Bounds on gamma from CP violation measurements in B -> pi+ pi- and B -> psi K_S

We study the determination of gamma from CP-violating observables in B -> pi+ pi- and B -> psi K_S. This determination requires theoretical input to one combination of hadronic parameters. We show that a mild assumption about this quantity may allow bounds to be placed on gamma, but we stress the pernicious effects that an eightfold discrete ambiguity has on such an analysis. The bounds are discussed as a function of the direct (C) and interference (S) CP-violating observables obtained from time-dependent B -> pi+ pi- decays, and their behavior in the presence of new physics effects in B-Bbar mixing is studied. (V2: Misprints corrected. Slightly improved discussion.)Comment: 11 pages, RevTex 4, 5 eps figures include

Mass-degenerate Higgs bosons at 125 GeV in the Two-Higgs-Doublet Model

The analysis of the Higgs boson data by the ATLAS and CMS Collaborations appears to exhibit an excess of h --> gamma\gamma events above the Standard Model (SM) expectations; whereas no significant excess is observed in h --> ZZ* --> {four lepton} events, albeit with large statistical uncertainty due to the small data sample. These results (assuming they persist with further data) could be explained by a pair of nearly mass-degenerate scalars, one of which is a SM-like Higgs boson and the other is a scalar with suppressed couplings to W+W- and ZZ. In the two Higgs doublet model, the observed \gamma\gamma and ZZ* --> {four lepton} data can be reproduced by an approximately degenerate CP-even (h) and CP-odd (A) Higgs boson for values of \sin(\beta-\alpha) near unity and 0.7 < \tan\beta < 1. An enhanced \gamma\gamma signal can also arise in cases where m_h ~ m_H, m_H ~ m_A, or m_h ~ m_H ~ m_A. Since the ZZ* --> {four lepton} signal derives primarily from a SM-like Higgs boson whereas the \gamma\gamma signal receives contributions from two (or more) nearly mass-degenerate states, one would expect a slightly different invariant mass peak in the ZZ* --> {four lepton} and \gamma\gamma channels. The phenomenological consequences of such models can be tested with additional Higgs data that will be collected at the LHC in the near future.Comment: 18 pages, 19 pdf figures, v2: references added, v3&v4: added refs and explanation

The footloose entrepreneur model with a finite number of equidistant regions

We study the Footloose Entrepreneur model with a finite number of equidistant regions, focusing on the analysis of stability of agglomeration, total dispersion, and boundary dispersion. As the number of regions increases, there is more tendency for agglomeration and less tendency for dispersion. As it tends to infinity, agglomeration always becomes stable while dispersion always becomes unstable. These results are robust to any composition of the global workforce and its dependence on the number of regions. Numerical evidence suggests that boundary dispersion is never stable. We introduce exogenous regional heterogeneity and obtain a general condition for stability of agglomeration.info:eu-repo/semantics/acceptedVersio

Agglomeration patterns in a multi-regional economy without income effects

We study the long-run spatial distribution of industry using a multi-region core–periphery model with quasi-linear log utility Pflüger (Reg Sci Urban Econ 34:565–573, 2004). We show that a distribution in which industry is evenly dispersed among some of the regions, while the other regions have no industry, cannot be stable. A spatial distribution where industry is evenly distributed among all regions except one can be stable, but only if that region is significantly more industrialized than the other regions. When trade costs decrease, the type of transition from dispersion to agglomeration depends on the fraction of workers that are mobile. If this fraction is low, the transition from dispersion to agglomeration is catastrophic once dispersion becomes unstable. If it is high, there is a discontinuous jump to partial agglomeration in one region and then a smooth transition until full agglomeration. Finally, we find that mobile workers benefit from more agglomerated spatial distributions, whereas immobile workers prefer more dispersed distributions. The economy as a whole shows a tendency towards overagglomeration for intermediate levels of trade costs.info:eu-repo/semantics/acceptedVersio

Economic geography meets hotelling: a home-sweet-home effect

We propose a 2-region core-periphery model where all agents are inter-regionally mobile and have Hotelling-type heterogeneous preferences for location. The utility penalty from residing in a location that is not the preferred one generates the only dispersive force of the model: the home-sweet-home effect. Different distributions of preferences for location induce different spatial distributions in the long-run depending on the short-run general equilibrium economic geography model that is considered. We study the effect of two of those: the linear and the logit home-sweet-home effects.info:eu-repo/semantics/publishedVersio

Degradation of lithium Iron phosphate-based cathode in lithium-ion batteries: a post-mortem analysis

Commercial Li-ion batteries were studied in view to investigate the degradation of the positive electrode in an end-of-life battery condition. Post-mortem analyses were performed by using SEM and DRX techniques; structural and morphological changes after prolonged cycling were evaluated comparatively to a fresh cathode sample. The cycling procedure based on a constant current (CC)/constant voltage (CV) charge and CC discharge was executed, being the condition of end-of-life battery achieved after submitting the Li-ion battery to nearly 2000 charge/discharge cycles. EDS analysis revealed zirconium element as the dopant of a LiFePO4-based cathode of the battery under study. According to X-ray diffraction results for the fresh (charged condition) cathode, the positive electrode includes in its constitution a mixture of crystalline compounds, LiFePO4 and FePO4. SEM images displayed and DRX patterns obtained for the cycled cathode showed modifications compared to the fresh cathode results, evidencing the degradation of the battery at the end-of-life: decrease in the density of microparticles associated to areas where the insertion/de-insertion occurs; decrease of the LiFePO4/FePO4 ratio; both results pointed out to the occurrence of battery loss capacity with the imposed charge/discharge cycles

Remote Experimentation supported by Learning Analytics and Recommender Systems

This paper proposes a process based on learning analytics and recommender systems targeted at making suggestions to students about their remote laboratories activities and providing insights to all stakeholders taking part in the learning process. To apply the process, a log with requests and responses of remote experiments from the VISIR project were analyzed. A request is the setup of the experiment including the assembled circuits and the configurations of the measuring equipment. In turn, a response is a message provided by the measurement server indicating measures or an error when it is not possible to execute the experiment. Along the two phases of analysis, the log was analyzed and summarized in order to provide insights about students' experiments. In addition, there is a recommendation service responsible for analyzing the requests thus returning, in case of error, precise information about the assembly of circuits or configurations. The evaluation of the process is consistent in what regards its ability to afford recommendations to the students as they carry out the experiments. Moreover, the summarized information intends to offer teachers means to better understand and develop strategies to scaffold students' learning.info:eu-repo/semantics/publishedVersio

Remote Experimentation supported by Learning Analytics and Recommender Systems

This paper proposes a process based on learning analytics and recommender systems targeted at making suggestions to students about their remote laboratories activities and providing insights to all stakeholders taking part in the learning process. To apply the process, a log with requests and responses of remote experiments from the VISIR project were analyzed. A request is the setup of the experiment including the assembled circuits and the configurations of the measuring equipment. In turn, a response is a message provided by the measurement server indicating measures or an error when it is not possible to execute the experiment. Along the two phases of analysis, the log was analyzed and summarized in order to provide insights about students' experiments. In addition, there is a recommendation service responsible for analyzing the requests thus returning, in case of error, precise information about the assembly of circuits or configurations. The evaluation of the process is consistent in what regards its ability to afford recommendations to the students as they carry out the experiments. Moreover, the summarized information intends to offer teachers means to better understand and develop strategies to scaffold students' learning.info:eu-repo/semantics/publishedVersio

Detecting New Physics from CP-violating phase measurements in B decays

The standard CKM model can be tested and New Physics detected using only CP-violating phase measurements in B decays. This requires the measurement of a phase factor which is small in the Standard Model, in addition to the usual large phases $\beta$ and $\gamma$. We also point out that identifying violations of the unitarity of the CKM matrix is rather difficult, and cannot be done with phase measurements alone.Comment: 6 pages, Latex, no figure