bluuebunny/crossref_metadata_2025 huggingface dataset:
RENORMALIZATION GROUP EQUATIONS AND DECONFINEMENT IN FINITE TEMPERATURE QCD
Authors: SONG GAO , LI JIARONG
Published: November 2004

Finite temperature renormalization group equations are employed to investigate the behavior of the effective coupling constant and anomalous dimension in SU c(3) gauge field at finite temperature. On the basis of this, the deconfinement of high temperature QCD is discussed.
Z–Z' MIXING IN EXTENDED GAUGE MODELS FROM LEP 1990 DATA
Authors: BHATTACHARYA G. , DATTA A. , GANGGUL S. N. , RAYCHAUDHURI A.
Published: November 2004

We have studied Z–Z' mixing in the extended gauge models of left-right and extra U(1) types. This has been carried out by performing simultaneous fits to the combined data of cross sections and asymmetries from the four LEP experiments which have collected over 550,000 Z0 decays in 1990. Two methods have been adopted to determine the mixing angle ξ0 by carrying out: (a) Standard Model dependent fits, where we calculate ρf and sin 2θf from the Standard Model, and (b) Standard Model independent fit, where we keep [Formula: see text] and [Formula: see text] as free parameters. Fitted values of the mixing angle ξ0, and deviation of the ρ parameter due to Z–Z' mixing are discussed.
CAUSAL PRESCRIPTION FOR THE LIGHT-CONE GAUGE
Authors: PIMENTEL B. M. , SUZUKI A. T.
Published: November 2004

We present a prescription for light-cone gauge singularities which embeds in it causality and show that it results in simpler and less demanding integrals to be performed.
A REMARK ON SPIN AND STATISTICS OF BABY SKYRMION
Authors: OTSU HIDEHARU , SATO TOSHIRO
Published: November 2004

We study spin and statistics of baby skyrmion, which is a topological soliton solution in the (2+1)-dimensional O(3) σ-model. It is shown that the Hopf term written in terms of CP 1 variables does not naively represent the topological charge associated with the non-triviality of Π1 (S2 → S2). It is also pointed out, therefore, that the baby skyrmion cannot behave as anyon, even if the Hopf term of CP 1 variables is added to the model.
STATISTICS AND SPIN ON TWO-DIMENSIONAL SURFACES
Authors: BALACHANDRAN A. P. , EINARSSON T. , GOVINDARAJAN T. R. , RAMACHANDRAN R.
Published: November 2004

The fundamental groups of the configuration spaces for the O(3) nonlinear σ-model on the compact genus g surfaces [Formula: see text] and on the connected sums [Formula: see text] are known for any soliton number N. So are the braid for N spinless particles on these manifolds. The representations of these groups govern the possible statistics of solitons and particles. We show that when spin and creation/annihilation processes are introduced, the fundamental groups for the particles are the same as the corresponding σ-model groups. These fundamental groups incorporate the spin-statistics connection and are of greater physical relevance than the standard braid groups.
CONNECTING RANDOM MATRIX AND TOPOLOGICAL LG MODELS VIA INTEGRABILITY
Authors: HERZIG K. , WEISSGOLD M. , TATARU-MIHA P.
Published: November 2004

We prove that a bi-Hamiltonian system (e.g., a KdV system) is integrable if and only if its Krichever–Moser–Jacobi matrix L has a double eigenvalue, i.e., if (the characteristic polynomial of) L has rational double point singularities. Therefore, L (precisely, its characteristic polynomial) can be identified with the potential of a Landau–Ginzburg (LG) topological model with the same (rational double point) singularity. A rational curve is naturally defined in the corresponding Kummer variety and this explains the appearance (or non-appearance) of the doubling of the string equation as well as a phenomenon observed by Eguchi et al. Finally, we point out a parallelism between rational two-dimensional theories and rational singularities.
TARGET SPACE DUALITY AND STRINGY BLACK HOLES
Authors: GIVEON AMIT
Published: November 2004

Target space duality symmetry of the SL (2,ℝ)/ U (1) background leads to stringy properties of the black hole. For a Euclidean space-time the semi-infinite cigar is transformed to an infinite funnel. High and low temperatures of the black hole are related. For a Lorentzian space-time, duality interchanges regions I and V in the Kruskal–Szekeres coordinates, that is, duality exchanges the horizon with the singularity. As a result, a signal can be sent out of the singularity. Such a signal is associated with the string winding modes. The mass of the black hole and the consequence of a tachyon disturbance are discussed.
A POSSIBLE CONNECTION BETWEEN CLASSICAL INTEGRABILITY AND QUANTUM SOLVABILITY FOR DYNAMICAL SYSTEMS IN TWO DIMENSIONS
Authors: KAUSHAL R. S. , PARASHAR D.
Published: November 2004

Within the framework of a simple ansatz for the eigenfunction we try to understand the relationship between the classical integrability and the quantum solvability (i.e., the existence of a normalizable solution to the Schrödinger wave equation with nonzero eigenvalues) of a dynamical system in two dimensions. As an example, the case of an inverse harmonic oscillator potential, which is found to be classically integrable and also quantum solvable, is discussed.
W-ALGEBRA REALIZATIONS AND W-GRAVITY ANOMALIES
Authors: HULL C. M. , PALACIOS L.
Published: November 2004

The coupling of scalars fields to chiral W3 gravity is reviewed. In general the quantum current algebra generated by the spin-two and three currents does not close when the "natural" regularization (corresponding to the normal ordering with respect to the modes of ∂ϕi) is used, and the non-closure reflects matter-dependent anomalies in the path integral quantization. We consider the most general modification of the current, involving higher derivative "background charge" terms, and find the conditions for them to form a closed algebra in the "natural" regularization. These conditions can be satisfied only for the two-boson model. In that case, it is possible to cancel all the matter-dependent anomalies by adding finite local counter terms to the action and modifying the transformation rules of the fields.
EXPERIMENTAL PERFORMANCE OF THE DELPHI DETECTOR AT LEP
Authors: BENLLOCH JOSÉ M.
Published: November 2004

A summary of the configuration and performance of the detectors of the DELPHI experiment site in LEP is presented after the first two years of operation of the accelerator.
THE BLACK HOLE ENTROPY BOUND AND THE MAXIMUM TEMPERATURE FOR MESON FORMATION IN THE NUCLEAR FIREBALL
Authors: DEY JISHNU , DEY MIRA , SCHIFFER MARCELO , TOMIO LAURO
Published: November 2004

The entropy bound from black hole thermodynamics can be invoked to set limits for temperatures at which hadrons can survive as a confined system. We find that this implies that the pion can be formed in heavy ion collisions, much later than heavier mesons, for example the ρ-meson, when the fireball is cooler. The temperature found in a simple model agree qualitatively with experiment. We also suggest that this may be the reason why in pion interferometry experiments the space-time volume of the pion source seems large.
PHYSICAL PROPERTIES OF W GRAVITIES AND W STRINGS
Authors: DAS SUMIT R. , DHAR AVINASH , RAMA S. KALYANA
Published: November 2004

We investigate some basic physical properties of W gravities and W strings, using a free field realization. We argue that the configuration space of W gravities have global characteristics in addition to the Euler characteristic. We identify one such global quantity to be a "monopole" charge and show how this charge appears in the exponents. The free energy would then involve a "θ" parameter. Using a BRST procedure we find all the physical states of W3 and W4 gravities, and show that physical operators are nonsingular composites of the screening charge operators. (The latter are not physical operators for N≥3.) For W strings we show how the W constraints lead to the emergence of a single (and not many) extra dimension coming from the W-gravity sector. By analyzing the resulting dispersion relations we find that both the lower and upper critical dimensions are lowered compared to ordinary two-dimensional gravity. The pure W gravity spectrum reveals an intriguing "numerological" connection with unitary minimal models coupled to ordinary gravity.
ON SPONTANEOUS PARITY BREAKING IN THREE-DIMENSIONAL GAUGE-HIGGS SYSTEMS
Authors: AMBJØRN J. , FARAKOS K. , SHAPOSHNIKOV M. E.
Published: November 2004

We address the question of spontaneous breaking of parity in three-dimensional Euclidean SU(2) gauge-Higgs theory by Monte–Carlo simulations. We observe no sign of spontaneous parity breaking in the behavior of local gauge invariant operators. However, the presence of parity-odd terms in the action can induce a phase transition to a parity-odd ground state.
HIGHER ORDER PARASUPERSYMMETRIC QUANTUM MECHANICS
Authors: DURAND STÉPHANE , MAYRAND MICHEL , SPIRIDONOV VYACHESLAV , VINET LUC
Published: November 2004

A class of Hamiltonians with parasupersymmetry of order p is presented and algebraically characterized. Conformal invariant cases are discussed.
RHO-MESON-NUCLEON COUPLING IN RELATIVISTIC MEAN FIELD THEORY
Authors: PATRA S. K. , PRAHARAJ C. R.
Published: November 2004

We obtain a more accurate rho-meson-nucleon coupling constant gρ for studying nuclei in relativistic mean field theory of nucleons and mesons than used before. With this gρ we get a better description of finite nuclei. We have studied a number of isotopic chains of neutron-rich nuclei using the new gρ parameter, with important consequences for very neutron-rich exotic nuclei and the neutron-drip line. The binding energies are sensitive to the coupling constant gρ, but the rms radii and deformation parameters of nuclei are not at all sensitive to gρ.
't HOOFT'S SCATTERING AMPLITUDE FROM CHERN–SIMONS–WITTEN GRAVITY IN 2+1 DIMENSIONS
Authors: FALBO-KENKEL M. K. , MANSOURI F.
Published: November 2004

By using canonical phase space variables different from those associated with individual particles, we couple the Chern–Simons–Witten gravity to point-like sources. The resulting theory provides an alternative to the usual test particle approximation and yields 't Hooft's scattering amplitude in the limit of two very massive slowly moving particles.
EVIDENCE FOR A NEUTRINO WITH A MASS OF 17 keV
Authors: LOGAN B. A. , LJUBIČIĆ A.
Published: November 2004

The possible existence of neutrinos with a mass of 17 keV would have profound consequences for particle physics, astrophysics, and cosmology. Although several recent investigations have found evidence that about 1% of neutrinos have a 17 keV mass, other investigations have given negative results. In this review we summarize the evidence both for, and against, the existence of such a neutrino.
FRAGMENTATION OF SILICON NUCLEI AT 4.5 A GeV/c
Authors: AHMAD TAUSEEF , IRFAN M.
Published: November 2004

1024 interactions caused by 4.5 A GeV/c 28Si in emulsion are studied. Result on the mean free path is discussed and compared with the corresponding results obtained for the interactions initiated by other projectiles. Multiplicity distributions for Z=1,2 and [Formula: see text] fragments are also investigated.
GENERATION AS THE ORIGIN OF HIGGS FIELDS
Authors: IZAWA K.-I.
Published: November 2004

This letter provides a simple reformulation of the standard electroweak theory of leptons with two generations as a generalized gauge theory. It is based on a discrete analogue of Kaluza–Klein theories, with the 'extra dimension' being the generations of the matter. Higgs fields appear as part of a generalized gauge field. Hypercharge quantization results from the use of a simple Lie superalgebra su(1|2) as the generalized gauge algebra.
A GEOMETRIC INTERPRETATION FOR THE TORSION CONSTRAINTS OF (2,0) HETEROTIC WORLDSHEET SUPERGRAVITY
Authors: GOVINDARAJAN SURESH , OVRUT BURT A.
Published: November 2004

We present a geometric interpretation for the torsion constraints in (2,0) supergravity using G-structures. This leads to a classification of the constraints as given by Ref. 1. We also present the essential torsion constraints for (p,q) geometry.
LIGHT TOP QUARK AND LIGHT CHARGED HIGGS REVISITED
Authors: JOSHIPURA ANJAN S. , RINDANI SAURABH D.
Published: November 2004

A model with two Higgs doublets is presented where a discrete symmetry is imposed so that the flavor-changing neutral currents in the down-quark sector are naturally suppressed and obey a hierarchy determined by the hierarchy of the Kobayashi-Maskawa matrix elements. The fermion couplings to charged-Higgs bosons are different from those in models with natural flavor conservation. As a consequence, it is possible to have a light top quark which evades the Tevatron limit by decaying predominantly into a light charged Higgs with mass M H ≤ mt - mb. The model is also consistent with data on ε and [Formula: see text] mixing for a wide range of M H and the ratio of vacuum expectation values of the scalar fields.
MANIFESTLY O(d,d) INVARIANT APPROACH TO SPACE-TIME DEPENDENT STRING VACUA
Authors: MEISSNER K. A. , VENEZIANO G.
Published: November 2004

An O(d,d) symmetry of the manifold of string vacua that do not depend on d (out of D) space-time coordinates has been recently identified. Here we write down, for d=D-1, the low energy equations of motion and their general solution in a manifestly O(d,d)-invariant form, pointing out an amusing similarity with the renormalization group framework. Previously considered cosmological and black hole solutions are reproduced as particular examples.
SPIN-(FLAVOR) PRECESSION AND SHORT WAVELENGTH VACUUM OSCILLATION AS A SOLUTION FOR THE SOLAR NEUTRINO PUZZLE
Authors: MOHAPATRA P. K.
Published: November 2004

We investigate the possibility of spin-(flavor) precession combined with short wavelength vacuum oscillation as a solution for the solar neutrino puzzle. A large frozen-in magnetic field inside the sun with a neutrino magnetic moment of the order of 10-10 Bohr magneton can completely depolarize the νeL resulting in a factor of half of the emitted number. With a short wavelength vacuum oscillation and maximal mixing, the number of νeL's reaching the earth is reduced by another factor of half; this explains the Homestake chlorine experiment. The difference between the Homestake and the Kamiokande-II experiments can be attributed to the contribution to the Cherenkov radiation in the latter through the neutral current and electromagnetic interactions of the components which are inert in the former.
EFFECTIVE HAMILTONIAN OF THE RELATIVISTIC QUARK MODEL
Authors: CATTO SULTAN , CHEUNG HAY YEUNG , GÜRSEY FEZA
Published: November 2004

We derive an effective Hamiltonian of the relativistic quark model. In the limit of zero quark masses, we obtain linear Regge trajectories for mesons. Based on the diquark-antiquark symmetry, we show that the Regge trajectories of baryons and mesons are parallel at high angular moments. We discuss the breaking of the hadronic supersymmetry and obtain a mass relation of mesons and baryons.
VACUUM STRUCTURE IN THE QUANTUM NONLINEAR σ-MODEL
Authors: ASANO HIDEKI , KANADA HIROYUKI , SO HIROTO
Published: November 2004

The vacuum structure with a non-trivial winding number (the baryon number) of a quantum nonlinear σ-model is investigated. Some falling paths to the vacuum are found in a finite-dimensional subspace of the infinite-dimensional configuration space. It is also shown by numerical calculation that the anti-baryon density is appeared in the outer region on the way of some paths falling into the vacuum. In addition, we also discuss some configurations without hedgehog ansatz.
ONSAGER ALGEBRA AND INTERGRABLE LATTICE MODELS
Authors: AHN CHANGRIM , SHIGEMOTO KAZUYASU
Published: November 2004

We derive many integrable lattice from the Ising and superintegrable chiral Potts models using the Onsager algebra. For each of these models, we also construct a class of integrable models from the automorphisms of the Onsager algebra. The extension of the Onsager algebra and associated intergrable models are considered.
NEW SPECIAL OPERATORS IN W-GRAVITY THEORIES
Authors: RAMA S. KALYANA
Published: November 2004

We find new special physical operators of W3-gravity having non-trivial ghost sectors. Some of these operators may be viewed as the Liouville dressings of the energy operator of the Ising model coupled to two-dimensional (2D) gravity and this fills in the gap in the connection between pure W3-gravity and Ising model coupled to 2D gravity found in our previous work. We formulate a selection rule required for the calculation of correlators in W-gravity theories. Using this rule, we construct the non-ghost part of the new operators of WN-gravity and find that they represent the (N, N + 1) minimal model operators from both inside and outside the minimal table. Along the way we obtain the canonical spectrum of WN-gravity for all N.
THREE-POINT CORRELATION FUNCTIONS OF THE MINIMAL CONFORMAL THEORIES COUPLED TO 2D GRAVITY
Authors: DOTSENKO Vl. S.
Published: November 2004

The general three-point correlation functions of the minimal conformal field theories coupled to gravity are calculated using the specific Coulomb gas type quantization technique. The gravity interaction modifies in an essential way the operator algebra of the corresponding minimal model, in particular in canceling the decoupling of a finite number of primary fields, in case of rational theories. This is suggested to be related to the appearance of new physical states, under the BRST analysis of Lian and Zuckerman. Within the analytic technique, this effect is due to the corresponding singularities of the gravity sector operator algebra structure constants.
VACUUM ALIGNMENT IN THE TOP MODE STANDARD MODEL
Authors: KITAZAWA NORIAKI
Published: November 2004

We study the vacuum alignment in the top mode Standard Model in which the electroweak symmetry breaking is triggered by the top quark condensation. Including the QCD effects through the Cornwall-Jackiw-Tomboulis effective potential, we establish that the correct electroweak symmetry breaking SU (2)L × U (1)Y → U (1) em occurs in this model in 1/N leading and improved ladder approximation.
ORIGIN OF FERMION MASSES
Authors: MOFFAT J. W.
Published: November 2004

An eigenvalue equation for the spectrum of lepton and quark is obtained from a truncated set of Tamm-Dancoff integral equations, generated by a four-fermion interaction based on a finite nonlocal quantum field theory. Eigenvalue equations for the meson and baryon mass spectra are also derived and integral equations are proposed for the scattering amplitudes, which can be used to calculate coupling constants in the nonlocal version of the standard model.
ONE-LOOP CLOSED STRING 5-PARTICLE FERMION AMPLITUDES IN THE COVARIANT FORMULATION
Authors: LIN ZHONG-HENG
Published: November 2004

The closed superstring 2 fermion-3 boson and 4 fermion-1 boson scattering amplitudes at one-loop level are calculated in the covariant formulation. We use the method of Atick and Sen and find that it can be applied to 5 particles without any major difficulties. We discuss the symmetry properties of the amplitudes as a check of their correctness. From the residue of the relevant correlator for 4 fermion-1 boson scattering at the appropriate pole, we obtain the 2 fermion-2 boson amplitude which agrees with the amplitude calculated in the light-cone gauge in the Green-Schwarz formulation. The calculation requires some new θ-function identities and Fierz transformations in ten dimensions which we also prove and discuss.
FERMIONIC QUANTUM MECHANICS AND SUPERFIELDS
Authors: MARNELIUS ROBERT
Published: November 2004

The explicit forms of consistent eigenstate representations for finite dimensional fermionic quantum theories are considered in detail. In particular are the possible Grassmann characters of the eigenstates determined. A straightforward Schrödinger representation is shown to exist if they are even or odd. For an odd number of real eigenvalues, the eigenstates cannot be even or odd. Still a consistent Schrödinger picture is shown to exist provided the basic canonical operators are antilinearly represented. Since the wave functions within the Schrödinger picture are superfields, the class of superfields which also are first quantized wave functions is determined.
SUPER-LIOUVILLE THEORY AS A TWO-DIMENSIONAL, SUPERCONFORMAL SUPERGRAVITY THEORY
Authors: DISTLER JACQUES , HLOUSEK ZVONIMIR , KAWAI HIKARU
Published: November 2004

In this paper we extend our previous results on the bosonic Liouville theory, to the supersymmetric case. As in the bosonic case, we find that the quantization of the N=1 theory is limited to the region D≤1. We compute the exact critical exponents and the analogue of the Hausdorff dimension of super random surfaces. Our procedure is manifestly covariant and our results hold for the surface of arbitrary topology. We also examine the N=2, O(2) string theory and find that it appears to be well-defined for all D.
TOPOLOGY AND LATTICES
Authors: BEN-AV RADEL , SOLOMON SORIN
Published: November 2004

The concept of interpolation relates lattice configurations to continuum configurations. This relation induces from the continuum to the lattice the definitions of “continuous deformation”, topological classification and homotopy classes. The lattice homotopy classes obtained this way are separated by boundaries made out of “exceptional configurations” (EC).

The EC boundaries allow the topological classification of the lattice configurations even in models in which it is impossible (or cumbersome) to give in a close form, a definition of the topological charge in terms of lattice variables.

We give the description of the EC boundaries for the 2 dimensional XY spin model and the 4 dimensional SU(2) gauge model.
SEARCH FOR THE TRANSITION POINT AND DEDUCTION OF THE ORDER OF PHASE TRANSITIONS—APPLICATION OF THE MICROCANONICAL SIMULATION METHOD WITH FRICTION TERMS
Authors: MORIKAWA YOSHITOMI
Published: November 2004

We apply the microcanonical simulation method with friction terms to deduce the order of phase transitions by examining the existence of the S-shaped curve in the internal energy-temperature diagram. We study the dependence of the S-shape on a parameter of energy change by using a gauge model, and determine the location of the transition point. We further consider the possibility of finding out weak first-order phase transitions. We also explain several features in the method and remark a condition on the parameter for a reasonable simulation.
AN INTERPRETATION OF THE ABELIAN CHERN-SIMONS VACUUM HOLONOMY
Authors: ZEMBA GUILLERMO
Published: November 2004

It is shown that the recently discovered vacuum holonomy in the pure Abelian Chern-Simons theory in 2+1 dimensions can be interpreted as the expectation value of the holonomy operator of Wilson loops once the theory is defined on a constant time plane. This may be accomplished by a prescription that connects the two- and three-dimensional points of view. The projected holonomy is framing-dependent and coincides with the previous result if a canonical framing is used. A physical model is considered to discuss its physical significance.
RENORMALIZATION GROUP AND STRING LOOPS
Authors: TSEYTLIN A.A.
Published: November 2004

The fixed points of the 2-d renormalization group flow are known to correspond to the tree level string vacua. We analyze how the “renormalization group” (or “sigma model”) approach can be extended to the string loop level. The central role of the condition of renormalizability of the generating functional for string amplitudes with respect to both “local” and “modular” infinities is emphasized. Several one- and two-loop examples of renormalization are discussed. It is found that in order to ensure the renormalizability of the generating functional one is to use “extended” (e.g. Schottky-type) parametrizations of moduli spaces. An approach to a resummation of the string perturbative expansion based on operators of insertion of topological fixtures is suggested.
QUASI-EXACTLY-SOLVABLE QUANTAL PROBLEMS: ONE-DIMENSIONAL ANALOGUE OF RATIONAL CONFORMAL FIELD THEORIES
Authors: MOROZOV A. YU. , PERELOMOV A.M. , ROSLY A.A. , SHIFMAN M.A. , TURBINER A.V.
Published: November 2004

The class of quasi-exactly-solvable problems in ordinary quantum mechanics discovered recently shows remarkable parallels with rational two-dimensional conformal field theories. This fact suggests that investigation of the quasi-exactly-solvable models may shed light on rational conformal field theories. We discuss a relation between these two theoretical schemes and propose a mathematical formulation for the procedure of constructing quasi-exactly solvable systems. This discussion leads us to a kind of generalization of the Sugawara construction.
CHARACTER FORMULAS OF AN EXTENDED SUPERCONFORMAL ALGEBRA RELEVANT TO STRING COMPACTIFICATION
Authors: ODAKE SATORU
Published: November 2004

We present the character formulas of the c=9 algebra, which is an extended algebra obtained by adding the spectral flow generators to the N=2 superconformal algebra.

We also describe their modular transformation properties.
CHERN-SIMONS THEORY AND KAUFFMAN POLYNOMIALS
Authors: WU YONG-SHI , YAMAGISHI KENGO
Published: November 2004

We report on a study of the expectation values of Wilson loops in D=3 Chern-Simons theory. The general skein relations (of higher orders) are derived for these expectation values. We show that the skein relations for the Wilson loops carrying the fundamental representations of the simple Lie algebras SO(n) and Sp(n) are sufficient to determine invariants for all knots and links and that the resulting link invariants agree with Kauffman polynomials. The polynomial for an unknotted circle is identified to the formal characters of the fundamental representations of these Lie algebras.
THE REPRESENTATION THEORY OF THE SO(3) INVARIANT SUPERCONFORMAL ALGEBRA
Authors: MIKI KEI
Published: November 2004

The representation theory of the SO(3) invariant superconformal algebra is discussed. The necessary and sufficient condition of unitarity, the Kac determinants, the character formulae for unitary representations and their modular transformation laws are obtained under some assumptions.
CHIRAL (SUPER) STRING ACTIONS
Authors: KUZENKO S.M. , SOLOVIEV O.A.
Published: November 2004

We present a covariant action describing chiral bosonic string theories in space-time dimensions d<26 and a covariant (1, 0) supersymmetric action describing heterotic string theories in space-time of dimension d<10. The anomaly cancellation conditions are found. In the four-dimensional case the supersymmetric action corresponds to the SO(44) heterotic string theory.
CHARMED BARYONS: A NEW LABORATORY FOR CHARM STUDIES
Authors: KLEIN SPENCER R.
Published: November 2004

Recent results involving charmed baryons are discussed. In the past few years, many groups have new, higher statistics studies of the [Formula: see text] and Σc. Accurate mass measurements and more quantitative results on branching ratios have appeared. The new [Formula: see text] relative branching ratios are compared with theoretical predictions from quasi-two body calculations and statistical models. Absolute [Formula: see text] branching ratios are discussed, and various methods for setting an absolute scale are compared. New measurements of the Σc mass and production are discussed, and compared with theoretical models. The recent observation of the [Formula: see text], [Formula: see text], and Ωc allow a discussion of the charmed baryon mass spectrum. These recent measurements are compared with a number of theoretical predictions, both for the absolute masses and for mass splittings among multiplets. Finally, prospects for the future studies of charmed baryons are discussed.
THE SUPERSYMMETRIC CURCI-PAFFUTI RELATION AND VANISHING OF THE DILATON BETA FUNCTION IN THE N=2 SUSY SIGMA MODEL
Authors: HAAGENSEN PETER E.
Published: November 2004

We extend the Curci-Paffuti relation of bosonic sigma models to the supersymmetric case. In the N=1 model, a similar relation is found, while in the N=2 model, a vanishing result ensues for the dilaton β-function. One contribution to the dilaton β-function in the N=2 model is identified as a previous result of Grisaru and Zanon; however, if we remain within a minimal subtraction scheme, other terms coming from finite subtractions appear which precisely cancel that and give a vanishing result. This is in agreement with a recent result of Jack and Jones.
HIGHER CURVATURE SUPERGRAVITY AND THE MASSLESS SECTOR OF SUPERSTRING THEORIES.: HAMILTONIAN FORMALISM
Authors: FOUSSATS A. , ZANDRON O.
Published: November 2004

Starting from a geometrical and polynomial first-order formalism of supergravity, linear in the Riemann curvature, we construct a higher curvature supergravity which has also a polynomial Lagrangian. Next, by means of the resulting torsion equation, we show that it is possible to obtain the second order formalism which exhibits a nonpolynomial structure. The nonpolynomial second order formalism can be confronted and related to the massless sector of effective superstring field theories. This is done in the Hamiltonian framework.
STRING FIELD THEORY AT D < 26
Authors: CHUNG WON-SANG , KIM JAE-KWAN
Published: November 2004

The 3-string vertex for the non-critical string theory is constructed and is shown to be BRST invariant at D < 26.
SUPERSYMMETRY, REFLECTIONLESS SYMMETRIC POTENTIALS AND THE INVERSE METHOD
Authors: BAGCHI B.
Published: November 2004

The role of inverse scattering method is illustrated to examine the connection between the multi-soliton solutions of Korteweg-de Vries (KdV) equation and discrete eigenvalues of Schrödinger equation. The necessity of normalization of the Schrödinger wave functions, which are constructed purely from a supersymmetric consideration is pointed out.
EXTENDED STATE EXPANSIONS AND THE UNIVERSALITY OF WITTEN’S VERSION OF LINK POLYNOMIAL THEORY
Authors: GE MO-LIN , LI YU-QUAN , XUE KANG
Published: November 2004

The Witten’s version for constructing the skein relations of link polynomials based on (2+1) Chern-Simons Lagrangian is shown to be universal for Lie algebras. The extended state calculations are developed to give the explicit representations of braid group and new understanding of framing factor from the point of view of generalized Markov trace.
NEARTHRESHOLD PHENOMENA IN LOW ENERGY ANTIPROTON PHYSICS
Authors: DALKAROV O. D. , PROTASOV K. V. , SHAPIRO I. S.
Published: November 2004

The experimental data on low energy [Formula: see text] elastic scattering and annihilation, and on the [Formula: see text] reaction near threshold are well-described in the framework of a simple unitary coupled channel model. Large P-wave enhancement observed in these experiments is shown to be a result of the existence of the nearthreshold bound and resonant P-states of quasinuclear nature in baryon-antibaryon systems. Other possible manifestations of such [Formula: see text] states in the experiments with low energy antiprotons are considered.
BRAIDS, LINK POLYNOMIALS AND TRANSFORMATIONS OF SOLVABLE MODELS
Authors: DEGUCHI TETSUO
Published: November 2004

It is shown that braid matrices and link polynomials can be systematically constructed from exactly solvable models in statistical mechanics. Through symmetry breaking transformations, different braid matrices are derived from a solvable model. By associating the Markov traces with multi-variable representations, multi-variable link polynomials are obtained. Infinitesimal operators for braid matrices are constructed. Connection of our approach to the conformal field theories and the topological quantum field theory is discussed.
THE NATURE OF THE NEUTRAL SUPERSYMMETRIC FERMIONS IN e+e−-COLLISIONS
Authors: CHRISTOVA E. C. , NEDELCHEVA N. P.
Published: November 2004

Annihilation of arbitrarily polarized e+e− into two neutralinos is considered in the framework of the minimal supersymmetric model. It is shown that measurements of the cross section and the spin asymmetries may distinguish between the following three schemes of neutralino mixing: one of the neutralinos is of higgsino type, of gaugino type, or is some general mixture of both higgsino and gaugino components. No assumptions about the other produced neutralino are made. If one of the neutralinos is the lightest SUSY particle, information about its type can be obtained.
NEW UNITARY AFFINE-VIRASORO CONSTRUCTIONS
Authors: HALPERN M. B. , KIRITSIS E. , OBERS N. A. , PORRATI M. , YAMRON JONATHAN P.
Published: November 2004

We report a quasi-systematic investigation of the Virasoro master equation. The space of all affine-Virasoro constructions is organized by K-conjugation into affine-Virasoro nests, and an estimate of the dimension of the space shows that most solutions await discovery. With consistent ansätze for the master equation, large classes of new unitary nests are constructed, including 1) quadratic deformation nests with continuous conformal weights, and 2) unitary irrational central charge nests, which may dominate unitary rational central charge on compact g.
ACTION AT A DISTANCE AND STRAIGHT-LINE STRING
Authors: PRON'KO G. P.
Published: November 2004

Two massless scalar particles interacting via "gluonic" vector field with a propagator 1/k4 are shown to behave like the ends of a straight-line relativistic string.
AXIGLUON SIGNALS AT e+e− COLLIDERS
Authors: NOVAES S.F. , RAYCHAUDHURI AMITAVA
Published: November 2004

A massive gauge boson—the axigluon—is predicted in theories with chiral color. If it is not very heavy then it may be possible to produce the axigluon at the upcoming e+e− accelerators. We examine the detectability of a quark, antiquark, axigluon final state through an analysis of the thrust distributions.
ZERO ENERGY GAUGE FIELDS AND THE PHASES OF A GAUGE THEORY
Authors: GUENDELMAN E.I.
Published: November 2004

A new approach to the definition of the phases of a Poincare invariant gauge theory is developed. It is based on the role of gauge transformations that change the asymptotic value of the gauge fields from zero to a constant. In the context of theories without Higgs fields, this symmetry can be spontaneously broken when the gauge fields are massless particles, explicitly broken when the gauge fields develop a mass. Finally, the vacuum can be invariant under this transformation, this last case can be achieved when the theory has a violent infrared behavior, which in some theories can be connected to a confinement mechanism.
LEVEL STRUCTURE AND REFLECTION ASYMMETRIC SHAPE IN 223Ac
Authors: SHELINE R.K. , LIANG C.F. , PARIS P.
Published: November 2004

Mass separated sources of 227 Pa (separated as [Formula: see text] ions) were used to study the level structure of 223Ac following alpha decay. The levels in 223 Ac are interpreted as K=5/2± and K=3/2± parity doublet bands which occur naturally in reflection asymmetric models and the multiphonon octupole model. The anomalous structure of the K=3/2− band is explained in terms of Coriolis coupling. The low lying parity doublet bands in 223 Ac , 225 Ac , and 227 Ac are compared and contrasted.
THE LEVEL STRUCTURE, SPINS AND PARITIES OF 223Ac
Authors: SHELINE RAYMOND K. , SOOD PRAKASH C. , LIANG C.F. , PARIS P. , HOFF RICHARD W.
Published: November 2004

The spin-parity assignments of 223 Ac are discussed based on a critical reexamination of the experimental data and the theoretical calculations.
PATH-INTEGRAL BOSONIZATION IN A TOPOLOGICAL BACKGROUND: THE THIRRING MODEL
Authors: MANÍAS M.V. , NAÓN C.M. , TROBO M.L.
Published: November 2004

We investigate the Thirring model in a nontrivial topological sector through the path-integral approach to bosonization. In particular we analyze the minimal correlation functions of the kind studied in a recent work by Bardakci and Crescimanno (B.C.).1 We find that there exist no nonvanishing minimal functions for any finite value of the Thirring coupling constant g2. For g2→∞ we recover the results of B.C.
AN UPPER LIMIT TO QUASAR’S PECULIAR VELOCITY
Authors: FANG L.Z. , CHU Y.Q. , ZHU X.F. , WANG L.F.
Published: November 2004

The peculiar velocity of quasars is among the most sought data of observational cosmology. This paper discusses a method of determining an upper limit to the peculiar velocity of quasars by means of a statistical analysis on quasar pairs. A preliminary conclusion is that the peculiar velocity in the direction along the line joining the two quasars in a pair may not exceed, on average, one thousand km/sec.
FLUX-BREAKING OF SECOND E8 IN THREE-GENERATION SUPERSTRING MODELS
Authors: ANANTHANARAYAN B.
Published: November 2004

Some Calabi-Yau manifolds leading to three generations of chiral fermions in the heterotic E8×E8 some superstring theory are endowed with a freely acting discrete symmetry Z3, which when mapped homomorphically into the E6 subgroup of the first E8 causes it to break to ( SU (3))3 or SU(6)×U(1). The same discrete group can be mapped homomorphically into the second E8 and can result in its breaking. We obtain some of the maximal subgroups of E8 and present the breaking directions in weight space for some breakings. Flux-tubes arise in these theories and their significance in cosmology is briefly discussed.
SUPERSYMMETRIC QUANTUM MECHANICS, COUPLED CHANNELS, SCATTERING RELATIONS
Authors: AMADO R.D. , CANNATA F. , DEDONDER J.P.
Published: November 2004

We study supersymmetric quantum mechanics with particular emphasis on scattering relations and coupled channels. We discuss channels with different masses, the threshold behavior of supersymmetric S-matrix partners, phase equivalence, and the appearance and disappearance of S-matrix poles. We also present some soluble examples.
P, T AND THE COSMOLOGICAL CONSTANT
Authors: BENGTSSON INGEMAR
Published: November 2004

Parity inversion P and time reversal T are studied, in a coordinate dependent way, for Einstein’s theory of gravity written in terms of spatial triads. We point out that the content of these operations may be changed by field redefinitions that change the tensor density weight of the triad. We define new operations P and T, having no counterpart for conventional weight assignments, which transform the Lagrangian density in the expected way if and only if the cosmological constant is zero. However, important matter couplings also “misbehave” under these new operations. We are unable to show that the “old” operations P and T leave the action invariant, if one uses Ashtekar’s variables, and extends the phase space to include degenerate triads.
ASYMPTOTIC BEHAVIOUR OF THE VACUUM ENERGY FOR SMALL SKYRMIONS
Authors: ZUK JOSEF A.
Published: November 2004

Various schemes for deriving effective Lagrangians, involving both quark and meson degrees of freedom, which are intermediate between QCD and low-energy pion dynamics have been proposed. While integration over the fermion fields within the framework of renormalized field theory leads to a vacuum instability, physically reasonable results are obtained for the theory taken with finite cut-off. In principle, properties of the nucleon, such as its mass, can be obtained from a self-consistent calculation in the Skyrmion sector. This procedure can be simplified by implementing an analytical approximation for the fermion vacuum energy which plays a central role. We discuss such an approximation, and use it to calculate exactly the asymptotic behaviour of the vacuum energy for small Skyrmions. It is found that, unlike in the renormalized theory, its functional dependence on the Skymion radius in this limit depends on the characteristics of the Skyrmion profile and choice of regularization scheme; however, the cut-off field theory exhibits no vacuum instability.
HAMILTONIAN REDUCTION OF FIRST-ORDER ACTIONS
Authors: GOVAERTS JAN
Published: November 2004

The Hamiltonian structure associated to an arbitrary system described by a first-order action is considered in detail. The equivalence of two possible approaches is established in full generality. The first has been advocated recently by Faddeev and Jackiw. The second is based on the more standard methods of constrained dynamics. Some consequences of the general analysis are also discussed.
INTERACTION BETWEEN COLOUR-SINGLET HADRONS FROM NONPERTURBATIVE QCD
Authors: WARNER ROLAND C. , JOSHI G.C.
Published: November 2004

We present a nonperturbative QCD contribution to interactions between separated coloursinglet hadrons, arising from the nontrivial topology of the QCD vacuum. We have calculated the effect of the structure of the vacuum (modelled here as a dilute gas of instantons) on hadron propagation, as a way of studying at least some nonperturbative effects. We find that a nonperturbative interaction arises which is familiar to us from our earlier studies of many-body potentials in multiquark systems. This interaction is distinct from those earlier perturbative QCD calculations which bear a direct analogy to the van der Waals interaction of atomic physics.
GAUGINO CONDENSATION AND SUPERSYMMETRY BREAKDOWN
Authors: NILLES HANS PETER
Published: November 2004

We review the status of dynamical supersymmetry breakdown through the mechanism of gaugino condensation. As in the case of hidden-sector supergravity models, such a process seems to be particularly attractive in the framework of effective Lagrangians that describe the low-energy behaviour of string theories.
GAUGE DEFORMATIONS OF CONFORMAL FIELD THEORIES AND ZAMOLODCHIKOV'S C-FUNCTION
Authors: YAMAGUCHI MASAHIRO
Published: November 2004

We study the deformations of conformal field theories in which the perturbing fields include the Virasoro secondary fields of the form L−1φ. We introduce the notion of gauge deformation which is an analogue of the off-shell gauge transformation in string theory. We also calculate Zamolodchikov's c-function and show that it is invariant under the gauge deformation.
MESONS, SKYRMIONS AND BARYONS
Authors: BALL R.D.
Published: November 2004

We review the construction of low energy effective actions for QCD expressed in terms of mesons and baryons rather than quarks and gluons. The mesons consist of quark-antiquark pairs bound by effective gluon exchange, while the baryons contain three valence quarks, also bound by effective gluon exchange, but enveloped in a meson cloud (the “sea quarks”), which may take the form of a chiral soliton. Such a “chiral quark soliton model” offers a unified approach to the various superficially dissimilar models of baryons currently popular, in particular constituent quark models, chiral bags, and Skyrmions, permitting an objective assessment of which is likely to be the most useful for a given physical problem.
NEW EXPERIMENTAL RESULTS FOR INTERMEDIATE- AND HIGH-ENERGY POLARIZATION ASYMMETRY
Authors: YOKOSAWA AKIHIKO
Published: November 2004

We review recent experimental data on polarization asymmetry at intermediate and high energies. We include phenomenological interpretations of the data.

In this review we examine the present status of polarization physics at intermediate and high energies. Special attention is directed to controversial experimental results as well as interpretations of the data. Our objective is to contribute toward the planning of future experimental facilities and experiments. For more detailed description and discussion of various experiments and phenomenological interpretations, we provide extensive references.

Polarized-beam programs at the SLC (Stanford Linear Collider), HERA (Hadron Electron Ring Accelerator, and EPC (Electron Positron Collider) are not included in this review. Neither do we discuss the technologies of polarized ion sources, polarized targets, polarized beams, or accelerators.
TOPOLOGICAL ORDERS IN RIGID STATES
Authors: WEN X. G.
Published: November 2004

We study a new kind of ordering — topological order — in rigid states (the states with no local gapless excitations). We concentrate on characterization of the different topological orders. As an example we discuss in detail chiral spin states of 2 + 1 dimensional spin systems. Chiral spin states are described by the topological Chern-Simons theories in the continuum limit. We show that the topological orders can be characterized by a non-Abelian gauge structure over the moduli space which parametrizes a family of the model Hamiltonians supporting topologically ordered ground states. In 2 + 1 dimensions, the non-Abelian gauge structure determines possible fractional statistics of the quasi-particle excitations over the topologically ordered ground states. The dynamics of the low lying global excitations is shown to be independent of random spatial dependent perturbations. The ground state degeneracy and the non-Abelian gauge structures discussed in this paper are very robust, even against those perturbations that break translation symmetry. We also discuss the symmetry properties of the degenerate ground states of chiral spin states. We find that some degenerate ground states of chiral spin states on torus carry non-trivial quantum numbers of the 90° rotation.
SIMPLE GEOMETRICAL INTERPRETATIONS OF QUASI-PERIODIC POINT SETS BY VARIOUS CONCEPTS OF INTERPENETRATION
Authors: CODDENS G.
Published: November 2004

Behind several methods to describe quasicrystals there is some concept of interpenetration. Two such concepts are outlined in this paper, giving a geometrically attractive interpretation of quasi-periodic (QP) point sets.

First we show how QP tilings constructed with the grid method can also be obtained by taking the mass centre of suitably chosen sets of points belonging to a union of periodic lattices (intertwinning).

In a second part of the paper it is shown how from the projection method QP point sets can be obtained that can be decomposed into a superposition of distorted lattices (intergrowth1). These decompositions are derived for the case where a face-centered hypercubic Bravais lattice generates the pattern. A general study of such decompositions may be of heuristic value for structure determinations.
PATTERN FORMATION IN CONVECTIVE INSTABILITIES
Authors: FRIEDRICH R. , BESTEHORN M. , HAKEN H.
Published: November 2004

The present article reviews recent progress in the study of pattern formation in convective instabilities. After a brief discussion of the relevant basic hydrodynamic equations as well as a short outline of the mathematical treatment of pattern formation in complex systems the self-organization of spatial and spatio-temporal structures due to convective instabilities is considered. The formation of various forms of convective patterns arising in the Bénard experiment, i.e. in a horizontal fluid layer heated from below, is discussed. Then the review considers pattern formation in the Bénard instability in spherical geometries. In that case it can be demonstrated how the interaction among several convective cells may lead to time dependent as well as chaotic evolution of the spatial structures. Finally, the convective instability in a binary fluid mixture is discussed. In contrast to the instability in a single component fluid the instability may be oscillatory. In that case convection sets in in the form of travelling wave patterns which in addition to a complicated and chaotic temporal behaviour exhibit more or less spatial irregularity already close to threshold.
WHY DOES HIGH Tc SOMETIMES DEPEND ON OXIDATION — AN INVESTIGATION OF MADELUNG POTENTIALS
Authors: TAN N. X. , BOURDILLON A. J.
Published: November 2004

Some high temperature superconductors require atmospheres of oxygen for the formation of the superconducting phase, and others do not. The former corrode more easily and includes the doped compound ( La 1.5 Ba 0.5) CuO 4. In the latter class, Cu ions inhabit sites with large ionic potential, which apparently allows the formation of high charge states such as Cu (d8) or CuO +. An elementary code was used to examine potentials on a number of defect sites. Thus a high charge state on polyvalent Cu is a feature common to both types of superconductors.
LOW TEMPERATURE ACTION FOR QUANTUM ANTIFERROMAGNETS ON A TRIANGULAR LATTICE
Authors: ANGELUCCI ANTIMO
Published: November 2004

We present the long-wavelengths/low-frequencies action of a two-dimensional quantum Heisenberg antiferromagnet of general spin magnitude s on a triangular lattice which describe the fluctuations around the ordered Neél ground state. This action is a nonlinear σ-model whose configuration space is the SO(3) manifold, in this respect being different from the usual S2 σ-model which models an antiferromagnet on a bipartite lattice. We present a map on a O(4)-model which allows to study the properties of the system.