Reaction symmetries for multiplet production

A theorem concerning nuclear reaction symmetries for isospin multiplet production involving complex nuclei is proved and generalized. The general formalism of possible symmetry violations is presented. Elastic scattering, multiparticle production in the final state, symmetry relations for polarizations, and substructure symmetries are discussed within the framework of the theorem. It is shown that the theorem has an extension in the case of multiplet production involving elementary particles. It is studied briefly in the case of SU(3) and SU(n) multiplets. Finally, some general remarks are made about approximate symmetries for multiplet production.     

Some phenomenological consequences of the super higgs effect

To the combined system of supergravity ofN=1 and the Higgs multiplet (a scalar multiplet) is coupled a complex scalar multiplet as a simplified representative of the matter. An order-of-magnitude estimate is attempted on the masses and the couplings of the gravitino and other fields.     

Wavelength coincidence of allowed and intercombination multiplets in N III and O IV: A density and/or temperature diagnostic

Two multiplets of N III with different intensity dependence on source conditions fall in the same wavelength interval near 1750 Å, and the analogous multiplets in O IV also lie close together. It is suggested that the multiplet pair can be useful for diagnostic purposes. The calculated ratios are consistent with available observations. A preliminary inspection of solar flare spectra shows the presence of the higher-density-indicating allowed multiplet in O IV.     

Matter coupling and non-linear σ-models in N = 2 supergravity

Starting from an off-shell formulation of N = 2 supergravity, we construct the matter multiplet in its complex form (the scalar hypermultiplet) and in its real form. We construct the matter action which describes the coupling to supergravity. The interpretation where the 32 + 32 field components of the minimal gravitational multiplet are independent dynamical variables is known to be inconsistent for pure supergravity. We find it to be consistent when coupled to at least one matter multiplet, and to give rise to supersymmetric σ-models when coupled to at least two matter multiplets.     

Effective lagrangian for spontaneously broken N = 2 superconformal symmetry

In a general framework of non-linear realizations for space-time symmetries, we investigate the effective lagrangian for N = 2 superconformal symmetry which is spontaneously broken down to N = 2 super-Poincaré symmetry. For the case in which the dilation multiplet is a massless N = 2 gauge multiplet, we derive a low-energy effective lagrangian which describes the interaction of Nambu-Goldstone particles.     

Semi-leptonic decays in the model of Bars,Halpern, and Yoshimura

Semi-leptonic decays are investigated in the gauge theory of Bars, Halpern and Yo Yoshimura, using elementary baryons rather than quarks. It is proved that in order to get a correct d/f ratio in these decays it is necessary to use an (8,8) spin-zero hadron field, together with another multiplet of spin-zero hadrons. The tree approximation is shown not to be sufficient to calculate the decay amplitudes correctly.     

The improved tensor multiplet in N = 2 supergravity

We construct a scale-invariant action for the N = 2 tensor multiplet which can be coupled to conformal supergravity. In spite of its non-polynomial form the action describes a free massless hypermultiplet. When used as a compensating multiplet it leads to a new minimal formulation of N = 2 Poincaré or de Sitter supergravity. We discuss its consequences and present a comparison with previous off-shell formulations.     

On renormalizability of non-anticommutativeN=(1, 0) theories with singlet deformation

We study the quantum properties of two theories with a non-anticommutative chiral singlet deformation ofN=(1, 1) supersymmetry: the Abelian model of a vector gauge multiplet and the model of a gauge multiplet interacting with a neutral hypermultiplet. Both these models are proved to be not only renormalizable but also finite.     

An off-shell superspace R2-action in six dimensions

The superspace constraints corresponding to the two inequivalent versions of the 40 + 40 off-shell Weyl multiplet in six dimensions are given. A supersymmetric R²-action (including quartic fermion terms) for one of the two Weyl multiplets is constructed. A crucial role in this construction is played by the observation that there exists a formal relationship between the Weyl and Yang-Mills multiplets. Both the supersymmetric R²-action and the supersymmetric Yang-Mills F²-action coupled to the Weyl multiplet are reformulated as superspace actions.     

Compactification of d = 11 supergravity on S4 (or 11 = 7 + 4, too)

Eleven-dimensional supergravity can compactify spontaneously on either S⁷ or S⁴. We study the latter case, with attention to its connection with a possible gauged N = 4 supergravity in d = 7. We derive the linearized field equations and supersymmetry transformation rules for the effective d = 7 supergravity multiplet. There are five third rank antisymmetric tensors in this multiplet which are in the 5 representation of the gauge group USp(4) and they are propagated with a self-duality condition in 7 dimensions. There is also a 14 of scalar fields and they are found to propagate with a non-conformal wave operator.     

Massless spectrum and critical dimension of the supermembrane

We show the existence of massless particles in the supermembrane. These occur in the sector of a completely collapsed membrane and receive zero vacuum energy thanks to supersymmetry. Only in the 11-dimensional supermembrane the massless states include a graviton. Thus, in the critical dimension d = 11 the massless particles correspond to the supergravity multiplet. We also find that higher extended objects beyond the supermembrane have no critical dimension in which the supergravity multiplet emerges.     

Group manifold first-order formulation of N=2, d=4 supergravity theory

In this paper, the so far lacking first-order formulation of N = 2 supergravity is obtained in the group manifold rheonomic symmetry approach. In order for the theory to be non-trivial it must contain, besides the pseudoconnection, also a 0-form matter multiplet which, moreover, provides the mechanism to generate the spin-l field kinetic term. It is explicitly shown how the O(2)～U(1) symmetry is realized not by a linear gauge transformation, rather by a rheonomic one.     

Low-spin excitations in 146Sm

The low-spin excitations of the nucleus ¹⁴⁶Sm which is just two neutrons and two protons away from the N = 82 shell and Z = 64 subshell closures have been investigated by means of the ¹⁴³Nd (??, n) and ¹⁴⁴Nd (??, 2n) fusion-evaporation reactions. We established 47 hitherto unknown energy levels up to 4.7MeV and 75 new transitions. In addition, 7 spin assignments were possible from the ??-?? angular correlation analysis. The structure of the possible candidates for a 2⁺ ? 3^? quadrupole-octupole multiplet are first discussed in terms of the harmonic vibrational model. A comparison of these states with the corresponding ones in the neighboring N = 84 isotones is also presented. Finally, the structure of the ¹⁴⁶Sm nucleus is interpreted in terms of the IBA-spdf model. It is shown that the model is able to reproduce the experimental relative transition strengths of the 2⁺ ? 3^? quadrupole-octupole multiplet and also a series of collective properties such as the proposed double-octupole excitations.     

The heterotic string is a soliton

It is shown that the Type IIA superstring compactified on K3 has a smooth string soliton with the same zero mode structure as the heterotic string compactified on a four-torus, thus providing new evidence for a conjectured exact duality between the two six-dimensional string theories. The chiral worldsheet bosons arise as zero modes of Ramond-Ramond fields of the IIA string theory and live on a signature (20,4) even, self-dual lattice. Stable, finite loops of soliton string provide the charged Ramond-Ramond states necessary for enhanced gauge symmetries at degeneration points of the K3 surface. It is also shown that Type IIB strings toroidally compactified to six dimensions have a multiplet of string solutions with Type II worldsheets.     

On-shell and conformal N = 4 supergravity in superspace

We discuss the superspace geometries which are necessary to describe on-shell O(4) and SU(4) supergravity. The relation of central charge field strengths to physical spin-zero fields is exhibited and a “new” O(4) theory is shown to exist. The version of SU(4) supergravity which uses an antisymmetric tensor gauge field is found to require modifications of ordinary superspace. Finally the Poincaré supergeometry which admits the conformal N = 4 supermultiplet is constructed. It is shown that consistency of the Bianchi identities implies the existence of dimension zero auxiliary fields which are components of a non-linear multiplet.     

Spectral Artifacts Resulting from Multiple-Quantum Coherence Transfers by Spin Decoupling during Acquisition

Off-resonance coherent decoupling of spin X in a heteronuclear SX_N spin system can result in a multiplet with overlapping lines of spin Sand an overall shape similar to that of a doublet. Such lineshape distortions occur if certain multiple-spin coherences are present when the decoupler is switched on. The distortion could cause an apparent change in the multiplicity of an M + 1 multiplet of an SX_NY_M spin system when a selective decoupling of spins X is applied after a polarization transfer from spins X to spin S by INEPT or DEPT. Possibilities for suppressing the distortions are discussed.     

Invisible axion at an intermediate symmetry breaking scale

We suggest that qq?g mesons mat exist as low as 1 GeV in mass. The exotic J^PC=1^?+ multiplet will have distinctive decay modes and perhaps be relatively stable. The bag model spectrum of the lowest lying qq?g multiplet including hyperfine splittings is computed analogously to Jaffe's qq?qq? bag model multiplets. Relevance to light meson phenomenology is discussed.     

Electromagnetic perturbation of isobaric multiplet widths

The manner in which isobaric multiplet decay widths are modified by electromagnetic interaction is studied. Arguments based on lowest-order perturbation theory are given that the widths should be quadratic in T_z, if the multiplet is particle unstable in the absence of electromagnetism, but quartic for stable multiplets. The total widths of experimentally known multiplets are analyzed to determine their algebraic T_z, dependence and both quadratic and non-quadratic cases are found. On the basis of a simple model of the Coulomb energy we then determine the masses of these multiplets in the absence of electromagnetism as well as the masses of the lowest T-allowed decay channels. We find the isobaric multiplet width equation to work in some cases while it has been found to be inconclusive in others; because of these uncertainties as to its correctness or range of applicability, we have constructed a soluble model in which tests may be carried out. To avoid difficulties such as the many-body problem, a non-local separable potential model simple enough to solve explicitly was chosen. Although the model is an oversimplification of the real nuclear situation it has been found to work very well. Namely, the quadratic quartic nature of the widths was borne out in the model.     

Collisional parameters of N2 broadened methane lines in the R9 multiplet of the 2ν3 band. Multispectrum fittings of the overlapping spectral lines

A high-sensitive two-channel photo-acoustic (PA) spectrometer with a near infrared diode laser was used to make precise measurements of N₂-broadened methane spectra in the R9 multiplet of 2ν₃ band. For the accurate retrieval of spectroscopic line parameters (intensities, positions at zero pressure, pressure-shifting and -broadening, collisional narrowing and line mixing coefficients) from the methane PA spectra, a program based on a multispectrum fitting procedure has been used. The multispectrum least squares fitting procedure is based on a relatively simple line profile model and on the linear pressure dependences of the line profile parameters. The line parameters were determined for 11 lines of the methane 2ν₃ R9 multiplet. The results have been compared with other available data.     

The density multiplet in superspace

We calculate the components of the density multipletE inN=1 superspace and the last component of the chiral density multiplet ? inSU(2) extended superspace with a minimal set of auxiliary fields.