Identification of a Scalar Glueball

We have performed a coupled channel study of the meson-meson S-waves involving isospins (I) 0, 1/2 and 3/2 up to 2 GeV. For the first time the channels \pi\pi, K\bar{K}, \eta\eta, \sigma\sigma, \eta\eta', \eta'\eta', \rho\rho, \omega\omega, \omega\phi$, \phi\phi, a_1\pi and \pi^*\pi are considered. All the resonances with masses below 2 GeV for I=0 and 1/2 are generated by the approach. We identify the f_0(1710) and a pole at 1.6 GeV, which is an important contribution to the f_0(1500), as glueballs. This is based on an accurate agreement of our results with predictions of lattice QCD and the chiral suppression of the coupling of a scalar glueball to \bar{q}q. Another nearby pole, mainly corresponding to the f_0(1370), is a pure octet state not mixed with the glueball.Comment: 5 pages, 1 figure. More data are included and reproduced. Some discussions have been rephrase

Scalar-Pseudoscalar scattering and pseudoscalar resonances

The interactions between the f_0(980) and a_0(980) scalar resonances and the lightest pseudoscalar mesons are studied. We first obtain the interacting kernels, without including any ad hoc free parameter, because the lightest scalar resonances are dynamically generated. These kernels are unitarized, giving the final amplitudes, which generate pseudoscalar resonances, associated with the K(1460), \pi(1300), \pi(1800), \eta(1475) and X(1835). We also consider the exotic channels with I=3/2 and I^G=1^+ quantum numbers. The former could be also resonant in agreement with a previous prediction.Comment: 3 pages, 2 figures; Contributed oral presentation in (QCHS09) The IX International Conference on Quark Confinement and Hadron Spectrum - Madrid, Spain, 30 Aug 2010 - 03 Sep 201

Nucleon-Nucleon Interactions from Dispersion Relations: Coupled Partial Waves

We consider nucleon-nucleon interactions from chiral effective field theory applying the N/D method. The case of coupled partial waves is now treated, extending Ref. [1] where the uncoupled case was studied. As a result three N/D elastic-like equations have to be solved for every set of three independent partial waves coupled. As in the previous reference the input for this method is the discontinuity along the left-hand cut of the nucleon-nucleon partial wave amplitudes. It can be calculated perturbatively in chiral perturbation theory because it involves only irreducible two-nucleon intermediate states. We apply here our method to the leading order result consisting of one-pion exchange as the source for the discontinuity along the left-hand cut. The linear integral equations for the N/D method must be solved in the presence of L - 1 constraints, with L the orbital angular momentum, in order to satisfy the proper threshold behavior for L>= 2. We dedicate special attention to satisfy the requirements of unitarity in coupled channels. We also focus on the specific issue of the deuteron pole position in the 3S1-3D1 scattering. Our final amplitudes are based on dispersion relations and chiral effective field theory, being independent of any explicit regulator. They are amenable to a systematic improvement order by order in the chiral expansion.Comment: 11 pages. Extends the work of uncoupled partial waves of M. Albaladejo and J. A. Oller, Phys. Rev. C 84, 054009 (2011) to the case of coupled partial waves. This version matches the published version. Discussion about the deuteron enlarged. Some references adde

Dimensão tradutológica da História natural e moral das Índias

La Historia natural y moral de las Indias, publicada en Sevilla en 1590, es la obra más célebre del Padre José de Acosta (1540-1600) y uno de los textos más importantes de la literatura misionera. La excepcional calidad de este escrito explica la gran difusión de la que ha gozado gracias a las numerosas reediciones y traducciones. No sólo supone una riquísima fuente de información sobre el estado de las ciencias en el siglo XVI, sino que cuenta con una dimensión traductológica de gran valor. Sin duda destaca la enorme aportación lexicográfica que lleva a cabo a través de un sinfín de americanismos, acompañados por unas definiciones y explicaciones que muestran el inagotable caudal de sabiduría y experiencia de su autor. También recurre Acosta a otros procedimientos traslativos a la hora de explicitar, desde una perspectiva europea aunque matizada por un tamiz indigenista, a un público europeo los rasgos idiosincrásicos del Nuevo Mundo. A partir de la contextualización de la obra y del establecimiento de los rasgos estructurales característicos, el estudio se dedica al análisis de los aspectos traslativos del texto.The Natural and Moral History of the Indies, published in Seville in 1590, is the most famous work by Father José de Acosta (1540-1600) and one of the most important pieces of missionary literature. It has enjoyed widespread reception thanks to numerous reissues and translations, a true reflection of its quality. It offers not only an ample insight into the state of art of the sciences in the 16th century, but it also includes very interesting translation aspects. What stands out is a large lexicographic contribution of Americanisms followed by definitions and explanations that show the endless wealth of knowledge and experience of the author. When it comes to explaining the idiosyncratic features of the New World (from a European perspective, though with an indigenist filter), Acosta uses other translation processes as well. After contextualizing the work and establishing its characteristic structural features, the article analyses the translation aspects of the text.A História natural e moral das Índias, publicada em Sevilha em 1590, é a obra mais célebre do Padre José de Acosta (1540-1600) e um dos textos mais importantes da literatura missionária. A qualidade excecional desta obra escrita explica a grande difusão alcançada decorrente das numerosas reedições e traduções. Não supõe apenas uma riquíssima fonte de informação sobre o estado das ciências no século XVI, pois conta também com uma dimensão tradutológica de grande valor. Sem dúvida alguma, destaca a enorme contribuição lexicográfica levada a cabo através de um sem-fim de americanismos, acompanhados por umas definições e explicações que mostram o inesgotável caudal de sabedoria e experiência do seu autor. Acosta, recorre também a outros procedimentos translativos na altura de explicitar, a partir de uma perspetiva europeia, embora matizada por um crivo indigenista, para um público europeu, as características idiossincrásicas do Novo Mundo. A partir da contextualização da obra e do estabelecimento dos aspetos estruturais característicos, o estudo é dedicado à análise dos aspetos translativos do texto

Exclusive tensor meson photoproduction

We study tensor meson photoproduction outside of the resonance region, at beam energies of few GeVs. We build a model based on Regge theory that includes the leading vector and axial exchanges. We consider two determinations of the unknown helicity couplings, and fit to the recent a2 photoproduction data from CLAS. Both choices give a similar description of the a2 cross section, but result in different predictions for the parity asymmetries and the f2 photoproduction cross section. We conclude that new measurements of f2 photoproduction in the forward region are needed to pin down the correct production mechanism. We also extend our predictions to the 8.5 GeV beam energy, where current experiments are running.Comment: 13 pages, 7 figures, 3 tables. Version accepted for publication on Phys.Rev.

Validation of two complementary oral-health related quality of life indicators (OIDP and OSS 0-10 ) in two qualitatively distinct samples of the Spanish population

<p>Abstract</p> <p>Background</p> <p>Oral health-related quality of life can be assessed positively, by measuring satisfaction with mouth, or negatively, by measuring oral impact on the performance of daily activities. The study objective was to validate two complementary indicators, i.e., the OIDP (Oral Impacts on Daily Performances) and Oral Satisfaction 0–10 Scale (OSS), in two qualitatively different socio-demographic samples of the Spanish adult population, and to analyse the factors affecting both perspectives of well-being.</p> <p>Methods</p> <p>A cross-sectional study was performed, recruiting a Validation Sample from randomly selected Health Centres in Granada (Spain), representing the general population (n = 253), and a Working Sample (n = 561) randomly selected from active Regional Government staff, i.e., representing the more privileged end of the socio-demographic spectrum of this reference population. All participants were examined according to WHO methodology and completed an in-person interview on their oral impacts and oral satisfaction using the OIDP and OSS 0–10 respectively. The reliability and validity of the two indicators were assessed. An alternative method of describing the causes of oral impacts is presented.</p> <p>Results</p> <p>The reliability coefficient (Cronbach's alpha) of the OIDP was above the recommended 0.7 threshold in both Validation and Occupational samples (0.79 and 0.71 respectively). Test-retest analysis confirmed the external reliability of the OSS (Intraclass Correlation Coefficient, 0.89; p < 0.001) Some subjective factors (perceived need for dental treatment, complaints about mouth and intermediate impacts) were strongly associated with both indicators, supporting their construct and criterion validity. The main cause of oral impact was dental pain. Several socio-demographic, behavioural and clinical variables were identified as modulating factors.</p> <p>Conclusion</p> <p>OIDP and OSS are valid and reliable subjective measures of oral impacts and oral satisfaction, respectively, in an adult Spanish population. Exploring simultaneously these issues may provide useful insights into how satisfaction and impact on well-being are constructed.</p

Reactivity of OH and CH3OH between 22 and 64 K: Modelling the gas phase production of CH3O in Barnard 1b

In the last years, ultra-low temperature chemical kinetic experiments have demonstrated that some gas-phase reactions are much faster than previously thought. One example is the reaction between OH and CH3OH, which has been recently found to be accelerated at low temperatures yielding CH3O as main product. This finding opened the question of whether the CH3O observed in the dense core Barnard 1b could be formed by the gas-phase reaction of CH3OH and OH. Several chemical models including this reaction and grain-surface processes have been developed to explain the observed abundance of CH$_3$O with little success. Here we report for the first time rate coefficients for the gas-phase reaction of OH and CH3OH down to a temperature of 22 K, very close to those in cold interstellar clouds. Two independent experimental set-ups based on the supersonic gas expansion technique coupled to the pulsed laser photolysis-laser induced fluorescence technique were used to determine rate coefficients in the temperature range 22-64 K. The temperature dependence obtained in this work can be expressed as k(22-64 K) = (3.6+/-0.1)e-12 (T/ 300)^(-1.0+/-0.2) cm3 molecule-1 s-1. Implementing this expression in a chemical model of a cold dense cloud results in CH3O/CH3OH abundance ratios similar or slightly lower than the value of 3e-3 observed in Barnard 1b. This finding confirms that the gas-phase reaction between OH and CH3OH is an important contributor to the formation of interstellar CH3O. The role of grain-surface processes in the formation of CH3O, although it cannot be fully neglected, remains controversial.Comment: Accepted for publication in The Astrophysical Journa