We construct explicit examples with a horizontal, ''anomalous'' U͑1͒ gauge group, which, in a supersymmetric extension of the standard model, reproduce qualitative features of the fermion spectrum and CKM matrix, and suppress FCNC and proton decay rates without the imposition of global symmetries. We review the motivation for such ''more'' minimal supersymmetric standard models and their predictions for the sparticle spectrum. There is a mass hierarchy in the scalar sector which is the inverse of the fermion mass hierarchy. We show in detail why ⌬Sϭ2 FCNCs are greatly suppressed when compared with naive estimates for nondegenerate squarks. ͓S0556-2821͑97͒04215-X͔ PACS number͑s͒: 12.60. Jv, 14.80.Ly The minimal supersymmetric standard model ͑MSSM͒ with top-squark-induced electroweak symmetry breaking naturally stabilizes the electroweak scale, but fails to exhibit the accidental global symmetries of the standard model ͑SM͒ which inhibit flavor-changing neutral currents ͑FCNCs͒, lepton flavor violation ͑LFV͒, electric dipole moments ͑EDMs͒, and proton decay. To agree with experimental bounds, such processes must be suppressed by imposing approximate global symmetries to produce degeneracy or alignment in the squark and slepton mass matrices. Recently, Cohen, Kaplan, and Nelson ͓1͔ have proposed an alternative framework in which the gauginos, Higgsinos, and third generation squarks are sufficiently light to naturally stabilize the electroweak scale, while the first two generations of squarks and sleptons are sufficiently heavy to suppress FCNC, LFV, and EDMs below experimental bounds. Such models are ''more'' minimally supersymmetric than the MSSM in the sense that they do not require the ad hoc supposition of degeneracy or alignment. The anomalous U͑1͒ X used by Dvali and Pomarol ͓2͔, and Binetruy and Dudas ͓3͔ ͑DPBD͒ to break supersymmetry could induce the required mass hierarchy, provided third generation matter carries no X charge. In this paper, we show that an anomalous U͑1͒ X can also explain the order of magnitude of fermion masses and mixing angles, and suppress proton decay from dimension-five operators. Our criteria for assigning U͑1͒ X charges differ significantly from those considered previously in this context ͓3,4͔.The DPBD mechanism of supersymmetry breaking requires a gauged U͑1͒ X with positively and negatively X-charged matter superfields P and N. If X symmetry is anomalous ͓i.e., tr(X) 0͔ below some scale M , the effective theory below this scale includes a Fayet-Iliopoulos term ϳg X 2 trXM 2 ͓5͔. For mathematical consistency, one can either imagine that M is the Planck scale and the anomaly is canceled via the Green-Schwarz mechanism ͓6͔, or that M is some other high scale at which anomaly canceling matter lives. If the superpotential also contains a term of the form mPN, introduced either explicitly or dynamically by nonperturbative physics, the various fields obtain vacuum expectation values: 1where ⑀ is given byThe D term vacuum expectation value ͑VEV͒ gives each scalar matter field a mass...

Gauge theories broken by a single Higgs eld are known to have rst-order phase transitions in temperature if =g 2 1, where g is the gauge coupling and the Higgs self-coupling. If the theory is extended from one to N Higgs doublets, with U(N) a v or symmetry, the transition is known to be second order for =g 2 > 1 in the N ! 1 limit. We show that one can in principal compute the tricritical value of =g 2 , separating rst from secondorder transitions, to any order in 1=N. In particular, scalar uctuations at the transition damp away the usual problems with the infrared behavior of high-temperature non-Abelian gauge theories. We explicitly compute the tricritical value of =g 2 for U(1) and SU(2) gauge theory to next-to-leading order in 1=N.

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The University of Canterbury has developed a rocket research group, UC Rocketry, which recently broke the world altitude record for an I-class motor (impulse of 320-640 Ns) and has run a rocketry course for the first time in New Zealand. This paper discusses the development and results of the world record rocket "Milly" and details all the fundamental elements of the rocketry final year engineering course, including the manufacturing processes, wind tunnel testing, avionics, control and the final rocket launch of "Smokey". The rockets Milly and Smokey are an example of the design, implementation and testing methodologies that have significantly contributed to research and graduates for New Zealand's space program.

The positions of quasi Landau resonances as a function of magnetic field strength are reported for the first time. These resonances were observed near the ionization limit in the even-parity channels of barium and strontium with use of two-photon laser spectroscopy" The change in the resonance positions as the field strength is varied and the energy spacings of the resonances agree well with hydrpgenic semiclassical theory. Resonance profiles, but not positions, are found to be species dependento