B+→K−π+π+B^+\to K^-\pi^+\pi^+: three-body final state interactions and KπK\pi isospin states

Final state interactions are considered to formulate the $B$ meson decay amplitude for the $K\pi\pi$ channel. The Faddeev decomposition of the Bethe-Salpeter equation is used in order to build a relativistic three-body model within the light-front framework. The S-wave scattering amplitude for the $K\pi$ system is considered in the $1/2$ and $3/2$ isospin channels with the set of inhomogeneous integral equations solved perturbatively. In comparison with previous results for the $D$ meson decay in the same channel, one has to consider the different partonic processes, which build the source amplitudes, and the larger absorption to other decay channels appears, that are important features to be addressed. As in the $D$ decay case, the convergence of the rescattering perturbative series is also achieved with two-loop contributions.Comment: 10 pages, 4 figure

Seismic behaviour of vernacular architecture

Vernacular buildings are in several seismic prone regions a relevant part of the building stock. They represent an important part of the of the cultural legacy, and of the technological and heritage context of the society. The present paper presents a revision of the effect of recent earthquake disasters in old buildings, and discusses the influence of the main structural elements in the vulnerability of these buildings, as well as the more common failure mechanisms. Finally, it is presented a review on the elements that more contribute to the seismic behaviour and performance of vernacular buildings.Project ‘SEISMIC-V –Vernacular Seismic Culture in Portugal’ (PTDC/ATP-AQI/3934/2012), from the Portuguese Science and Technology Foundation (FCT

Structural conservation and vernacular construction

Modern societies understand built cultural heritage, including vernacular construction, as a landmark of culture and diversity, which needs to be protected and brought to the next generations in suitable condition. Still, a large part of this heritage is affected by structural problems that menace the safety of buildings and people. In the case of vernacular construction, deterioration due to abandonment is often present, making the phenomena of urbanization one of the most important menaces to this built heritage. The developments in the areas of inspection, non-destructive testing, monitoring and structural analysis of historical constructions, together with recent guidelines for reuse and conservation, allow for safer, economical and adequate remedial measures, as discussed in this paperProject ‘SEISMIC - V – Vernacular Seismic Culture in Portugal’ (PTDC/ATP - AQI/ 3934/2012) , from the Portuguese Science and Technology Foundation (FCT

Avaliação de segurança de estruturas de madeira através de análise probabilística

O presente trabalho apresenta diferentes modelos geométricos e mecânicos na definição de parâmetros probabilísticos de avaliação de segurança para estruturas existentes em madeira, influenciadas por diferentes acções e atendendo a modelos de degradação. O caso de estudo é referente às asnas do Laboratório Chimico, em Coimbra, tendo a avaliação de segurança sido analisada através da técnica de simulação de Monte Carlo

Dark particle mass effects on neutron star properties from a short-range correlated hadronic model

In this work we study a relativistic mean-field (RMF) hadronic model, with nucleonic short-range correlations (SRC) included, coupled to dark matter (DM) through the Higgs boson. We study different parametrizations of this model by running the dark particle Fermi momentum, and its mass in the range of $50$ GeV $\leqslant M_\chi\leqslant 500$ GeV, compatible with experimental spin-independent scattering cross-sections. By using this RMF-SRC-DM model, we calculate some neutron star quantities, namely, mass-radius profiles, dimensionless tidal deformabilities, and crustal properties. Our findings show that is possible to construct RMF-SRC-DM parametrizations in agreement with constraints provided by LIGO and Virgo collaboration (LVC) on the GW170817 event, and recent observational data from the NICER mission. Furthermore, we show that the increase of $M_\chi$ favors the model to attain data from LVC regarding the tidal deformabilities. Higher values of $M_\chi$ also induce a reduction of the neutron star crust (mass and thickness), and cause a decrease of the crustal fraction of the moment of inertia ($I_{\rm{\tiny crust}}/I$). Nevertheless, we show that some RMF-SRC-DM parametrizations still exhibit $I_{\rm{\tiny crust}}/I>7\%$, a condition that explains the glitch activity in rotation-powered pulsars such as the Vela one. Therefore, dark matter content can also be used for describing such a phenomenon.Comment: 10 pages, 8 figures. Published in Monthly Notices of the Royal Astronomical Societ