Low Energy Constants from Kl4 Form-Factors

We have calculated the form-factors F and G in K ---> pi pi e nu decays (Kl4) to two-loop order in Chiral Perturbation Theory (ChPT). Combining this together with earlier two-loop calculations an updated set of values for the L's, the ChPT constants at p^4, is obtained. We discuss the uncertainties in the determination and the changes compared to previous estimates.Comment: 6 pages, uses axodraw.sty, 2 figures, bug in program corrected, new numerical result

The scholarship assignment problem

There are n graduate students and n faculty members. Each student will be assigned a scholarship by the joint faculty. The socially optimal outcome is that the best student should get the most prestigious scholarship, the second-best student should get the second most prestigious scholarship, and so on. The socially optimal outcome is common knowledge among all faculty members. Each professor wants one particular student to get the most prestigious scholarship and wants the remaining scholarships to be assigned according to the socially optimal outcome. We consider the problem of finding a mechanism such that in equilibrium, all scholarships are assigned according to the socially optimal outcome.Publicad

Chiral extrapolation and determination of low-energy constants from lattice data

We propose analytic approximations of chiral SU(3) amplitudes for the extrapolation of lattice data to the physical meson masses. The method allows the determination of NNLO low-energy constants in a controllable fashion. We test the approach with recent lattice data for the ratio F_K/F_pi of meson decay constants.Comment: 10 pages, 1 figure, matches version published in PLB: title enlarged, comments added, results unchange

The closed primaries versus the top-two primary

The top-two primary recently approved in states like Washington, California, and Alaska eliminates the closed party primaries and creates instead a single ballot in which the first and second place winners pass to the general election. We compare the electoral consequences of the top-two primary with those of the closed primaries. We present a model where each primary procedure induce a sequential game with three stages: candidate-entry stage, primary election, and general election. We analyze the equilibria of these games and show that the top-two primary contributes to political moderation and may increase the number of swing states.Financial assistance from Ministerio de Ciencia e Innovación under project ECO2011-29355 and Junta de Andalucía under project SEJ5980 is gratefully acknowledged

Kℓ4K_{\ell 4} Form-Factors and π\pi-π\pi Scattering

The $F$ and $G$ form-factors of $K_{\ell4}$ and the quark condensates are calculated to ${\cal O}(p^6)$ in Chiral Perturbation Theory (CHPT). Full formulas are presented as much as possible. A full refit of most of the ${\cal O}(p^4)$ CHPT parameters is done with a discussion of all inputs and underlying assumptions. We discuss the consequences for the vacuum expectation values, decay constants, pseudoscalar masses and $\pi$-$\pi$ scattering.Comment: 51 page

Relations at Order p6p^6 in Chiral Perturbation Theory

We report on a search of relations valid at order $p^6$ in Chiral Perturbation Theory. We have found relations between $\pi\pi$, $\pi K$ scattering, $K_{\ell4}$ decays, masses and decay constants and scalar and vector form factors. In this paper we give the relations and a first numerical check of them.Comment: 18 pages, numerical discussion extended including a new figur

Improving the Hadronization of QCD currents in TAUOLA and PHOKHARA

We present our study of the hadronization structure of both vector and axial-vector currents leading to decays of the tau into two kaons and a pion. The cornerstones of our framework are the large-N_C limit of QCD, the chiral structure exhibited at low energies and the proper asymptotic behaviour, ruled by QCD, that is demanded to the associated form factors. The couplings of the theory are mostly constrained by this procedure and upon the analysis of BaBar data on e^+e^- -> KK pi we are able to predict the hadronic spectra.Comment: 4 pages, 1 figure. To appear in the Proceedings of QCD 08: 14th International QCD Conference, 7-12th July 2008 Montpellier (France). To be published by Elsevier in Nuclear Physics B (Proceedings Supplement

The SU(2) and SU(3) chiral phase transitions within Chiral Perturbation Theory

The SU(2) and SU(3) chiral phase transitions in a hot gas made of pions, kaons and etas are studied within the framework of Chiral Perturbation Theory. By using the meson meson scattering phase shifts in a second order virial expansion, we are able to describe the temperature dependence of the quark condensates. We have estimated the critical temperatures where the different condensates melt. In particular, the SU(3) formalism yields a lower critical temperature for the non-strange condensates than within SU(2), and also suggests that the strange condensate may melt at a somewhat higher temperature, due to the different strange and non-strange quark masses.Comment: 4 pages, two figures. Final version to appear in Phys Rev D. Complete model independent calculation. Unitarized ChPt only used to check extrapolation at high T. References added and numerical bug correcte

Fastest non-ionic azo dyes and transfer of their thermal isomerisation kinetics into liquid-crystalline materials

Push-pull bithienylpyrrole-based azo dyes exhibit thermal isomerisation rates as fast as 1.4 μs in acetonitrile at 298 K becoming, thus, the fastest neutral azo dyes reported so far. These remarkably low relaxation times can be transferred into liquid-crystalline matrixes enabling light-triggered oscillations in the optical density of the final material up to 11 kHz under ambient conditions.Financial support for this research was obtained from the Ministerio de Economía y Competitividad (Spain, CTQ2012-36074 and CTQ2015-65770-P). The authors thank Prof. Santi Nonell for his help with the flash photolysis measurements. Thanks are also due to: Fundação para a Ciência e Tecnologia (FCT) for a PhD grant to M. C. R. Castro (SFRH/BD/78037/2011); FEDERCOMPETE for financial support through the Centro de Quı ´mica – UM, PEst-C/QUI/UI0686/2013 (FCOMP-01-0124-FEDER-037302). The NMR spectrometer Bruker Avance III 400 is part of the National NMR Network and was purchased within the framework of the National Program for Scientific Re-equipment, contract REDE/1517/RMN/2005 with funds from POCI 2010 (FEDER) and FCT

Acercamiento a los sistemas de gestión de contenidos. Campus Mare Nostrum

[SPA]Con el objetivo de describir y analizar un gestor de contenidos ad hoc se utiliza el CMS (Computer Management System) del Campus de Excelencia Mare Nostrum (CMN de aquí en adelante). El CMS del CMN pertenece a la Universidad de Murcia y la Universidad Politécnica de Cartagena (España). Para ello, inicialmente se hace una revisión teórica sobre lo que es un CMS. En un segundo momento, se exponen modelos de CMS actuales como acercamiento al concepto de sistema de gestión de contenidos o CMS. Finalmente, se ofrece una introducción al CMN como entorno de trabajo para concluir incidiendo en la importancia de la visibilidad web. [ENG]In order to describe and analyze a Content Management System ad hoc (CMS), we will use the web of Campus de Excelencia Mare Nostrum (CMN). This CMS of the CMN is inside at the University of Murcia and Politechnic University of Cartagena (Spain). First of all, we offer a theoretical review over what it is a Content Management System. In a second time, we present CMS current models as an approach to the concept of CMS. Finally, we offer an aproach about CMN as well, to conclude taking note about the web visibility at the WWW.Campus Mare Nostrum, Universidad Politécnica de Cartagena, Universidad de Murcia, Región de Murci