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Comment on Z''s and the H1 and ZEUS High Q2 Anomalies ; We investigate the effects of extra neutral gauge bosons on the high Q2 region of the ep to e X cross section at sqrts300 GeV. We found that the only models with electroweak strength coupling, typical of extended gauge theories, that give a better fit to the H1 and ZEUS high Q2 data than the standard model, are ruled out by existing data from the Tevatron. From general scaling arguments, using the allowed contact interactions, the only allowed models with Z''s would be those with strong couplings although even in this case the statistical evidence is not compelling.

Determinations of Standard Model Parameters from Lattice QCD ; In this talk I review some recent results from lattice QCD calculations which aim to a more accurate determination of the Standard Model parameters in the quark sector. After a review of our current knowledge of these parameters, I present lattice results for the strange, charm and bottom quark masses, the CKM matrix element Vub and the complex CKM phase delta, which induces CP violation effects in the Standard Model with three generations.

A Simple Complete Model of GaugeMediated SUSYBreaking and Dynamical Relaxation Mechanism for Solving the muProblem ; In this paper two things are done. First, we propose a simple model of dynamical gaugemediated SUSY breaking. This model incorporates a dynamical relaxation mechanism which solves the muproblem with no light fields beyond those of the MSSM. In the second part of the paper we show how this mechanism is generalized and give two more examples in which it is incorporated.

A Possible Unification Model for All Basic Forces ; A unification model for strong, electromagnetic, weak and gravitational forces is proposed. The tangent space of ordinary coordinate 4dimensional spacetime is a submanifold of an 14dimensional internal spacetime spanned by four frame fields. The unification of the standard model with gravity is governed by gauge symmetry in the internal spacetime.

Constraining the scales of supersymmetric leftright models ; We'll review our study of the constraints on the scales in the supersymmetric leftright model SUSYLR. The conservation of color and electromagnetism in the ground state of the theory implies a relation between righthanded gauge boson mass and soft squark mass. Furthermore, in general for heavy WR, tanalpha is larger than one, and the righthanded sneutrino VEV, responsible for spontaneous Rparity breaking, is at most of the order MSUSYhDeltaR, where MSUSY is supersymmetry breaking scale and hDeltaR is the Yukawa coupling in Majorana mass term for righthanded neutrinos.

Model independent analysis of the trilinear gauge boson couplings at LC role of polarized cross sections ; By means of a modelindependent analysis, we discuss the constraints on anomalous trilinear gaugeboson couplings that can be obtained from the study of electronpositron annihilation into W pairs at LC with sqrts0.5 TeV and 1 TeV. We consider the general CP conserving anomalous effective Lagrangian, as well as some specific models with reduced number of independent couplings. The analysis is based on combinations of observables with initial and final state polarizations, that allow to separately constrain the different couplings and to improve the corresponding numerical bounds.

Radiative GUT Symmetry Breaking in a RSymmetric Flipped SU5 Model ; We study the generation of the GUT scale through radiative corrections in the context of a Rsymmetric flipped SU5 X U1X model. A negative mass squared term for the GUT Higgs fields develops due to radiative effects along a flat direction at a superheavy energy scale. The Rsymmetry is essential in maintaining tripletdoublet splitting and Fflatness in the presence of nonrenormalizable terms. The model displays radiative electroweak symmetry breaking and satisfies all relevant phenomenological constraints.

Spontaneous CP violation and Higgs spectrum in a Next to Minimal Supersymmetric Model ; We explore the possibility of spontaneous CP violation within the Next to Minimal Supersymmetric Standard Model. In the most general form of the model, without a discrete Z3 symmetry, we find that even at tree level spontaneous CP violation can occur, while also permitting Higgs masses consistent with experiment.

New String Excitations in the TwoHiggs Standard Model ; We establish the existence of a static, classically stable string solution in a region of parameters of the generic twoHiggs Standard Model. In an appropriate limit of parameters, the solution reduces to the wellknown soliton of the O3 nonlinear sigma model.

A New Model of TopcolorAssisted Technicolor ; I present a model of topcolorassisted technicolor that can have topcolor breaking of the desired pattern, hard masses for all quarks and leptons, mixing among the heavy and light generations, and explicit breaking of all technifermion chiral symmetries except electroweak SU2 otimes U1. These positive features depend on the outcome of vacuum alignment. The main flaw in this model is taulepton condensation.

Light active and sterile neutrinos from compositeness ; Neutrinos can have naturally small Dirac masses if the Standard Model singlet righthanded neutrinos are light composite fermions. Theories which produce light composite fermions typically generate many of them, three of which can marry the lefthanded neutrinos with small Dirac masses. The rest can serve as sterile states which can mix with the Standard Model neutrinos. We present explicit models illustrating this idea.

A Toy Model for Open Inflation ; The open inflation scenario based on the theory of bubble formation in the models of a single scalar field suffered from a fatal defect. In all the versions of this scenario known so far, the ColemanDe Luccia instantons describing the creation of an open universe did not exist. We propose a simple onefield model where the CDL instanton does exist and the open inflation scenario can be realized.

Vector Boson decays of the Higgs Boson ; We derive the width of the Higgs boson into vector bosons. General formulas are derived both for the onshell decay H VV as well for the offshell decays, H V V and H V V, where Vgamma,W,Z. For the offshell decays the width of the decaying vector boson is properly included. The formulas are valid both for the Standard Model as well as for arbitrary extensions. As an example we study in detail the gaugeinvariant effective Lagrangian models where we can have sizable enhancements over the Standard Model that could be observed at LEP.

A Color Mutation Hadronic Soft Interaction Model Eikonal Formalism and Branching Evolution ; ECOMB is established as a hadronic multiparticle production generator by soft interaction. It incorporates the eikonal formalism, parton model, color mutation, branching, resonance production and decay. A partonic cluster, being colorneutral initially, splits into smaller colorneutral clusters successively due to the color mutation of the quarks. The process stops at hadronic resonance, qbar q pair, formation. The model contains selfsimilar dynamics and exhibits scaling behavior in the factorial moments, e.g. the intermittency.

Neutrinos A Glimpse Beyond the Standard Model ; After a review of the early history of neutrinos and their detection, we analyze the different types of models that extend the standard model to massive neutrinos. We emphasize the generic nature of maximal mixing between muon and tau neutrinos, given simple assumptions based on grand unification.

A First Principles Warm Inflation Model that Solves the Cosmological HorizonFlatness Problems ; A quantum field theory warm inflation model is presented that solves the horizonflatness problems. The model obtains, from the elementary dynamics of particle physics, cosmological scale factor trajectories that begin in a radiation dominated regime, enter an inflationary regime and then smoothly exit back into a radiation dominated regime, with nonnegligible radiation throughout the evolution.

Baryogenesis in Models with a Low Quantum Gravity Scale ; We make generic remarks about baryogenesis in models where the scale Ms of quantum gravity is much below the Planck scale. These correspond to Mtheory vacua with a large volume for the internal space. Baryogenesis is a challenge, particularly for Ms lappeq 105 GeV, because there is an upper bound on the reheat temperature of the Universe, and because certain baryon number violating operators must be suppressed. We discuss these constraints for different values of Ms, and illustrate with a toy model the possibility of using horizontal family symmetries to circumvent them.

Strange quark matter with dynamically generated quark masses ; Bulk properties of strange quark matter SQM are investigated within the SU3 NambuJonaLasinio model. In the chiral limit the model behaves very similarly to the MIT bag model which is often used to describe SQM. However, when we introduce realistic current quark masses, the strange quark becomes strongly disfavored, because of its large dynamical mass. We conclude that SQM is not absolutely stable.

The GaugeHiggs System in Three Dimensions to Twoloop Order ; The 3dimensional gaugeHiggs system describes the nonperturbative infrared effects of the hightemperature phase of the Standard Model. We calculate the twoloop selfenergies in the 3dimensional SU2 Higgs model and in the corresponding gauged nonlinear sigmamodel. As an application of the results, we estimate the dynamically generated vector boson mass in the symmetric phase of the Higgs model by means of gap equations.

Standard Model LargeET Processes and Searches for New Physics at HERA ; Existing and missing calculations of standard model processes producing large transverse energy in electronproton interactions at HERA are reviewed. The adequacy of the existing standard model Monte Carlo programs for generic searches of exotic processes is analyzed.

Second Loop Corrections from Superheavy Gauge Sector to Gauge Coupling Unification ; We deal with extensions of the Standard Model by adding horizontal interactions between particle generations. We calculate two loop corrections caused by the presence of coupling between hypothetical horizontal gauge bosons and matter fields, both at low and high energy. It is proved numerically, that the coupling of such extra bosons does not affect the positive features of unified and extended standard models with horizontal symmetry discussed in former publications.

The bard baru asymmetry of the proton in a Pion Cloud Model approach ; We study the bard baru asymmetry of the proton in a model approach in which hadronic fluctuations of the nucleon are generated through gluon splitting and recombination mechanisms. Within this framework, it is shown that the ud asymmetry of the proton is consistently described by including only nucleon fluctuations to pi N and pi Delta bound states. Predictions of the model closely agree with the recent experimental data of the E866NuSea Collaboration.

Bimaximal Neutrino Mixing With SO3 Flavour Symmetry ; We demonstrate that an SU2Ltimes U1Y model with extended Higgs sector gives rise to bimaximal neutrino mixing through the incorporation of SO3 flavour symmetry and discrete symmetry. The neutrino and the charged lepton masses are generated due to higher dimensional terms. The hierarchical structures of neutrinos and charged leptons are obtained due to inclusion of SO3 flavour symmetry and discrete symmetry.The model can accommodate the vacuum oscillation solution of solar neutrino problem, through reasonable choice of model parameters along with the atmospheric neutrino experimental result.

Swave Scattering Lengths in the SU2 NJL Model Beyond Meanfield Approximation ; The Swave pi pi scattering lengths a0 and a2 are calculated to the lowest order of 1Nc expansion in the general framework of SU2 NJL model beyond meanfield approximation. It is shown that using the universal curve of a0 and a2 the four NJL parameters, i.e., the current quark mass m0, the four fermion coupling constant G, the quark momentum cutoff Lambdaf and the meson momentum cutoff Lambdab, also the Swave pi pi scattering lengths in NJL model can be uniquely determined.

A gaugemediated supersymmetry breaking model with an extra singlet Higgs field ; We study in some detail the nexttominimal supersymmetric standard model with gauge mediation of supersymmetry breaking. We find that it is feasible to spontaneously generate values of the Higgs mass parameters mu and Bmu consistent with radiative electroweak symmetry breaking. The model has a phenomenologically viable particle spectrum. Messenger sneutrinos with mass in the range 6 to 25 TeV can serve as cold dark matter. It is also possible to evade the cosmological domain wall problem in this scenario.

Transverse Momentum Transfer and Low x Parton Dynamics at HERA ; The transverse momentum transfer correlation is introduced as a sensitive probe that can be used to discriminate between models for parton dynamics in lowx deepinelastic scattering. Expectations for uncorrelated models and models with shortrange or longrange correlations are discussed and confronted to results obtained from the LEPTO and ARIADNE Monte Carlo simulations programmes.

A Global Study of PhotonInduced Jet Production ; We present results of a global tuning of general purpose Monte Carlo models to published measurements of photonproton jets at HERA and photonphoton jets at LEP and TRISTAN. The principle free parameters in the tuning are the simulation of the underlying event and the choice of photon structure. Several combinations of models are ruled out by the data. Some consequences of the tuned models at a future linear collider are discussed.

On the Construction of Quintessential Inflation Models ; Attention has been recently drawn towards models in which inflation and quintessence schemes are unified. In such quintessential inflation' models, a unique scalar field is required to play both the role of the inflaton and of the latetime dynamical cosmological constant. We address the issue of the initial conditions for quintessence in this context and find that, in the two explicit examples provided, inflation can uniquely fix them to be in the allowed range for a present day tracking.

Yukawa couplings and proton decay in SUSY models ; We discuss proton decay induced by dimension5 operators in supersymmetric models containing extra hypercharge13 colortriplets. We derive a general formula relating dimension5 operator to the colortriplet mass matrix. We show that certain zeros in the triplet massmatrix together with some triplet coupling selection rules can lead to elimination of dimension5 operators. We apply this mechanism to SU5 and flipped SU5 theories with extended Higgs sectors.

Electric charge, early universe and the Superstring Theories ; Very recently, it has been shown by the author that the Standard Model Higgs cannot be a physical particle. Here, on most general grounds it is established that as per the Standard Model there is no electric charge above the electroweak phase transition temperature. Hence there was no electric charge present in the early universe. The Superstring Theories are flawed in as much as they are incompatible with this requirement. Hence the Superstring Theories are inconsistent with this basic structure and requirement of the Standard Model.

Electroweak characteristics of mesons in the relativistic quark model ; In this work the electromagnetic radius and the polarizability of the mesons are obtained by use of the effective Lagrangians constructed on the one hand with taking into account of general principles of the relativistic quantum field theory and on the other hand with taking into account of the compound relativistic model meson representation. Also using a relativistic constituent quark model based on point form of Poincarecovariant quantum mechanics we calculated electromagnetic radius and the decay constants of the mesons with spinor quarks.

Models of Neutrino Mass and Mixing ; There are two basic theoretical approaches to obtaining neutrino mass and mixing. In the minimalist approach, one adds just enough new stuff to the Minimal Standard Model to get mnu neq 0 and Ualpha i neq 1. In the holistic approach, one uses a general framework or principle to enlarge the Minimal Standard Model such that, among other things, mnu neq 0 and Ualpha i neq 1. In both cases, there are important side effects besides neutrino oscillations. I discuss a number of examples, including the possibility of leptogenesis from R parity nonconservation in supersymmetry.

Quintessential Adjustment of the Cosmological Constant ; We construct a time dependent adjustment mechanism for the cosmological constant which could be at work in a late FriedmannRobertsonWalker universe dominated by quintessence and matter. It makes use of a BransDicke field that couples to the evolving standardmodel vacuum energy density. Our explicit model possesses a stable latetime solution with a fixed ratio of matter and field energy densities. No fine tuning of model parameters or initial conditions is required.

A BraneWorld Explanation of the KARMEN Anomaly ; Motivated by the anomaly in the KARMEN experiment, we study new possibilities for braneworld models of neutrino masses. We show that the KARMEN anomaly can be understood in the context of a sixdimensional braneworld model. The finetuning problem associated with the singleparticle interpretation of the anomaly is thereby alleviated. Our model shows some interesting properties of general interest for braneworld neutrino physics. In particular, the size of the branebulk mixing decouples from the scales relevant for atmospheric and solar neutrino oscillations.

StronglyInteracting Heavy Flavors Beyond the Standard Model ; The origin of mass must lie in physics beyond the Standard Model. Dynamical electroweak symmetry breaking models like technicolor can generate masses for the W and Z bosons. Providing the large top quark mass and large topbottom mass splitting while keeping rho parameter and flavorchanging neutral currents small requires new strong dynamics for the top and bottom quarks. In consequence, new particles are predicted at scales up to 10 TeV with signatures in jets or heavy flavors. Searches for these states are underway at Fermilab and LEP II.

Total Cross Sections with Virtual Photons ; A model for total cross sections with virtual photons is presented, in particular gammap and gammagamma cross sections are considered. Our approach is based on an existing model for photoproduction, which subdivides the total cross section into three distinct event classes direct, VMD and anomalous. In the region of large photon virtualities, the Deep Inelastic Scattering processes up to Oalphas corrections are obtained. Hence, the model provides a smooth transition between the two regions. By the breakdown into different event classes, a complete picture of all event properties is the ultimate goal.

SemiLeptonic B Meson Decays to Excited D Mesons in the Covariant Oscillator Quark Model ; The spectra and branching ratios of the weak semileptonic B meson decays to the first excited D mesons are predicted, taking into account the confined effects of quarks using the covariant oscillator quark model COQM. In the COQM the same relation between general weak transition form factors as that in HQET is derived, and the concrete form of the IsgurWise function is given with no free parameters. Our results are somewhat different from those of other models. The present experimental data are not sufficient for comparison.

New model for the neutrino mass matrix ; I suggest a model based on a softly broken symmetry Le Lmu Ltau and on Babu's mechanism for twoloops radiative generation of the neutrino masses. The model predicts that one of the physical neutrinos nu3 is massless and that its component along the nue direction Ue3 is zero. Moreover, if the softbreaking term is assumed to be very small, then the vacuum oscillations of nue have almost maximal amplitude and solve the solarneutrino problem. New scalars are predicted in the 10 TeV energy range, and a breakdown of emutau universality should not be far from existing experimental bounds.

The Neutron EDM in the SM A Review ; We review the status of the electric dipole moment EDM of neutron in the Standard Model SM. The contributions of the strong and electroweak interactions are discussed seperately. In each case the structure of the Lagrangian and the sources of CP violation are specified, and calculational details are given subsequently. These two contributions to the neutron EDM exist in any extension of the SM including supersymmetry, twodoublet models as well as models with more than three generations of fermions. We do not discuss the EDM in such extensions; however, we briefly summarize their predictions with a detailed account of the related literature.

A TwoDimensional Model with Chiral Condensates and Cooper Pairs Having QCDlike Phase Structure ; We describe how a generalization of the original GrossNeveu model from UN to ON flavor symmetry leads to the appearance of a pairing condensate at high density, in agreement with the conjectured phenomenon of color superconductivity in 31dimensional QCD. Moreover, the model displays a rich phase structure which closely resembles the one expected in twoflavor QCD.

New supersymmetric standard model with stable proton ; We discuss a supersymmetric extension of the standard model with an extra U1 gauge symmetry. In this model, the proton stability is guaranteed by the gauge symmetry without invoking R parity. The gauge symmetry breakdown automatically generates an effective mu term and large Majorana masses for righthanded neutrinos. The supersymmetrysoftbreaking terms for scalar fields could be universal at a very high energy scale, and the electroweak symmetry is broken through radiative corrections.

Neutrino Oscillation Scenarios and GUT Model Predictions ; The present experimental situation regarding neutrino oscillations is first summarized, followed by an overview of selected grand unified models which have been proposed to explain the various scenarios with three active neutrinos and their righthanded counterparts. Special attention is given to the general features of the models and their ability to favor some scenarios over others.

Neutrino Physics with Small Extra Dimensions ; We study neutrino physics in the context of the localized gravity model with nonfactorizable metric proposed by Randall and Sundrum. Identifying the righthanded neutrino with a bulk fermion zero mode, which can be localized on the hidden'' 3brane in the RandallSundrum model, we obtain naturally small Dirac neutrino masses without invoking a seesaw mechanism. Our model predicts a strong hierarchy of neutrino masses and generically large mixing angles.

Neutralino Proton Cross Sections in SUGRA and DBRANE Models ; We calculate the spin independent neutralinoproton cross section for universal SUGRA, non universal SUGRA and Dbrane models with Rparity invariance. The regions of maximum cross section in these models has started to be probed by the current detectors. The minimum cross section generally is 1times 10910pb and hence will be accessible in the future detectors, barring special regions of parameter space where it can reduce to 1012pb. However, the squarks and gluinos will be heavy 1 TeV in the latter case, but still accessible at the LHC.

The Standard Model Physical Basis and Scattering Experiments ; We present an introduction into the basic concepts of the Standard Model, i.e. the gauge theories of the forces and the Higgs mechanism for generating masses. The GlashowSalamWeinberg theory of the electroweak interactions will be described in detail. The key experiments are reviewed, including the precision tests at high energies. Finally, the limitations and possible physics areas beyond the Standard Model are discussed.

Unitarity constraints on scalar parameters of the Standard and Two Higgs Doublets Model ; Unitarity constraints on the scalar parameters both for the Standard Model and the general Two Higgs Doublet Model THDM are examined. In the case of the THDM with an exact discrete symmetry transformation, we show that the mass of the lightest CPeven Higgs boson Mh and tanbeta are strongly correlated and consequently a strong lower bound can be put on Mh for large tanbeta. It is also shown that the inclusion of the discrete symmetry breaking term relaxes the aforementioned correlation.

HadronHadron Interactions in the Constituent Quark Model Results and Extensions ; Hadronic interactions are discussed within the context of the constituent quark model. The Quark Born Diagram methodology is outlined, extensive applications to mesonmeson and mesonbaryon interactions are discussed, and general features of these interactions are highlighted. The second half of this document deals with shortcomings of the quark model approach and methods to overcome them. These include relativistic kinematics, unitarity, nonlocal potentials, coupled channel effects, and the chiral nature of the pion.

Comment on Infrared Fixed Point Structure in Minimal Supersymmetric Standard Model with Baryon and Lepton Number Violation ; 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 hepph0011274. 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.

Maximal Neutrino Mixing from an Attractive Infrared Fixed Point ; In the Standard Model and MSSM, renormalization effects on neutrino mixing are generally very small and the attractive fixed points are at vanishing neutrino mixing. However for multihiggs extensions of the Standard Model, renormalization effects on neutrino mixing can be large and nontrivial fixed points are possible. Here we examine a simple twohiggs model. For two flavors, maximal mixing is an attractive infrared fixed point. For three flavors, the neutrino mass matrix evolves towards large offdiagonal elements at low energies. The experimentally suggested bimaximal neutrino mixing pattern is one possible attractive infrared fixed point.

Generalization of the Dick Model ; We discuss a model with a massless scalar coupling to the YangMills SU2 gauge field in fourdimensional spacetime. The solutions from static, pointlike colour source are given. There exists not only solutions with finite energy but also singular one which describes confinement. The confining potential depends on the delta parameter of our model. The regular magnetic monopole solutions as well as the singular dyon configurations are also obtained. We fit the delta parameter to the experimental data.

Model independent constraints on contact interactions from polarized Bhabha scattering at LC ; We discuss electronelectron contactinteraction searches in the process ee ee at a future ee Linear Collider with c.m. energy sqrts0.5 TeV and with both beams longitudinally polarized. Our analysis is based on the measurement of the polarized differential cross sections, and allows to simultaneously take into account the general set of contact interaction couplings as independent, nonzero, parameters thus avoiding simplifying, modeldependent, assumptions. We evaluate the corresponding modelindependent constraints on the coupling constants, emphasizing the role of beam polarization, and make a comparison with the case of ee mumu.

The process eeto bartc in topcolorassisted technicolor models ; We consider the flavor changing neutral currentFCNC process eetobartcor tbarc in the context of topcolorassisted technicolorTC2 models. We find that the contributions of charged scalars technipions and toppions and topcolor gauge bosons are negligibly small. The neutral scalars toppion pit0 and topHiggs ht0 can give significant contributions to this process. With reasonable values of the parameters in TC2 models, there will be several tens of the observable bartc events to be generated in the future ee linear colliders.

Neutrino masses through seesaw mechanism in 331 models ; Some years ago it was shown by Ma that in the context of the electroweak standard model there are, at the tree level, only three ways to generate small neutrino masses by the seesaw mechanism via one effective dimensionfive operator. Here we extend this approach to 331 chiral models showing that in this case there are several dimensionfive operators and we also consider their tree level realization.

The Z to b barb Decay Asymmetry and LeftRight Models ; It has been pointed out recently by Chanowitz that the Z to bbarb decay asymmetry poses a problem for the standard model whether it is genuine or not Chanowitz2001bv. If this conflict is interpreted as new physics in the bquark couplings, it suggests a rather large right handed coupling of the bquark to the Zboson. We show that it is possible to accommodate this result in leftright models that single out the third generation.

New physics effects in Lambdab Lambda l l decay with lepton polarizations ; We study lepton polarization asymmetries in the Lambdab Lambda l l decay using the most general model independent effective Hamiltonian. The dependence of the lepton polarizations and their combinations on the new Wilson coefficients are studied in detail. It is observed that there is a region for the new Wilson coefficients for which the branching ratio coincides with the standard model prediction, while lepton polarizations show considerable departure from standard model.

Slepton and NeutralinoChargino Coannihilations in MSSM ; Within the lowenergy effective Minimal Supersymmetric extension of Standard Model effMSSM we calculated the neutralino relic density taking into account sleptonneutralino and neutralinocharginoneutralino coannihilation channels. We performed comparative study of these channels and obtained that both of them give sizable contributions to the reduction of the relic density. Due to these coannihilation processes some models mostly with large neutralino masses enter into the cosmologically interesting region for relic density, but other models leave this region. Nevertheless, in general, the predictions for direct and indirect dark matter detection rates are not strongly affected by these coannihilation channels in the effMSSM.

Electric Charge Quantization and Extra Dimensions ; In models with flat extra dimensions tiny Dirac neutrino masses can be generated via the coupling of four dimensional Standard Model fields to a higher dimensional fermion. Here we argue that, in spite of the Dirac nature of the neutrino, quantization of the electric charge can still be understood as a result of anomaly cancellation, charge conservation and naturalness requirements.

Generating the primordial curvature perturbation from inflation ; The scaleindependence of the primordial curvature perturbation suggests that it comes from the vacuum fluctuation during inflation of a light scalar field. This field may be the inflaton, or a different curvaton' field. The observation of primordial nongaussianity would be a smoking gun for the curvaton model, while the observation of gravitational waves originating during slowroll inflation would rule out the model.

Selfconsistent model of fermions ; A composite model of the fundamental fermions based on colour preons is discussed. It is found that, if endowed with the pairwise repulsiveattractive chromoelectric fields, preons would cohere in a series of structures, resembling by their properties the three generations of the fundamental fermions. The model is selfconsistent in the sense that it makes no use of free or experimental input parameters.

Assisted Tachyonic Inflation ; The model of inflation with a single tachyon field generates larger anisotropy and has difficulties in describing the formation of the Universe . In this paper we consider a model with multi tachyon fields and study the assisted inflationary solution. Our results show that this model satisfies the observation.

tb W h0 and tb W A0 decays and possible CP violating effects ; We study the charged tb W h0 and tb W A0 decays in the framework of the general two Higgs doublet model, so called model III and beyond. Here, we take the Yukawa couplings complex and introduce a new complex parameter due to the physics beyond the model III, to switch on the CP violating effects. We predict the branching ratios as BR t b W h0 106 and BR t b W A0 108. Furthermore, we observe a measurable CP asymmetry, at the order of 102, for both decays.

Lepton flavor violation in lopsided models and a neutrino mass model ; A widely adopted theoretical scheme to account for the neutrino oscillation phenomena is the seesaw mechanism together with the lopsided'' mass matrices, which is generally realized in the framework of supersymmetric grand unification. We will show that this scheme leads to large lepton flavor violation at low energy if supersymmetry is broken at the GUT or Plank scale. Especially, the branching ratio of muto egamma already exceeds the present experimental limit. We then propose a phenomenological model, which can account for the LMA solution to the solar neutrino problem and at the same time predict branching ratio of muto egamma below the present limit.

The radiative h0 A0to decays in the two Higgs doublet model ; We study the radiative h0 A0to gammagamma decays in the framework of the general two Higgs doublet model, the socalled model III. We estimate the decay width of the processes at the order of magnitude of 102 GeV for the intermediate values of the Yukawa couplings. We observe that the analysis of the two photon system provide a comprehensive information for the complex nature of the Yukawa couplings and therefore, the source of the CP violation.

Neutrino Magnetic Moments and Minimal Supersymmetric SO10 Model ; We examine supersymmetric contributions to transition magnetic moments of Majorana neutrinos. We first give the general formula for it. In concrete evaluations, informations of neutrino mass matrix elements including CP phases are necessary. Using unambiguously determined neutrino mass matrices in recently proposed minimal supersymmetric SO10 model, the transition magnetic moments are calculated. The resultant neutrino magnetic moments are found to be roughly an order of magnitude larger than those calculated in the standard model extended to incorporate the seesaw mechanism.

Scalar field perturbations in fresh inflation ; The model of fresh inflation with increasing cosmological parameter provides sufficient efolds to solve the flatnesshorizon problem and the density fluctuations agree with experimental values. In this model the temperature increases during inflation and reach its maximum value when inflation ends where the number of efolds is Nte gg 60. The most important characteristic of this model is that provides a natural transition between the end of inflation and the epoch when the universe is radiation dominated.

The MSSM with NonUniversal Higgs Masses ; I review a generalization of CMSSMmSUGRA model in which the Higgs masses are let to be free, namely the Non Universal Higgs Masses NUHM model. In our study we explore this model by employing constraints from cosmology as well as from particle physics to restrict the parameter space. We also calculate the neutralinoproton cross section in the allowed regions.

A different seesaw formula for neutrino masses ; In a wide class of unified models there is an additional and possibly dominant term in the neutrino mass formula that under the simplest assumption takes the form Mnu MN MNTuMG, where MN is the neutrino Dirac mass matrix, and u OMW. This makes possible highly predictive models. A generalization of this form yields realistic neutrino masses and mixings more readily than the usual seesaw formula in some models.

Fermion Masses and Mixings in the Little Flavon Model ; We present a complete analysis of the fermion masses and mixing matrices in the framework of the little flavon model. In this model textures are generated by coupling the fermions to scalar fields, the little flavons, that are pseudoGoldstone bosons of the breaking of a global SU6 symmetry. The Yukawa couplings arise from the vacuum expectation values of the flavon fields, their sizes controlled by a potential a la ColemanWeinberg. Quark and lepton mass hierarchies and mixing angles are accomodated within the effective approach in a natural manner.

A modified clusterhadronization model ; A new phenomenological clusterhadronization model is presented. Its specific features are the incorporation of soft colour reconnection, a more general treatment of diquarks including their spin and giving rise to clusters with baryonic quantum numbers, and a dynamic separation of the regimes of clusters and hadrons according to their masses and flavours. The distinction between the two regions automatically leads to different cluster decay and transformation modes. Additionally, these aspects require an extension of individual clusterdecay channels that were available in previous versions of such models.

Doublelepton polarization asymmetries in the B K l l decay beyond the Standard Model ; General expressions for the doublelepton polarizations in the B K l l decay are obtained, using model independent effective Hamiltonian, including all possible interactions. Correlations between the averaged doublelepton polarization asymmetries and the branching ratio, as well as, the averaged singlelepton polarization asymmetry are studied. It is observed that, study of the doublelepton polarization asymmetries can serve as a good test for establishing new physics beyond the Standard Model.

RHIC data and the multichain Monte Carlo DPMJETII ; Using data from RHIC we are able to systematically improve the twocomponent Dual Parton Model DPM event generator DPMJETIII. Introducing percolation parametrized as fusion of chains the model describes multiplicities and pseudorapidity distributions in nucleusnucleus collisions at all centralities. Guided by the dAu data from RHIC we recalibrate the model to obtain collision scaling in hA and dA collisions.

Towards a fragmentation model for Sherpa ; Some results highlighting the status of a new version of a cluster fragmentation model for the Monte Carlo event generator Sherpa are presented. In its present version this model is capable of simulating ee annihilation events into lightquark and gluon jets. We compare results for different multiplicity and momentum distributions to available SLD and LEP data as well as to results obtained with Herwig and Pythia.

Lepton flavor violating Zto l1 l2 decay in the general two Higgs Doublet model with the inclusion of nonuniversal extra dimensions ; We predict the branching ratios of Z epm mupm, Z epm taupm and Z mupm taupm decays in the model III version of the two Higgs doublet model, with the inclusion of one and two spatial nonuniversal extra dimensions. We observe that the the branching ratios are not sensitive to a single extra dimension, however, this sensitivity is considerably large for two extra dimensions.

Symmetry Nonrestoration at High Temperature in Little Higgs Models ; A detailed study of the high temperature dynamics of the scalar sector of Little Higgs scenarios, proposed to stabilize the electroweak scale, shows that the electroweak gauge symmetry remains broken even at temperatures much larger than the electroweak scale. Although we give explicit results for a particular modification of the Littlest Higgs model, we expect that the main features are generic. As a spinoff, we introduce a novel way of dealing with scalar fluctuations in nonlinear sigma models, which might be of interest for phenomenological applications.

Composite Vector Mesons and the Little Higgs Mechanism ; I review a technique to embed vector mesons in the chiral Lagrangian of QCD, and apply it to more general coset spaces, relevant for Little Higgs models. The implementation of heavy spin1 fields in Little Higgs models allows for a better control over previously non calculable, ultraviolate sensitive quantities, such as the Higgs couplings. A relevant application is the study of vacuum alignment in the SU6Sp6 models.

A model for leptogenesis at the TeV scale ; We consider the mechanism of thermal leptogenesis at the TeV scale in the context of an extension of the Standard Model with 4 generations and the inclusion of four righthanded Majorana neutrinos. We obtain a value for the baryon asymmetry of the Universe in accordance with observations by solving the full set of coupled Boltzmann equations for this model.

Flavor structure of pentaquark baryons in quark model ; The flavor SU3 group structure of pentaquark baryons which form bm1, bm8, bm10, barbm10, bm27, and bm35 multiplets is investigated in quark model. The flavor wave functions of all the pentaquark baryons are constructed in SU3 quark model and their Yukawa interactions with meson octet are obtained in general and in the special case of the octetantidecuplet ideal mixing with the OZI rule. The mass sum rules of pentaquark baryons are also discussed.

Bmeson signatures of a Supersymmetric U2 flavor model ; We discuss Bmeson signatures of a Supersymmetric U2 flavor model, with relatively light electroweak scale masses third generation righthanded scalars. We impose current B and K meson experimental constraints on such a theory, and obtain expectations for BXs gamma, BXs glue, BXs l l, Bphi Ks, BsBsbar mixing, and the dilepton asymmetry in Bs. We show that such a theory is compatible with all current data, and furthermore, could reconcile the apparent deviations from Standard Model predictions that have been found in some experiments.

Unitarity violation of the CKM matrix in a nonuniversal gauge interaction model ; We explore the unitarity violation of the CKM matrix in the model in which the third generation fermions are subjected to the separate SU2L gauge interaction. With the recent LEP and SLC data at Zpole and lowenergy neutral current interaction data, the analysis on the parameter space of the model is updated, and the unitary violation is predicted under the constraint.

Dark Energy in an Axion Model with Explicit ZN Symmetry Breaking ; We point out that a well known axion model with an explicit ZN symmetry breaking term predicts both dark energy and cold dark matter. We estimate the parameters of this model which fit the observed densities of the dark components of the universe. We find that the parameters do not conflict with any observations.

Constituent quark model study of the meson spectra ; The qbar q spectrum is studied in a generalized constituent quark model constrained in the study of the NN phenomenology and the baryon spectrum. An overall good fit to the available experimental data is obtained. A detailed analysis of all sectors from the lightpseudoscalar and vector mesons to bottomonium is performed paying special attention to the existence and nature of some non wellestablished states. These results should serve as a complementary tool in distinguishing conventional quark model mesons from glueballs, hybrids or multiquark states.

Electroproduction of Vector Mesons at Small x ; Vector meson electroproduction is analyzed within the twogluon 2G model and the generalized parton distribution GPD approach at small xBjorken. We demonstrate that 2G and GPD models are not completely equivalent. At the same time, both models are in reasonable agreement with available experimental data on light vector meson electroproduction.

Heavy Antiquark Pentaquarks in the CM and GB Models ; The splittings between positive parity pentaquarks containing a single heavy c,b antiquark and four light u,d quarks are investigated in models having spindependent interactions generated by either effective Goldstone boson exchange or effective color magnetic exchange. Modelindependent features of these splittings are emphasized. Overlaps to the fallapart'' decay configurations ND, ND or NB, NB, relevant to decay couplings for the various 2body pentaquark decays, are also computed.

EDM constraints and CP asymmetries of B processes in supersymmetric models ; We demonstrate that electric dipole moments EDMs strongly constrain possible SUSY contributions to the CP asymmetries of B processes; LL andor RR flavour mixings between second and third generations are severely restricted by the experimental limit on the mercury EDM, and so therefore are their possible contributions to the CP asymmetries of B phi K and B eta' K. We find that SUSY models with dominant LR and RL mixing through nonuniversal Aterms is the only way to accommodate the apparent deviation of CP asymmetries from those expected in the Standard Model without conflicting with the EDM bounds or with any other experimental results.

A Single Scalar Field Model of Dark Energy with Equation of State Crossing 1 ; In this paper we study the possibility of building models of dark energy with equation of state across 1 and propose explicitly a model with a single scalar field which gives rise to an equation of state larger than 1 in the past and less than 1 at the present time, consistent with the current observations.

Comments related to reading Static quantities of the W boson in the SUL3times UX1 model with righthanded neutrinos ; Comments related to reading the paper Static quantities of the W boson in the SUL3times UX1 model with righthanded neutrinos, hepph0312308 by J. L. GarciaLuna et al are given. They do not concern the main results of the paper but a statement there about the Higgs sector of the 331 model with righthanded neutrinos. The scalar sextet introduced here may help us to generate neutrino masses in an acceptable range.

Doublelepton polarization asymmetries in the Exclusive B rho l l decay beyond the Standard Model ; The doublelepton polarization asymmetries in B rho l l decay is analyzed in a model independent framework. The general expressions for nine doublepolarization asymmetries are calculated. It is shown that the study of the doublelepton polarization asymmetries proves to be very useful tool in looking for new physics beyond the standard model.

Split Supersymmetry at Colliders ; We consider the collider phenomenology of splitsupersymmetry models. Despite the challenging nature of the signals in these models the longlived gluino can be discovered with masses above 2 TeV at the LHC. At a future linear collider we will be able to observe the renormalization group effects from split supersymmetry on the charginoneutralino mixing parameters, using measurements of the neutralino and chargino masses and cross sections. This indirect determination of charginoneutralino anomalous Yukawa couplings is an important check for supersymmetric models in general.

SO10GUT Coherent Baryogenesis ; A model for GUT baryogenesis, coherent baryogenesis within the framework of supersymmetric SO10, is considered. In particular, we discuss the BarrRaby model, where at the end of hybrid infl ation charge asymmetries can be created through the timedependent higgsinogaugino mixing mass matrix. These asymmetries are processed to Standard Model matter through decays via nonrenormalizable BLviolating operators. We find that a baryon asymmetry in accordance with observation can be generated. An appendix is devoted to provide useful formulas and concrete examples for calculations within SO10.

Resolved photon and multicomponent model for p and total cross section ; We generalize our previous model for gamma p scattering to gamma gamma scattering. Performing a new simultaneous fit to gamma p and gamma gamma total cross section we find an optimal set of parameters to describe both processes. We propose new measures of factorization breaking for gamma gamma collisions and present results for our new model.

A Supersymmetric 331 model with MSSMlike Scalar Sector ; We present a supersymmetric 331 model with exotic quarks and a charged lepton as an extension of the MSSM model with anomaly free three generations The scalar sector is studied with six triplet Higgses and the mass spectrum for light Higgs scalars are found to obey MSSM like predictions .The trilinear Higgs term in 331 is found to be consistent with the bilinear mHuHd term of MSSM and play an important role in the treelevel mass spectrum of scalars.

Covariant oscillator quark model for glueballs and baryons ; An analytic resolution of the covariant oscillator quark model for a threebody system is presented. Our harmonic potential is a general quadratic potential which can simulate both a deltashape configuration or a simplified Yconfiguration where the junction is located at the center of mass. The mass formulas obtained are used to compute glueball and baryon spectra. We show that the agreement with lattice and experimental data is correct if the Casimir scaling hypothesis is assumed. It is also argued that our model is compatible with pomeron and odderon approaches.

New proposal of numerical modelling of BoseEinstein correlations BoseEinstein correlations from within ; We describe an attempt to numerically model BoseEinstein correlations BEC from within, i.e., by using them as the most fundamental ingredient of a Monte Carlo event generator MC rather than considering them as a kind of more or less important, depending on the actual situation afterburner, which inevitably changes the original physical content of the MC code used to model multiparticle production process.

Maximal Neutrino Mixing from Discrete Symmetry in Extra Dimensions ; I review the construction of a model for lepton masses based on the flavour symmetry group A4 x U1 reproducing the socalled tribimaximal lepton mixing scheme, in eccelent agreement with current data. The model predicts a neutrino spectrum of normal hierarchy type, not far from degenerate. A testable relation between neutrino masses is obtained. I shortly discuss also general requirements for models based on spontaneously broken flavour symmetries, in order to get a maximal atmospheric mixing angle.

Holographic Model for Mesons at Finite Temperature ; A holographic model of QCD at finite temperature is proposed and thermal properties for light mesons are examined in terms of this model. We find interesting temperature dependences of masses and decay constants for several mesons, and NambuGoldstone theorem for the chiral symmetry breaking and generalized GellMannOakesRenner relation are assured at finite temperature. Furthermore, we can see in the chiral limit that the speed of the pion in the thermal medium decreases to zero when the temperature approaches to the critical point of quark confinement and deconfinement transition, where the chiral symmetry is restored.

Constraints on UED KKneutrino dark matter from magnetic dipole moments ; Generically, universal extra dimension UED extensions of the standard model predict the stability of the lightest KaluzaKlein KK particle and hence provide a dark matter candidate. For UED scenarios with one extra dimension, we modelindependently determine the size of the induced dimensionfive magnetic dipole moment of the KKneutrino, nu1. We show that current observational bounds on the interactions of dipole dark matter place constraints on UED models with KKneutrino dark matter.

Semileptonic decays of baryons in a relativistic quark model ; We calculate semileptonic decays of light and heavy baryons in a relativistically covariant constituent quark model. The model is based on the BetheSalpeterequation in instantaneous approximation. It generates satisfactory mass spectra for mesons and baryons up to the highest observable energies. Without introducing additional free parameters we compute on this basis helicity amplitudes of electronic and muonic semileptonic decays of baryons. We thus obtain form factor ratios and decay rates in good agreement with experiment.

High energy GammaRay Bursts as a result of the collapse and total annihilation of neutralino clumps ; Rare astrophysical events cosmological gammaray bursts with energies over GeV are considered as an origin of information about some SUSY parameters. The model of generation of the powerful gammaray bursts is proposed. According to this model the gammaray burst represents as a result of the collapse and the total annihilation of the neutralino clump. About 80 of the clump mass radiates during about 100 second at the final stage of annihilation. The annihilation spectrum and its characteristic energies are calculated in the framework of Split Higgsino model.

A vertexstructure model for new direct CPviolating effects in Bbar0B0 phi KS and in B pi eta' eta ; We consider effective Lagrangian models of CPviolating vertex structure in which a b uW vertex, proportional to s13eidelta13 with s13 very small milliweak interaction and delta13 large, is dynamically generated. A consequent, enhanced CPviolating vertex for bto sg results in an enhanced CPviolating phase in the ratio of amplitudes for bbar to phi KS. We estimate that this can significantly change the S parameter from the value expected in the standard model.

Radial Flow in a Final State Interaction Model ; In the framework of a final state interaction model, we show that the socalled radial flow, i.e. the almost linear increase of the inverse slope T with the mass of the produced particle, is already contained in the initial condition with a slope ut2 the socalled strength of the average radial transverse flow which is larger than the measured one. While the precise value of the slope depends on the details of the model, the above result has a very general basis namely the increase with increasing pT of the fixed pT suppression, in the low pT region.