Complete structure of Z_n Yukawa couplings

We give the complete twisted Yukawa couplings for all the Z_n orbifold constructions in the most general case, i.e. when orbifold deformations are considered. This includes a certain number of tasks. Namely, determination of the allowed couplings, calculation of the explicit dependence of the Yukawa couplings values on the moduli expectation values (i.e. the parameters determining the size and shape of the compactified space), etc. The final expressions are completely explicit, which allows a counting of the DIFFERENT Yukawa couplings for each orbifold (with and without deformations). This knowledge is crucial to determine the phenomenological viability of the different schemes, since it is directly related to the fermion mass hierarchy. Other facts concerning the phenomenological profile of Z_n orbifolds are also discussed, e.g. the existence of non--diagonal entries in the fermion mass matrices, which is related to a non--trivial structure of the Kobayashi--Maskawa matrix. Finally some theoretical results are given, e.g. the no--participation of (1,2) moduli in twisted Yukawa couplings. Likewise, (1,1) moduli associated with fixed tori which are involved in the Yukawa coupling, do not affect the value of the coupling.Comment: 60 page

A modular radiative transfer program for gas filter correlation radiometry

The fundamentals of a computer program, simulated monochromatic atmospheric radiative transfer (SMART), which calculates atmospheric path transmission, solar radiation, and thermal radiation in the 4.6 micrometer spectral region, are described. A brief outline of atmospheric absorption properties and line by line transmission calculations is explained in conjunction with an outline of the SMART computational procedures. Program flexibility is demonstrated by simulating the response of a gas filter correlation radiometer as one example of an atmospheric infrared sensor. Program limitations, input data requirements, program listing, and comparison of SMART transmission calculations are presented

Data reduction analysis and application technique development for atmospheric trace gas constituents derived from remote sensors on satellite or airborne platforms

The applicability of the gas filter correlation radiometer (GFCR) to the measurement of tropospheric carbon monoxide gas was investigated. An assessment of the GFRC measurement system to a regional measurement program was conducted through extensive aircraft flight-testing of several versions of the GFRC. Investigative work in the following areas is described: flight test planning and coordination, acquisition of verifying CO measurements, determination and acquisition of supporting meteorological data requirements, and development of supporting computational software

SUSY Soft Breaking Terms from String Scenarios

The general SUSY soft breaking terms for a large class of phenomenologically relevant string scenarios (symmetric orbifolds) are given. They show a certain lack of universality, but not dangerous for flavor changing neutral currents. To get more quantitative results a specific SUSY breaking mechanism has to be considered, namely gaugino condensation in the hidden sector. Then, it turns out that squark and slepton masses tend to be much larger than scalar masses ($m_{\phi} > 10 M_a$), which probably is a quite general fact. Experimental bounds and the requirement of a successful electroweak breaking without fine tuning impose further restrictions on the soft breaking terms. As a consequence the gluino and chargino masses should be quite close to their present experimental limits, whereas squark and slepton masses should be much higher (> 1 TeV).Comment: (Talk presented at the SUSY-93 Conference, Boston, March 29 - April 2, 1993), 11 pages, CERN--TH.6922/9

Entanglement and the Quantum Brachistochrone Problem

Entanglement is closely related to some fundamental features of the dynamics of composite quantum systems: quantum entanglement enhances the "speed" of evolution of certain quantum states, as measured by the time required to reach an orthogonal state. The concept of "speed" of quantum evolution constitutes an important ingredient in any attempt to determine the fundamental limits that basic physical laws impose on how fast a physical system can process or transmit information. Here we explore the relationship between entanglement and the speed of quantum evolution in the context of the quantum brachistochrone problem. Given an initial and a final state of a composite system we consider the amount of entanglement associated with the brachistochrone evolution between those states, showing that entanglement is an essential resource to achieve the alluded time-optimal quantum evolution.Comment: 6 pages, 3 figures. Corrected typos in Eqs. 1 and

Constraint-preserving boundary conditions in the 3+1 first-order approach

A set of energy-momentum constraint-preserving boundary conditions is proposed for the first-order Z4 case. The stability of a simple numerical implementation is tested in the linear regime (robust stability test), both with the standard corner and vertex treatment and with a modified finite-differences stencil for boundary points which avoids corners and vertices even in cartesian-like grids. Moreover, the proposed boundary conditions are tested in a strong field scenario, the Gowdy waves metric, showing the expected rate of convergence. The accumulated amount of energy-momentum constraint violations is similar or even smaller than the one generated by either periodic or reflection conditions, which are exact in the Gowdy waves case. As a side theoretical result, a new symmetrizer is explicitly given, which extends the parametric domain of symmetric hyperbolicity for the Z4 formalism. The application of these results to first-order BSSN-like formalisms is also considered.Comment: Revised version, with conclusive numerical evidence. 23 pages, 12 figure

How influential is ballot design in elections?

We exploit an original dataset from a referendum in Peru to study the influence of voting "arrangements" on electoral outcomes. The relative importance of these arrangements (e.g., ballot design) with respect to the fundamentals (e.g., ideology, candidates' quality) has not been measured. After controlling for a comprehensive set of politicians' characteristics, we estimate unbiased ballot order effects making use of the within party variation in outcomes. We estimate a non-linear probability model and we create counterfactuals to conclude that ballot design not only may have changed the electoral results but also has a greater importance than candidates' ideology, education, experience and party affiliation

Three field tests of a gas filter correlation radiometer

Test flights to remotely measure nonurban carbon monoxide (CO) concentrations by gas filter correlation radiometry are discussed. The inferred CO concentrations obtained through use of the Gas Filter Correlation Radiometer (GFCR) agreed with independent measurements obtained by gas chromatography air sample bottle analysis to within 20 percent. The equipment flown on board the aircraft, the flight test procedure, the gas chromatograph direct air sampling procedure, and the GFCR data analysis procedure are reported

Instrumentation status of the low-b magnet systems at the Large Hadron Collider (LHC)

The low-beta magnet systems are located in the Large Hadron Collider (LHC) insertion regions around the four interaction points. They are the key elements in the beams focusing/defocusing process allowing proton collisions at luminosity up to 10**34/cm**2s. Those systems are a contribution of the US-LHC Accelerator project. The systems are mainly composed of the quadrupole magnets (triplets), the separation dipoles and their respective electrical feed-boxes (DFBX). The low-beta magnet systems operate in an environment of extreme radiation, high gradient magnetic field and high heat load to the cryogenic system due to the beam dynamic effect. Due to the severe environment, the robustness of the diagnostics is primordial for the operation of the triplets. The hardware commissioning phase of the LHC was completed in February 2010. In the sake of a safer and more user-friendly operation, several consolidations and instrumentation modifications were implemented during this commissioning phase. This paper presents the instrumentation used to optimize the engineering process and operation of the final focusing/defocusing quadrupole magnets for the first years of operation.Comment: 6 pp. ICEC 23 - ICMC 2010 International Cryogenic Engineering Conference 23 - International Cryogenic Materials Conference 2010. 19-23 Jul 2010. Wroclaw, Polan

Natural history and morphometry of the Cuban iguana (Cyclura nubila Gray, 1831) in Cayo Sijú, Cuba

The report presents data about the Cuban iguana population (Cyclura nubila nubila) inhabiting Cayo Sijú, an 88 ha island off the southwest coast of Cuba. Population densities estimated using strip transects were higher in xerophytic coastal scrub (6.72 ± 6.25 iguanas/ha) than in typical sand vegetation (3.63 ± 2.71 iguanas/ha) and mangrove forests (2.9 ± 2.9 iguanas/ha). The total population for the cay was estimated at 350 individuals with an adult biomass of approximately 11.67 kg/ha. Densities varied minimally between three habitat types and between the wet and dry seasons. No significant density fluctuations were found one month after Hurricane Ivan affected the cay. Iguana burrows were encountered most frequently in beach dunes. Analysis of 30 scat samples revealed eight species of plants, with the fruits of Chrysobalanum icaco and the leaves of Batis maritima being the most frequently identified items. The remains of crab (Cardisoma guandhumi) and insects of the order Hemiptera were also present in scat samples. Sexual dimorphism was evident in this population, with males being significantly larger in eight morphological variables. The snout-vent length measurements were larger in this population than in those reported in two cays off the south coast of Cuba