1,163 research outputs found
Strange resonance poles from scattering below 1.8 GeV
In this work we present a determination of the mass, width and coupling of
the resonances that appear in kaon-pion scattering below 1.8 GeV. These are:
the much debated scalar -meson, nowdays known as , the
scalar , the and vectors, the spin-two
as well as the spin-three . The parameters will be
determined from the pole associated to each resonance by means of an analytic
continuation of the scattering amplitudes obtained in a recent and
precise data analysis constrained with dispersion relations, which were not
well satisfied in previous analyses. This analytic continuation will be
performed by means of Pad\'e approximants, thus avoiding a particular model for
the pole parameterization. We also pay particular attention to the evaluation
of uncertainties.Comment: 13 pages, 12 figures. Accepted version to appear in Eur. Phys. J. C.
Clarifications and references added, minor typos correcte
Un hombre del renacimiento
Areilza describe una visita a los Baroja, y define a Caro Baroja como un hombre del Renacimiento que se dedicó a la historia, arqueología, a escribir, dibujar y pintarAreilza describes a visit to Baroja, and defines Caro Baroja as a man of the Renaissance that was devoted to the history, archaeology, writing, drawing and paintin
Recommended from our members
Childhood family socioeconomic status is linked to adult brain electrophysiology.
A large body of research has linked childhood family socioeconomic status (SES) to neurodevelopment in childhood and adolescence. However, it remains unclear to what extent childhood family SES relates to brain functioning in adulthood. To address this gap, the present study investigated the associations between retrospective accounts of objective and subjective childhood family SES and two well-established electrophysiological indices of brain functioning in adulthood-the MMN and P3b event-related potentials (ERP) components, as neural correlates of automatic change detection and cognitive control respectively. Higher objective childhood family SES, as proxied by parent educational attainment in childhood, was associated with larger (more positive) P3b amplitudes in adulthood. In contrast, there was no association between childhood parent educational attainment and the magnitude of MMN. Adult reports of subjective family SES during childhood were not related to the magnitude of MMN or P3b. These findings suggest that the links between childhood parent educational attainment and brain functioning may extend into adulthood, especially for brain functions supporting cognitive control. These results also imply that, when using retrospective accounts of childhood family SES, objective and subjective reports likely proxy different childhood experiences that have distinct links with specific neurodevelopmental outcomes, and that some of these links may not persist into adulthood. Our findings lay the groundwork for future investigations on how and why childhood family SES relates to brain functioning in adulthood
Modelación de la degradación del 2-cloro-metil-propeno por la acción del radical cloro
Anais do IV Encontro de Iniciação Científica da Unila - “UNILA 5 anos: Integração em Ciência, Tecnologia e Cultura na Tríplice Fronteira” - 05 e 06 de novembro de 2015 – Sessão Química, Física e MatemáticaNo presente trabalho foi pesquisada a degradação do composto orgânico volátil 2-
cloro-metil-propeno produzida pela reação com átomos de cloro. Foram determinadas duas
estruturas de mínimos que garantem a possibilidade da reação do átomo de cloro com os átomos
de carbono da ligação dupla. No trabalho são reportadas as geometrias e frequências dos modos
normais de vibração dos estados estacionários correspondentes. Foi pesquisada a possível
existência de estados de transição vinculados aos mínimos determinados. Para determinar esses
estados estacionários foi mapeado o espaço de configuração da molécula, junto com o átomo de
cloro, na região das redondezas dos mínimos determinados utilizando cálculos pontuais de
energia e otimizações das configurações geométricas prováveis. No foi encontrado nenhum
estado de transição associado aos mínimos determinados. O resultado reportado parece indicar
que o átomo de cloro entra no poço de potencial do mínimo sem passar por estado de transição.
Esse tipo de comportamento tem sido observado em outras reações.bolsa pibic UNIL
The f0(1370) controversy from dispersive meson-meson scattering data analyses
We establish the existence of the long-debated resonance in the
dispersive analyses of meson-meson scattering data. For this, we present a
novel approach using forward dispersion relations, valid for generic inelastic
resonances. We find its pole at MeV in
scattering. We also provide the couplings as well as further checks
extrapolating partial-wave dispersion relations or with other continuation
methods. A pole at MeV also appears
in the data analysis with partial-wave dispersion
relations. Despite settling its existence, our model-independent dispersive and
analytic methods still show a lingering tension between pole parameters from
the and channels that should be attributed to data.Comment: 14 pages, 7 figure
- …