing Fayet-Iliopoulos (FI) terms induced by magnetic fluxes in extra dimensions. Allowing the presence of FI-terms relaxes a constraint on flux configurations in SUSY model building based on magnetized backgrounds. In this case, charged fields develop their vacuum expectation values (VEVs) to cancel the FI-terms in the D-flat directions of fluxed gauge symmetries, which break the gauge symmetries and lead to a SUSY vacuum. Based on this idea, we propose a new class of SUSY magnetized orbifold models with three generations of quarks and leptons. Especially, we construct a model where the right-handed sneutrinos develop their VEVs which restore the supersymmetry but yield lepton number violating terms below the compactification scale, and show their phenomenological consequences.
Supersymmetric models on magnetized orbifolds with flux-induced Fayet-Iliopoulos terms
Abe, Hiroyuki; Kobayashi, Tatsuo; Sumita, Keigo; Tatsuta, Yoshiyuki
2017-01-01
We study supersymmetric (SUSY) models derived from the ten-dimensional SUSY Yang-Mills theory compactified on magnetized orbifolds, with nonvanishing Fayet-Iliopoulos (FI) terms induced by magnetic fluxes in extra dimensions. Allowing the presence of FI-terms relaxes a constraint on flux configurations in SUSY model building based on magnetized backgrounds. In this case, charged fields develop their vacuum expectation values to cancel the FI-terms in the D-flat directions of fluxed gauge symmetries, which break the gauge symmetries and lead to a SUSY vacuum. Based on this idea, we propose a new class of SUSY magnetized orbifold models with three generations of quarks and leptons. Especially, we construct a model where the right-handed sneutrinos develop their vacuum expectation values which restore the supersymmetry but yield lepton number violating terms below the compactification scale, and show their phenomenological consequences.
Götz, G; Schomerus, V; Gotz, Gerhard; Quella, Thomas; Schomerus, Volker
2007-01-01
According to the work of Berkovits, Vafa and Witten (hep-th/9902098), the non-linear sigma model on the supergroup PSU(1,1|2) is the essential building block for string theory on AdS(3)xS(3)xT(4). Models associated with a non-vanishing value of the RR flux can be obtained through a psu(1,1|2) invariant marginal deformation of the WZNW model on PSU(1,1|2). We take this as a motivation to present a manifestly psu(1,1|2) covariant construction of the model at the Wess-Zumino point, corresponding to a purely NSNS background 3-form flux. At this point the model possesses an enhanced psu(1,1|2) current algebra symmetry whose representation theory, including explicit character formulas, is developed systematically in the first part of the paper. The space of vertex operators and a free fermion representation for their correlation functions is our main subject in the second part. Contrary to a widespread claim, bosonic and fermionic fields are necessarily coupled to each other. The interaction changes the supersymmet...
Yamaguchi, Masahiro
2016-01-01
Discarding the prejudice about fine tuning, we propose a novel and efficient approach to identify relevant regions of fundamental parameter space in supersymmetric models with some amount of fine tuning. The essential idea is the mapping of experimental constraints at a low energy scale, rather than the parameter sets, to those of the fundamental parameter space. Applying this method to the non-universal Higgs masses model, we identify a new interesting superparticle mass pattern where some of the first two generation squarks are light whilst the stops are kept heavy as 6TeV. Furthermore, as another application of this method, we show that the discrepancy of the muon anomalous magnetic dipole moment can be filled by a supersymmetric contribution within the 1 {\\sigma} level of the experimental and theoretical errors, which was overlooked by the previous studies due to the required terrible fine tuning.
Dark radiation and dark matter in supersymmetric axion models with high reheating temperature
Graf, Peter; Steffen, Frank Daniel, E-mail: graf@mpp.mpg.de, E-mail: steffen@mpp.mpg.de [Max-Planck-Institut für Physik, Föhringer Ring 6, D–80805 Munich (Germany)
2013-12-01
Recent studies of the cosmic microwave background, large scale structure, and big bang nucleosynthesis (BBN) show trends towards extra radiation. Within the framework of supersymmetric hadronic axion models, we explore two high-reheating-temperature scenarios that can explain consistently extra radiation and cold dark matter (CDM), with the latter residing either in gravitinos or in axions. In the gravitino CDM case, axions from decays of thermal saxions provide extra radiation already prior to BBN and decays of axinos with a cosmologically required TeV-scale mass can produce extra entropy. In the axion CDM case, cosmological constraints are respected with light eV-scale axinos and weak-scale gravitinos that decay into axions and axinos. These decays lead to late extra radiation which can coexist with the early contributions from saxion decays. Recent results of the Planck satellite probe extra radiation at late times and thereby both scenarios. Further tests are the searches for axions at ADMX and for supersymmetric particles at the LHC.
de la Puente, Alejandro [Univ. of Notre Dame, IN (United States)
2012-05-01
In this work, I present a generalization of the Next-to-Minimal Supersymmetric Standard Model (NMSSM), with an explicit μ-term and a supersymmetric mass for the singlet superfield, as a route to alleviating the little hierarchy problem of the Minimal Supersymmetric Standard Model (MSSM). I analyze two limiting cases of the model, characterized by the size of the supersymmetric mass for the singlet superfield. The small and large limits of this mass parameter are studied, and I find that I can generate masses for the lightest neutral Higgs boson up to 140 GeV with top squarks below the TeV scale, all couplings perturbative up to the gauge unification scale, and with no need to fine tune parameters in the scalar potential. This model, which I call the S-MSSM is also embedded in a gauge-mediated supersymmetry breaking scheme. I find that even with a minimal embedding of the S-MSSM into a gauge mediated scheme, the mass for the lightest Higgs boson can easily be above 114 GeV, while keeping the top squarks below the TeV scale. Furthermore, I also study the forward-backward asymmetry in the t¯t system within the framework of the S-MSSM. For this purpose, non-renormalizable couplings between the first and third generation of quarks to scalars are introduced. The two limiting cases of the S-MSSM, characterized by the size of the supersymmetric mass for the singlet superfield is analyzed, and I find that in the region of small singlet supersymmetric mass a large asymmetry can be obtained while being consistent with constraints arising from flavor physics, quark masses and top quark decays.
Quantum groups as generalized gauge symmetries in WZNW models. Part I. The classical model
Hadjiivanov, L.; Furlan, P.
2017-07-01
Wess-Zumino-Novikov-Witten (WZNW) models over compact Lie groups G constitute the best studied class of (two dimensional, 2 D) rational conformal field theories (RCFTs). A WZNW chiral state space is a finite direct sum of integrable representations of the corresponding affine (current) algebra, and the correlation functions of primary fields are monodromy invariant combinations of left times right sector conformal blocks solving the Knizhnik-Zamolodchikov equation. However, even in this very well understood case of 2 D RCFT, the "internal" (gauge) symmetry that governs the ensuing fusion rules remains unclear. On the other hand, the canonical approach to the classical chiral WZNW theory developed by Faddeev, Alekseev, Shatashvili, Gawedzki and Falceto reveals its Poisson-Lie symmetry. After a covariant quantization, the latter gives rise to an associated quantum group symmetry which naturally requires an extension of the state space. This paper contains a review of earlier work on the subject with a special emphasis, in the case G = SU( n), on the emerging chiral "WZNW zero modes" which provide an adequate algebraic description of the internal symmetry structure of the model. Combining further left and right zero modes, one obtains a specific dynamical quantum group, the structure of its Fock representation resembling the axiomatic approach to gauge theories in which a "restricted" quantum group plays the role of a generalized gauge symmetry.
Non-linear supersymmetric {sigma}-models and their gauging in the Atiyah-Ward space-time
Carvalho, M.; Vilar, L.C.Q.; Helayel-Neto, J.A.
1995-10-01
We present a supersymmetric non-linear {sigma}-model built up in the N 1 superspace of Atiyah-ward space-time. A manifold of the Kaehler type comes out that is restricted by a a particular decomposition of the Kaehler potential. The gauging of the {sigma}-model isometries is also accomplished in superspace. (author). 20 refs.
SuperLFV: An SLHA tool for lepton flavor violating observables in supersymmetric models
Murakami, Brandon
2013-01-01
We introduce SuperLFV, a numerical tool for calculating low-energy LFV observables in the context of the minimal supersymmetric standard model (MSSM). As the Large Hadron Collider and MEG, a dedicated mu -> e gamma experiment, are presently acquiring data, there is need for tools that provide rapid discrimination of models that exhibit lepton flavor violation (LFV). SuperLFV accepts an SLHA-compliant spectrum file that contains the MSSM couplings and masses with complex phases at the supersymmetry breaking scale. In this manner, SuperLFV is compatible with but divorced from existing SLHA spectrum calculators that provides the low energy spectrum. Hence, input spectra are not confined to the LFV sources provided by established SLHA spectrum calculators. Input spectra may be generated by personal code or by hand, allowing for arbitrary models not supported by existing spectrum calculators.
Twining Genera of (0,4) Supersymmetric Sigma Models on K3
Harrison, Sarah; Paquette, Natalie M
2013-01-01
Conformal field theories with (0,4) worldsheet supersymmetry and K3 target can be used to compactify the E8xE8 heterotic string to six dimensions in a supersymmetric manner. The data specifying such a model includes an appropriate configuration of 24 gauge instantons in the E8xE8 gauge group to satisfy the constraints of anomaly cancellation. In this note, we compute twining genera - elliptic genera with appropriate insertions of discrete symmetry generators in the trace - for (0,4) theories with various instanton embeddings. We do this by constructing linear sigma models which flow to the desired conformal field theories, and using the techniques of localization. We present several examples of such twining genera which are consistent with a moonshine relating these (0,4) models to the finite simple sporadic group M24.
Aspects of the electroweak phase transition in the Minimal Supersymmetric Standard Model
Brignole, A; Quirós, Mariano; Zwirner, F
1994-01-01
We study the finite-temperature effective potential of the Minimal Supersymmetric Standard Model in the full (mA, tan(beta)) parameter space. As for the features of the electroweak phase transition, we identify two possible sources of significant differences with respect to the Standard Model: a stop sector with little supersymmetry breaking makes the phase transition more strongly first-order, whereas a light CP-odd neutral boson weakens its first-order nature. After including the leading plasma effects, T=0 radiative corrections due to top and stop loops, and the most important experimental constraints, we find that the danger of washing out any baryon asymmetry created at the electroweak scale is in general no less than in the Standard Model.
Bottom-Tau Unification in Supersymmetric Model with Anomaly-Mediation
Chigusa, So
2016-01-01
We study the Yukawa unification, in particular, the unification of the Yukawa coupling constants of $b$ and $\\tau$, in the framework of supersymmetric (SUSY) model. We concentrate on the model in which the SUSY breaking scalar masses are of the order of the gravitino mass while the gaugino masses originate from the effect of anomaly mediation and hence are one-loop suppressed relative to the gravitino mass. We perform an accurate calculation of the Yukawa coupling constants of $b$ and $\\tau$ at the grand unified theory (GUT) scale, including relevant renormalization group effects and threshold corrections. In particular, we study the renormalization group effects, taking into account the mass splittings among sfermions, gauginos, and the standard model particles. We found that the Yukawa coupling constant of $b$ at the GUT scale is about $70\\ \\%$ of that of $\\tau$ if there is no hierarchy between the sfermion masses and the gravitino mass. Our results suggest sizable threshold corrections to the Yukawa coupli...
Limits on the mass of the lightest Higgs in supersymmetric models
Masip, M; Pomarol, A
1998-01-01
In supersymmetric models extended with a gauge singlet the mass of the lightest Higgs boson has contributions proportional to the adimensional coupling $\\lambda$. In minimal scenarios, the requirement that this coupling remains perturbative up to the unification scale constrains $\\lambda$ to be smaller than $\\approx 0.7$. We study the maximum value of $\\lambda$ consistent with a perturbative unification of the gauge couplings in models containing nonstandard fields at intermediate scales. These fields appear in scenarios with gauge mediation of supersymmetry breaking. We find that the presence of extra fields can raise the maximum value of $\\lambda$ up to a 19%, increasing the limits on the mass of the lightest Higgs from 135 GeV to 155 GeV.
Higaki, Tetsutaro; Takeda, Naoyuki
2016-01-01
We study a flavor texture in a supersymmetric model with vector-like generations by using Froggatt-Nielsen mechanism. We find realistic flavor structures which reproduce the Cabbibo-Kobayashi-Maskawa matrix and fermion masses at low-energy. Furthermore, the fermionic component of the gauge singlet field becomes a candidate of dark matter, whereas the vacuum expectation value of the scalar component gives the vector-like mass. In our model, flavor physics and dark matter are explained with moderate size couplings through renormalization group flows, and the presence of dark matter supports the existence of just three generations in low energy scales. We analyze the parameter region where the current thermal relic abundance of dark matter, the Higgs boson mass and the muon $g-2$ can be explained simultaneously.
Anomaly Mediation and Fixed Point in Partially N = 2 Supersymmetric Standard Models
Yin, Wen
2016-01-01
To explain the tension between the observed Higgs boson mass and the experimental deviations from the Standard Model (SM) prediction in flavor physics, especially the experimental anomaly of the muon anomalous dipole moment (muon $g-2$), we study partially $N=2$ supersymmetric (SUSY) extensions of the SM (partially $N=2$ SSMs). In this kind of model, an $N=2$ SUSY sector is sequestered from the SUSY breaking due to $SO(2)_R$ symmetry at the tree-level. We show that the low energy physics in the $N=2$ sector is controlled by a fixed point and hence approximately UV insensitive. Moreover at this fixed point, the tachyonic slepton problem of anomaly mediation is always solved. In a concrete partially $N=2$ SSM, the muon $g-2$ anomaly is explained within the $1\\sigma$ level error with $mathcal{O}(100)$TEV cosmologically favored gravitino. We also propose some new dark matter candidates as a natural consequence of partially $N=2$ SSMs.
Stueckelberg Axions and Anomalous Abelian Extensions of the Standard Model
Morelli, Simone
2009-01-01
This thesis work analyzes basic field theoretical aspects of a class of models motivated by orientifold vacua of string theory and some of their phenomenological applications at the Large Hadron Collider. They extend the gauge structure of the Standard Model by anomalous extra U(1) symmetries, which involve Stuckelberg axions for anomaly cancellation and are accompanied by Chern-Simons interactions. In particular, these effective actions are characterized by a physical pseudoscalar (the axi-Higgs) in the CP-odd spectrum, which has the properties of a generalized Peccei-Quinn axion, with independent mass and couplings to the gauge fields. Amplitudes mediated by anomalous gauge interactions are studied at the new collider in some specific channels such as Drell-Yan and double prompt-photon and shown to be small. Finally, we address the problem of the relation between the Green-Schwarz and the Wess-Zumino mechanism(s) for anomaly cancellations in effective lagrangeans involving anomalous gauge interactions, with...
Numerical simulation of the $\\mathcal{N}=(2,2)$ Landau-Ginzburg model
Kamata, Syo
2011-01-01
The two-dimensional $\\mathcal{N}=(2,2)$ Wess-Zumino (WZ) model with a cubic superpotential is numerically studied with a momentum-cutoff regularization that preserves supersymmetry. A numerical algorithm based on the Nicolai map is employed and the resulting configurations have no autocorrelation. This system is believed to flow to an $\\mathcal{N}=(2,2)$ superconformal field theory (SCFT) in the infrared (IR) that consists of a pair of $\\mathcal{N}=2$ minimal $A_2$ models. From a finite-size scaling analysis of the susceptibility of the scalar field in the WZ model, we determine $1-h-\\Bar{h}=0.616(25)(13)$ for the conformal dimensions $h$ and $\\Bar{h}$, while $1-h-\\Bar{h}=0.666...$ for the pair of $A_2$ models. We also measure the central charge in the IR region from a correlation function between conserved supercurrents and obtain $c=1.09(14)(31)$ ($c=1$ for the $A_2$ model). These results are consistent with the conjectured emergence of $A_2$ models, and at the same time demonstrate that numerical studies c...
Schulze-Halberg, Axel, E-mail: axgeschu@iun.edu, E-mail: xbataxel@gmail.com [Department of Mathematics and Actuarial Science and Department of Physics, Indiana University Northwest, 3400 Broadway, Gary, Indiana 46408 (United States); Wang, Jie, E-mail: wangjie@iun.edu [Department of Computer Information Systems, Indiana University Northwest, 3400 Broadway, Gary, Indiana 46408 (United States)
2015-07-15
We obtain series solutions, the discrete spectrum, and supersymmetric partners for a quantum double-oscillator system. Its potential features a superposition of the one-parameter Mathews-Lakshmanan interaction and a one-parameter harmonic or inverse harmonic oscillator contribution. Furthermore, our results are transferred to a generalized Pöschl-Teller model that is isospectral to the double-oscillator system.
Bethe Ansatz for Supersymmetric Model Constructed from Uq[osp(2|2)(2)] R-Matrix
YANG Wen-Li; ZHEN Yi
2001-01-01
Using the algebraic Bethe ansatz method, we obtain the eigenvalues of transfer matrix of the supersymmetric model constructed from the R-matrix of the twisted affine superalgebra Uq[osp(2|2)(2)] in periodic boundary condition and twisted boundary condition.``
Franke, F.
1995-07-01
In this thesis after a presentation of the nonminimal supersymmetric standard model the lower mass limits for neutralinos and Higgs bosons are calculated. Then some typical scenarios for the study of the neutralino production and decay at LEP2 are constructed, for which the cross sections are calculated. (HSI)
The B ‑ L supersymmetric standard model with inverse seesaw at the large hadron collider
Khalil, S.; Moretti, S.
2017-03-01
We review the TeV scale B ‑ L extension of the minimal supersymmetric standard model (BLSSM) where an inverse seesaw mechanism of light neutrino mass generation is naturally implemented and concentrate on its hallmark manifestations at the large hadron collider (LHC).
HOU Hong-Sheng; MA Wen-Gan; ZHOU Hong; WAN Lang-Hui; JIANG Yi
2002-01-01
The top-charm associated production with the effects from both B- and L-violating interactions in TeVscale photon-proton collisions is investigated in the framework of Rp minimal supersymmetric standard model. Withinthe bounds on the relevant R-parity violating couplings, the total cross section will reach the order of 10 fb in some partsof the parameter space.
Nilpotent Symmetries of a Specific N = 2 Supersymmetric Quantum Mechanical Model: A Novel Approach
Krishna, S; Malik, R P
2013-01-01
We derive the on-shell nilpotent supersymmetric (SUSY) transformations for the N = 2 SUSY quantum mechanical model of a one (0 + 1)-dimensional free particle by exploiting the SUSY invariant restrictions on the (anti-)chiral supervariables of the SUSY theory that is defined on a (1, 2)-dimensional supermanifold (parametrized by a bosonic variable t and a pair of Grassmannian variables \\theta and \\bar \\theta with \\theta^2 = \\bar \\theta^2 = 0,\\theta \\bar \\theta + \\bar \\theta \\theta = 0). Within the framework of our novel approach, we express the Lagrangian and conserved SUSY charges in terms of the (anti-)chiral supervariables to demonstrate the SUSY invariance of the Lagrangian and nilpotency of the conserved charges in a simple manner. Our approach has the potential to be generalized to the description of other N = 2 SUSY quantum mechanical systems with physically interesting potential functions.
eμ Production in R-Parity Violating Supersymmetric Model at Hadron Colliders
无
2007-01-01
We investigate the lepton flavor violating productions (p-)p/pp → eμ + X in the framework of the R-parity violating (RPV) supersymmetric model at the Tevatron and the CERN large hadron collider (LHC). We present the total cross sections including the next-to-leading order (NLO) QCD corrections and the contribution from gluon-gluon fusion subprocess. Our numerical results show that the one-loop QCD corrections significantly increase the tree-level cross sections, and the variation of K factor is in the range between 1.28 (1.32) and 1.79 (1.58) at the Tevatron (LHC).We find that the QCD correction from the one-loop gluon-gluon fusion subprocess is remarkable at the LHC and should be taken into account.
Realizing the supersymmetric inverse seesaw model in the framework of R-parity violation
Pires, C A de S; da Silva, P S Rodrigues
2016-01-01
If, on one hand, the inverse seesaw is the paradigm of TeV scale seesaw mechanism, on the other it is a challenge to find scenarios capable of realizing it. In this work we propose a scenario, based on the framework of R-parity violation, that realizes minimally the supersymmetric inverse seesaw mechanism. In it the energy scale parameters involved in the mechanism are recognized as the vacuum expectation values of the scalars that compose the superfields $\\hat N^C$ and $\\hat S$. We develop also the scalar sector of the model and show that the Higgs mass receives a new tree-level contribution that, when combined with the standard contribution plus loop correction, is capable of attaining $125$GeV without resort to heavy stops.
Realizing the supersymmetric inverse seesaw model in the framework of R-parity violation
de S. Pires, C. A.; Rodrigues, J. G.; Rodrigues da Silva, P. S.
2016-08-01
If, on one hand, the inverse seesaw is the paradigm of TeV scale seesaw mechanism, on the other it is a challenge to find scenarios capable of realizing it. In this work we propose a scenario, based on the framework of R-parity violation, that realizes minimally the supersymmetric inverse seesaw mechanism. In it the energy scale parameters involved in the mechanism are recognized as the vacuum expectation values of the scalars that compose the singlet superfields NˆC and S ˆ . We develop also the scalar sector of the model and show that the Higgs mass receives a new tree-level contribution that, when combined with the standard contribution plus loop correction, is capable of attaining 125 GeV without resort to heavy stops.
Choi, S Y; Jang, J H; Song, H S; Park, Seong Chan
2001-01-01
We study the elastic scattering of the lightest neutralino with a nucleus in the framework of the minimal supersymmetric standard model (MSSM) with explicit flavor preserving CP violation, including the one-loop CP-violating neutral Higgs-boson mixing effects induced dominantly by the CP phases in the top and bottom (s)quark sectors. We construct the most general form of the effective Lagrangian for the neutralino-nucleus scattering in the limit of vanishing momentum transfers and then we perform a comprehensive analysis of the effects of the complex CP phases on the mass spectra of the lightest neutralino, neutral Higgs bosons and top squarks, and on the the spin-dependent and spin-independent neutralino-nucleus scattering cross section for three neucleus targets F, Si and Ge. The CP phases can reduce or enhance the neutralino-nucleus cross sections significantly, depending on the values of the real parameters in the MSSM.
Boundary effects on the supersymmetric sine-Gordon model through light-cone lattice approach
Matsui, Chihiro
2014-01-01
We discussed subspaces of the N=1 supersymmetric sine-Gordon model with Dirichlet boundaries through light-cone lattice regularization. In this paper, we showed, unlike the periodic boundary case, both of Neveu-Schwarz (NS) and Ramond (R) sectors of a superconformal field theory were obtained. Using a method of nonlinear integral equations for auxiliary functions defined by eigenvalues of transfer matrices, we found that an excitation state with an odd number of particles is allowed for a certain value of a boundary parameter even on a system consisting of an even number of sites. In a small-volume limit where conformal invariance shows up in the theory, we derived conformal dimensions of states constructed through the lattice-regularized theory. The result shows existence of the R sector, which cannot be obtained from the periodic system, while a winding number is restricted to an integer or a half-integer depending on boundary parameters.
Loop formulation of the supersymmetric nonlinear O(N) sigma model
Steinhauer, Kyle
2013-01-01
We derive the fermion loop formulation for the supersymmetric nonlinear O$(N)$ sigma model by performing a hopping expansion using Wilson fermions. In this formulation the fermionic contribution to the partition function becomes a sum over all possible closed non-oriented fermion loop configurations. The interaction between the bosonic and fermionic degrees of freedom is encoded in the constraints arising from the supersymmetry and induces flavour changing fermion loops. For $N \\ge 3$ this leads to fermion loops which are no longer self-avoiding and hence to a potential sign problem. Since we use Wilson fermions the bare mass needs to be tuned to the chiral point. For $N=2$ we determine the critical point and present boson and fermion masses in the critical regime.
Neutrino masses and b - $\\tau$ unification in the supersymmetric standard model
Vissani, F
1994-01-01
ABSTRACT: There are several indications that the Majorana masses of the right-handed neutrino components, M_R, are at the intermediate scale: M_R\\sim (10^{10}-10^{12}) GeV or even lighter. The renormalization effects due to large Yukawa couplings of neutrinos from region of momenta M_R \\ltap q \\ltap M_G are studied in the supersymmetric standard model. It is shown that neutrino renormalization effect can increase the m_b/m_\\tau ratio up to (10\\div 15)\\%. This strongly disfavours m_b-m_\\tau unification for low values of \\tan\\beta < 10 especially at large values of \\alpha_s. Lower bounds on M_R and \\tan\\beta from the b-\\tau unification condition were found. The implications of the results to the see-saw mechanism of the neutrino mass generation are discussed.
Supersymmetric classical cosmology
Escamilla-Rivera, Celia; Urena-Lopez, L Arturo
2010-01-01
In this work a supersymmetric cosmological model is analyzed in which we consider a general superfield action of a homogeneous scalar field supermultiplet interacting with the scale factor in a supersymmetric FRW model. There appear fermionic superpartners associated with both the scale factor and the scalar field, and classical equations of motion are obtained from the super-Wheeler-DeWitt equation through the usual WKB method. The resulting supersymmetric Einstein-Klein-Gordon equations contain extra radiation and stiff matter terms, and we study their solutions in flat space for different scalar field potentials. The solutions are compared to the standard case, in particular those corresponding to the exponential potential, and their implications for the dynamics of the early Universe are discussed in turn.
Ferrnion Mass Hierarchies in Singlet-Extended Minimal-Supersymmetric-Standard-Model Quivers
Salah Eddine Ennadifi; Adil Belhaj; El Hassan Saidi
2011-01-01
In the context of type-ⅡA orientifold compactifications,we discuss the fermion masses in a two-singlet-extended minimal-supersymmetric-standard-model four-stack quiver with U(3) × Sp(1) × U(1) × U(1) gauge symmetry.The corresponding effective superpotential exhibits hierarchical coupling term scales giving a partial solution to the fermion masses problem.Using the known data with upper bound neutrino masses mvτ ＜～ 2 eV,we estimate the relevant scales for the model.It has been shown that important particle physics can be realized in type-Ⅱ superstring models by using the mechanism of intersecting D-branes in orientifold compactifications.[1-6] In such compactifications,the gauge groups arise from stacks of D-branes that fill four-dimensional spacetime and wrap the three-cycles in the internal Calabi-Yau threefold.However,matter fields arise at the intersection of two different D-brane stacks in internal space and their multiplicity is given by the topological intersection numbers of the respective three-cycles.Their interactions are subject to restrictions of additional global U(1)'s exhibited by orientifold compactifications.[7-10] Stringy effects have a crucial role in this regard,as they give corrections to the superpotential by inducing the missing couplings relevant for fermion masses.This method provides an acceptable effective low energy description reproducing the standard model or some extensions.[11,12]%In the context of type-IIA orientifold compactifications, we discuss the fermion masses in a two-singlet-extended minimal-supersymmetric-standard-model four-stack quiver with U(3)×Sp(1)×U(1)×U(1) gauge symmetry. The corresponding effective superpotential exhibits hierarchical coupling term scales giving a partial solution to the fermion masses problem. Using the known data with upper bound neutrino masses mvτ≤2 eV, we estimate the relevant scales for the model.
The Supersymmetric Particle Spectrum
Barger, V; Ohmann, P
1994-01-01
We examine the spectrum of supersymmetric particles predicted by grand unified theoretical (GUT) models where the electroweak symmetry breaking is accomplished radiatively. We evolve the soft supersymmetry breaking parameters according to the renormalization group equations (RGE). The minimization of the Higgs potential is conveniently described by means of tadpole diagrams. We present complete one-loop expressions for these minimization conditions, including contributions from the matter and the gauge sectors. We concentrate on the low $\\tan \\beta$ fixed point region (that provides a natural explanation of a large top quark mass) for which we find solutions to the RGE satisfying both experimental bounds and fine-tuning criteria. We also find that the constraint from the consideration of the lightest supersymmetric particle as the dark matter of the universe is accommodated in much of parameter space where the lightest neutralino is predominantly gaugino. The supersymmetric mass spectrum displays correlations...
Quantum Dynamics of a Bulk-Boundary System
Ichinose, S; Ichinose, Shoichi; Murayama, Akihiro
2004-01-01
The quantum dynamics of a bulk-boundary theory is closely examined by the use of the background field method. As an example we take the Mirabelli-Peskin model, which is composed of 5D super Yang-Mills (bulk) and 4D Wess-Zumino (boundary). Singular interaction terms play an important role of canceling the divergences coming from the KK-mode sum. An interesting background configuration of scalar fields is found. It is a localized solution of the field equation. In this process of the vacuum search, we present a new treatment of the extra coordinate. The "supersymmetric" effective potential is obtained at the full (w.r.t. the coupling) 1-loop level. Renormalization group analysis is done. The Casimir energy is calculated and is compared with the case of the Kaluza-Klein model.
Babu, K S
2015-01-01
We present a minimal renormalizable non-supersymmetric SO(10) grand unified model with a symmetry breaking sector consisting of Higgs fields in the 54_H + 126_H + 10_H representations. This model admits a single intermediate scale associated with Pati-Salam symmetry along with a discrete parity. Spontaneous symmetry breaking, the unification of gauge couplings and proton lifetime estimates are studied in detail in this framework. Including threshold corrections self-consistently, obtained from a full analysis of the Higgs potential, we show that the model is compatible with the current experimental bound on proton lifetime. The model generally predicts an upper bound of few times 10^{35} yrs for proton lifetime, which is not too far from the present Super-Kamiokande limit of \\tau_p \\gtrsim 1.29 \\times 10^{34} yrs. With the help of a Pecci-Quinn symmetry and the resulting axion, the model provides a suitable dark matter candidate while also solving the strong CP problem. The intermediate scale, M_I \\approx (10...
Planarizable Supersymmetric Quantum Toboggans
Miloslav Znojil
2011-02-01
Full Text Available In supersymmetric quantum mechanics the emergence of a singularity may lead to the breakdown of isospectrality between partner potentials. One of the regularization recipes is based on a topologically nontrivial, multisheeted complex deformations of the line of coordinate x giving the so called quantum toboggan models (QTM. The consistent theoretical background of this recipe is briefly reviewed. Then, certain supersymmetric QTM pairs are shown exceptional and reducible to doublets of non-singular ordinary differential equations a.k.a. Sturm-Schrödinger equations containing a weighted energy E→EW(x and living in single complex plane.
Koehn, Michael
2015-01-01
In supersymmetric theories, topological defects can have nontrivial behaviors determined purely by whether or not supersymmetry is restored in the defect core. A well-known example of this is that some supersymmetric cosmic strings are automatically superconducting, leading to important cosmological effects and constraints. We investigate the impact of nontrivial kinetic interactions, present in a number of particle physics models of interest in cosmology, on the relationship between supersymmetry and supercurrents on strings. We find that in some cases it is possible for superconductivity to be disrupted by the extra interactions.
Renormalization group running of fermion observables in an extended non-supersymmetric SO(10) model
Meloni, Davide; Ohlsson, Tommy; Riad, Stella
2017-03-01
We investigate the renormalization group evolution of fermion masses, mixings and quartic scalar Higgs self-couplings in an extended non-supersymmetric SO(10) model, where the Higgs sector contains the 10 H, 120 H, and 126 H representations. The group SO(10) is spontaneously broken at the GUT scale to the Pati-Salam group and subsequently to the Standard Model (SM) at an intermediate scale M I. We explicitly take into account the effects of the change of gauge groups in the evolution. In particular, we derive the renormalization group equations for the different Yukawa couplings. We find that the computed physical fermion observables can be successfully matched to the experimental measured values at the electroweak scale. Using the same Yukawa couplings at the GUT scale, the measured values of the fermion observables cannot be reproduced with a SM-like evolution, leading to differences in the numerical values up to around 80%. Furthermore, a similar evolution can be performed for a minimal SO(10) model, where the Higgs sector consists of the 10 H and 126 H representations only, showing an equally good potential to describe the low-energy fermion observables. Finally, for both the extended and the minimal SO(10) models, we present predictions for the three Dirac and Majorana CP-violating phases as well as three effective neutrino mass parameters.
A minimal supersymmetric model of particle physics and the early universe
Buchmueller, W.; Domcke, V.; Kamada, K. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Schmitz, K. [Tokyo Univ., Kashiwa (Japan). Kavli IPMU, TODIAS
2013-11-15
We consider a minimal supersymmetric extension of the Standard Model, with right-handed neutrinos and local B-L, the difference between baryon and lepton number, a symmetry which is spontaneously broken at the scale of grand unification. To a large extent, the parameters of the model are determined by gauge and Yukawa couplings of quarks and leptons. We show that this minimal model can successfully account for the earliest phases of the cosmological evolution: Inflation is driven by the energy density of a false vacuum of unbroken B-L symmetry, which ends in tachyonic preheating, i.e. the decay of the false vacuum, followed by a matter dominated phase with heavy B-L Higgs bosons. Nonthermal and thermal processes produce an abundance of heavy neutrinos whose decays generate primordial entropy, baryon asymmetry via leptogenesis and dark matter consisting of gravitinos or nonthermal WIMPs. The model predicts relations between neutrino and superparticle masses and a characteristic spectrum of gravitational waves.
The structure of N=2 supersymmetric nonlinear sigma models in AdS_4
Butter, Daniel
2011-01-01
We present a detailed study of the most general N=2 supersymmetric sigma models in four-dimensional anti-de Sitter space AdS_4 formulated in terms of N=1 chiral superfields. The target space is demonstrated to be a non-compact hyperkahler manifold restricted to possess a special Killing vector field which generates an SO(2) group of rotations on the two-sphere of complex structures and necessarily leaves one of them invariant. All hyperkahler cones, that is the target spaces of N=2 superconformal sigma models, prove to possess such a vector field that belongs to the Lie algebra of an isometry group SU(2) acting by rotations on the complex structures. A unique property of the N=2 sigma models constructed is that the algebra of OSp(2|4) transformations closes off the mass shell. We uncover the underlying N=2 superfield formulation for the N=2 sigma models constructed and compute the associated N=2 supercurrent. We give a special analysis of the most general systems of self-interacting N=2 tensor multiplets in A...
Supersymmetric model for dark matter and baryogenesis motivated by the recent CDMS result.
Allahverdi, Rouzbeh; Dutta, Bhaskar; Mohapatra, Rabindra N; Sinha, Kuver
2013-08-02
We discuss a supersymmetric model for cogenesis of dark and baryonic matter where the dark matter (DM) has mass in the 8-10 GeV range as indicated by several direct detection searches, including most recently the CDMS experiment with the desired cross section. The DM candidate is a real scalar field. Two key distinguishing features of the model are the following: (i) in contrast with the conventional weakly interacting massive particle dark matter scenarios where thermal freeze-out is responsible for the observed relic density, our model uses nonthermal production of dark matter after reheating of the Universe caused by moduli decay at temperatures below the QCD phase transition, a feature which alleviates the relic overabundance problem caused by small annihilation cross section of light DM particles and (ii) baryogenesis occurs also at similar low temperatures from the decay of TeV scale mediator particles arising from moduli decay. A possible test of this model is the existence of colored particles with TeV masses accessible at the LHC.
Khoury, Justin; Ovrut, Burt A
2011-01-01
Galileon theories are of considerable interest since they allow for stable violations of the null energy condition. Since such violations could have occurred during a high-energy regime in the history of our universe, we are motivated to study supersymmetric extensions of these theories. This is carried out in this paper, where we construct generic classes of N=1 supersymmetric Galileon Lagrangians. They are shown to admit non-equivalent stress-energy tensors and, hence, vacua manifesting differing conditions for violating the null energy condition. The temporal and spatial fluctuations of all component fields of the supermultiplet are analyzed and shown to be stable on a large number of such backgrounds. In the process, we uncover a surprising connection between conformal Galileon and ghost condensate theories, allowing for a deeper understanding of both types of theories.
Mambrini, Y.; Moultaka, G.
2001-01-01
We reconsider the Infrared Quasi Fixed Points which were studied recently in the literature in the context of the Baryon and Lepton number violating Minimal Supersymmetric Standard Model (hep-ph/0011274). The complete analysis requires further care and reveals more structure than what was previously shown. The formalism we develop here is quite general, and can be readily applied to a large class of models.
Supersymmetric Quantum Mechanics and Topology
Muhammad Abdul Wasay
2016-01-01
Full Text Available Supersymmetric quantum mechanical models are computed by the path integral approach. In the β→0 limit, the integrals localize to the zero modes. This allows us to perform the index computations exactly because of supersymmetric localization, and we will show how the geometry of target space enters the physics of sigma models resulting in the relationship between the supersymmetric model and the geometry of the target space in the form of topological invariants. Explicit computation details are given for the Euler characteristics of the target manifold and the index of Dirac operator for the model on a spin manifold.
The Tachyon in a Linear Expanding Universe
Behrndt, K.
1992-01-01
We investigate the tachyon coupling in a static Robertson--Walker like metric background. For a tachyon and dilaton field which are only time dependent one can rewrite this model as a SU(2) Wess--Zumino--Witten model and a scalar Feigin--Fuchs theory. In this case the restriction to a real exponential tachyon field fixes the level $k$ of the Wess--Zumino--Witten model. For a spatially dependent tachyon the world radius and the dilaton are quantized in terms of $k$ and the tachyon by two integ...
Gravitino and scalar {tau}-lepton decays in supersymmetric models with broken R-parity
Hajer, Jan
2010-06-15
Mildly broken R-parity is known to provide a solution to the cosmological gravitino problem in supergravity extensions of the Standard Model. In this work we consider new effects occurring in the R-parity breaking Minimal Supersymmetric Standard Model including right-handed neutrino superfields. We calculate the most general vacuum expectation values of neutral scalar fields including left- and right-handed scalar neutrinos. Additionally, we derive the corresponding mass mixing matrices of the scalar sector. We recalculate the neutrino mass generation mechanisms due to right- handed neutrinos as well as by cause of R-parity breaking. Furthermore, we obtain a, so far, unknown formula for the neutrino masses for the case where both mechanisms are effective. We then constrain the couplings to bilinear R-parity violating couplings in order to accommodate R-parity breaking to experimental results. In order to constrain the family structure with a U(1){sub Q} flavor symmetry we furthermore embed the particle content into an SU(5) Grand Unified Theory. In this model we calculate the signal of decaying gravitino dark matter as well as the dominant decay channel of a likely NLSP, the scalar {tau}-lepton. Comparing the gravitino signal with results of the Fermi Large Area Telescope enables us to find a lower bound on the decay length of scalar {tau}-leptons in collider experiments. (orig.)
Higgs mass and right-handed sneutrino WIMP in a supersymmetric 3-3-1 model
Pires, C A de S; Santos, A C O; Siqueira, Clarissa
2016-01-01
This work deals with right handed sneutrino as thermal cold dark matter candidate. This scalar emerges in a supersymmetric version of $SU(3)_c \\otimes SU(3)_L \\otimes U(1)_X$ gauge model where right handed neutrinos are a natural component of leptonic chiral scalar supermultiplets. We first consider the issue of a $125$~GeV Higgs boson mass in this model, showing that constraints on stop mass and trilinear soft coupling are considerably alleviated compared to MSSM. Then we investigate the region of parameter space that is consistent with right handed sneutrino as thermal cold dark matter, under the light of Planck results on the relic abundance and direct detection from LUX experiment. This sneutrino mainly annihilates through an extra neutral gauge boson, $Z^\\prime$, and Higgs exchange, so that the physics of dark matter is somewhat related to the parameters determining Higgs and $Z^\\prime$ masses. We then obtain that right handed sneutrino in this model must be heavier than $400$~GeV to conform with Planck ...
Krishna, S., E-mail: skrishna.bhu@gmail.com [Physics Department, Centre of Advanced Studies, Banaras Hindu University (BHU), Varanasi-221 005 (India); Shukla, A., E-mail: ashukla038@gmail.com [Physics Department, Centre of Advanced Studies, Banaras Hindu University (BHU), Varanasi-221 005 (India); Malik, R.P., E-mail: rpmalik1995@gmail.com [Physics Department, Centre of Advanced Studies, Banaras Hindu University (BHU), Varanasi-221 005 (India); DST-CIMS, Faculty of Science, BHU-Varanasi-221 005 (India)
2014-12-15
Using the supersymmetric (SUSY) invariant restrictions on the (anti-)chiral supervariables, we derive the off-shell nilpotent symmetries of the general one (0+1)-dimensional N=2 SUSY quantum mechanical (QM) model which is considered on a (1, 2)-dimensional supermanifold (parametrized by a bosonic variable t and a pair of Grassmannian variables θ and θ-bar with θ{sup 2}=(θ-bar){sup 2}=0,θ(θ-bar)+(θ-bar)θ=0). We provide the geometrical meanings to the two SUSY transformations of our present theory which are valid for any arbitrary type of superpotential. We express the conserved charges and Lagrangian of the theory in terms of the supervariables (that are obtained after the application of SUSY invariant restrictions) and provide the geometrical interpretation for the nilpotency property and SUSY invariance of the Lagrangian for the general N=2 SUSY quantum theory. We also comment on the mathematical interpretation of the above symmetry transformations. - Highlights: • A novel method has been proposed for the derivation of N=2 SUSY transformations. • General N=2 SUSY quantum mechanical (QM) model with a general superpotential, is considered. • The above SUSY QM model is generalized onto a (1, 2)-dimensional supermanifold. • SUSY invariant restrictions are imposed on the (anti-)chiral supervariables. • Geometrical meaning of the nilpotency property is provided.
Lepton Flavour Violation in a Supersymmetric Model with A4 Flavour Symmetry
Feruglio, Ferruccio; Lin, Yin; Merlo, Luca
2009-01-01
We compute the branching ratios for mu-> e gamma, tau-> mu gamma and tau -> e gamma in a supersymmetric model invariant under the flavour symmetry group A4 X Z3 X U(1)_{FN}, in which near tri-bimaximal lepton mixing is naturally predicted. At leading order in the small symmetry breaking parameter u, which is of the same order as the reactor mixing angle theta_{13}, we find that the branching ratios generically scale as u^2. Applying the current bound on the branching ratio of mu -> e gamma shows that small values of u or tan(beta) are preferred in the model for mass parameters m_{SUSY} and m_{1/2} smaller than 1000 GeV. The bound expected from the on-going MEG experiment will provide a severe constraint on the parameter space of the model either enforcing u approx 0.01 and small tan(beta) or m_{SUSY} and m_{1/2} above 1000 GeV. In the special case of universal soft supersymmetry breaking terms in the flavon sector a cancellation takes place in the amplitudes and the branching ratios scale as u^4, allowing for...
Precise predictions for Higgs physics in the next-to-minimal supersymmetric standard model (NMSSM)
Drechsel, Peter
2016-08-15
Within this thesis a precise mass-prediction for the Higgs fields of the Next-to-Minimal Supersymmetric Standard Model (NMSSM) is obtained with Feynman-diagrammatic methods. The results are studied numerically for sample scenarios that are in agreement with current New Physics searches at the LHC. Furthermore a comparison between the obtained results and different calculations is performed as a first step in order to obtain an estimation for the theoretical uncertainties of the Higgs-mass prediction in the NMSSM. The precise mass-prediction includes the full NMSSM one-loop corrections supplemented with the dominant and sub-dominant two-loop corrections within the Minimal Supersymmetric Standard Model (MSSM). These include contributions at the orders O(α{sub t}α{sub s}, α{sub b}α{sub s}, α{sub t}{sup 2}, α{sub t}α{sub b}), as well as a resummation of leading and subleading logarithms from the top/scalar top sector. Higher-order corrections are essential for the NMSSM in order to provide a Higgs particle that is consistent with the available data, including the observed neutral, CP-even Higgs field with a mass of about 125 GeV. We explored the validity of the applied approximation at the two-loop level and found that it is reliable for a wide range of scenarios within the NMSSM. This is especially true for the mass of the observed (MS)SM-like Higgs field. The result of this work will be included in a future extension of the program FeynHiggs. We also compared our results with the program NMSSMCalc that also performs a Feynman-diagrammatic calculation of the Higgs-masses with a slightly different renormalization scheme. The comparison reveals that for the mass of the (MS)SM-like Higgs field the genuine NMSSM-effects induced by the choice of the renormalization scheme are by far minor compared to similar effects observed in the MSSM.
Constraint on the scale-unifying supersymmetric preon model from K{sup 0} - anti-K{sup 0} mixing
Kim, Jongbae [Department of Physics, University of Maryland, College Park, MD 20742 (United States); Research Department, ETRI, Yusong PO Box 106, Taejon 305-600 (Korea, Republic of)
1997-06-01
We study the flavour changing neutral current process in K{sup 0} - anti-K{sup 0} mixing in the supersymmetric preon model (SPM). Compared to the minimal supersymmetric standard model (MSSM), one distinguishing feature of K{sup 0} - anti-K{sup 0} mixing in the SPM is that there are new contributions from box diagrams involving two vector-like families of quarks and their supersymmetric (SUSY) partners with masses of order 1 TeV. Another special feature of the process in the SPM, in contrast to the MSSM, is that left-right squark (q-tilde{sub L} - q-tilde{sub R}) mixing is highly suppressed owing to symmetries of the underlying model. We calculate the SUSY box diagrams for K{sup 0} - anti-K{sup 0} mixing for the case of the SPM, using observed K{sup 0} - anti-K{sup 0} mass splitting, and obtain the constraint of ({delta}m-tilde{sub ds}{sup 2}/m-tilde{sub q}{sup 2}){sup 2} < or approx. 1.44x10{sup -5} on the squark mass degeneracy in the model. This upper limit is smaller by about a factor of 3.6 than the corresponding limit for the MSSM. The difference arises because of the absence of (q-tilde{sub L} - q-tilde{sub R}) mixing in the preon model. (author)
Yukawa Unified Supersymmetric SO(10) Model Cosmology, Rare Decays and Collider Searches
Baer, Howard W; Díaz, M A; Ferrandis, J; Mercadante, P G; Quintana, P; Tata, Xerxes; Baer, Howard; Brhlik, Michal; Diaz, Marco A.; Ferrandis, Javier; Mercadante, Pedro; Quintana, Pam; Tata, Xerxes
2001-01-01
It has recently been pointed out that viable sparticle mass spectra can be generated in Yukawa unified SO(10) supersymmetric grand unified models consistent with radiative breaking of electroweak symmetry. Model solutions are obtained only if $\\tan\\beta \\sim 50$, $\\mu <0$ and positive $D$-term contributions to scalar masses from SO(10) gauge symmetry breaking are used. In this paper, we attempt to systematize the parameter space regions where solutions are obtained. We go on to calculate the relic density of neutralinos as a function of parameter space. No regions of the parameter space explored were actually cosmologically excluded, and very reasonable relic densities were found in much of parameter space. Direct neutralino detection rates could exceed 1 event/kg/day for a $^{73}$Ge detector, for low values of GUT scale gaugino mass $m_{1/2}$. We also calculate the branching fraction for $b\\to s \\gamma$ decays, and find that it is beyond the 95% CL experimental limits in much, but not all, of the paramete...
Natural origin of inflation within a class of supersymmetric preon models
Cveti, Mirjam; Hübsch, Tristan; Pati, Jogesh C.; Stremnitzer, Hanns
1989-08-01
Derivation of a desired potential for implementing the idea of new inflation from an underlying theory of particle physics has so far remained a challenging task in that it requires unusually small quartic coupling (~10-13+/-1) and an even smaller mass term for the relevant field (the inflaton) in units of its true vacuum expectation value. It is shown that a class of viable locally supersymmetric preon models naturally give rise to the desired potential for a composite field ΔR commonly used as a Higgs field to break left-right symmetry and B-L, so that ΔR can serve as the inflaton. We show that both the quartic coupling and the mass of ΔR vanish in the limit of supersymmetry, U(1)X, U(1)V and gauge invariance. Radiative corrections, in the presence of soft supersymmetry-breaking mass terms, which arise dynamically in the model, give rise to a miniscule quartic coupling and a negligible mass for ΔR, just as desired. This turns out to be the case in spite of the fact that ΔR is a gauge nonsinglet.
Explanation of the masses of quarks and leptons in a supersymmetric preon model
Jongbae Kim [Department of Physics, University of Maryland, College Park, MD 20742 (United States); Research Department, ETRI, Yusong PO Box 106, Taejon 305-600 (Korea, Republic of)
1998-10-01
We have studied whether the radiative effects including gauge and Yukawa interaction corrections can improve the phenomenological consequences on the masses of quarks and leptons in the supersymmetric preon model. Our study shows that pure renormalization effects in the region from the metacolour scale to the electroweak scale produce quark-lepton distinction within a given family. They cannot, however, produce the desired up-down distinction or the expected quark-lepton asymmetry in the effective hierarchy parameter p{sup 2}/4 of the up, down and lepton sectors. It also shows that the pure radiative corrections cannot explain the 'fine structure' effects exhibited by ((m{sub s})/m{sub c})1 GeV > ((m{sub b})/m{sub s})L GeV > ((m{sub r})/m{sub {mu}})1 GeV. These lead us to conclude that the symmetry structure of the preon theory cannot strictly respect left-right, up-down and quark-lepton symmetries near and below the Planck scale. This subsequently implies the SU(3){sup C}xSU(2){sub L}xU(1){sub r} symmetry both as regards unification of couplings near the Planck scale in the model and as regards its possible origin from a superstring theory. (author)
Explanation of the masses of quarks and leptons in a supersymmetric preon model
Kim, Jongbae
1998-10-01
We have studied whether the radiative effects including gauge and Yukawa interaction corrections can improve the phenomenological consequences on the masses of quarks and leptons in the supersymmetric preon model. Our study shows that pure renormalization effects in the region from the metacolour scale to the electroweak scale produce quark-lepton distinction within a given family. They cannot, however, produce the desired up-down distinction or the expected quark-lepton asymmetry in the effective hierarchy parameter 0954-3899/24/10/006/img1 of the up, down and lepton sectors. It also shows that the pure radiative corrections cannot explain the `fine structure' effects exhibited by 0954-3899/24/10/006/img2. These lead us to conclude that the symmetry structure of the preon theory cannot strictly respect left-right, up-down and quark-lepton symmetries near and below the Planck scale. This subsequently implies the 0954-3899/24/10/006/img3 symmetry both as regards unification of couplings near the Planck scale in the model and as regards its possible origin from a superstring theory.
Analysis of the R-symmetric supersymmetric models including quantum corrections
Kotlarski, Wojciech
2016-01-01
We study the Minimal R-symmetric Supersymmetric Standard Model (MRSSM) at the quantum level. The thesis consists of two parts. First one treats about the electroweak sector of the model. Among others, it identifies the parameter region allowed by the electroweak precision observables. Since the MRSSM contains an $SU(2)_L$-triplet with a non-zero vacuum expectation value the emphasis is put on the calculation of the $W$ boson mass. To that end, a full one-loop calculation of $m_W$ augmented with the leading two-loop SM result is presented. The region is then checked against the measurement of the Higgs boson mass. For this, the full one-loop and leading two-loop corrections to the Higgs boson mass in the MRSSM are calculated. Devised benchmark points, consistent with both of these observables, are shown to fulfill also a number of additional experimental constraints like properties of the Higgs boson(s), $b$-physics observables and vacuum stability. Correlating all of these observables allows to put bounds on ...
Novel symmetries in an interacting 𝒩 = 2 supersymmetric quantum mechanical model
Krishna, S.; Shukla, D.; Malik, R. P.
2016-07-01
In this paper, we demonstrate the existence of a set of novel discrete symmetry transformations in the case of an interacting 𝒩 = 2 supersymmetric quantum mechanical model of a system of an electron moving on a sphere in the background of a magnetic monopole and establish its interpretation in the language of differential geometry. These discrete symmetries are, over and above, the usual three continuous symmetries of the theory which together provide the physical realizations of the de Rham cohomological operators of differential geometry. We derive the nilpotent 𝒩 = 2 SUSY transformations by exploiting our idea of supervariable approach and provide geometrical meaning to these transformations in the language of Grassmannian translational generators on a (1, 2)-dimensional supermanifold on which our 𝒩 = 2 SUSY quantum mechanical model is generalized. We express the conserved supercharges and the invariance of the Lagrangian in terms of the supervariables (obtained after the imposition of the SUSY invariant restrictions) and provide the geometrical meaning to (i) the nilpotency property of the 𝒩 = 2 supercharges, and (ii) the SUSY invariance of the Lagrangian of our 𝒩 = 2 SUSY theory.
Phenomenology of the lightest Higgs boson in the Next-to-Minimal Supersymmetric Standard Model
Jia-Wei, Fan; Yu-Qiao, Shen; Guo-Ming, Chen; He-Sheng, Chen; Gascon-Shotkin, S; Lethuillier, M; Sgandurra, L
2013-01-01
The CMS and ATLAS experiments at the LHC announced an excess with mass at about 125 $GeV/c^{2}$ in the search of Standard Model Higgs with mainly the final decaying state $\\gamma\\gamma$ and $ZZ$ to four leptons. Considering the recent results on the Higgs searching from the LHC, we study the phenomenology of the lightest Higgs boson $h_{1}$ in the Next-to-Minimal Supersymmetric Standard Model by restricting the second lightest Higgs boson $h_{2}$ to be the observed 125 $GeV/c^{2}$ state. We perform a scan over the relevant NMSSM parameter space that is favoured by low fine-tuning considerations. Moreover, we also take into account the experimental constraints from direct searches, $b$-physics, relic density and anomalous magnetic moment of the muon measurements as well as the theoretical considerations in our specific scan. We find that the signal rate in the two photons final state for NMSSM Higgs boson $h_{1}$ with the mass range from about 80 $GeV/c^{2}$ to about 122 $GeV/c^{2}$ can be enhanced by a factor...
Source of Kerr-Newman solution as supersymmetric bag model: 50 years of the problem
Burinskii, A.
The ultra extreme Kerr-Newman (KN) solution(a = J/m >> m) produces the gravitational and EM fields of the electron. It has a naked singular ring - a topological defect which may be regularized by a solitonic source forming the pseudo-vacuum bubble filled by Higgs condensate in a supersymmetric superconducting state. Structure and stability of this source is determined by Bogomolnyi equations as a BPS-saturated soliton. The Principal Null Congruences of the KN solution determine consistent embedding of the Dirac equation, which acquires the mass from the Higgs condensate inside the soliton, indicating that this soliton forms a bag model. Shape of this bag is unambiguously determined by BPS-bound. The bag turns out to be flexible and takes the form of a very thin disk, which is completed by a ring-string along its sharp boundary. The ring-string traveling waves generate extra deformations of the bag creating a circulating singular pole. Bag model of the KN source integrates the dressed and pointlike electron in a bag-string-quark system, which removes the conflict between gravity and the point-like electron of the Dirac theory.
A mini review on CP-violating minimal supersymmetric Standard Model Higgs
AMIT CHAKRABORTY; DILIP KUMAR GHOSH
2016-09-01
We discuss the present status of the Higgs sector of the CP-violating minimal supersymmetric Standard Model (CPVMSSM). In the Standard Model (SM) of particle physics, the only source of CP violation is the complex phase in the Cabibbo–Kobayashi–Maskawa (CKM) matrix. By now we all know that this singlephase is not large enough to explain the observed baryon asymmetry of our Universe. Hence, one require additional sources of CP violation. The MSSM with several complex phases is one such scenario. The tree-level CP invariance of the MSSM Higgs potential is broken at one-loop level in the presence of complex phases in the MSSM Lagrangian. The presence of these additional phases modifies Higgs masses, mixings and couplings significantly. These additional phases have non-trivial impact on several low-energy observables; like the electric dipole moments (EDMs) of atoms and molecules, the CP asymmetry in rare b-decays etc. We first present a brief outline of the CPVMSSM Higgs sector, and then discuss the current limits/bounds obtained from the measurementsof several low-energy observables. We also comment on the current bounds coming from the high-energy collider experiments, specially the Large Electron Positron (LEP) Collider and the ongoing Large Hadron Collider (LHC) at the CERN.
Asymmetric dark matter from spontaneous cogenesis in the supersymmetric standard model
Kamada, Kohei [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Yamaguchi, Masahide [Tokyo Institute of Technology (Japan). Dept. of Physics
2012-01-15
The observational relation between the density of baryon and dark matter in the Universe, {omega}{sub DM}/{omega}{sub B}{approx_equal}5, is one of the most difficult problems to solve in modern cosmology. We discuss a scenario that explains this relation by combining the asymmetric dark matter scenario and the spontaneous baryogenesis associated with the flat direction in the supersymmetric standard model. A part of baryon asymmetry is transferred to charge asymmetry D that dark matter carries, if a symmetry violating interaction that works at high temperature breaks not only B-L but also D symmetries simultaneously. In this case, the present number density of baryon and dark matter can be same order if the symmetric part of dark matter annihilates sufficiently. Moreover, the baryon number density can be enhanced as compared to that of dark matter if another B-L violating interaction is still in thermal equilibrium after the spontaneous genesis of dark matter, which accommodates a TeV scale asymmetric dark matter model. (orig.)
Search for Mono-Higgs Signals at the LHC in the B-L Supersymmetric Standard Model
Abdallah, W; Khalil, S; Moretti, S
2016-01-01
We study mono-Higgs signatures emerging in the $B-L$ supersymmetric standard model induced by new channels not present in the minimal supersymmetric standard model, i.e., via topologies in which the mediator is either a heavy $Z'$, with mass of ${\\cal O}(2~{\\rm TeV})$, or an intermediate $h'$ (the lightest CP-even Higgs state of $B-L$ origin), with mass of ${\\cal O}(0.2~{\\rm TeV})$. The mono-Higgs probe considered is the SM-like Higgs state recently discovered at the large hadron collider, so as to enforce its mass reconstruction for background reduction purposes. With this in mind, its two cleanest signatures are selected: $\\gamma\\gamma$ and $ZZ^*\\to 4l$ ($l=e,~\\mu$). We show how both of these can be accessed with foreseen energy and luminosity options using a dedicated kinematic analysis performed in presence of partonic, showering, hadronisation and detector effects.
HOUHong－sheng; MAWen－Gan; 等
2002-01-01
The top-charm associated production with the effects from both B-and L-violating interactions in TeV scale photon-proton collisions is investigated in the framework of Rp minimal supersymmetric standard model.Within the bounds on the relevant R-parity violating couplings,the total cross section will reach the order or 10 fb in some parts of the parameter space.
Ma, E
1994-01-01
In the minimal supersymmetric standard model, the Higgs sector has two unknown parameters, usually taken to be $\\tan \\beta \\equiv v_2/v_1$ and $m_A$, the mass of its one physical pseudoscalar particle. By minimizing the minimum of the Higgs potential along a certain direction in parameter space, it is shown that $m_A = M_Z$ + radiative correction, and if one further plausible assumption is made, $\\tan \\beta > \\sqrt 3$.
Choi, S Y; Song, W Y
2000-01-01
We investigate the associated production of neutralinos $e^+e^-\\to\\tilde{\\chi}^0_1\\tilde{\\chi}^0_2$ accompanied by the neutralino leptonic decay $\\tilde{\\chi}^0_2\\to\\tilde{\\chi}^0_1 \\ell^+\\ell^-$, taking into account initial beam polarization and production-decay spin correlations in the minimal supersymmetric standard model with general CP phases but without generational mixing in the slepton sector. The stringent constraints from the electron EDM on the CP phases are also included in the discussion. Initial beam polarizations lead to three CP-even distributions and one CP-odd distribution, which can be studied independently of the details of the neutralino decays. We find that the production cross section and the branching fractions of the leptonic neutralino decays are very sensitive to the CP phases. In addition, the production-decay spin correlations lead to several CP-even observables such as lepton invariant mass distribution, and lepton angular distribution, and one interesting T-odd (CP-odd) triple p...
New constraints on neutralino dark matter in the supersymmetric standard model
Kelley, S; Nanopoulos, Dimitri V; Pois, H; Yuan, K
1993-01-01
We investigate the prospects for neutralino dark matter within the Supersymmetric Standard Model (SSM) including the constraints from universal soft supersymmetry breaking and radiative breaking of the electroweak symmetry. The latter is enforced by using the one-loop Higgs effective potential which automatically gives the one-loop corrected Higgs boson masses. We perform an exhaustive search of the allowed five-dimensional parameter space and find that the neutralino relic abundance $\\Omega_\\chi h^2_0$ depends most strongly on the ratio $\\xi_0\\equiv m_0/m_{1/2}$. For $\\xi_0\\gg1$ the relic abundance is almost always much too large, whereas for $\\xi_0\\ll1$ the opposite occurs. For $\\xi_0\\sim1$ there are wide ranges of the remaining parameters for which $\\Omega_\\chi\\sim1$. We also determine that $m_{\\tilde q}\\gsim250\\GeV$ and $m_{\\tilde l}\\gsim100\\GeV$ are necessary in order to possibly achieve $\\Omega_\\chi\\sim1$. These lower bounds are much weaker than the corresponding ones derived previously when radiative b...
Implications of Yukawa unification for the Higgs sector in supersymmetric grand-unified models
Langacker, P G; Paul Langacker; Nir Polonsky
1994-01-01
The SU(5) unification-scale relation h_b=h_tau between the b and tau Yukawa couplings severely constrains tan beta and m_t (even more so if h_t=h_b= h_tau holds) in supersymmetric models. We examine the implications of these constraints for the Higgs sector assuming universal soft breaking terms, and emphasize that both of these relations impose unique characteristics in terms of symmetries and of the spectrum. We further study the tan beta near 1 scenario, which is suggested by h_b=h_tau, and, in particular, the loop- induced mass of the light Higgs boson. We compare the effective potential and renormalization group methods and stress the two-loop ambiguities in the calculation of the mass. These and a large enhancement to the loop correction due to t-scalar left-right mixing considerably weaken the upper bound. Nevertheless, we find that for this scenario the Higgs boson is probably lighter than 110 GeV, and typically lighter than 100 GeV. Thus, it is in the mass range that may be relevant for LEPII. Our nu...
Nearly Supersymmetric Dark Atoms
Behbahani, Siavosh R.; Jankowiak, Martin; /SLAC /Stanford U., ITP; Rube, Tomas; /Stanford U., ITP; Wacker, Jay G.; /SLAC /Stanford U., ITP
2011-08-12
Theories of dark matter that support bound states are an intriguing possibility for the identity of the missing mass of the Universe. This article proposes a class of models of supersymmetric composite dark matter where the interactions with the Standard Model communicate supersymmetry breaking to the dark sector. In these models supersymmetry breaking can be treated as a perturbation on the spectrum of bound states. Using a general formalism, the spectrum with leading supersymmetry effects is computed without specifying the details of the binding dynamics. The interactions of the composite states with the Standard Model are computed and several benchmark models are described. General features of non-relativistic supersymmetric bound states are emphasized.
Grab, Sebastian
2009-08-15
The most widely studied supersymmetric scenario is the minimal supersymmetric standard model (MSSM) with more than a hundred free parameters. However for detailed phenomenological studies, the minimal supergravity (mSUGRA) model, a restricted and well-motivated framework for the MSSM, is more convenient. In this model, lepton- and baryon-number violating interactions are suppressed by a discrete symmetry, R-parity or proton-hexality, to keep the proton stable. However, it is sufficient to forbid only lepton- or baryon-number violation. We thus extend mSUGRA models by adding a proton-hexality violating operator at the grand unification scale. This can change the supersymmetric spectrum leading on the one hand to a sneutrino, smuon or squark as the lightest supersymmetric particle (LSP). On the other hand, a wide parameter region is reopened, where the scalar tau (stau) is the LSP. We investigate in detail the conditions leading to non-neutralino LSP scenarios. We take into account the restrictions from neutrino masses, the muon anomalous magnetic moment, b{yields}s{gamma}, and other precision measurements. We furthermore investigate existing restrictions from direct searches at LEP, the Tevatron, and the CERN p anti p collider. It is vital to know the nature of the LSP, since supersymmetric particles normally cascade decay down to the LSP at collider experiments. We present typical LHC signatures for sneutrino LSP scenarios. Promising signatures are high-p{sub T} muons and jets, like-sign muon events and detached vertices from long lived taus. We also classify the stau LSP decays and describe their dependence on the mSUGRA parameters. We then exploit our results for resonant single slepton production at the LHC. We find novel signatures with like-sign muon and three- and four-muon final states. Finally, we perform a detailed analysis for single slepton production in association with a single top quark. We show that the signal can be distinguished from the background
A Fermi surface model for large supersymmetric AdS{sub 5} black holes
Berkooz, Micha [Department of Particle Physics, Weizmann Institute of Science, Rehovot 76100 (Israel); Reichmann, Dori [Department of Particle Physics, Weizmann Institute of Science, Rehovot 76100 (Israel); Simon, Joan [David Rittenhouse Laboratories, University of Pennsylvania, Philadelphia, PA 19104 (United States)
2007-01-15
We identify a large family of 1/16 BPS operators in N = 4 SYM that qualitatively reproduce the relations between charge, angular momentum and entropy in regular supersymmetric AdS{sub 5} black holes when the main contribution to their masses is given by their angular momentum.
Supersymmetric $U(1)_{Y^{\\prime}}\\otimes U(1)_{B-L}$ extension of the standard model
Montero, J C; Rodriguez, M C; Sánchez-Vega, B L
2016-01-01
We build a supersymmetric version of the model with $SU(3)_C\\otimes SU(2)_L\\otimes U(1)_{Y^\\prime}\\otimes U(1)_{B-L}$ gauge symmetry, where $Y^\\prime$ is a new charge and $B$ and $L$ are the usual baryonic and leptonic numbers. The model has three right-handed neutrinos with identical $B-L$ charges, and can accommodate all fermion masses at the tree level. In particular, the type-I seesaw mechanism is implemented for the generation of the active neutrino masses. We also obtain the mass spectra of all the scalar sectors and the flat directions allowed by the model.
Are supersymmetric models with minimal particle content under tension for testing at LHC?
Samanta, Abhijit; Mandal, Sujoy Kumar; Manna, Himadri
2016-12-01
In supersymmetric models with minimal particle content and without large left-right squarks mixing, the conventional knowledge is that the Higgs Boson mass around 125 GeV leads to top squark masses O (10) TeV, far beyond the reach of colliders. Here, we pointed out that this conclusion is subject to several theoretical uncertainties. We find that electroweak symmetry breaking and evaluation of Higgs mass at a scale far away from the true electroweak symmetry breaking scale introduce a large uncertainty in Higgs mass calculation. We show that the electroweak symmetry breaking at the scale near the true vacuum expectation value of Higgs field can increase the Higgs Boson mass about 4-5 GeV and can lower the bounds on squarks and slepton masses to 1 TeV. Here we pointed out that the Higgs mass even with inclusion of radiative corrections can vary with electroweak symmetry breaking scale. We calculate it at two loop level and show that it varies substantially. We argue that Higgs mass like other coupling parameters can vary with energy scale and the Higgs potential with all orders loop corrections is scale invariant. This uncertainty to the Higgs mass calculation due to electroweak symmetry breaking around the supersymmetry breaking scale, normally taken as √{mt˜Lmt˜R }, to minimize the 1-loop radiative corrections can be removed if one considers all significant radiative contributions to make Higgs potential renormalization group evolution scale invariant and evaluates electroweak symmetry breaking at the scale near the electroweak symmetry breaking scale. A large parameter space becomes allowed when one considers electroweak symmetry breaking at its true scale not only for producing correct values of the Higgs masses, but also for providing successful breaking of this symmetry in more parameter spaces.
Patterns of Flavour Violation in the RSc Model, the LHT Model and Supersymmetric Flavour Models
Buras, Andrzej J
2009-01-01
We summarize the results on patterns of flavour violation in a Randall-Sundrum model with custodial protection (RSc) and compare them with those identified in the Littlest Higgs Model with T--parity (LHT) and in a number of SUSY Flavour Models. While K decays play in this presentation a prominent role, the inclusion of B physics and lepton flavour violation is crucial in the distinction between these three popular extensions of the Standard Model (SM) by means of flavour physics.
E Coniavitis; A Ferrari
2007-11-01
The minimal supersymmetric extension of the standard model (MSSM) predicts the existence of new charged and neutral Higgs bosons. The pair creation of these new particles at the multi-TeV + − compact linear collider (CLIC), followed by decays into standard model particles, were simulated along with the corresponding background. High-energy beam–beam effects such as ISR, beamstrahlung and hadronic background were included. We have investigated the possibility of using the ratio between the number of events found in various decay channels to determine the MSSM parameter tan and we have derived the corresponding statistical error from the uncertainties on the measured cross-sections and Higgs boson masses.
Probing Neutrino Oscillations in Supersymmetric Models at the Large Hadron Collider
De Campos, F; Hirsch, M; Magro, M B; Porod, W; Restrepo, D; Valle, J W F
2010-01-01
The lightest supersymmetric particle may decay with branching ratios that correlate with neutrino oscillation parameters. In this case the CERN Large Hadron Collider (LHC) has the potential to probe the atmospheric neutrino mixing angle with sensitivity competitive to its low-energy determination by underground experiments. Under realistic detection assumptions, we identify the necessary conditions for the experiments at CERN's LHC to probe the simplest scenario for neutrino masses induced by minimal supergravity with bilinear R parity violation.
Some Aspects of Dynamical Mass Generation
Sauli, V B
2004-01-01
The phenomena of dynamical mass generation (DMG) are discussed in the framework of gap equations. The examples are reviewed or studied in a few cases of the models- QCD,QED and SUSY Yukawa (Wess-Zumino) model. The models with simultaneous mass generation but not particle condensation or confinement are looking for. It is argued which kind of criteria such models must satisfy.
Decoupling of supersymmetric particles
Dobado, A; Peñaranda, S
1999-01-01
The possibility of a heavy supersymmetric spectrum at the Minimal Supersymmetric Standard Model is considered and the decoupling from the low energy electroweak scale is analyzed in detail. The formal proof of decoupling of supersymmetric particles from low energy physics is stated in terms of the effective action for the particles of the Standard Model that results by integrating out all the sparticles in the limit where their masses are larger than the electroweak scale. The computation of the effective action for the standard electroweak gauge bosons W^{+-}, Z and \\gamma is performed by integrating out all the squarks, sleptons, charginos and neutralinos to one-loop. The Higgs sector is not considered in this paper. The large sparticle masses limit is also analyzed in detail. Explicit analytical formulae for the two-point functions of the electroweak gauge bosons to be valid in that limit are presented. Finally, the decoupling of sparticles in the S, T and U parameters is studied analitically. A discussion...
Exact solution of the one-dimensional super-symmetric t-J model with unparallel boundary fields
Zhang, Xin; Yang, Wen-Li; Shi, Kangjie; Wang, Yupeng
2013-01-01
The exact solution of the one-dimensional super-symmetric t-J model under generic integrable boundary conditions is obtained via the Bethe ansatz methods. With the coordinate Bethe ansatz, the corresponding R-matrix and K-matrices are derived for the second eigenvalue problem associated with spin degrees of freedom. It is found that the second eigenvalue problem can be transformed to that of the transfer matrix of the inhomogeneous XXX spin chain, which allows us to obtain the spectrum of the Hamiltonian and the associated Bethe ansatz equations by the off-diagonal Bethe ansatz method.
A simple model of generating fermion mass hierarchy in N=1 supersymmetric 6D SO(10) GUT
Haba, N; Haba, Naoyuki; Shimizu, Yasuhiro
2003-01-01
We suggest simple models which produce the suitable fermion mass hierarchies and flavor mixing angles based on the 6 dimensional N=1 supersymmetric SO(10) grand unified theory compactified on a $T^2/(Z_2 \\times Z_2')$ orbifold. We introduce 6D and 5D matter fields, which contains the 1st and 2nd generation matter fields as the zero modes, respectively. The 3rd generation matter fields are located on a 4D brane. The Yukawa couplings for bulk fields are suppressed by volume factors from extra dimensions. The suitable fermion mass hierarchies and flavor mixings are generated by the volume suppression factors.
Yamanaka, Nodoka
2012-01-01
We evaluate the Barr-Zee type two-loop level contribution to the fermion electric and chromo-electric dipole moments with sfermion loop in R-parity violating supersymmetric models. It is found that the Barr-Zee type fermion dipole moment with sfermion loop acts destructively to the currently known fermion loop contribution, and that it has small effect when the mass of squarks or charged sleptons in the loop is larger than or comparable to that of the sneutrinos, but cannot be neglected if the sneutrinos are much heavier than loop sfermions.
González-Ruiz, A
1994-01-01
We consider integrable open-boundary conditions for the supersymmetric t-J model commuting with the number operator $n$ and $S^{z}$. We find four families, each one depending on two arbitrary parameters. The associated eigenvalue problem is solved by generalizing the Nested Algebraic Bethe Ansatz of the quantum group invariant case (which is obtained as a special limit). For the quantum group invariant case the Bethe ansatz states are shown to be highest weights of $spl_{q}(2,1)$. We also discuss the relation between Sklyanin's method of constructing open boundary conditions and the one for the quantum group invariant case based on Markov traces.
Instanton Corrected Non-Supersymmetric Attractors
Dominic, Pramod
2010-01-01
We discuss non-supersymmetric attractors with an instanton correction in Type IIA string theory compactified on a Calabi-Yau three-fold at large volume. For a stable non-supersymmetric black hole, the attractor point must minimize the effective black hole potential. We study the supersymmetric as well as non-supersymmetric attractors for the D0-D4 system with instanton corrections. We show that in simple models, like the STU model, the flat directions of the mass matrix can be lifted by a suitable choice of the instanton parameters.
Duality in supersymmetric Yang-Mills theory
Peskin, M.E.
1997-02-01
These lectures provide an introduction to the behavior of strongly-coupled supersymmetric gauge theories. After a discussion of the effective Lagrangian in nonsupersymmetric and supersymmetric field theories, the author analyzes the qualitative behavior of the simplest illustrative models. These include supersymmetric QCD for N{sub f} < N{sub c}, in which the superpotential is generated nonperturbatively, N = 2 SU(2) Yang-Mills theory (the Seiberg-Witten model), in which the nonperturbative behavior of the effect coupling is described geometrically, and supersymmetric QCD for N{sub f} large, in which the theory illustrates a non-Abelian generalization of electric-magnetic duality. 75 refs., 12 figs.
Lorentz violation in supersymmetric field theories.
Nibbelink, Stefan Groot; Pospelov, Maxim
2005-03-04
We construct supersymmetric Lorentz violating operators for matter and gauge fields. We show that in the supersymmetric standard model the lowest possible dimension for such operators is five, and therefore they are suppressed by at least one power of an ultraviolet energy scale, providing a possible explanation for the smallness of Lorentz violation and its stability against radiative corrections. Supersymmetric Lorentz noninvariant operators do not lead to modifications of dispersion relations at high energies thereby escaping constraints from astrophysical searches for Lorentz violation.
Hahn, T; Heinemeyer, S; Hollik, W; Rzehak, H; Weiglein, G
2014-04-11
For the interpretation of the signal discovered in the Higgs searches at the LHC it will be crucial in particular to discriminate between the minimal Higgs sector realized in the standard model (SM) and its most commonly studied extension, the minimal supersymmetric standard model (MSSM). The measured mass value, having already reached the level of a precision observable with an experimental accuracy of about 500 MeV, plays an important role in this context. In the MSSM the mass of the light CP-even Higgs boson, Mh, can directly be predicted from the other parameters of the model. The accuracy of this prediction should at least match the one of the experimental result. The relatively high mass value of about 126 GeV has led to many investigations where the scalar top quarks are in the multi-TeV range. We improve the prediction for Mh in the MSSM by combining the existing fixed-order result, comprising the full one-loop and leading and subleading two-loop corrections, with a resummation of the leading and subleading logarithmic contributions from the scalar top sector to all orders. In this way for the first time a high-precision prediction for the mass of the light CP-even Higgs boson in the MSSM is possible all the way up to the multi-TeV region of the relevant supersymmetric particles. The results are included in the code FEYNHIGGS.
Wolfgang Gregor Hollik
2016-01-01
Full Text Available Testing the stability of the electroweak vacuum in any extension of the Standard Model Higgs sector is of great importance to verify the consistency of the theory. Multi-scalar extensions as the Minimal Supersymmetric Standard Model generically lead to unstable configurations in certain regions of parameter space. An exact minimization of the scalar potential is rather an impossible analytic task. To give handy analytic constraints, a specific direction in field space has to be considered which is a simplification that tends to miss excluded regions, however good to quickly check parameter points. We describe a yet undescribed class of charge and color breaking minima as they appear in the Minimal Supersymmetric Standard Model, exemplarily for the case of non-vanishing bottom squark vacuum expectation values constraining the combination μYb in a non-trivial way. Contrary to famous A-parameter bounds, we relate the bottom Yukawa coupling with the supersymmetry breaking masses. Another bound can be found relating soft breaking masses and μ only. The exclusions follow from the tree-level minimization and can change dramatically using the one-loop potential. Estimates of the lifetime of unstable configurations show that they are either extremely short- or long-lived.
Non-Minimal Higgs Inflation and non-Thermal Leptogenesis in A Supersymmetric Pati-Salam Model
Pallis, C
2011-01-01
We consider a supersymmetric (SUSY) Grand Unified Theory (GUT) based on the gauge group G_PS=SU(4)_C x SU(2)_L x SU(2)_R, which incorporates non-minimal chaotic inflation, driven by a quartic potential associated with the Higgs fields involved in the spontaneous breaking of G_PS. The inflationary model relies on renormalizable superpotetial terms and does not lead to overproduction of magnetic monopoles. It is largely independent of the one-loop radiative corrections and can become consistent with the current observational data on the inflationary observables, with the symmetry breaking scale of G_PS assuming its SUSY value. Within our model, the strong CP and the mu problems of the minimal supersymmetric standard model can be resolved via a Peccei-Quinn symmetry. Moreover baryogenesis occurs via non-thermal leptogenesis realized by the out-of-equilibrium decay of the right-handed neutrinos, which are produced by the inflaton's decay. We consider two versions of such a scenario, assuming that the inflaton dec...
Carvalho, L. Faria; Toppan, F., E-mail: leofc@cbpf.b, E-mail: toppan@cbpf.b [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Kuznetsova, Z., E-mail: zhanna.kuznetsova@ufabc.edu.b [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil)
2009-07-01
We discuss four off-shell N = 4 D = 1 supersymmetry transformations, their associated one-dimensional -models and their mutual relations. They are given by I - the (4, 4){sub lin} linear 'root' supermultiplet (supersymmetric extension of R{sup 4}), II - the (3, 4, 1){sub lin} linear supermultiplet (supersymmetric extension of R3), III - the (3, 4, 1){sub nl} non-linear supermultiplet living on S{sup 3} and IV - the (2, 4, 2){sub nl} non-linear supermultiplet living on S{sup 2}. The I {yields} II map is the supersymmetric extension of the R4 {yields} R3 bilinear map, while the II {yields} IV map is the supersymmetric extension of the S{sup 3} {yields} S{sup 2} first Hopf fibration. The restrictions on the S{sup 3}, S{sup 2} spheres are expressed in terms of the stereo graphic projections. The non-linear supermultiplets, whose super transformations are local differential polynomials, are not equivalent to the linear supermultiplets with the same field content. The -models are determined in terms of an unconstrained pre potential of the target coordinates. The Uniformization Problem requires solving an inverse problem for the pre potential. The basic features of the supersymmetric extension of the second and third Hopf maps are briefly sketched. Finally, the Schur's lemma (i.e. the real, complex or quaternionic property) is extended to all minimal linear supermultiplets up to N {<=} 8. (author)
Enhancement of proton decay rates in supersymmetric SU(5) grand unified models
Hisano, Junji; Kobayashi, Daiki; Nagata, Natsumi
2012-10-01
In the supersymmetric grand unified theories (SUSY GUTs), gauge bosons associated with the unified gauge group induce proton decay. We investigate the proton decay rate via the gauge bosons in the SUSY GUTs under the two situations; one is with extra vector-like multiplets, and the other is with heavy sfermions. It is found that the proton lifetime is significantly reduced in the former case, while in the latter case it is slightly prolonged. Determination of the particle contents and their mass spectrum below the GUT scale is important to predict the proton lifetime. The proton decay searches have started to access to the 1016GeV scale.
Enhancement of Proton Decay Rates in Supersymmetric SU(5) Grand Unified Models
Hisano, Junji; Nagata, Natsumi
2012-01-01
In the supersymmetric grand unified theories (SUSY GUTs), gauge bosons associated with the unified gauge group induce proton decay. We investigate the proton decay rate via the gauge bosons in the SUSY GUTs under the two situations; one is with extra vector-like multiplets, and the other is with heavy sfermions. It is found that the proton lifetime is significantly reduced in the former case, while in the latter case it is slightly prolonged. Determination of the particle contents and their mass spectrum below the GUT scale is important to predict the proton lifetime. The proton decay searches have started to access to the 10^16 GeV scale.
Fusion rings and fusion ideals
Andersen, Troels Bak
by the so-called fusion ideals. The fusion rings of Wess-Zumino-Witten models have been widely studied and are well understood in terms of precise combinatorial descriptions and explicit generating sets of the fusion ideals. They also appear in another, more general, setting via tilting modules for quantum...
Complex sine-Gordon Equation in Coherent Optical Pulse Propagation
Park, Q H
1999-01-01
It is shown that the McCall-Hahn theory of self-induced transparency in coherent optical pulse propagation can be identified with the complex sine-Gordon theory in the sharp line limit. We reformulate the theory in terms of the deformed gauged Wess-Zumino-Witten sigma model and address various new aspects of self-induced transparency.
Quasiparticle operators with non-abelian braiding statistics
Cabra, D C; Rossini, G L; Cabra, Daniel C.; Moreno, Enrique F.; Rossini, Gerardo L.
1998-01-01
We study the gauge invariant fermions in the fermion coset representation of $SU(N)_k$ Wess-Zumino-Witten models which create, by construction, the physical excitations (quasiparticles) of the theory. We show that they provide an explicit holomorphic factorization of $SU(N)_k$ WZW primaries and satisfy non-abelian braiding relations.
Constraints on the rare tau decays from {mu} {yields} e{gamma} in the supersymmetric see-saw model
Ibarra, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Simonetto, C. [Technische Univ., Muenchen (Germany). Physik-Department
2008-02-15
It is now a firmly established fact that all family lepton numbers are violated in Nature. In this paper we discuss the implications of this observation for future searches for rare tau decays in the supersymmetric see-saw model. Using the two loop renormalization group evolution of the soft terms and the Yukawa couplings we show that there exists a lower bound on the rate of the rare process {mu}{yields}e{gamma} of the form BR({mu}{yields}e{gamma})>or similar C x BR({tau}{yields}{mu}{gamma})BR({tau}{yields}e{gamma}), where C is a constant that depends on supersymmetric parameters. Our only assumption is the absence of cancellations among the high-energy see-saw parameters. We also discuss the implications of this bound for future searches for rare tau decays. In particular, for large regions of the mSUGRA parameter space, we show that present B-factories could discover either {tau}{yields}{mu}{gamma} or {tau}{yields}e{gamma}, but not both. (orig.)
Harnik, R
2004-01-01
Supersymmetric models have traditionally been assumed to be perturbative up to high scales due to the requirement of calculable unification. In this note I review the recently proposed `Fat Higgs' model which relaxes the requirement of perturbativity. In this framework, an NMSSM-like trilinear coupling becomes strong at some intermediate scale. The NMSSM Higgses are meson composites of an asymptotically-free gauge theory. This allows us to raise the mass of the Higgs, thus alleviating the MSSM of its fine tuning problem. Despite the strong coupling at an intermediate scale, the UV completion allows us to maintain gauge coupling unification.
Supersymmetric coupling of a self-dual string to a (2, 0) tensor multiplet background
Arvidsson, Paer; Flink, Erik; Henningson, Maaans [Department of Theoretical Physics, Chalmers University of Technology and Gaeteborg University, Gaeteborg (Sweden)]. E-mail addresses: par@fy.chalmers.se; erik.flink@fy.chalmers.se; mans@fy.chalmers.se
2003-11-01
We construct an interaction between a (2, 0) tensor multiplet in six dimensions and a self-dual string. The interaction is a sum of a Nambu-Goto term, with the tension of the string given by the modulus of the scalar fields of the tensor multiplet, and a non- local Wess-Zumino term, that encodes the electromagnetic coupling of the string to the two-form gauge field of the tensor multiplet. The interaction is invariant under global (2, 0) supersymmetry, modulo the equations of motion of a free tensor multiplet. It is also invariant under a local fermionic {kappa}-symmetry, as required by the BPS-property of the string. (author)
Two-photon decay of the Higgs bosons in a supersymmetric model with a C P -violating potential
Oshimo, Noriyuki
2016-05-01
In the supersymmetric standard model which is not minimal, the Higgs potential does not conserve C P symmetry generally. Assuming that there exists an SU(2)-triplet Higgs field, we discuss resultant C P -violating effects on the Higgs bosons. The experimentally observed Higgs boson, which should be C P even in the standard model, could decay into two photons of C P -odd polarization state non-negligibly. For the second lightest Higgs boson, in a sizable region of parameter space, the dominant decay modes are different from those expected by the standard model. The two-photon decay could yield both even and odd C P final states at a ratio of the order of unity.
CP Phases of Neutrino Mixing in a Supersymmetric B-L Gauge Model with T_7 Lepton Flavor Symmetry
Ishimori, Hajime; Ma, Ernest
2012-01-01
In a recently proposed renormalizable model of neutrino mixing using the non-Abelian discrete symmetry T_7 in the context of a supersymmetric extension of the Standard Model with gauged U(1)_{B-L}, a correlation was obtained between \\theta_{13} and \\theta_{23} in the case where all parameters are real. Here we consider all parameters to be complex, thus allowing for one Dirac CP phase \\delta_{CP} and two Majorana CP phases \\alpha_{1,2}. We find a slight modification to this correlation as a function of \\delta_{CP}. For a given set of input values of \\Delta m^2_{21}, \\Delta m^2_{32}, \\theta_{12}, and \\theta_{13}, we obtain \\sin^2 2 \\theta_{23} and m_{ee} (the effective Majorana neutrino mass in neutrinoless double beta decay) as functions of \\tan \\delta_{CP}. We find that the structure of this model always yields small |\\tan \\delta_{CP}|.
Asano, E A; Gomes, M; Petrov, A Yu; Rodrigues, A G; Silva, A J
2004-01-01
We consider the coupling of fermions to the three-dimensional noncommutative $CP^{N-1}$ model. In the case of minimal coupling, although the infrared behavior of the gauge sector is improved, there are dangerous (quadratic) infrared divergences in the corrections to the two point vertex function of the scalar field. However, using superfield techniques we prove that the supersymmetric version of this model with ``antisymmetrized'' coupling of the Lagrange multiplier field is renormalizable up to the first order in $\\frac{1}{N}$. The auxiliary spinor gauge field acquires a nontrivial (nonlocal) dynamics with a generation of Maxwell and Chern-Simons noncommutative terms in the effective action. Up to the 1/N order all divergences are only logarithimic so that the model is free from nonintegrable infrared singularities.
Kneur, J.L
2006-06-15
This document is divided into 2 parts. The first part describes a particular re-summation technique of perturbative series that can give a non-perturbative results in some cases. We detail some applications in field theory and in condensed matter like the calculation of the effective temperature of Bose-Einstein condensates. The second part deals with the minimal supersymmetric standard model. We present an accurate calculation of the mass spectrum of supersymmetric particles, a calculation of the relic density of supersymmetric black matter, and the constraints that we can infer from models.
Supersymmetric R4-actions in ten dimensions
Roo, M. de; Suelmann, H.; Wiedemann, A.
1992-01-01
We construct supersymmetric R+R4-actions in ten dimensions. Two invariants, of which the bosonic parts are known from string amplitude and sigma model calculations, are obtained. One of these invariants can be generalized to an R+F2+F4-invariant for supersymmetric Yang-Mills theory coupled to superg
Higaki, Tetsutaro; Nishida, Michinobu; Takeda, Naoyuki
2017-08-01
We study a supersymmetric model in which the Higgs mass, the muon anomalous magnetic moment, and the dark matter are simultaneously explained with extra vector-like generation multiplets. For the explanations, non-trivial flavor structures and a singlet field are required. In this paper, we study the flavor texture by using the Froggatt-Nielsen mechanism, and then find realistic flavor structures that reproduce the Cabbibo-Kobayashi-Maskawa matrix and fermion masses at low energy. Furthermore, we find that the fermion component of the singlet field becomes a good candidate for dark matter. In our model, flavor physics and dark matter are explained with moderate-size couplings through renormalization group flows, and the presence of dark matter supports the existence of just 3 generations in low-energy scales. We analyze the parameter region where the current thermal relic abundance of dark matter, the Higgs boson mass, and the muon g{-}2 can be explained simultaneously.
Non-standard charged Higgs decay at the LHC in Next-to-Minimal Supersymmetric Standard Model
Bandyopadhyay, Priyotosh [Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento and INFN-Lecce,Via Arnesano, 73100 Lecce (Italy); Huitu, Katri [Department of Physics, and Helsinki Institute of Physics,P.O.B 64 (Gustaf Hällströmin katu 2), FI-00014 University of Helsinki (Finland); Niyogi, Saurabh [The Institute of Mathematical Sciences,CIT Campus, Chennai (India)
2016-07-04
We consider next-to-minimal supersymmetric standard model (NMSSM) which has a gauge singlet superfield. In the scale invariant superpotential we do not have the mass terms and the whole Lagrangian has an additional Z{sub 3} symmetry. This model can have light scalar and/or pseudoscalar allowed by the recent data from LHC and the old data from LEP. We investigate the situation where a relatively light charged Higgs can decay to such a singlet-like pseudoscalar and a W{sup ±} boson giving rise to a final state containing τ and/or b-jets and lepton(s). Such decays evade the recent bounds on charged Higgs from the LHC, and according to our PYTHIA-FastJet based simulation can be probed with 10 fb{sup −1} at the LHC center of mass energy of 13 and 14 TeV.
Generalized Supersymmetric Perturbation Theory
B. G(o)n(ǖ)l
2004-01-01
@@ Using the basic ingredient of supersymmetry, a simple alternative approach is developed to perturbation theory in one-dimensional non-relativistic quantum mechanics. The formulae for the energy shifts and wavefunctions do not involve tedious calculations which appear in the available perturbation theories. The model applicable in the same form to both the ground state and excited bound states, unlike the recently introduced supersymmetric perturbation technique which, together with other approaches based on logarithmic perturbation theory, are involved within the more general framework of the present formalism.
Supersymmetric Electroweak Baryogenesis
Rius, N; Rius, Nuria; Sanz, Veronica
2000-01-01
We calculate the baryon asymmetry generated at the electroweak phase transition in the minimal supersymmetric standard model, using a new method to compute the CP-violating asymmetry in the Higgsino flux reflected into the unbroken phase. The method is based on a Higgs insertion expansion. We find that the CP asymmetry at leading order is proportional to the change in $\\tan next-to-leading order this suppression factor disappears. These results explain previous discrepancies among different calculations, and may enhance the final baryon asymmetry generated during the electroweak phase transition.
Supersymmetric vacua in random supergravity
Bachlechner, Thomas C.; Marsh, David; McAllister, Liam; Wrase, Timm
2013-01-01
We determine the spectrum of scalar masses in a supersymmetric vacuum of a general mathcal{N}=1 supergravity theory, with the Kähler potential and superpotential taken to be random functions of N complex scalar fields. We derive a random matrix model for the Hessian matrix and compute the eigenvalue spectrum. Tachyons consistent with the Breitenlohner-Freedman bound are generically present, and although these tachyons cannot destabilize the supersymmetric vacuum, they do influence the likelihood of the existence of an `uplift' to a metastable vacuum with positive cosmological constant. We show that the probability that a supersymmetric AdS vacuum has no tachyons is formally equivalent to the probability of a large fluctuation of the smallest eigenvalue of a certain real Wishart matrix. For normally-distributed matrix entries and any N, this probability is given exactly by P=exp left( {{{{-2{N^2}{{{left| W right|}}^2}}} left/ {{m_{susy}^2}} right.}} right) , with W denoting the superpotential and m susy the supersymmetric mass scale; for more general distributions of the entries, our result is accurate when N ≫ 1. We conclude that for left| W right|gtrsim {{{{m_{susy}}}} left/ {N} right.} , tachyonic instabilities are ubiquitous in configurations obtained by uplifting supersymmetric vacua.
Hung, Ling-Yan; Wang, Yixu
2016-01-01
We studied the leading area term of the entanglement entropy of $\\mathcal{N}=1$ supersymmetric $O(N)$ vector model in $2+1$ dimensions close to the line of second order phase transition in the large $N$ limit. We found that the area term is independent of the varying interaction coupling along the critical line, unlike what is expected in a perturbative theory. Along the way, we studied non-commuting limits $n-1\\to 0$ verses UV cutoff $r\\to 0$ when evaluating the gap equation and found a match only when appropriate counter term is introduced and whose coupling is chosen to take its fixed point value. As a bonus, we also studied Fermionic Green's functions in the conical background. We made the observation of a map between the problem and the relativistic hydrogen atom.
Consistent supersymmetric decoupling in cosmology
Sousa Sánchez, Kepa
2012-01-01
The present work discusses several problems related to the stability of ground states with broken supersymmetry in supergravity, and to the existence and stability of cosmic strings in various supersymmetric models. In particular we study the necessary conditions to truncate consistently a sector o
Weakly-Interacting Massive Particles in Non-supersymmetric SO(10) Grand Unified Models
Nagata, Natsumi; Zheng, Jiaming
2015-01-01
Non-supersymmetric SO(10) grand unified theories provide a framework in which the stability of dark matter is explained while gauge coupling unification is realized. In this work, we systematically study this possibility by classifying weakly interacting DM candidates in terms of their quantum numbers of $\\text{SU}(2)_L \\otimes \\text{U}(1)_Y$, $B-L$, and $\\text{SU}(2)_R$. We consider both scalar and fermion candidates. We show that the requirement of a sufficiently high unification scale to ensure a proton lifetime compatible with experimental constraints plays a strong role in selecting viable candidates. Among the scalar candidates originating from either a 16 or 144 of SO(10), only SU(2)$_L$ singlets with zero hypercharge or doublets with $Y=1/2$ satisfy all constraints for $\\text{SU}(4)_C \\otimes \\text{SU}(2)_L \\otimes \\text{SU}(2)_R$ and $\\text{SU}(3)_C \\otimes \\text{SU}(2)_L \\otimes \\text{SU}(2)_R \\otimes \\text{U}(1)_{B-L}$ intermediate scale gauge groups. Among fermion triplets with zero hypercharge, o...
You, Yi-Zhuang; Bi, Zhen; Mao, Dan; Xu, Cenke
2016-03-01
We propose a series of simple two-dimensional (2D) lattice interacting fermion models that we demonstrate at low energy describe bosonic symmetry-protected topological (SPT) states and quantum phase transitions between them. This is because due to interaction, the fermions are gapped both at the boundary of the SPT states and at the bulk quantum phase transition, thus these models at low energy can be described completely by bosonic degrees of freedom. We show that the bulk of these models is described by a Sp (N ) principal chiral model with a topological Θ term, whose boundary is described by a Sp (N ) principal chiral model with a Wess-Zumino-Witten term at level 1. The quantum phase transition between SPT states in the bulk is tuned by a particular interaction term, which corresponds to tuning Θ in the field theory, and the phase transition occurs at Θ =π . The simplest version of these models with N =1 is equivalent to the familiar O(4) nonlinear sigma model (NLSM) with a topological term, whose boundary is a (1 +1 )D conformal field theory with central charge c =1 . After breaking the O(4) symmetry to its subgroups, this model can be viewed as bosonic SPT states with U(1), or Z2 symmetries, etc. All of these fermion models, including the bulk quantum phase transitions, can be simulated with the determinant quantum Monte Carlo method without the sign problem. Recent numerical results strongly suggest that the quantum disordered phase of the O(4) NLSM with precisely Θ =π is a stable (2 +1 )D conformal field theory with gapless bosonic modes.
Supersymmetric Displaced Number States
Fredy R. Zypman
2015-06-01
Full Text Available We introduce, generate and study a family of supersymmetric displaced number states (SDNS that can be considered generalized coherent states of the supersymmetric harmonic oscillator. The family is created from the seminal supersymmetric boson-fermion entangling annihilation operator introduced by Aragone and Zypman and later expanded by Kornbluth and Zypman. Using the momentum representation, the states are obtained analytically in compact form as displaced supersymmetric number states. We study their position-momentum uncertainties, and their bunchiness by classifying them according to their Mandel Q-parameter in phase space. We were also able to find closed form analytical representations in the space and number basis.
Supersymmetric Open Wilson Lines
Baker, Edward B
2011-01-01
In this paper we study Open Wilson Lines (OWL's) in the context of two Supersymmetric Yang Mills theories. First we consider four dimensional N=2 Supersymmetric Yang Mills Theory with hypermultiplets transforming in the fundamental representation of the gauge group, and find supersymmetric OWL's only in the superconformal versions of these theories. We then consider four dimensional N=4 SYM coupled to a three dimensional defect hypermultiplet. Here there is a semi-circular supersymmetric OWL, which is related to the ray by a conformal transformation. We perform a perturbative calculation of the operators in both theories, and discuss using localization to compute them non-perturbatively.
Supersymmetrizing Massive Gravity
Malaeb, Ola
2013-01-01
When four scalar fields with global Lorentz symmetry are coupled to gravity and take a vacuum expectation value breaking diffeomorphism invariance spontaneously, the graviton becomes massive. This model is supersymmetrized by considering four N=1 chiral superfields with global Lorentz symmetry. When the scalar components of the chiral multiplets z^A acquire a vacuum expectation value, both diffeomorphism invariance and local supersymmetry are broken spontaneously. The global Lorentz index A becomes identified with the space-time Lorentz index making the scalar fields z^A vectors and the chiral spinors \\psi^A spin-3/2 Rarita-Schwinger fields. The global supersymmetry is promoted to a local one using the rules of tensor calculus of coupling the N=1 supergravity Lagrangian to the four chiral multiplets. We show that the spectrum of the model in the broken phase consists of a massive spin-2 field, two massive spin-3/2 fields with different mass and a massive vector.
Pahel, D J
2005-01-01
In the standard electroweak model, the sole source of CP violation is a CP violating phase of the CKM quark mixing matrix. The minimal supersymmetric extension of the standard model offers a large number of possible new sources of CP violation; these include both flavor dependent and flavor independent sources. These CP violating effects are studied in gauge boson production and decay processes with intermediate W and Z boson exchange. The prospects of measuring these effects in the International Linear Collider are explored.
Supersymmetric Vacua in Random Supergravity
Bachlechner, Thomas C; McAllister, Liam; Wrase, Timm
2012-01-01
We determine the spectrum of scalar masses in a supersymmetric vacuum of a general N=1 supergravity theory, with the Kahler potential and superpotential taken to be random functions of N complex scalar fields. We derive a random matrix model for the Hessian matrix and compute the eigenvalue spectrum. Tachyons consistent with the Breitenlohner-Freedman bound are generically present, and although these tachyons cannot destabilize the supersymmetric vacuum, they do influence the likelihood of the existence of an `uplift' to a metastable vacuum with positive cosmological constant. We show that the probability that a supersymmetric AdS vacuum has no tachyons is formally equivalent to the probability of a large fluctuation of the smallest eigenvalue of a certain real Wishart matrix. For normally-distributed matrix entries and any N, this probability is given exactly by P = exp(-2N^2|W|^2/m_{susy}^2), with W denoting the superpotential and m_{susy} the supersymmetric mass scale; for more general distributions of the...
Mono-jet, -photon and -Z Signals of a Supersymmetric (B-L) model at the Large Hadron Collider
Abdallah, W; Khalil, S; Moretti, S
2015-01-01
Search for invisible final states produced at the Large Hadron Collider (LHC) by new physics scenarios are normally carried out resorting to a variety of probes emerging from the initial state, in the form of single-jet, -photon and -$Z$ boson signatures. These are particularly effective for models of Supersymmetry (SUSY) in presence of $R$-parity conservation, owing to the presence in their spectra of a stable neutralino as dark matter candidate. We assume here as theoretical framework Supersymmetric ($B-L$) extension of the Standard Model (BLSSM), wherein a mediator for invisible decays can be $Z'$ boson. The peculiarity of the signal is thus that the final state objects carry a very large (transverse) missing energy, since the $Z'$ is naturally massive and constrained by direct searches and electro-weak precision tests to be at least in TeV scale region. Under these circumstances the efficiency in accessing the invisible final state and rejecting the standard model background is very high. This somehow com...
Supersymmetric non conservative systems
Martínez-Pérez, N E
2015-01-01
We give the generalization of a recent variational formulation for nonconservative classical mechanics, for fermionic and sypersymmetric systems. Both cases require slightly modified boundary conditions. The supersymmetric version is given in the superfield formalism. The corresponding Noether theorem is formulated. As expected, like the energy, the supersymmetric charges are not conserved. Examples are discussed.
Lapa, Matthew F.; Hughes, Taylor L.
2017-08-01
We canonically quantize O (D +2 ) nonlinear sigma models (NLSMs) with a theta term on arbitrary smooth, closed, connected, oriented D -dimensional spatial manifolds M , with the goal of proving the suitability of these models for describing symmetry-protected topological (SPT) phases of bosons in D spatial dimensions. We show that in the disordered phase of the NLSM, and when the coefficient θ of the theta term is an integer multiple of 2 π , the theory on M has a unique ground state and a finite energy gap to all excitations. We also construct the ground state wave functional of the NLSM in this parameter regime, and we show that it is independent of the metric on M and given by the exponential of a Wess-Zumino term for the NLSM field, in agreement with previous results on flat space. Our results show that the NLSM in the disordered phase and at θ =2 π k , k ∈Z , has a symmetry-preserving ground state but no topological order (i.e., no topology-dependent ground state degeneracy), making it an ideal model for describing SPT phases of bosons. Thus, our work places previous results on SPT phases derived using NLSMs on solid theoretical ground. To canonically quantize the NLSM on M , we use Dirac's method for the quantization of systems with second class constraints, suitably modified to account for the curvature of space. In a series of four Appendixes, we provide the technical background needed to follow the discussion in the main sections of the paper.
Kiourkos, S
1999-01-01
One of the potentially accessible decay modes of the Higgs boson in the mass region $100 < m_H < 180$ GeV is the $H^0 \\rightarrow Z^0 \\gamma$ channel. The work presented in this note examines the Standard Model and Minimal Supersymmetric Standard Model predictions for the observability of this channel using particle level simulation as well as the ATLAS fast simulation (ATLFAST). It compares present estimates for the signal observability with previously reported ones in \\cite{unal} specifying the changes arising from the assumed energy of the colliding protons and the improvements in the treatment of theoretical predictions. With the present estimates, the expected significance for the SM Higgs does not exceed, in terms of $\\frac{S}{\\sqrt{B}}$, 1.5 $\\sigma$ (including $Z^0 \\rightarrow e^+ e^-$ and $Z^0 \\rightarrow {\\mu}^+ {\\mu}^-$) for an integrated luminosity of $10^5$ pb$^{-1}$ therefore not favouring this channel for SM Higgs searches. Comparable discovery potential is expected at most for the MSSM $...
Supersymmetric Higgs Bosons and Beyond
Carena, Marcela; /Fermilab /Chicago U., EFI; Kong, Kyoungchul; /Fermilab /SLAC; Ponton, Eduardo; /Columbia U.; Zurita, Jose; /Fermilab /Buenos Aires U.
2010-08-26
We consider supersymmetric models that include particles beyond the Minimal Supersymmetric Standard Model (MSSM) with masses in the TeV range, and that couple significantly to the MSSM Higgs sector. We perform a model-independent analysis of the spectrum and couplings of the MSSM Higgs fields, based on an effective theory of the MSSM degrees of freedom. The tree-level mass of the lightest CP-even state can easily be above the LEP bound of 114 GeV, thus allowing for a relatively light spectrum of superpartners, restricted only by direct searches. The Higgs spectrum and couplings can be significantly modified compared to the MSSM ones, often allowing for interesting new decay modes. We also observe that the gluon fusion production cross section of the SM-like Higgs can be enhanced with respect to both the Standard Model and the MSSM.
Khan, Saki
2016-06-01
We present a minimal renormalizable non-supersymmetric S O(10) grand unified model with a symmetry breaking sector consisting of Higgs fields in the 54H + 126H + 10H representations. This model admits a single intermediate scale associated with Pati-Salam symmetry along with a discrete parity. Spontaneous symmetry breaking, the unification of gauge couplings and proton lifetime estimates are studied in detail in this framework. Including threshold corrections self-consistently, obtained from a full analysis of the Higgs potential, we show that the model is compatible with the current experimental bound on proton lifetime. The model generally predicts an upper bound of few times 1035 yrs for proton lifetime, which is not too far from the present Super-Kamiokande limit of τp ≳ 1.29 × 1034 yrs. With the help of a Pecci-Quinn symmetry and the resulting axion, the model provides a suitable dark matter candidate while also solving the strong CP problem. The intermediate scale, MI ≈ (1013 - 1014) GeV which is also the B - L scale, is of the right order for the right-handed neutrino mass which enables a successful description of light neutrino masses and oscillations. The Yukawa sector of the model consists of only two matrices in family space and leads to a predictive scenario for quark and lepton masses and mixings. The branching ratios for proton decay are calculable with the leading modes being p → e+π0 and p →v ¯π+ . Even though the model predicts no new physics within the reach of LHC, the next generation proton decay detectors and axion search experiments have the capability to pass verdict on this minimal scenario.
Bubbles of Nothing and Supersymmetric Compactifications
Blanco-Pillado, Jose J; Sousa, Kepa; Urrestilla, Jon
2016-01-01
We investigate the non-perturbative stability of supersymmetric compactifications with respect to decay via a bubble of nothing. We show examples where this kind of instability is not prohibited by the spin structure, i.e., periodicity of fermions about the extra dimension. However, such "topologically unobstructed" cases do exhibit an extra-dimensional analog of the well-known Coleman-De Luccia suppression mechanism, which prohibits the decay of supersymmetric vacua. We demonstrate this explicitly in a four dimensional Abelian-Higgs toy model coupled to supergravity. The compactification of this model to $M_3 \\times S_1$ presents the possibility of vacua with different windings for the scalar field. Away from the supersymmetric limit, these states decay by the formation of a bubble of nothing, dressed with an Abelian-Higgs vortex. We show how, as one approaches the supersymmetric limit, the circumference of the topologically unobstructed bubble becomes infinite, thereby preventing the realization of this dec...
On the uniqueness of supersymmetric attractors
Taniya Mandal
2015-10-01
Full Text Available In this paper we discuss the uniqueness of supersymmetric attractors in four-dimensional N=2 supergravity theories coupled to n vector multiplets. We prove that for a given charge configuration the supersymmetry preserving axion free attractors are unique. We generalise the analysis to axionic attractors and state the conditions for uniqueness explicitly. We consider the example of a two-parameter model and find all solutions to the supersymmetric attractor equations and discuss their uniqueness.
Bosonization of supersymmetric KdV equation
Gao Xiaonan [Department of Physics, Shanghai Jiao Tong University, Shanghai, 200240 (China); Lou, S.Y., E-mail: sylou@sjtu.edu.cn [Department of Physics, Shanghai Jiao Tong University, Shanghai, 200240 (China); Faculty of Science, Ningbo University, Ningbo, 315211 (China); School of Mathematics, Fudan University, Shanghai, 200433 (China)
2012-01-16
Bosonization approach to the classical supersymmetric systems is presented. By introducing the multi-fermionic parameters in the expansions of the superfields, the N=1 supersymmetric KdV (sKdV) system is transformed to a system of coupled bosonic equations. The method can be applied to any fermionic systems. By solving the coupled bosonic equations, some novel types of exact solutions can be explicitly obtained. Especially, the richness of the localized excitations of the supersymmetric integrable system is discovered. The rich multi-soliton solutions obtained here have not yet been obtained by using other methods. However, the traditional known multi-soliton solutions can also not be obtained by the bosonization approach of this Letter. Some open problems on the bosonization of the supersymmetric integrable models are proposed in the both classical and quantum levels.
Supersymmetric Color Superconductivity
Harnik, R; Murayama, H; Harnik, Roni; Larson, Daniel T.; Murayama, Hitoshi
2004-01-01
Recent interest in novel phases in high density QCD motivates the study of high density supersymmetric QCD (SQCD), where powerful exact results for supersymmetric gauge theories can be brought to bear in the strongly coupled regime. We begin by describing how a chemical potential can be incorporated into a supersymmetric theory as a spurion vector superfield. We then study supersymmetric SU(N_c) gauge theories with N_f flavors of quarks in the presence of a baryon chemical potential mu, and describe the global symmetry breaking patterns at low energy. Our analysis requires mu mu_c. We also give a qualitative description of the phases in the `conformal window', 3/2 N_c < N_f < 3N_c, at finite density.
Bandyopadhyay, Priyotosh [Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento and INFN-Lecce,Via Arnesano, 73100 Lecce (Italy); Corianò, Claudio [Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento and INFN-Lecce,Via Arnesano, 73100 Lecce (Italy); STAG Research Centre and Mathematical Sciences, University of Southampton,Southampton SO17 1BJ (United Kingdom); Costantini, Antonio [Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento and INFN-Lecce,Via Arnesano, 73100 Lecce (Italy)
2015-12-18
We investigate the scalar sector in an extension of the Minimal Supersymmetric Standard Model (MSSM) containing a SU(2) Higgs triplet of zero hypercharge and a gauge singlet beside the SU(2) scalar doublets. In particular, we focus on a scenario of this model which allows a light pseudoscalar and/or a scalar below 100 GeV, consistent with the most recent data from the LHC and the earlier data from the LEP experiments. We analyze the exotic decay of the discovered Higgs (h{sub 125}) into two light (hidden) Higgs bosons present in the extension. The latter are allowed by the uncertainties in the Higgs decay h{sub 125}→WW{sup ∗}, h{sub 125}→ZZ{sup ∗} and h{sub 125}→γγ. The study of the parameter space for such additional scalars/pseudoscalars decay of the Higgs is performed in the gluon fusion channel. The extra hidden Higgs bosons of the enlarged scalar sector, if they exist, will then decay into lighter fermion paris, i.e., bb̄, ττ̄ and μμ̄ via the mixing with the doublets. A detailed simulation using PYTHIA of the 2b+2τ, ≥3τ, 2b+2μ and 2τ+2μ final states is presented. From our analysis we conclude that, depending on the selected benchmark points, such decay modes can be explored with an integrated luminosity of 25 fb{sup −1} at the LHC at a center of mass energy of 13 TeV.
Supersymmetric color superconductivity
Harnik, Roni; Larson, Daniel T.; Murayama, Hitoshi
2003-09-18
Recent interest in novel phases in high density QCD motivates the study of high density supersymmetric QCD (SQCD), where powerful exact results for supersymmetric gauge theories can be brought to bear in the strongly coupled regime. We begin by describing how a chemical potential can be incorporated into a supersymmetric theory as a spurion vector superfield. We then study supersymmetric SU(N{sub c}) gauge theories with N{sub f} flavors of quarks in the presence of a baryon chemical potential {mu}, and describe the global symmetry breaking patterns at low energy. Our analysis requires {mu} < {Lambda} and is thus complementary to the variational approach that has been successful for {mu} >> {Lambda}. We find that for N{sub F} < N{sub c} a modified U(1){sub B} symmetry is preserved, analogous to the non-supersymmetric 2SC phase, whereas for N{sub f} = N{sub c} there is a critical chemical potential above which the U(1){sub B} is broken, as it is in the non-supersymmetric CFL phase. We further analyze the cases with N{sub c} + 1 {le} N{sub f} < 3/2 N{sub c} and find that baryon number is broken dynamically for {mu} > {mu}{sub c}. We also give a qualitative description of the phases in the ''conformal window'', 3/2 N{sub c} < N{sub f} < 3N{sub c}, at finite density.
Belich, H; Helayël-Neto, J A; Leal, F J L; Spalenza, W
2010-01-01
In this work, we present two possible venues to accomodate the $K_{F}$-type Lorentz-symmetry violating Electrodynamics in an $N=1$-supersymmetric framework. A chiral and a vector superfield are chosen to describe the background that signals Lorentz-symmetry breaking. In each case, the $\\ K_{\\mu \
Geometrical Lattice models for N=2 supersymmetric theories in two dimensions
Saleur, H
1992-01-01
We introduce in this paper two dimensional lattice models whose continuum limit belongs to the $N=2$ series. The first kind of model is integrable and obtained through a geometrical reformulation, generalizing results known in the $k=1$ case, of the $\\Gamma_{k}$ vertex models (based on the quantum algebra $U_{q}sl(2)$ and representation of spin $j=k/2$). We demonstrate in particular that at the $N=2$ point, the free energy of the $\\Gamma_{k}$ vertex model can be obtained exactly by counting arguments, without any Bethe ansatz computation, and we exhibit lattice operators that reproduce the chiral ring. The second class of models is more adequately described in the language of twisted $N=2$ supersymmetry, and consists of an infinite series of multicritical polymer points, which should lead to experimental realizations. It turns out that the exponents $\
Fun with supersymmetric quantum mechanics
Freedman, B.; Cooper, F.
1984-04-01
One reason for studying supersymmetric quantum mechanics is that there are a class of superpotentials W(x) which behave at large x as x/sup ..cap alpha../ for which we know from general arguments whether SUSY is broken or unbroken. Thus one can use these superpotentials to test various ideas about how to see if supersymmetry is broken in an arbitrary model. Recently, Witten proposed a topological invariant, the Witten index ..delta.. which counts the number of bosons minus the number of fermions having ground state energy zero. Since if supersymmetry is broken, the ground state energy cannot be zero, one expects if ..delta.. is not zero, SUSY is preserved and the theory is not a good candidate for a realistic model. In this study we evaluate ..delta.. for several examples, and show some unexpected peculiarities of the Witten index for certain choice of superpotentials W(x). We also discuss two other nonperturbative methods of studying supersymmetry breakdown. One involves relating supersymmetric quantum mechanics to a stochastic classical problem and the other involves considering a discrete (but not supersymmetric) version of the theory and studying its behavior as one removes the lattice cuttoff. In this survey we review the Hamiltonian and path integral approaches to supersymmetric quantum mechanics. We then discuss the related path integrals for the Witten Index and for stochastic processes and show how they are indications for supersymmetry breakdown. We then discuss a system where the superpotential W(x) has assymetrical values at +-infinity. We finally discuss nonperturbative strategies for studying supersymmetry breakdown based on introducing a lattice and studying the behavior of the ground state energy as the lattice cutoff is removed. 17 references.
Higgs Bosons in the Next-to-Minimal Supersymmetric Standard Model at the LHC
Ellwanger, Ulrich
2011-01-01
We review possible properties of Higgs bosons in the NMSSM, which allow to discriminate this model from the MSSM: masses of mostly Standard-Model-like Higgs bosons at or above 140 GeV, or enhanced branching fractions into two photons, or Higgs-to-Higgs decays. In the case of a Standard-Model-like Higgs boson above 140 GeV, it is necessarily accompagnied by a lighter state with a large gauge singlet component. Examples for such scenarios are presented. Available studies on Higgs-to-Higgs decay...
Supersymmetric Froggatt-Nielsen Models with Baryon- and Lepton-Number Violation
Dreiner, H K; Thormeier, Marc
2004-01-01
We systematically investigate the embedding of U(1)_X Froggatt-Nielsen models in local supersymmetry. We restrict ourselves to models with a single flavon field. We do not impose a discrete symmetry by hand, e.g. R-parity, baryon-parity or lepton-parity. Thus we determine the order of magnitude of the baryon- and/or lepton violating coupling constants through the Froggatt-Nielsen mechanism. We then scrutinize whether the predicted coupling constants are in accord with weak or GUT scale constraints. Many models turn out to be incompatible.
Fixing the EW scale in supersymmetric models after the Higgs discovery
Ghilencea, D. M.
2013-11-01
TeV-scale supersymmetry was originally introduced to solve the hierarchy problem and therefore fix the electroweak (EW) scale in the presence of quantum corrections. Numerical methods testing the SUSY models often report a good likelihood L (or χ2=-2ln L) to fit the data including the EW scale itself (mZ0) with a simultaneously large fine-tuning i.e. a large variation of this scale under a small variation of the SUSY parameters. We argue that this is inconsistent and we identify the origin of this problem. Our claim is that the likelihood (or χ2) to fit the data that is usually reported in such models does not account for the χ2 cost of fixing the EW scale. When this constraint is implemented, the likelihood (or χ2) receives a significant correction (δχ2) that worsens the current data fits of SUSY models. We estimate this correction for the models: constrained MSSM (CMSSM), models with non-universal gaugino masses (NUGM) or higgs soft masses (NUHM1, NUHM2), the NMSSM and the general NMSSM (GNMSSM). For a higgs mass mh≈126 GeV, one finds that in these models δχ2/n⩾1.5 (≈1 for GNMSSM), which violates the usual condition of a good fit (total χ2/n≈1) already before fitting observables other than the EW scale itself (n=number of degrees of freedom). This has (negative) implications for SUSY models and it is suggested that future data fits properly account for this effect, if one remains true to the original goal of SUSY. Since the expression of δχ2 that emerges from our calculation depends on a familiar measure of fine-tuning, one concludes that fine-tuning is an intrinsic part of the likelihood to fit the data that includes the EW scale (mZ0).
Fixing the EW scale in supersymmetric models after the Higgs discovery
Ghilencea, D M
2013-01-01
TeV-scale supersymmetry was originally introduced to solve the hierarchy problem and therefore fix the electroweak (EW) scale in the presence of quantum corrections. Numerical methods testing the SUSY models often report a good likelihood L (or chi^2=-2ln L) to fit the data {\\it including} the EW scale itself (m_Z^0) with a {\\it simultaneously} large fine-tuning i.e. a large variation of this scale under a small variation of the SUSY parameters. We argue that this is inconsistent and we identify the origin of this problem. Our claim is that the likelihood (or chi^2) to fit the data that is usually reported in such models does not account for the chi^2 cost of fixing the EW scale. When this constraint is implemented, the likelihood (or chi^2) receives a significant correction (delta_chi^2) that worsens the current data fits of SUSY models. We estimate this correction for the models: constrained MSSM (CMSSM), models with non-universal gaugino masses (NUGM) or higgs soft masses (NUHM1, NUHM2), the NMSSM and the ...
Anagnostopoulos, Konstantinos N; Nishimura, Jun
2012-01-01
The IKKT or IIB matrix model has been postulated to be a non perturbative definition of superstring theory. It has the attractive feature that spacetime is dynamically generated, which makes possible the scenario of dynamical compactification of extra dimensions, which in the Euclidean model manifests by spontaneously breaking the SO(10) rotational invariance (SSB). In this work we study using Monte Carlo simulations the 6 dimensional version of the Euclidean IIB matrix model. Simulations are found to be plagued by a strong complex action problem and the factorization method is used for effective sampling and computing expectation values of the extent of spacetime in various dimensions. Our results are consistent with calculations using the Gaussian Expansion method which predict SSB to SO(3) symmetric vacua, a finite universal extent of the compactified dimensions and finite spacetime volume.
Two-Dimensional Supersymmetric Sigma Models on Almost-Product Manifolds and Non-Geometry
Stojevic, V.
2010-01-01
We show that the superconformal symmetries of the (1,1) sigma model decompose into a set of more refined symmetries when the target space admits projectors $P_{\\pm}$, and the orthogonal complements $Q_{\\pm}$, covariantly constant with respect to the two natural torsionful connections $\
E Coniavitis; A Ferrari
2007-12-01
The minimal supersymmetric extension of the standard model (MSSM) predicts the existence of new charged and neutral Higgs bosons. The pair creation of these new particles at the multi-TeV + - compact linear collider (CLIC), followed by decays into standard model particles, were simulated along with the corresponding background. High-energy beam-beam effects such as ISR, beamstrahlung and hadronic background were included. We have investigated the possibility of using the ratio between the number of events found in various decay channels to determine the MSSM parameter tan and we have derived the corresponding statistical error from the uncertainties on the measured cross-sections and Higgs boson masses.
Fractional supersymmetric Liouville theory and the multi-cut matrix models
Irie, Hirotaka
2009-01-01
We argue that the non-critical version of the k-fractional superstring theory can be described with the k-cut critical points of the matrix models. In particular we show that, from the spectrum structure of fractional super-Liouville theory, (p,q) minimal fractional superstrings live in the Z_k-symmetry breaking critical points of the k-cut two-matrix models, and that the operator contents and string susceptibility coincide in both sides. By using this correspondence, we also propose the set of primary operators of the fractional superconformal ghost system which consistently gives the correct gravitational scaling critical exponents of the on-shell vertex operators.
Fractional supersymmetric Liouville theory and the multi-cut matrix models
Irie, Hirotaka
2009-10-01
We point out that the non-critical version of the k-fractional superstring theory can be described by k-cut critical points of the matrix models. In particular, in comparison with the spectrum structure of fractional super-Liouville theory, we show that (p,q) minimal fractional superstring theories appear in the Z-symmetry breaking critical points of the k-cut two-matrix models and the operator contents and string susceptibility coincide on both sides. By using this correspondence, we also propose a set of primary operators of the fractional superconformal ghost system which consistently produces the correct gravitational scaling critical exponents of the on-shell vertex operators.
Flowering to bloom of PeV scale supersymmetric left–right symmetric models
Urjit A Yajnik; Anishnu Sarkar; Sasmita Mishra; Debasish Borah
2016-02-01
Unified models incorporating right-handed neutrino in a symmetric way generically possess parity symmetry. If this is broken spontaneously, it results in the formation of domain walls in the early Universe, whose persistence is unwanted. A generic mechanism for the destabilization of such walls is a small pressure difference signalled by difference in free energy across the walls. It is interesting to explore the possibility of such effects in conjunction with the effects that break supersymmetry in a phenomenologically acceptable way. This possibility when realized in the context of several scenarios of supersymmetry breaking, leads to an upper bound on the scale of spontaneous parity breaking, often much lower than the GUT scale. In the left–right symmetric models studied, the upper bound is no higher than 1011 GeV but a scale as low as 105 GeV is acceptable.
The Galactic Center Region Gamma Ray Excess from A Supersymmetric Leptophilic Higgs Model
Marshall, Gardner
2011-01-01
In a recent paper by Hooper and Goodenough, data from the Fermi Gamma Ray Telescope was analyzed and an excess of gamma rays was found in the emission spectrum from the Galactic Center Region. Hooper and Goodenough show that the excess can be well explained by 7-10 GeV annihilating dark matter with a power law density profile if the dark matter annihilates predominantly to tau pairs. In this paper we present such a dark matter model by extending the MSSM to include four Higgs doublets and one scalar singlet. A Z2 symmetry is imposed that enforces a Yukawa structure so that the up quarks, down quarks, and leptons each receive mass from a distinct doublet. This leads to an enhanced coupling of scalars to leptons and allows the model to naturally achieve the required phenomenology in order to explain the gamma ray excess. Our model yields the correct dark matter thermal relic density and avoids collider bounds from measurements of the Z width as well as direct production at LEP.
Neutrino Mass and Proton Decay in a Realistic Supersymmetric SO(10) Model
Severson, Matthew
2016-01-01
This work presents a complete analysis of fermion fitting and proton decay in a SUSY $SO(10)$ model previously suggested by Dutta, Mimura, and Mohapatra. A key question in any grand unified theory is whether it satisfies the experimental lower limits on proton partial lifetimes. In generic models, substantial fine-tuning is required among GUT-scale parameters to satisfy the limits. In the proposed model, the ${\\bf 10}$, $\\overline{\\bf{126}}$, and ${\\bf 120}$ Yukawa couplings contributing to fermion masses have restricted textures intended to give favorable results for proton lifetime, while still giving rise to a realistic fermion sector, without the need for fine-tuning, even for large $\\tan\\beta$, and for either type-I or type-II dominance in the neutrino mass matrix. In this thesis, I investigate the above hypothesis at a strict numerical level of scrutiny; I obtain a valid fit for the entire fermion sector for both types of seesaw dominance, including $\\theta_{13}$ in good agreement with the most recent d...
Axion and neutrino physics in a U (1 )-enhanced supersymmetric model
Ahn, Y. H.
2017-07-01
Motivated by the flavored Peccei-Quinn symmetry for unifying the flavor physics and string theory, we construct an explicit model by introducing a U (1 ) symmetry such that the U (1 )X-[gravity]2 anomaly-free condition together with the standard model flavor structure demands additional sterile neutrinos as well as no axionic domain-wall problem. Such additional sterile neutrinos play the role of realizing baryogenesis via a new Affleck-Dine leptogenesis. We provide grounds for interpreting the U (1 )X symmetry as a fundamental symmetry of nature. The model will resolve rather recent but fast-growing issues in astroparticle physics, including leptonic mixings and C P violation in neutrino oscillation, high-energy neutrinos, QCD axions, and axion cooling of stars. The QCD axion decay constant, through its connection to the astrophysical constraints of stellar evolution and the SM fermion masses, is shown to be fixed at FA=1.30-0.54+0.66×1 09 GeV (consequently, its mass is ma=4.3 4-1.49+3.37 meV and the axion-photon coupling is |ga γ γ|=1.30-0.45+1.01×10-12 GeV-1 ). Interestingly enough, we show that neutrino oscillations at low energies could be connected to astronomical-scale baseline neutrino oscillations. The model predicts the nonobservational neutrinoless double beta (0 ν β β ) decay rate as well as a remarkable pattern between the leptonic Dirac C P phase (δC P) and the atmospheric mixing angle (θ23); e.g., δC P≃22 0 ° - 24 0 ° , 120°-140° for θ23=42.3 ° for normal mass ordering, and δC P≃28 3 ° , 250°, 100°, 70° for θ23=49.5 ° for the inverted one. We stress that future measurements on the θ23, 0 ν β β decay rate, the sum of active neutrino masses, the track-to-shower ratio of a cosmic neutrino, astrophysical constraints on axions, QCD axion mass, and the axion-photon coupling are of importance to test the model in the near future.
A supersymmetric standard model from a local E{sub 6} GUT
Braam, Felix Klaus
2012-02-15
In this thesis we have investigated to what extent the exceptional Lie-group E{sub 6} can serve as unified gauge group. In the presence of the full E{sub 6} matter content, unifcation can be realized by increasing the degree of gauge symmetry above some intermediate scale. We found that a full E{sub 6} gauge invariant theory is disfavoured by phenomenological observations like proton stability and the smallness of flavour changing neutral currents. An appropriate framework to embed E{sub 6} into a model for particle physics are higher dimensional orbifold constructions, where E{sub 6} is the gauge group in the bulk and the intermediate symmetry group is the common subset of E{sub 6} subgroups residing at the fixed-points of the orbifold. In this way the degree of symmetry in four space-time dimensions is reduced, such that the operators leading to the aforementioned dsastrous phenomenological consequences can be forbidden independently. In order to derive the implications of the model for the current experiments at the Large Hadron Collider (LHC), we developed an automated spectrum generator. It uses Monte-Carlo Markov-Chain techniques to cope with the high dimensionality of the space of input parameters and the complex interdependencies in the evolution of the Lagrangian parameters from the orbifold compactification scale to the TeV scale. For the spectra obtained with this program, we performed Monte-Carlo simulations of the production and decay of the Z{sup '} boson stemming from the additional U(1){sup '}, using our own implementation of the model into the event generator WHIZARD.
Ghost cohomologies and new discrete states in supersymmetric c=1 model
Deeb, Omar El
2014-01-01
As of today, string theory appears to be one of the most promising physical models unifying the fundamental interactions in nature, such as electromagnetic (gauge) interactions and the gravity. While the perturbative theory of strings appears to be well explored by now, we still lack an adequate formulation of string-theoretic formalism in the non-perturbative, or strongly coupled regime. One of the approaches, allowing us to explore the non-perturbative dynamics of strings (as well as of other physical theories with gauge degrees of freedom) is the formalism of ghost cohomologies, studied in this thesis. This approach is based on the fact that virtually all the crucial information on non-perturbative physics of gauge theories,but not manifestly gauge-invariant. Typically, these operators belong to a very special sector of the Hilbert space of gauge theories, where the matter and the ghost degrees of freedom are mixed. These physical operators are defined as elements of ghost cohomologies, studied in this the...
Decaying Dark Matter in Supersymmetric Model and Cosmic-Ray Observations
Ishiwata, Koji; Moroi, Takeo
2010-01-01
We study cosmic-rays in decaying dark matter scenario, assuming that the dark matter is the lightest superparticle and it decays through a R-parity violating operator. We calculate the fluxes of cosmic-rays from the decay of the dark matter and those from the standard astrophysical phenomena in the same propagation model using the GALPROP package. We reevaluate the preferred parameters characterizing standard astrophysical cosmic-ray sources with taking account of the effects of dark matter decay. We show that, if energetic leptons are produced by the decay of the dark matter, the fluxes of cosmic-ray positron and electron can be in good agreements with both PAMELA and Fermi-LAT data in wide parameter region. It is also discussed that, in the case where sizable number of hadrons are also produced by the decay of the dark matter, the mass of the dark matter is constrained to be less than 200-300 GeV in order to avoid the overproduction of anti-proton. We also show that the cosmic gamma-ray flux can be consiste...
Chatrchyan, S; Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Bergauer, T.; Dragicevic, M.; Eroe, J.; Fabjan, C.; Friedl, M.; Fruehwirth, R.; Thyssen, F.; Fisk, I.; Freeman, J; Gao, Y.
2011-01-01
A search for neutral minimal supersymmetric standard model (MSSM) Higgs bosons in pp collisions at the LHC at a center-of-mass energy of 7 TeV is presented. The results are based on a data sample corresponding to an integrated luminosity of 36 pb(-1) recorded by the CMS experiment. The search uses decays of the Higgs bosons to tau pairs. No excess is observed in the tau-pair invariant-mass spectrum. The resulting upper limits on the Higgs boson production cross section times branching fractio...
Bednyakov, V A; Kovalenko, S G
1994-01-01
The top quark mass values from the CDF Collaboration and the precision electroweak data at LEP combined with the bottom mass value allow to establish bounds on the parameter tan beta in the minimal supersymmetric standard model (MSSM) independent of the soft supersymmetry breaking parameters. We find: 0.96 1, where radiative electroweak symmetry breaking is possible. Assuming electroweak symmetry breaking leads to: tan beta=1.2 +- 0.2, if one neglects the high tan beta solution, which is unlikely due to proton lifetime limits.
Relation Between the Pole Mass and MS Mass of Top Quark in Supersymmetric QCD
CHEN Shao-Long; FENG Tai-Fu; LI Xue-Qian
2001-01-01
We discuss the relation between the pole mass and MS mass of top quark in the framework of the supersymmetric QCD. We find that the supersymmetric contributions are comparable to those of the standard model.
Relation Between the Pole Mass and MS Mass of Top Quark in Supersymmetric QCD
CHENShao－Long; FENGTai－Fu; 等
2001-01-01
We discuss the relation between the pole mass and MS mass of top quark in the framework of the supersymmetric QCD.We find that the supersymmetric contributions are comparable to those of the standard model.
Supersymmetric Optical Structures
Miri, Mohammad-Ali; El-Ganainy, Ramy; Christodoulides, Demetrios N
2013-01-01
We show that supersymmetry can provide a versatile platform in synthesizing a new class of optical structures with desired properties and functionalities. By exploiting the intimate relationship between superpatners, one can systematically construct index potentials capable of exhibiting the same scattering and guided wave characteristics. In particular, in the Helmholtz regime, we demonstrate that one-dimensional supersymmetric pairs display identical reflectivities and transmittivities for any angle of incidence. Optical SUSY is then extended to two-dimensional systems where a link between specific azimuthal mode subsets is established. Finally we explore supersymmetric photonic lattices where discreteness can be utilized to design lossless integrated mode filtering arrangements.
Allahverdi, Rouzbeh; Dutta, Bhaskar; Gao, Yu
2014-01-01
In this paper, we study the prospects for determining the nature of neutrinos in the context of a supersymmetric $B-L$ extension of the standard model by using dark matter indirect detection signals and bounds on $N_{\\text{eff}}$ from the cosmic microwave background data. The model contains two new dark matter candidates whose dominant annihilation channels produce more neutrinos than neutralino dark matter in the minimal supersymmetric standard model. The photon and neutrino counts may then be used to discriminate between the two models. If the dark matter comes from the B-L sector, its indirect signals and impact on the cosmic microwave background can shed light on the nature of the neutrinos. When the light neutrinos are of Majorana type, the indirect neutrino signal from the Sun and the galactic center may show a prompt neutrino box-feature, as well as an earlier cut-off in both neutrino and gamma ray energy spectra. When the light neutrinos are of Dirac type, their contribution to the effective number of...
Bubbles of nothing and supersymmetric compactifications
Blanco-Pillado, Jose J. [IKERBASQUE, Basque Foundation for Science, 48011, Bilbao (Spain); Department of Theoretical Physics, University of the Basque Country UPV/EHU,48080 Bilbao (Spain); Shlaer, Benjamin [Department of Physics, University of Auckland,Private Bag 92019, Auckland (New Zealand); Institute of Cosmology, Department of Physics and Astronomy,Tufts University, Medford, MA 02155 (United States); Sousa, Kepa [Department of Theoretical Physics, University of the Basque Country UPV/EHU,48080 Bilbao (Spain); Instituto de Fisica Teorica UAM-CSIC, Universidad Autonoma de Madrid,Cantoblanco, 28049 Madrid (Spain); Urrestilla, Jon [Department of Theoretical Physics, University of the Basque Country UPV/EHU,48080 Bilbao (Spain)
2016-10-03
We investigate the non-perturbative stability of supersymmetric compactifications with respect to decay via a bubble of nothing. We show examples where this kind of instability is not prohibited by the spin structure, i.e., periodicity of fermions about the extra dimension. However, such “topologically unobstructed” cases do exhibit an extra-dimensional analog of the well-known Coleman-De Luccia suppression mechanism, which prohibits the decay of supersymmetric vacua. We demonstrate this explicitly in a four dimensional Abelian-Higgs toy model coupled to supergravity. The compactification of this model to M{sub 3}×S{sub 1} presents the possibility of vacua with different windings for the scalar field. Away from the supersymmetric limit, these states decay by the formation of a bubble of nothing, dressed with an Abelian-Higgs vortex. We show how, as one approaches the supersymmetric limit, the circumference of the topologically unobstructed bubble becomes infinite, thereby preventing the realization of this decay. This demonstrates the dynamical origin of the decay suppression, as opposed to the more familiar argument based on the spin structure. We conjecture that this is a generic mechanism that enforces stability of any topologically unobstructed supersymmetric compactification.
Fermions on the worldsheet of effective strings via coset construction
Mohsen, Ali
2016-05-01
In this paper the detailed Coleman-Callan-Wess-Zumino procedure for introducing fermions on the world sheet of a string propagating in flat space-time is presented. The theory of nonlinear realizations is used to derive the transformation as well as the interactions of fermionic matter fields under arbitrary spinorial representations of the unbroken subgroup. This demonstrates that even for nonsupersymmetric spinors, the interactions are still severely restricted by the nonlinearly realized symmetry. We also explain how supersymmetric models provide an example for this construction with Goldstinos as matter fields, and how one can use the κ -symmetry of the Green Schwarz action in particular, to verify this nonlinear transformation for a specific matter field representation. We finally restrict the target space dimension without reference to supersymmetry, but rather by imposing one-loop integrability on a fermionic string that nonlinearly realizes Poincare symmetry. This singles out the critical dimension D =10 for heterotic, Green-Schwarz and Ramond-Neveu-Schwarz supersymmetric strings.
Supersymmetric heterotic string backgrounds
Gran, U.; Papadopoulos, G.; Roest, D.; Cvetič, M.
2007-01-01
We present the main features of the solution of the gravitino and dilatino Killing spinor equations derived in hep-th/0510176 and hep-th/0703143 which have led to the classification of geometric types of all type I backgrounds. We then apply these results to the supersymmetric backgrounds of the het
Search for supersymmetric Higgs signatures at the LHC
Rompotis, Nikolaos; The ATLAS collaboration
2015-01-01
This talk reviews the searches for supersymmetric Higgs bosons signatures at the LHC after Run-I. Searches for the Higgs bosons of the minimal supersymmetric Standard Model (MSSM) have been spearheaded in ATLAS and CMS by $h/H/A\\to \\tau\\tau$ and $H^{\\pm}\\to \\tau\
What if the Higgsino is the lightest supersymmetric particles
Haber, H.E.
1985-11-01
A pedagogical introduction to the mixing of neutral gauginos and Higgsinos in supersymmetric models is given. The possibility that the Higgsino (rather than the photino) is the lightest supersymmetric particle is considered and implications for phenomenology are discussed with some emphasis on signatures of supersymmetry in Z decays. Some related aspects of Higgs boson detection in Z decays are mentioned.
Supersymmetric photonic signals at LEP
López, J; Zichichi, Antonino
1996-01-01
We explore and contrast the single-photon and diphoton signals expected at LEP 2, that arise from neutralino-gravitino (e^+ e^- -> chi + gravitino -> gamma + E_miss) and neutralino-neutralino (e^+ e^- -> chi + chi -> gamma + gamma + E_miss) production in supersymmetric models with a light gravitino. LEP 1 limits imply that one may observe either one, but not both, of these signals at LEP 2, depending on the values of the neutralino and gravitino masses: single-photons for m_chi > Mz and m_gravitino < 3 x 10^-5 eV; diphotons for m_chi < Mz and all allowed values of m_gravitino.
Decoupling of Supersymmetric Particles in the MSSM
Dobado, A; Peñaranda, S
1998-01-01
A heavy supersymmetric spectrum at the Minimal Supersymmetric Standard Model is considered and the decoupling from the low energy electroweak scale is analyzed. A formal and partial proof of decoupling of supersymmetric particles in the limit where their masses are larger than the electroweak scale is performed by integrating out all the sparticles to one loop and by evaluating the effective action for the standard electroweak gauge bosons $W^{\\pm}, Z$ and two-point functions of the electroweak gauge bosons and the $S, T$ and $U$ parameters, to be valid in that limit, are also presented. A discussion on how the decoupling takes place in terms of both the physical sparticle masses and the non-physical mass parameters as the $\\mu$-parameter and the soft-breaking parameters is included.
The many faces of the superworld Yuri Golfand Memorial Volume
2000-01-01
This invaluable volume is dedicated to the memory of Yuri Golfand, one of the discoverers of supersymmetry. Together with his student, he constructed in 1970 the superextension of the Poincaré algebra and obtained the first four-dimensional supersymmetric field theory, a version of supersymmetric QED. Golfand died in 1994 in Israel.Did the pioneers of supersymmetry - Neveu, Schwarz, Ramond, Golfand, Volkov, Wess, Zumino and others - foresee in the early 1970's that they would be opening to us the gates of the superworld? The superworld will become one of the most important components of our un
BRST formulation of 4-monopoles
Gianvittorio, R; Restuccia, A
1996-01-01
A supersymmetric gauge invariant action is constructed over any 4-dimensional Riemannian manifold describing Witten's theory of 4-monopoles. The topological supersymmetric algebra closes off-shell. The multiplets include the auxiliary fields and the Wess-Zumino fields in an unusual way, arising naturally from BRST gauge fixing. A new canonical approach over Riemann manifolds is followed, using a Morse function as an euclidean time and taking into account the BRST boundary conditions that come from the BFV formulation. This allows a construction of the effective action starting from gauge principles.
Softly Broken Supersymmetric Gauge Theories through Compactifications
Takenaga, K
1998-01-01
Effects of boundary conditions of fields for compactified space directions on the supersymmetric gauge theories are discussed. For general and possible boundary conditions the supersymmetry is explicitly broken to yield universal soft supersymmetry breaking terms, and the gauge symmetry of the theory can also be broken through the dynamics of non-integrable phases, depending on number and the representation under the gauge group of matters. The 4-dimensional supersymmetric QCD is studied as a toy model when one of the space coordinates is compactified on $S^1$.
Renormalizability of Supersymmetric Group Field Cosmology
Upadhyay, Sudhaker
2014-01-01
In this paper we consider the gauge invariant third quantized model of supersymmetric group field cosmology. The supersymmetric BRST invariance for such theory in non-linear gauge is also analysed. The path integral formulation to the case of a multiverse made up of homogeneous and isotropic spacetimes filled with a perfect fluid is presented. The renormalizability for the scattering of universes in multiverse are established with suitably constructed master equations for connected diagrams and proper vertices. The Slavnov-Taylor identities for this theory hold to all orders of radiative corrections.
Renormalizability of supersymmetric group field cosmology
Upadhyay, Sudhaker
2014-03-01
In this paper we consider the gauge invariant third quantized model of supersymmetric group field cosmology. The supersymmetric BRST invariance for such theory in non-linear gauge is also analysed. The path integral formulation to the case of a multiverse made up of homogeneous and isotropic spacetimes filled with a perfect fluid is presented. The renormalizability for the scattering of universes in multiverse are established with suitably constructed master equations for connected diagrams and proper vertices. The Slavnov-Taylor identities for this theory hold to all orders of radiative corrections.
Supersymmetric radiative corrections at large tan {beta}
Logan, H.E.
2001-02-20
In the minimal supersymmetric extension of the Standard Model (MSSM), fermion masses and Yukawa couplings receive radiative corrections at one loop from diagrams involving the supersymmetric particles. The corrections to the relation between down-type fermion masses and Yukawa couplings are enhanced by tan {beta}, which makes them potentially very significant at large tan {beta}. These corrections affect a wide range of processes in the MSSM, including neutral and charged Higgs phenomenology, rare B meson decays, and renormalization of the CKM matrix. We give a pedagogical review of the sources and phenomenological effects of these corrections.
Exact four-dimensional dyonic black holes and Bertotti-Robinson spacetimes in string theory
Lowe, David A.; Strominger, Andrew
1994-09-01
Conformal field theories corresponding to two-dimensional electrically charged black holes and to two-dimensional anti-de Sitter space with a covariantly constant electric field are simply constructed as SL(2,openR)/openZ Wess-Zumino-Witten coset models. Four-dimensional spacetime solutions are obtained by tensoring these two-dimensional theories with SU(2)/Z(m) coset models. These describe a family of dyonic black holes and the Bertotti-Robinson universe.
Chiral Decomposition For Non-Abelian Bosons
Braga, N R F; Braga, Nelson R. F.; Wotzasek, Clovis
1996-01-01
We study the non-abelian extension for the splitting of a scalar field into chiral components. Using this procedure we find a non ambiguous way of coupling a non abelian chiral scalar field to gravity. We start with a (non-chiral) WZW model covariantly coupled to a background metric and, after the splitting, arrive at two chiral Wess-Zumino-Witten (WZW) models coupled to gravity.
Duru, Firdevs
2007-01-01
This thesis consists of two main parts: R&D; studies done on the Compact Muon Solenoid (CMS) Hadronic Calorimeter (HCAL) and physics simulations on the Higgs boson for a Minimal Supersymmetric Standard Model (MSSM) and a Standard Model (SM) channel. In the first part, the air core light guides used in the read-out system of the Hadronic Forward (HF) calorimeter and the reflective materials used in them are studied. Then, tests and simulations were performed to find the most efficient way to collect Cerenkov light from the quartz plates, which are proposed as a substitute for the scintillator tiles in the Hadronic Endcap (HE) calorimeter due to radiation damage problems. In the second part physics simulations and their results are presented. The MSSM channel H/A[arrow right]ττ [arrow right]l l v v v v is studied to investigate the jet and missing transverse energy (MET) reconstruction of the CMS detector. The effects of the jet and MET corrections on the Higgs boson mass reconstruction are investigated. ...
N=1 Supersymmetric Boundary Bootstrap
Toth, G Z
2004-01-01
We investigate the boundary bootstrap programme for finding exact reflection matrices of integrable boundary quantum field theories with N=1 boundary supersymmetry. The bulk S-matrix and the reflection matrix are assumed to take the form S=S_1S_0, R=R_1R_0, where S_0 and R_0 are the S-matrix and reflection matrix of some integrable non-supersymmetric boundary theory that is assumed to be known, and S_1 and R_1 describe the mixing of supersymmetric indices. Under the assumption that the bulk particles transform in the kink and boson/fermion representations and the ground state is a singlet we present rules by which the supersymmetry representations and reflection factors for excited boundary bound states can be determined. We apply these rules to the boundary sine-Gordon model, to the boundary a_2^(1) and a_4^(1) affine Toda field theories, to the boundary sinh-Gordon model and to the free particle.
One-loop amplitudes of winding strings in AdS$_3$ and the Coulomb gas approach
Giribet, Gaston
2015-01-01
We discuss a Coulomb gas realization of $n$-point correlation functions in the $SL(2,\\mathbb{R})$ Wess-Zumino-Witten (WZW) model that is suitable to compute scattering amplitudes of winding strings in 3-dimensional Anti-de Sitter space at tree-level and one-loop. This is a refined version of previously proposed free-field realizations that, among other features, accomplishes to make the $H_3^+$ WZW-Liouville correspondence manifest.
Torsion and geometrostasis in covariant superstrings
Zachos, C.
1985-01-01
The covariant action for freely propagating heterotic superstrings consists of a metric and a torsion term with a special relative strength. It is shown that the strength for which torsion flattens the underlying 10-dimensional superspace geometry is precisely that which yields free oscillators on the light cone. This is in complete analogy with the geometrostasis of two-dimensional sigma-models with Wess-Zumino interactions. 13 refs.
Acciarri, M; Adriani, O; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Ambrosi, G; Anderhub, H; Andreev, V P; Angelescu, T; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Baksay, L; Balandras, A; Ball, R C; Banerjee, S; Banerjee, Sw; Barczyk, A; Barillère, R; Barone, L; Bartalini, P; Basile, M; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Bhattacharya, S; Biasini, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böhm, A; Boldizsar, L; Borgia, B; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brigljevic, V; Brochu, F; Buffini, A; Buijs, A; Burger, J D; Burger, W J; Busenitz, J K; Button, A M; Cai, X D; Campanelli, M; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Castellini, G; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada-Canales, M; Cesaroni, F; Chamizo-Llatas, M; Chang, Y H; Chaturvedi, U K; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chéreau, X J; Chiefari, G; Cifarelli, Luisa; Cindolo, F; Civinini, C; Clare, I; Clare, R; Coignet, G; Colijn, A P; Colino, N; Costantini, S; Cotorobai, F; Cozzoni, B; de la Cruz, B; Csilling, Akos; Cucciarelli, S; Dai, T S; van Dalen, J A; D'Alessandro, R; De Asmundis, R; Déglon, P L; Degré, A; Deiters, K; Della Volpe, D; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Van Dierendonck, D N; Di Lodovico, F; Dionisi, C; Dittmar, Michael; Dominguez, A; Doria, A; Dova, M T; Duchesneau, D; Dufournaud, D; Duinker, P; Durán, I; El-Mamouni, H; Engler, A; Eppling, F J; Erné, F C; Extermann, Pierre; Fabre, M; Faccini, R; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, Marta; Ferguson, T; Ferroni, F; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisk, I; Forconi, G; Fredj, L; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gau, S S; Gentile, S; Gheordanescu, N; 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; Hasan, A; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hidas, P; Hirschfelder, J; Hofer, H; Holzner, G; Hoorani, H; Hou, S R; Iashvili, I; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Khan, R A; Kamrad, D; Kaur, M; Kienzle-Focacci, M N; Kim, D; Kim, D H; Kim, J K; Kim, S C; Kirkby, Jasper; Kiss, D; Kittel, E W; Klimentov, A; König, A C; Kopp, A; Koutsenko, V F; Kräber, M H; Krämer, R W; Krenz, W; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lassila-Perini, K M; Laurikainen, P; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Lee, H J; Le Goff, J M; Leiste, R; Leonardi, E; Levchenko, P M; Li Chuan; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Lübelsmeyer, K; Luci, C; Luckey, D; Lugnier, L; Luminari, L; Lustermann, W; Ma Wen Gan; Maity, M; Malgeri, L; Malinin, A; Maña, C; Mangeol, D J J; Marchesini, P A; Marian, G; Martin, J P; Marzano, F; Massaro, G G G; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Von der Mey, M; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Molnár, P; Monteleoni, B; Moulik, T; Muanza, G S; Muheim, F; Muijs, A J M; Musy, M; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Niessen, T; Nisati, A; Nowak, H; Oh, Yu D; Organtini, G; Ostonen, R; Oulianov, A; Palomares, C; Pandoulas, D; Paoletti, S; Paolucci, P; Paramatti, R; Park, H K; Park, I H; Pascale, G; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Peach, D; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pieri, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Postema, H; Pothier, J; Produit, N; Prokofev, D; Prokofiev, D O; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Raven, G; Razis, P A; Ren, D; Rescigno, M; Reucroft, S; Van Rhee, T; Riemann, S; Riles, K; Robohm, A; Rodin, J; Roe, B P; Romero, L; Rosca, A; Rosier-Lees, S; Rubio, Juan Antonio; Ruschmeier, D; Rykaczewski, H; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Sanders, M P; Sarakinos, M E; Schäfer, C; Shchegelskii, V; Schmidt-Kärst, S; Schmitz, D; Schopper, Herwig Franz; Schotanus, D J; Schwering, G; Sciacca, C; Sciarrino, D; Seganti, A; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A V; Siedenburg, T; Son, D; Smith, B; Spillantini, P; Steuer, M; Stickland, D P; Stone, A; Stone, H; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Suter, H; Swain, J D; Szillási, Z; Sztaricskai, T; Tang, X W; Tauscher, Ludwig; Taylor, L; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Uchida, Y; Ulbricht, J; Valente, E; 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; Vorvolakos, A; Wadhwa, M; Wallraff, W; Wang, M; Wang, X L; Wang, Z M; Weber, A; Weber, M; Wienemann, P; Wilkens, H; Wu, S X; Wynhoff, S; Xia, L; Xu, Z Z; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Ye, J B; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhu, G Y; Zhu, R Y; Zichichi, A; Ziegler, F; Zilizi, G; Zöller, M
1999-01-01
A search for the lightest neutral scalar and neutral pseudoscalar Higgs bosons in the Minimal Supersymmetric Standard Model is performed using 176.4 pb$^{-1}$ of integrated luminosity collected by L3 at a center-of-mass energy of 189 GeV. No signal is observed, and the data are consistent with the expected Standard Model background. Lower limits on the masses of the lightest neutral scalar and pseudoscalar Higgs bosons are given as a function of $\\tan\\beta$. Lower mass limits for $\\tan\\beta > 1$ are set at the 95\\% confidence level to be $m_{\\rm h} > 77.1$ GeV and $m_{\\rm A} > 77.1$ GeV.
Neutrino masses and mixing in supersymmetric theories
Sudhir K Vempati
2000-07-01
It has been known for sometime that supersymmetric theories with -parity violation provide a natural framework where small neutrino masses can be generated. We discuss neutrino masses and mixing in these theories in the presence of trilinear lepton number violating couplings. It will be shown that simultaneous solutions to solar and atmospheric neutrino problems can be realized in these models.
Quinto, A G
2016-01-01
We studied the Dynamical Symmetry Breaking (DSB) mechanism in a supersymmetric Chern-Simons theory in $\\left(2+1\\right)$ dimensions coupled to $N$ matter superfields in the superfield formalism. For this purpose, we developed a mechanism to calculate the effective superpotencial $K_{\\mathrm{eff}}\\left(\\sigma_{\\mathrm{cl}},\\alpha\\right)$, where $\\sigma_{\\mathrm{cl}}$ is a background superfield, and $\\alpha$ a gauge-fixing parameter that is introduced in the quantization process. The possible dependence of the effective potential on the gauge parameter have been studied in the context of quantum field theory. We developed the formalism of the Nielsen identities in the superfield language, which is the appropriate formalism to study DSB when the effective potential is gauge dependent. We also discuss how to calculate the effective superpotential via the Renormalization Group Equation (RGE) from the knowledge of the renormalization group functions of the theory, i.e., $\\beta$ functions and anomalous dimensions $\\...
Consistent quantization and symmetry structure of a non-Abelian chiral gauge theory
Shizuya, Ken-Ichi
1989-08-01
The SU(N) chiral Schwinger model with a Wess-Zumino term is studied by use of non-Abelian bosonization, the Becchi-Rouet-Stora formalism, and a dual transformation, and it is confirmed that this model is a sensible quantum theory in a certain range of the anomaly parameter a. The SU(N) gauge symmetry restored by the inclusion of the Wess-Zumino term gets spontaneously broken and the gauge field becomes massive. Left-handed fermions are found to be confined while right-handed fermions remain free and massless. For the specific value a=2, the symmetry of the model enlarges [to a U(N)×U(N) Kac-Moody symmetry]. It is shown by fermionization of the Wess-Zumino field that for a=2 this model is equivalent to massless two-dimensional QCD (QCD2) in the sense that they share the same gauge field and the same left-handed fermions. A dual transformation is used to cast the model into an equivalent nonlinear system of scalar fields only, which reveals the particle spectrum of the model.
Creutzig, Thomas
2009-06-15
In this thesis we initiate a systematic study of branes in Wess-Zumino-Novikov-Witten models with Lie supergroup target space. We start by showing that a branes' worldvolume is a twisted superconjugacy class and construct the action of the boundary WZNW model. Then we consider symplectic fermions and give a complete description of boundary states including twisted sectors. Further we show that the GL(1 vertical stroke 1) WZNW model is equivalent to symplectic fermions plus two scalars. We then consider the GL(1 vertical stroke 1) boundary theory. Twisted and untwisted Cardy boundary states are constructed explicitly and their amplitudes are computed. In the twisted case we find a perturbative formulation of the model. For this purpose the introduction of an additional fermionic boundary degree of freedom is necessary. We compute all bulk one-point functions, bulk-boundary two-point functions and boundary three-point functions. Logarithmic singularities appear in bulk-boundary as well as pure boundary correlation functions. Finally we turn to world-sheet and target space supersymmetric models. There is N=2 superconformal symmetry in many supercosets and also in certain supergroups. In the supergroup case we find some branes that preserve the topological A-twist and some that preserve the B-twist. (orig.)
Chatrchyan, S; Khachatryan, V; Sirunyan, A M; Tumasyan, A; Adam, W; Bergauer, T; Dragicevic, M; Erö, J; Fabjan, C; Friedl, M; Frühwirth, R; Ghete, V M; Hammer, J; Hänsel, S; Hoch, M; Hörmann, N; Hrubec, J; Jeitler, M; Kasieczka, G; Kiesenhofer, W; Krammer, M; Liko, D; Mikulec, I; Pernicka, M; Rohringer, H; Schöfbeck, R; Strauss, J; Teischinger, F; Wagner, P; Waltenberger, W; Walzel, G; Widl, E; Wulz, C-E; Mossolov, V; Shumeiko, N; Suarez Gonzalez, J; Benucci, L; De Wolf, E A; Janssen, X; Maes, T; Mucibello, L; Ochesanu, S; Roland, B; Rougny, R; Selvaggi, M; Van Haevermaet, H; Van Mechelen, P; Van Remortel, N; Blekman, F; Blyweert, S; D'Hondt, J; Devroede, O; Gonzalez Suarez, R; Kalogeropoulos, A; Maes, J; Maes, M; Van Doninck, W; Van Mulders, P; Van Onsem, G P; Villella, I; Charaf, O; Clerbaux, B; De Lentdecker, G; Dero, V; Gay, A P R; Hammad, G H; Hreus, T; Marage, P E; Thomas, L; Vander Velde, C; Vanlaer, P; Adler, V; Cimmino, A; Costantini, S; Grunewald, M; Klein, B; Lellouch, J; Marinov, A; McCartin, J; Ryckbosch, D; Thyssen, F; Tytgat, M; Vanelderen, L; Verwilligen, P; Walsh, S; Zaganidis, N; Basegmez, S; Bruno, G; Caudron, J; Ceard, L; Cortina Gil, E; De Favereau De Jeneret, J; Delaere, C; Favart, D; Giammanco, A; Grégoire, G; Hollar, J; Lemaitre, V; Liao, J; Militaru, O; Ovyn, S; Pagano, D; Pin, A; Piotrzkowski, K; Schul, N; Beliy, N; Caebergs, T; Daubie, E; Alves, G A; Damiao, D De Jesus; Pol, M E; Souza, M H G; Carvalho, W; Da Costa, E M; Martins, C De Oliveira; De Souza, S Fonseca; Mundim, L; Nogima, H; Oguri, V; Da Silva, W L Prado; Santoro, A; Do Amaral, S M Silva; Sznajder, A; De Araujo, F Torres Da Silva; Dias, F A; Tomei, T R Fernandez Perez; Gregores, E M; Lagana, C; Marinho, F; Mercadante, P G; Novaes, S F; Padula, Sandra S; Darmenov, N; Dimitrov, L; Genchev, V; Iaydjiev, P; Piperov, S; Rodozov, M; Stoykova, S; Sultanov, G; Tcholakov, V; Trayanov, R; Vankov, I; Dimitrov, A; Hadjiiska, R; Karadzhinova, A; Kozhuharov, V; Litov, L; Mateev, M; Pavlov, B; Petkov, P; Bian, J G; Chen, G M; Chen, H S; Jiang, C H; Liang, D; Liang, S; Meng, X; Tao, J; Wang, J; Wang, J; Wang, X; Wang, Z; Xiao, H; Xu, M; Zang, J; Zhang, Z; Ban, Y; Guo, S; Guo, Y; Li, W; Mao, Y; Qian, S J; Teng, H; Zhang, L; Zhu, B; Zou, W; Cabrera, A; Moreno, B Gomez; Rios, A A Ocampo; Oliveros, A F Osorio; Sanabria, J C; Godinovic, N; Lelas, D; Lelas, K; Plestina, R; Polic, D; Puljak, I; Antunovic, Z; Dzelalija, M; Brigljevic, V; Duric, S; Kadija, K; Morovic, S; Attikis, A; Galanti, M; Mousa, J; Nicolaou, C; Ptochos, F; Razis, P A; Finger, M; Finger, M; Assran, Y; Khalil, S; Mahmoud, M A; Hektor, A; Kadastik, M; Müntel, M; Raidal, M; Rebane, L; Azzolini, V; Eerola, P; Fedi, G; Czellar, S; Härkönen, J; Heikkinen, A; Karimäki, V; Kinnunen, R; Kortelainen, M J; Lampén, T; Lassila-Perini, K; Lehti, S; Lindén, T; Luukka, P; Mäenpää, T; Tuominen, E; Tuominiemi, J; Tuovinen, E; Ungaro, D; Wendland, L; Banzuzi, K; Korpela, A; Tuuva, T; Sillou, D; Besancon, M; Choudhury, S; Dejardin, M; Denegri, D; Fabbro, B; Faure, J L; Ferri, F; Ganjour, S; Gentit, F X; Givernaud, A; Gras, P; de Monchenault, G Hamel; Jarry, P; Locci, E; Malcles, J; Marionneau, M; Millischer, L; Rander, J; Rosowsky, A; Shreyber, I; Titov, M; Verrecchia, P; Baffioni, S; Beaudette, F; Benhabib, L; Bianchini, L; Bluj, M; Broutin, C; Busson, P; Charlot, C; Dahms, T; Dobrzynski, L; Elgammal, S; de Cassagnac, R Granier; Haguenauer, M; Miné, P; Mironov, C; Ochando, C; Paganini, P; Sabes, D; Salerno, R; Sirois, Y; Thiebaux, C; Wyslouch, B; Zabi, A; Agram, J-L; Andrea, J; Bloch, D; Bodin, D; Brom, J-M; Cardaci, M; Chabert, E C; Collard, C; Conte, E; Drouhin, F; Ferro, C; Fontaine, J-C; Gelé, D; Goerlach, U; Greder, S; Juillot, P; Karim, M; Le Bihan, A-C; Mikami, Y; Van Hove, P; Fassi, F; Mercier, D; Baty, C; Beauceron, S; Beaupere, N; Bedjidian, M; Bondu, O; Boudoul, G; Boumediene, D; Brun, H; Chierici, R; Contardo, D; Depasse, P; El Mamouni, H; Fay, J; Gascon, S; Ille, B; Kurca, T; Le Grand, T; Lethuillier, M; Mirabito, L; Perries, S; Sordini, V; Tosi, S; Tschudi, Y; Verdier, P; Lomidze, D; Anagnostou, G; Edelhoff, M; Feld, L; Heracleous, N; Hindrichs, O; Jussen, R; Klein, K; Merz, J; Mohr, N; Ostapchuk, A; Perieanu, A; Raupach, F; Sammet, J; Schael, S; Sprenger, D; Weber, H; Weber, M; Wittmer, B; Ata, M; Bender, W; Dietz-Laursonn, E; Erdmann, M; Frangenheim, J; Hebbeker, T; Hinzmann, A; Hoepfner, K; Klimkovich, T; Klingebiel, D; Kreuzer, P; Lanske, D; Magass, C; Merschmeyer, M; Meyer, A; Papacz, P; Pieta, H; Reithler, H; Schmitz, S A; Sonnenschein, L; Steggemann, J; Teyssier, D; Tonutti, M; Bontenackels, M; Davids, M; Duda, M; Flügge, G; Geenen, H; Giffels, M; Ahmad, W Haj; Heydhausen, D; Kress, T; Kuessel, Y; Linn, A; Nowack, A; Perchalla, L; Pooth, O; Rennefeld, J; Sauerland, P; Stahl, A; Thomas, M; Tornier, D; Zoeller, M H
2011-06-10
A search for neutral minimal supersymmetric standard model (MSSM) Higgs bosons in pp collisions at the LHC at a center-of-mass energy of 7 TeV is presented. The results are based on a data sample corresponding to an integrated luminosity of 36 pb(-1) recorded by the CMS experiment. The search uses decays of the Higgs bosons to tau pairs. No excess is observed in the tau-pair invariant-mass spectrum. The resulting upper limits on the Higgs boson production cross section times branching fraction to tau pairs, as a function of the pseudoscalar Higgs boson mass, yield stringent new bounds in the MSSM parameter space.
Aad, Georges; Abdallah, Jalal; Abdel Khalek, Samah; Abdinov, Ovsat; Aben, Rosemarie; Abi, Babak; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina; Abreu, Henso; Abreu, Ricardo; Abulaiti, Yiming; Acharya, Bobby Samir; Adamczyk, Leszek; Adams, David; Adelman, Jahred; Adomeit, Stefanie; Adye, Tim; Agatonovic-Jovin, Tatjana; Aguilar-Saavedra, Juan Antonio; Agustoni, Marco; Ahlen, Steven; Ahmadov, Faig; Aielli, Giulio; Akerstedt, Henrik; Åkesson, Torsten Paul Ake; Akimoto, Ginga; Akimov, Andrei; Alberghi, Gian Luigi; Albert, Justin; Albrand, Solveig; Alconada Verzini, Maria Josefina; Aleksa, Martin; Aleksandrov, Igor; Alexa, Calin; Alexander, Gideon; Alexandre, Gauthier; Alexopoulos, Theodoros; Alhroob, Muhammad; Alimonti, Gianluca; Alio, Lion; Alison, John; Allbrooke, Benedict; Allison, Lee John; Allport, Phillip; Aloisio, Alberto; Alonso, Alejandro; Alonso, Francisco; Alpigiani, Cristiano; Altheimer, Andrew David; Alvarez Gonzalez, Barbara; Alviggi, Mariagrazia; Amako, Katsuya; Amaral Coutinho, Yara; Amelung, Christoph; Amidei, Dante; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amram, Nir; Amundsen, Glenn; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Anduaga, Xabier; Angelidakis, Stylianos; Angelozzi, Ivan; Anger, Philipp; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antonaki, Ariadni; Antonelli, Mario; Antonov, Alexey; Antos, Jaroslav; Anulli, Fabio; Aoki, Masato; Aperio Bella, Ludovica; Apolle, Rudi; Arabidze, Giorgi; Aracena, Ignacio; Arai, Yasuo; Araque, Juan Pedro; Arce, Ayana; Arduh, Francisco Anuar; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnal, Vanessa; Arnold, Hannah; Arratia, Miguel; Arslan, Ozan; Artamonov, Andrei; Artoni, Giacomo; Asai, Shoji; Asbah, Nedaa; Ashkenazi, Adi; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astalos, Robert; Atkinson, Markus; Atlay, Naim Bora; Auerbach, Benjamin; Augsten, Kamil; Aurousseau, Mathieu; Avolio, Giuseppe; Axen, Bradley; Azuelos, Georges; Azuma, Yuya; Baak, Max; Baas, Alessandra; Bacci, Cesare; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Backus Mayes, John; Badescu, Elisabeta; Bagiacchi, Paolo; Bagnaia, Paolo; Bai, Yu; Bain, Travis; Baines, John; Baker, Oliver Keith; Balek, Petr; Balli, Fabrice; Banas, Elzbieta; Banerjee, Swagato; Bannoura, Arwa A E; Bansal, Vikas; Bansil, Hardeep Singh; Barak, Liron; Baranov, Sergei; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnes, Sarah Louise; Barnett, Bruce; Barnett, Michael; Barnovska, Zuzana; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartos, Pavol; Bartsch, Valeria; Bassalat, Ahmed; Basye, Austin; Bates, Richard; Batista, Santiago Juan; Batley, Richard; Battaglia, Marco; Battistin, Michele; Bauer, Florian; Bawa, Harinder Singh; Beattie, Michael David; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Bechtle, Philip; Beck, Hans Peter; Becker, Anne Kathrin; Becker, Sebastian; Beckingham, Matthew; Becot, Cyril; Beddall, Andrew; Beddall, Ayda; Bedikian, Sourpouhi; Bednyakov, Vadim; Bee, Christopher; Beemster, Lars; Beermann, Thomas; Begel, Michael; Behr, Katharina; Belanger-Champagne, Camille; Bell, Paul; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellerive, Alain; Bellomo, Massimiliano; Belotskiy, Konstantin; Beltramello, Olga; Benary, Odette; Benchekroun, Driss; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez Garcia, Jorge-Armando; Benjamin, Douglas; Bensinger, James; Bentvelsen, Stan; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Beringer, Jürg; Bernard, Clare; Bernat, Pauline; Bernius, Catrin; Bernlochner, Florian Urs; Berry, Tracey; Berta, Peter; Bertella, Claudia; Bertoli, Gabriele; Bertolucci, Federico; Bertsche, Carolyn; Bertsche, David; Besana, Maria Ilaria; Besjes, Geert-Jan; Bessidskaia, Olga; Bessner, Martin Florian; Besson, Nathalie; Betancourt, Christopher; Bethke, Siegfried; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianchini, Louis; Bianco, Michele; Biebel, Otmar; Bieniek, Stephen Paul; Bierwagen, Katharina; Biesiada, Jed; Biglietti, Michela; Bilbao De Mendizabal, Javier; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien
2014-01-01
A search for the neutral Higgs bosons predicted by the Minimal Supersymmetric Standard Model (MSSM) is reported. The analysis is performed on data from proton--proton collisions at a centre-of-mass energy of $8 TeV$ collected with the ATLAS detector at the Large Hadron Collider. The samples used for this search were collected in 2012 and correspond to integrated luminosities in the range 19.5 - 20.3 fb$^{-1}$. The MSSM Higgs bosons are searched for in the $\\tau\\tau$ final state. No significant excess over the expected background is observed, and exclusion limits are derived for the production cross section times branching fraction of a scalar particle as a function of its mass. The results are also interpreted in the MSSM parameter space for various benchmark scenarios.
AUTHOR|(SzGeCERN)678890
A search for the neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM), produced in proton-proton collisions recorded by the ATLAS detector, is pre-sented. The data correspond to an integrated luminosity of 20.3 fb −1 , with a center of mass energy of 8 TeV. The search focuses on final states where the Higgs bosons decay into a τ+ τ− pair, with one τ lepton decaying leptonically and the other hadronically. Two analyses are performed which separately target low-mass and high-mass Higgs bosons, with the former divided into two sub-channels based on the presence or absence of a b-jet in final state. No evidence of new Higgs bosons is found, and upper limits are set on the cross-section times branching ratio of such Higgs bosons, and on the MSSM parameters m A and tanβ.
Abazov V. M.; Abbott B.; Acharya B. S.; Adams M.; Adams T.; Alexeev G. D.; Alkhazov G.; Alton A.; Alverson G.; Aoki M.; Askew A.; Asman B.; Atkins S.; Atramentov O.; Augsten K.; Avila C.; BackusMayes J.; Badaud F.; Bagby L.; Baldin B.; Bandurin D. V.; Banerjee S.; Barberis E.; Baringer P.; Barreto J.; Bartlett J. F.; Bassler U.; Bazterra V.; Bean A.; Begalli M.; Belanger-Champagne C.; Bellantoni L.; Beri S. B.; Bernardi G.; Bernhard R.; Bertram I.; Besancon M.; Beuselinck R.; Bezzubov V. A.; Bhat P. C.; Bhatia S.; Bhatnagar V.; Blazey G.; Blessing S.; Bloom K.; Boehnlein A.; Boline D.; Boos E. E.; Borissov G.; Bose T.; Brandt A.; Brandt O.; Brock R.; Brooijmans G.; Bross A.; Brown D.; Brown J.; Bu X. B.; Buehler M.; Buescher V.; Bunichev V.; Burdin S.; Burnett T. H.; Buszello C. P.; Calpas B.; Camacho-Perez E.; Carrasco-Lizarraga M. A.; Casey B. C. K.; Castilla-Valdez H.; Chakrabarti S.; Chakraborty D.; Chan K. M.; Chandra A.; Chapon E.; Chen G.; Chevalier-Thery S.; Cho D. K.; Cho S. W.; Choi S.; Choudhary B.; Cihangir S.; Claes D.; Clutter J.; Cooke M.; Cooper W. E.; Corcoran M.; Couderc F.; Cousinou M. -C.; Croc A.; Cutts D.; Das A.; Davies G.; de Jong S. J.; De La Cruz-Burelo E.; Deliot F.; Demina R.; Denisov D.; Denisov S. P.; Desai S.; Deterre C.; DeVaughan K.; Diehl H. T.; Diesburg M.; Ding P. F.; Dominguez A.; Dorland T.; Dubey A.; Dudko L. V.; Duggan D.; Duperrin A.; Dutt S.; Dyshkant A.; Eads M.; Edmunds D.; Ellison J.; Elvira V. D.; Enari Y.; Evans H.; Evdokimov A.; Evdokimov V. N.; Facini G.; Ferbel T.; Fiedler F.; Filthaut F.; Fisher W.; Fisk H. E.; Fortner M.; Fox H.; Fuess S.; Garcia-Bellido A.; Garcia-Guerra G. A.; Gavrilov V.; Gay P.; Geng W.; Gerbaudo D.; Gerber C. E.; Gershtein Y.; Ginther G.; Golovanov G.; Goussiou A.; Grannis P. D.; Greder S.; Greenlee H.; Greenwood Z. D.; Gregores E. M.; Grenier G.; Gris Ph.; Grivaz J. -F.; Grohsjean A.; Gruenendahl S.; Gruenewald M. W.; Guillemin T.; Gutierrez G.; Gutierrez P.; Haas A.; Hagopian S.; Haley J.; Han L.; Harder K.; Harel A.; Hauptman J. M.; Hays J.; Head T.; Hebbeker T.; Hedin D.; Hegab H.; Heinson A. P.; Heintz U.; Hensel C.; Heredia-De La Cruz I.; Herner K.; Hesketh G.; Hildreth M. D.; Hirosky R.; Hoang T.; Hobbs J. D.; Hoeneisen B.; Hohlfeld M.; Hubacek Z.; Hynek V.; Iashvili I.; Ilchenko Y.; Illingworth R.; Ito A. S.; Jabeen S.; Jaffre M.; Jaminn D.; Jayasinghe A.; Jesik R.; Johns K.; Johnson M.; Jonckheere A.; Jonsson P.; Joshi J.; Jung A. W.; Juste A.; Kaadze K.; Kajfasz E.; Karmanov D.; Kasper P. A.; Katsanos I.; Kehoe R.; Kermiche S.; Khalatyan N.; Khanov A.; Kharchilava A.; Kharzheev Y. N.; Kohli J. M.; Kozelov A. V.; Kraus J.; Kulikov S.; Kumar A.; Kupco A.; Kurca T.; Kuzmin V. A.; Lammers S.; Landsberg G.; Lebrun P.; Lee H. S.; Lee S. W.; Lee W. M.; Lellouch J.; Li H.; Li L.; Li Q. Z.; Lietti S. M.; Lim J. K.; Lincoln D.; Linnemann J.; Lipaev V. V.; Lipton R.; Liu Y.; Lobodenko A.; Lokajicek M.; Lopes de Sa R.; Lubatti H. J.; Luna-Garcia R.; Lyon A. L.; Maciel A. K. A.; Mackin D.; Madar R.; Magana-Villalba R.; Malik S.; Malyshev V. L.; Maravin Y.; Martinez-Ortega J.; McCarthy R.; McGivern C. L.; Meijer M. M.; Melnitchouk A.; Menezes D.; Mercadante P. G.; Merkin M.; et al.
2012-04-20
We report results from searches for neutral Higgs bosons produced in p{bar p} collisions recorded by the D0 experiment at the Fermilab Tevatron Collider. We study the production of inclusive neutral Higgs boson in the {tau}{tau} final state and in association with a b quark in the b{tau}{tau} and bbb final states. These results are combined to improve the sensitivity to the production of neutral Higgs bosons in the context of the minimal supersymmetric standard model (MSSM). The data are found to be consistent with expectation from background processes. Upper limits on MSSM Higgs boson production are set for Higgs boson masses ranging from 90 to 300 GeV. We exclude tan {beta} > 20-30 for Higgs boson masses below 180 GeV. These are the most stringent constraints on MSSM Higgs boson production in p{bar p} collisions.
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, Michael; Doria, A; Dova, M T; Duchesneau, D; Echenard, B; Eline, A; El-Mamouni, H; Engler, A; Eppling, F J; Ewers, A; Extermann, Pierre; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, Marta; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Guida, M; van Gulik, R; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hakobyan, R S; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Käfer, D; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kräber, M H; Krämer, R W; Krenz, 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 A; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Lübelsmeyer, K; Luci, C; Luminari, L; Lustermann, W; Ma Wen Gan; Malgeri, L; Malinin, A; Maña, C; Mangeol, D J J; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Niessen, T; Nisati, A; Nowak, H; Ofierzynski, R A; Organtini, G; Palomares, C; Pandoulas, D; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofiev, D O; Prokofev, D; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P A; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosier-Lees, S; Roth, S; Rosenbleck, C; Roux, B; Rubio, Juan Antonio; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Sanders, M P; Schäfer, C; Shchegelskii, V; Schmidt-Kärst, S; Schmitz, D; Schopper, Herwig Franz; Schotanus, D J; Schwering, G; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A V; Siedenburg, T; 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 V; 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 P; 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; Wallraff, W; 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
2002-01-01
A search for the lightest neutral CP-even and neutral CP-odd Higgs bosons of the Minimal Supersymmetric Standard Model is performed using 216.6 pb-1 of data collected with the L3 detector at LEP at centre-of-mass energies between 203 and 209 GeV. No indication of a signal is found. Including our results from lower centre-of-mass energies, lower limits on the Higgs boson masses are set as a function of tan(beta) for several scenarios. For tan(beta) greater than 0.7 they are mh > 84.5 GeV and mA > 86.3 GeV at 95% confidence level.
Perturbative stability along the supersymmetric directions of the landscape
Sousa, Kepa [Department of Theoretical Physics and History of Science, University of the Basque Country UPV/EHU, 48080 Bilbao (Spain); Ortiz, Pablo, E-mail: kepa.sousa@ehu.es, E-mail: ortiz@lorentz.leidenuniv.nl [Instituut-Lorentz for Theoretical Physics, Universiteit Leiden, Niels Bohrweg 2, 2333 CA Leiden (Netherlands)
2015-02-01
We consider the perturbative stability of non-supersymmetric configurations in N=1 supergravity models with a spectator sector not involved in supersymmetry breaking. Motivated by the supergravity description of complex structure moduli in Large Volume Compactifications of type IIB-superstrings, we concentrate on models where the interactions are consistent with the supersymmetric truncation of the spectator fields, and we describe their couplings by a random ensemble of generic supergravity theories. We characterise the mass spectrum of the spectator fields in terms of the statistical parameters of the ensemble and the geometry of the scalar manifold. Our results show that the non-generic couplings between the spectator and the supersymmetry breaking sectors can stabilise all the tachyons which typically appear in the spectator sector before including the supersymmetry breaking effects, and we find large regions of the parameter space where the supersymmetric sector remains stable with probability close to one. We discuss these results about the stability of the supersymmetric sector in two physically relevant situations: non-supersymmetric Minkowski vacua, and slow-roll inflation driven by the supersymmetry breaking sector. For the class of models we consider, we have reproduced the regimes in which the KKLT and Large Volume Scenarios stabilise all supersymmetric moduli. We have also identified a new regime in which the supersymmetric sector is stabilised at a very robust type of dS minimum without invoking a large mass hierarchy.
Aaltonen, T; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Beauchemin, P H; Bedeschi, F; Behari, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bölla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, Yu; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carillo, S; Carlsmith, D; Carosi, R; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Cilijak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cuenca-Almenar, C; Cuevas-Maestro, J; Culbertson, R; Cully, J C; Da Ronco, S; Datta, M; D'Auria, S; Davies, T; Dagenhart, D; De Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; De Lorenzo, G; Dell'Orso, Mauro; Delli Paoli, F; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Dorr, C; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernández, J P; Field, R; Flanagan, G; Forrest, R; Forrester, S; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; García, J E; Garberson, F; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D; Giagu, S; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Golossanov, A; Gómez, G; Gómez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Group, R C; Grundler, U; Guimarães da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Hays, C; Heck, M; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hidas, D; Hill, C S; Hirschbuehl, D; Höcker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jeon, E J; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kraan, A C; Kraus, J; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kulkarni, N P; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lu, R S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Mäki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis, A; Margaroli, F; Marginean, R; Marino, C; Marino, C P; Martin, A; Martin, M; Martin, V; Martínez, M; Martinez-Ballarin, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtälä, P; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyamoto, A; Moed, S; Moggi, N; Mohr, B; Moon, C S; Moore, R; Morello, M; Movilla-Fernández, P A; Mülmenstädt, J; Mukherjee, A; Müller, T; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nodulman, L; Norniella, O; Nurse, E; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Oldeman, R; Orava, R; Österberg, K; Pagliarone, C; Palencia, E; Papadimitriou, V; Papaikonomou, A; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, Aldo L; Phillips, T J; Piacentino, G; Piedra, J; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Portell, X; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Reisert, B; Rekovic, V; Renton, P B; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Roy, P; Ruiz, A; Russ, J; Rusu, V; Saarikko, H; Safonov, A; Sakumoto, W K; Salamanna, G; Salto, O; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savard, P; Savoy-Navarro, A; Scheidle, T; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scott, A L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sfyrla, A; Shalhout, S Z; Shapiro, M D; Shears, T G; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakian, A; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Söderberg, M; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spinella, F; Spreitzer, T; Squillacioti, P; Stanitzki, M; Staveris-Polykalas, A; Saint-Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Stuart, D; Suh, J S; Sukhanov, A; Sun, H; Suslov, I; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tsuno, S; Tu, Y; Turini, N; Ukegawa, F; Uozumi, S; Vallecorsa, S; Van Remortel, N; Varganov, A; Vataga, E; Vázquez, F; Velev, G; Vellidis, C; Veramendi, G; Veszpremi, V; Vidal, M; Vidal, R; Vila, I; Vilar, R; Vine, T; Vogel, M; Vollrath, I; Volobuev, I; Volpi, G; Würthwein, F; Wagner, P; Wagner, R G; Wagner, R L; Wagner, J; Wagner, W; Wallny, R; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Wynne, S M; Yagil, A; Yamamoto, K; Yamaoka, J; Yamashita, T; Yang, C; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zhang, X; Zhou, J; Zucchelli, S
2007-01-01
We search for direct pair production of supersymmetric top quarks and supersymmetric bottom quarks in proton-antiproton collisions at $\\sqrt{s}$ = 1.96 TeV, using 295 pb^-1 of data recorded by the Collider Detector at Fermilab (CDF II) experiment. The supersymmetric top (supersymmetric bottom) quarks are selected by reconstructing their decay into a charm (bottom) quark and a neutralino, which is assumed to be the lightest supersymmetric particle. The signature of such processes is two energetic heavy-flavor jets and missing transverse energy. The number of events that pass our selection for each search process is consistent with the standard model expectation. By comparing our results to the theoretical production cross sections of the supersymmetric top and supersymmetric bottom quarks in the minimal supersymmetric standard model, we exclude, at a 95% confidence level in the frame of that model, a supersymmetric top quark mass up to 132 GeV/c^2 for a neutralino mass of 48 GeV/c^2, and a supersymmetric botto...
Supersymmetric unification at the millennium
Charanjit S Aulakh
2000-07-01
We argue that the discovery of neutrino mass effects at super-Kamiokande implies a clear logical chain leading from the Standard Model, through the MSSM and the recently developed minimal left right supersymmetric models with a renormalizable see-saw mechanism for neutrino mass, to left right symmetric SUSY GUTS: in particular, SO(10) and SU(2)× SU(2) × SU(4). The progress in constructing such GUTS explicitly is reviewed and their testability/falsiﬁability by lepton ﬂavour violation and proton decay measurements emphasized. SUSY violations of the survival principle and the interplay between third generation Yukawa coupling uniﬁcation and the structurally stable IR attractive features of the RG ﬂow in SUSY GUTS are also discussed.
Nonlocal quantum field theory without acausality and nonunitarity at quantum level: SUSY is the key
Addazi, Andrea
2015-01-01
The realization of a nonlocal quantum field theory without losing unitarity, gauge invariance and causality is investigated. It is commonly retained that such a formulation is possible at tree level, but at quantum level acausality reappears at one loop. We suggest the the problem of acausality is, in a broad sense, similar to the one about anomalies in quantum field theory. By virtue of this analogy, we suggest that acausal diagrams resulting from the fermionic sector and the bosonic one might cancel each other, with a suitable content of fields and suitable symmetries. As a simple example, we show how supersymmetry can alleviate this problem in a simple and elegant way, i.e., by leading to exact cancellations of harmful diagrams, to all orders of perturbation theory, in the case of a nonlocal Wess-Zumino model. On the other hand, the same is true for a super Yang-Mills model, but in this case, other important acausal diagrams are also originating from supersymmetric D-terms. As a consequence, we conjecture ...
Dispersion relations in quantum electrodynamics on the noncommutative Minkowski space
Zahn, J.W.
2006-12-15
We study field theories on the noncommutative Minkowski space with noncommuting time. The focus lies on dispersion relations in quantized interacting models in the Yang-Feldman formalism. In particular, we compute the two-point correlation function of the field strength in noncommutative quantum electrodynamics to second order. At this, we take into account the covariant coordinates that allow the construction of local gauge invariant quantities (observables). It turns out that this does not remove the well-known severe infrared problem, as one might have hoped. Instead, things become worse, since nonlocal divergences appear. We also show that these cancel in a supersymmetric version of the theory if the covariant coordinates are adjusted accordingly. Furthermore, we study the {phi}{sup 3} and the Wess-Zumino model and show that the distortion of the dispersion relations is moderate for parameters typical for the Higgs field. We also discuss the formulation of gauge theories on noncommutative spaces and study classical electrodynamics on the noncommutative Minkowski space using covariant coordinates. In particular, we compute the change of the speed of light due to nonlinear effects in the presence of a background field. Finally, we examine the so-called twist approach to quantum field theory on the noncommutative Minkowski space and point out some conceptual problems of this approach. (orig.)
Quantum dynamics of a bulk-boundary system
Ichinose, Shoichi; Murayama, Akihiro
2005-03-01
The quantum dynamics of a bulk-boundary theory is closely examined by the use of the background field method. As an example we take the Mirabelli-Peskin model, which is composed of 5D super-Yang-Mills (bulk) and 4D Wess-Zumino (boundary). Singular interaction terms play an important role of canceling the divergences coming from the KK-mode sum. Some new regularization of the momentum integral is proposed. An interesting background configuration of scalar fields is found. It is a localized solution of the field equation. In this process of the vacuum search, we present a new treatment of the vacuum with respect to the extra coordinate. The "supersymmetric" effective potential is obtained at the 1-loop full (w.r.t. the coupling) level. This is the bulk-boundary generalization of the Coleman-Weinberg's case. Renormalization group analysis is done and the correct 4D result is reproduced. The Casimir energy is calculated and is compared with the case of the Kaluza-Klein model.
Prolongation structures for supersymmetric equations
Roelofs, G.H.M.; Hijligenberg, van den N.W.
1990-01-01
The well known prolongation technique of Wahlquist and Estabrook (1975) for nonlinear evolution equations is generalized for supersymmetric equations and applied to the supersymmetric extension of the KdV equation of Manin-Radul. Using the theory of Kac-Moody Lie superalgebras, the explicit form of
Small numbers in supersymmetric theories of nature
Graesser, Michael Lawrence [Univ. of California, Berkeley, CA (United States)
1999-05-01
The Standard Model of particle interactions is a successful theory for describing the interactions of quarks, leptons and gauge bosons at microscopic distance scales. Despite these successes, the theory contains many unsatisfactory features. The origin of particle masses is a central mystery that has eluded experimental elucidation. In the Standard Model the known particles obtain their mass from the condensate of the so-called Higgs particle. Quantum corrections to the Higgs mass require an unnatural fine tuning in the Higgs mass of one part in 10^{-32} to obtain the correct mass scale of electroweak physics. In addition, the origin of the vast hierarchy between the mass scales of the electroweak and quantum gravity physics is not explained in the current theory. Supersymmetric extensions to the Standard Model are not plagued by this fine tuning issue and may therefore be relevant in Nature. In the minimal supersymmetric Standard Model there is also a natural explanation for electroweak symmetry breaking. Supersymmetric Grand Unified Theories also correctly predict a parameter of the Standard Model. This provides non-trivial indirect evidence for these theories. The most general supersymmetric extension to the Standard Model however, is excluded by many physical processes, such as rare flavor changing processes, and the non-observation of the instability of the proton. These processes provide important information about the possible structure such a theory. In particular, certain parameters in this theory must be rather small. A physics explanation for why this is the case would be desirable. It is striking that the gauge couplings of the Standard Model unify if there is supersymmetry close to the weak scale. This suggests that at high energies Nature is described by a supersymmetric Grand Unified Theory. But the mass scale of unification must be introduced into the theory since it does not coincide with the probable mass scale of strong quantum gravity
Aspects of a supersymmetric Brans-Dicke theory
Catena, R.
2006-11-15
We consider a locally supersymmetric theory where the Planck mass is replaced by a dynamical superfield. This model can be thought of as the Minimal Supersymmetric extension of the Brans-Dicke theory (MSBD). The motivation that underlies this analysis is the research of possible connections between Dark Energy models based on Brans-Dicke-like theories and supersymmetric Dark Matter scenarios. We find that the phenomenology associated with the MSBD model is very different compared to the one of the original Brans-Dicke theory: the new scalar and fermionic degrees of freedom do not couple to matter in a universal metric way, i.e. they can not be removed from the matter sector by a Weyl rescaling of the metric. This feature could make the minimal supersymmetric extension of the BD idea phenomenologically inconsistent. (orig.)
The supersymmetric flavor problem
Dimopoulos, Savas K; Dimopoulos, Savas; Sutter, Dave
1995-01-01
The supersymmetric SU(3)\\times SU(2)\\times U(1) theory with minimal particle content and general soft supersymmetry breaking terms has 110 physical parameters in its flavor sector: 30 masses, 39 real mixing angles and 41 phases. The absence of an experimental indication for the plethora of new parameters places severe constraints on theories posessing Planck or GUT-mass particles and suggests that theories of flavor conflict with naturalness. We illustrate the problem by studying the processes \\mu \\rightarrow e + \\gamma and K^0 - \\bar{K}^0 mixing which are very sensitive probes of Planckian physics: a single Planck mass particle coupled to the electron or the muon with a Yukawa coupling comparable to the gauge coupling typically leads to a rate for \\mu \\rightarrow e + \\gamma exceeding the present experimental limits. A possible solution is that the messengers which transmit supersymmetry breaking to the ordinary particles are much lighter than M_{\\rm Planck}.
Supersymmetric mode converters
Heinrich, Matthias; Miri, Mohammad-Ali; Stützer, Simon; Nolte, Stefan; Szameit, Alexander; Christodoulides, Demetrios N.
2015-08-01
In recent years, the ever-increasing demand for high-capacity transmission systems has driven remarkable advances in technologies that encode information on an optical signal. Mode-division multiplexing makes use of individual modes supported by an optical waveguide as mutually orthogonal channels. The key requirement in this approach is the capability to selectively populate and extract specific modes. Optical supersymmetry (SUSY) has recently been proposed as a particularly elegant way to resolve this design challenge in a manner that is inherently scalable, and at the same time maintains compatibility with existing multiplexing strategies. Supersymmetric partners of multimode waveguides are characterized by the fact that they share all of their effective indices with the original waveguide. The crucial exception is the fundamental mode, which is absent from the spectrum of the partner waveguide. Here, we demonstrate experimentally how this global phase-matching property can be exploited for efficient mode conversion. Multimode structures and their superpartners are experimentally realized in coupled networks of femtosecond laser-written waveguides, and the corresponding light dynamics are directly observed by means of fluorescence microscopy. We show that SUSY transformations can readily facilitate the removal of the fundamental mode from multimode optical structures. In turn, hierarchical sequences of such SUSY partners naturally implement the conversion between modes of adjacent order. Our experiments illustrate just one of the many possibilities of how SUSY may serve as a building block for integrated mode-division multiplexing arrangements. Supersymmetric notions may enrich and expand integrated photonics by versatile optical components and desirable, yet previously unattainable, functionalities.
Neutralino annihilation into massive quarks with supersymmetric QCD corrections
Herrmann, Björn; Klasen, Michael; Kovařík, Karol
2009-03-01
We compute the full O(αs) supersymmetric (SUSY)-QCD corrections for neutralino annihilation into massive quarks through gauge or Higgs bosons and squarks in the minimal supersymmetric standard model, including the known resummation of logarithmically enhanced terms. The numerical impact of the corrections on the extraction of SUSY mass parameters from cosmological data is analyzed for gravity-mediated SUSY-breaking scenarios and shown to be sizable, so that these corrections must be included in common analysis tools.
Liu, Chien-Hao
2016-01-01
In earlier works, D(1) (arXiv:0709.1515 [math.AG]), D(11.1) (arXiv:1406.0929 [math.DG]), D(11.2) (arXiv:1412.0771 [hep-th]), and D(11.3.1) (arXiv:1508.02347 [math.DG]), we have explained why a D-brane in string theory, when treated as a fundamental dynamical object, can be described by a map $\\varphi$ from an Azumaya/matrix manifold $X^{Az}$ (cf. D-brane world-volume) with a fundamental module with a connection $(E,\
Measuring And Explaining The Supersymmetric Lagrangian
Wang, L
2002-01-01
The issues of measuring the supersymmetric Lagrangian once data is available, and making the connections between the low energy effective Lagrangian and fundamental theory, are considered. After a brief introduction to the fundamentals of supersymmetry and overview of Minimal Supersymmetric Standard Model (MSSM), case studies in ways of measuring different parameters in the low energy MSSM Lagrangian are presented. They include: measuring CP violation phases and LSP masses in gluino decay; Higgs production and detection; flavor and CP violation in b → sγ processes; signature of cold dark matter in the cosmic rays. Potential ambiguities in the process of recovering the high energy effective Lagrangian from low energy data are discussed. A new basis, which is explicitly independent of unphysical parameters, is proposed to write the renormalization group equations. After a brief survey of some basic issues of string theory phenomenology, a string theory motivated Pati-Salam like model is const...
Selecting Supersymmetric String Scenarios From Sparticle Spectra
Allanach, Benjamin C; Quevedo, Fernando
2002-01-01
We approach the following question: if supersymmetry is discovered, how can we select among different supersymmetric extensions of the Standard Model? In particular, we perform an analysis of the sparticle spectrum in low-energy string effective theories, asking which observables best distinguish various scenarios. We examine scenarios differing by the fundamental string scale and concentrate on GUT and intermediate scale models. We scan over all parameters (two goldstino angles, tan beta and the gravitino mass) in each scenario, finding ratios of sparticle masses that provide the maximum discrimination between them. The necessary accuracy for discrimination is determined in each case. We find that the required accuracy on various sparticle mass ratios is at the few percent level, a precision that may be achieved in future linear colliders. We place phenomenological constraints on the parameter space and determine the supersymmetric contribution to the muon anomalous magnetic moment.
Jafarizadeh, M A; Fouladi, N; Ranjbar, Z; Sadighzadeh, A
2016-01-01
Solvable supersymmetric algebraic model for descriptions of the spherical to gama unstable shape- phase transition in even and odd mass nuclei is proposed. This model is based on dual algebraic structure and Richardson - Gaudin method, where the duality relations between the unitary and quasispin algebraic structures for the boson and fermion systems are extended to mixed boson- fermion system. The structure of two type of nuclear supersymmetry schemes, based on the U(6/2) and U(6/4) supergroups, is discussed. We investigate the change in level structure induced by the phase transition by doing a quantal analysis. By using the generalized quasispin algebra, it is shown that the nuclear supersymmetry concept can be also used for transitional regions in addition to dynamical symmetry limits. Experimental evidence for the U(5)-O(6) transition in Ru-Rh and Zn- Cu supermultiplets is presented. The low-states energy spectra and B(E2)values for these nuclei have been calculated and compared with the experimental dat...
Karagiannakis, N; Pallis, C
2015-01-01
We analyze the parametric space of the constrained minimal supersymmetric standard model with mu>0 supplemented by a generalized asymptotic Yukawa coupling quasi-unification condition which yields acceptable masses for the fermions of the third family. We impose constraints from the cold dark matter abundance in the universe and its direct detection experiments, the B-physics, as well as the masses of the sparticles and the lightest neutral CP-even Higgs boson. Fixing the mass of the latter to its central value from the LHC and taking 40<=tanbeta<=50, we find a relatively wide allowed parameter space with -11<=A_0/M_{1/2}<=15 and mass of the lightest sparticle in the range (0.09-1.1) TeV. This sparticle is possibly detectable by the present cold dark matter direct search experiments. The required fine-tuning for the electroweak symmetry breaking is much milder than the one needed in the neutralino-stau coannihilation region of the same model.
Supersymmetric quantum mechanics and paraquantization
Morchedi, O.; Mebarki, N. [Laboratoire de Physique Mathematique et Subatomique, Mentouri University, Constantine (Algeria)
2012-06-27
The paraquantum Hamiltonian of a free particle is shown to be supersymmetric. Depending on the space-time dimension, the corresponding N=1 and N=2 supercharges are constructed and the related Hamiltonians are derived.
Toivanen, P.; Kortelainen, M.; Suhonen, J.; Toivanen, J.
2009-04-01
We discuss the dark-matter detection rates for the elastic and inelastic scattering of the lightest supersymmetric particle (LSP) off nuclei. For this we use an easily accessible formalism where the underlying nuclear physics is condensed in structure coefficients multiplying the key parameters of supersymmetric theories. In this work we compute these coefficients for the stable iodine, xenon, and cesium nuclei by application of the nuclear shell model in a model space involving the 2s, 1d, 0g7/2, and 0h11/2 single-particle orbitals. As an interaction we use the renormalized Bonn-CD G matrix. By using fitted nuclear gyromagnetic factors we have successfully reproduced the relevant spectroscopic data on magnetic moments and M1 decays in the discussed nuclei.
Likelihood Analysis of Supersymmetric SU(5) GUTs
Bagnaschi, E. [DESY; Costa, J. C. [Imperial Coll., London; Sakurai, K. [Warsaw U.; Borsato, M. [Santiago de Compostela U.; Buchmueller, O. [Imperial Coll., London; Cavanaugh, R. [Illinois U., Chicago; Chobanova, V. [Santiago de Compostela U.; Citron, M. [Imperial Coll., London; De Roeck, A. [Antwerp U.; Dolan, M. J. [Melbourne U.; Ellis, J. R. [King' s Coll. London; Flächer, H. [Bristol U.; Heinemeyer, S. [Madrid, IFT; Isidori, G. [Zurich U.; Lucio, M. [Santiago de Compostela U.; Martínez Santos, D. [Santiago de Compostela U.; Olive, K. A. [Minnesota U., Theor. Phys. Inst.; Richards, A. [Imperial Coll., London; de Vries, K. J. [Imperial Coll., London; Weiglein, G. [DESY
2016-10-31
We perform a likelihood analysis of the constraints from accelerator experiments and astrophysical observations on supersymmetric (SUSY) models with SU(5) boundary conditions on soft SUSY-breaking parameters at the GUT scale. The parameter space of the models studied has 7 parameters: a universal gaugino mass $m_{1/2}$, distinct masses for the scalar partners of matter fermions in five- and ten-dimensional representations of SU(5), $m_5$ and $m_{10}$, and for the $\\mathbf{5}$ and $\\mathbf{\\bar 5}$ Higgs representations $m_{H_u}$ and $m_{H_d}$, a universal trilinear soft SUSY-breaking parameter $A_0$, and the ratio of Higgs vevs $\\tan \\beta$. In addition to previous constraints from direct sparticle searches, low-energy and flavour observables, we incorporate constraints based on preliminary results from 13 TeV LHC searches for jets + MET events and long-lived particles, as well as the latest PandaX-II and LUX searches for direct Dark Matter detection. In addition to previously-identified mechanisms for bringing the supersymmetric relic density into the range allowed by cosmology, we identify a novel ${\\tilde u_R}/{\\tilde c_R} - \\tilde{\\chi}^0_1$ coannihilation mechanism that appears in the supersymmetric SU(5) GUT model and discuss the role of ${\\tilde \
Supersymmetric quantum mechanics with reflections
Post, Sarah; Vinet, Luc [Centre de Recherches Mathematiques, Universite de Montreal, Montreal CP6128 (QC) H3C 3J7 (Canada); Zhedanov, Alexei, E-mail: post@crm.umontreal.ca, E-mail: luc.vinet@umontreal.ca, E-mail: zhedanov@fti.dn.ua [Donetsk Institute for Physics and Technology, Donetsk 83114 (Ukraine)
2011-10-28
We consider a realization of supersymmetric quantum mechanics where supercharges are differential-difference operators with reflections. A supersymmetric system with an extended Scarf I potential is presented and analyzed. Its eigenfunctions are given in terms of little -1 Jacobi polynomials which obey an eigenvalue equation of Dunkl type and arise as a q {yields} -1 limit of the little q-Jacobi polynomials. Intertwining operators connecting the wavefunctions of extended Scarf I potentials with different parameters are presented. (paper)
A supersymmetric consistent truncation for conifold solutions
Cassani, Davide
2010-01-01
We establish a supersymmetric consistent truncation of type IIB supergravity on the T^{1,1} coset space, based on extending the Papadopoulos-Tseytlin ansatz to the full set of SU(2)xSU(2) invariant Kaluza-Klein modes. The five-dimensional model is a gauged N=4 supergravity with three vector multiplets, which incorporates various conifold solutions and is suitable for the study of their dynamics. By analysing the scalar potential we find a family of new non-supersymmetric AdS_5 extrema interpolating between a solution obtained long ago by Romans and a solution employing an Einstein metric on T^{1,1} different from the standard one. Finally, we discuss some simple consistent subtruncations preserving N=2 supersymmetry. One of them is compatible with the inclusion of smeared D7-branes.
The gravitino problem in supersymmetric warm inflation
Sanchez, Juan C Bueno; Berera, Arjun; Dimopoulos, Konstantinos; Kohri, Kazunori
2010-01-01
The warm inflation paradigm considers the continuous production of radiation during inflation due to dissipative effects. In its strong dissipation limit, warm inflation gives way to a radiation dominated Universe. High scale inflation then yields a high reheating temperature, which then poses a severe gravitino overproduction problem for the supersymmetric realisations of warm inflation. In this paper we show that in certain class of supersymmetric models the dissipative dynamics of the inflaton is such that the field can avoid its complete decay after inflation. In some cases, the residual energy density stored in the field oscillations may come to dominate over the radiation bath at a later epoch. If the inflaton field finally decays much later than the onset of the matter dominated phase, the entropy produced in its decay may be sufficient to counteract the excess of gravitinos produced during the last stages of warm inflation.
Aad, Georges; Abbott, Brad; Abdallah, Jalal; Abdel Khalek, Samah; Abdelalim, Ahmed Ali; Abdinov, Ovsat; Aben, Rosemarie; Abi, Babak; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina; Abreu, Henso; Acharya, Bobby Samir; Adamczyk, Leszek; Adams, David; Addy, Tetteh; Adelman, Jahred; Adomeit, Stefanie; Adragna, Paolo; Adye, Tim; Aefsky, Scott; Aguilar-Saavedra, Juan Antonio; Agustoni, Marco; Ahlen, Steven; Ahles, Florian; Ahmad, Ashfaq; Ahsan, Mahsana; Aielli, Giulio; Åkesson, Torsten Paul Ake; Akimoto, Ginga; Akimov, Andrei; Alam, Muhammad Aftab; Albert, Justin; Albrand, Solveig; Aleksa, Martin; Aleksandrov, Igor; Alessandria, Franco; Alexa, Calin; Alexander, Gideon; Alexandre, Gauthier; Alexopoulos, Theodoros; Alhroob, Muhammad; Aliev, Malik; Alimonti, Gianluca; Alison, John; Allbrooke, Benedict; Allison, Lee John; Allport, Phillip; Allwood-Spiers, Sarah; Almond, John; Aloisio, Alberto; Alon, Raz; Alonso, Alejandro; Alonso, Francisco; Altheimer, Andrew David; Alvarez Gonzalez, Barbara; Alviggi, Mariagrazia; Amako, Katsuya; Amelung, Christoph; Ammosov, Vladimir; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amram, Nir; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Andrieux, Marie-Laure; Anduaga, Xabier; Angelidakis, Stylianos; Anger, Philipp; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antonaki, Ariadni; Antonelli, Mario; Antonov, Alexey; Antos, Jaroslav; Anulli, Fabio; Aoki, Masato; Aoun, Sahar; Aperio Bella, Ludovica; Apolle, Rudi; Arabidze, Giorgi; Aracena, Ignacio; Arai, Yasuo; Arce, Ayana; Arfaoui, Samir; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Engin; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnal, Vanessa; Artamonov, Andrei; Artoni, Giacomo; Arutinov, David; Asai, Shoji; Ask, Stefan; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astbury, Alan; Atkinson, Markus; Aubert, Bernard; Auge, Etienne; Augsten, Kamil; Aurousseau, Mathieu; Avolio, Giuseppe; Axen, David; Azuelos, Georges; Azuma, Yuya; Baak, Max; Baccaglioni, Giuseppe; Bacci, Cesare; Bach, Andre; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Backus Mayes, John; Badescu, Elisabeta; Bagnaia, Paolo; Bai, Yu; Bailey, David; Bain, Travis; Baines, John; Baker, Oliver Keith; Baker, Sarah; Balek, Petr; Banas, Elzbieta; Banerjee, Piyali; Banerjee, Swagato; Banfi, Danilo; Bangert, Andrea Michelle; Bansal, Vikas; Bansil, Hardeep Singh; Barak, Liron; Baranov, Sergei; Barber, Tom; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Bardin, Dmitri; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnett, Bruce; Barnett, Michael; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartsch, Valeria; Basye, Austin; Bates, Richard; Batkova, Lucia; Batley, Richard; Battaglia, Andreas; Battistin, Michele; Bauer, Florian; Bawa, Harinder Singh; Beale, Steven; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Bechtle, Philip; Beck, Hans Peter; Becker, Anne Kathrin; Becker, Sebastian; Beckingham, Matthew; Becks, Karl-Heinz; Beddall, Andrew; Beddall, Ayda; Bedikian, Sourpouhi; Bednyakov, Vadim; Bee, Christopher; Beemster, Lars; Begel, Michael; Behar Harpaz, Silvia; Behera, Prafulla; Beimforde, Michael; Belanger-Champagne, Camille; Bell, Paul; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellomo, Massimiliano; Belloni, Alberto; Beloborodova, Olga; Belotskiy, Konstantin; Beltramello, Olga; Benary, Odette; Benchekroun, Driss; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez Garcia, Jorge-Armando; Benjamin, Douglas; Benoit, Mathieu; Bensinger, James; Benslama, Kamal; Bentvelsen, Stan; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Berglund, Elina; Beringer, Jürg; Bernat, Pauline; Bernhard, Ralf; Bernius, Catrin; Berry, Tracey; Bertella, Claudia; Bertin, Antonio; Bertolucci, Federico; Besana, Maria Ilaria; Besjes, Geert-Jan; Besson, Nathalie; Bethke, Siegfried; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianchini, Louis; Bianco, Michele; Biebel, Otmar; Bieniek, Stephen Paul; Bierwagen, Katharina; Biesiada, Jed; Biglietti, Michela; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien; Bingul, Ahmet; Bini, Cesare; Biscarat, Catherine; Bittner, Bernhard; Black, Curtis; Black, Kevin; Blair, Robert; Blanchard, Jean-Baptiste
2013-01-01
A search for neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) is reported. The analysis is based on a sample of proton-proton collisions at a centre-of-mass energy of 7 TeV recorded with the ATLAS detector at the Large Hadron Collider. The data were recorded in 2011 and correspond to an integrated luminosity of 4.7 fb$^{-1}$ to 4.8 fb$^{-1}$. Higgs boson decays into oppositely-charged muon or tau lepton pairs are considered for final states requiring either the presence or absence of b-jets. No statistically significant excess over the expected background is observed and exclusion limits at the 95% confidence level are derived. The exclusion limits are for the production cross-section of a generic neutral Higgs boson, $\\phi$, as a function of the Higgs boson mass and for h/H/A production in the MSSM as a function of the parameters $m_A$ and $tan\\beta$ in the $m_h^{max}$ scenario for $m_A$ in the range of 90 GeV to 500 GeV.
Scopel, S; Fornengo, N; Bottino, A
2011-01-01
We discuss the impact for light neutralinos in an effective Minimal Supersymmetric extension of the Standard Model of the recent results presented by the CMS and ATLAS Collaborations at the CERN Large Hadron Collider for a search of supersymmetry in proton-proton collisions at a center-of-mass energy of 7 TeV with an integrated luminosity of 35 inverse pb. We find that, in the specific case of light neutralinos, efficiencies for the specific signature searched by ATLAS (jets+missing transverse energy and an isolated lepton) imply a lower sensitivity compared to CMS (which searches for jets +missing transverse energy). Focusing on the CMS bound, if squark soft masses of the three families are assumed to be degenerate, the combination of the ensuing constraint on squark and gluino masses with the experimental limit on the b to s + gamma decay imply a lower bound on the neutralino mass that can reach the value of 11.9 GeV, depending on the gluino mass. On the other hand, when the universality condition among squ...
Babu, K S; 10.1103/PhysRevD.68.035004
2003-01-01
The extended supersymmetric standard model (ESSM), motivated on several grounds, introduces two vectorlike families (16+16) of SO(10) with masses of the order of one TeV. It is noted that the successful predictions of prior work on fermion masses and mixings, based on the MSSM embedded in SO(10), can be retained rather simply within the ESSM extension. These include an understanding of the smallness of V /sub cb/ approximately=0.04 and the largeness of the nu /sub mu /- nu /sub tau / oscillation angle, sin/sup 2/2 theta /sub nu ( mu ) nu ( tau )//sup osc/ approximately=1. We analyze the new contributions arising through the exchange of the vectorlike families of the ESSM to radiative processes including tau to mu gamma , mu to e gamma , b to s gamma , the EDM of the muon and the muon (g-2). We show that the ESSM makes significant contributions especially to the decays tau to mu gamma and mu to e gamma and simultaneously to muon (g-2). For a large and plausible range of relevant parameters, we obtain a/sub mu ...
Caron, Sascha; Hendriks, Luc; de Austri, Roberto Ruiz; Weniger, Christoph
2015-01-01
Observations with the Fermi Large Area Telescope (LAT) indicate an excess in gamma rays originating from the center of our Galaxy. A possible explanation for this excess is the annihilation of Dark Matter particles. We have investigated the annihilation of neutralinos as Dark Matter candidates within the phenomenological Minimal Supersymmetric Standard Model (pMSSM). An iterative particle filter approach was used to search for solutions within the pMSSM. We found solutions that are consistent with astroparticle physics and collider experiments, and provide a reasonable fit to the energy spectrum of the excess. The neutralino is a Bino/Higgsino mixture and a mass in the range $84-92$~GeV yielding a Dark Matter relic density $0.06 < \\Omega h^2 <0.13$. These pMSSM solutions make clear forecasts for LHC, direct and indirect DM detection experiments. If the pMSSM explanation of the excess seen by Fermi-LAT is correct, a DM signal might be discovered soon.