Magnetic Moments of Heavy ΞQ\Xi_{Q} Baryons in Light Cone QCD Sum Rules

The magnetic moments of heavy $\Xi_{Q}$ baryons containing a single charm or bottom quark are calculated in the framework of light cone QCD sum rules method. A comparison of our results with the predictions of the quark models is presented.Comment: 26 Pages, 8 Figures and 1 Tabl

Electromagnetic form factors of the (rho) meson in light cone QCD sum rules

We investigate the electromagnetic form factors of the (rho) meson in light cone QCD sum rules. We find that the ratio of the magnetic and charge form factors is larger than two at all values of Q^2, (Q^2 >= 0.5 GeV^2). The values of the individual form factors at fixed values of Q^2 predicted by the light cone QCD sum rules are quite different compared to the results of other approaches. These results can be checked in future, when more precise data on (rho) meson form factors is available.Comment: 12 pages, 6 figures, LaTeX formatte

Vertical dipoles to detect self potential signals in a seismic area of southern Italy: Tito station

International audienceSince 2000 the Institute of Methodologies for the Environmental Analysis (National Council of Research, Tito, Italy) installed a geophysical monitoring network able to detect geoelectric, geochemic and seismometric parameters in seismic areas of southern Italy. During this period a very large data-base of geophysical time series has been organized and it is actually available to assess robust statistical methodologies to identify geophysical anomalous patterns linked with local seismicity. To better understand the influence of rain and cultural noise on geoelectrical signals (Self Potential), during May 2004 we drilled in Tito station a 20 m-depth hole to measure the SP vertical component. The array is characterized by five Pb-PbCl2 electrodes put at different depths. The common electrode is fixed at 20 m. In this work we present some electrical anomalies probably correlated with local seismic activity on vertical dipoles recorded in Tito station

Multifractal variability in geoelectrical signals and correlations with seismicity: a study case in southern Italy

International audienceMultifractal fluctuations in the time dynamics of geoelectrical data, recorded in a seismic area of southern Italy, have been revealed using the Multifractal Detrended Fluctuation Analysis (MF-DFA), which allows to detect multifractality in nonstationary signals. Our findings show that the geoelectrical time series, recorded in the seismic area of southern Apennine Chain (Italy), is multifractal. The time evolution of the multifractality suggests that the multifractal degree increases prior the occurrence of earthquakes. This study aims to propose another approach to investigate the complex dynamics of earthquake-related geoelectrical signals

Rare Radiative Bc→Ds1(2460)γB_{c}\rightarrow D_{s1}(2460)\gamma Transition in QCD

We investigate the radiative $B_{c} \to D_{s1} \gamma$ transition in the framework of QCD sum rules. In particular, we calculate the transition form factors responsible for this decay in both weak annihilation and electromagnetic penguin channels using the quark condensate, mixed and two-gluon condensate diagrams as well as propagation of the soft quark in the electromagnetic field as non-perturbative corrections. These form factors are then used to estimate the branching ratios of the channels under consideration. The total branching ratio of the $B_{c} \to D_{s1} \gamma$ transition is obtained to be in order of $10^{-5}$, and the dominant contribution comes from the weak annihilation channel.Comment: 24 Pages and 3 Figure

Weak decays of heavy hadron molecules involving the f0(980)

We study weak decays of the charm- and bottom-strange mesons Ds0*(2317), Ds1(2460), Bs0*(5725) and Bs1(5778) with f0(980) in the final state by assuming a hadronic molecule interpretation for their structures. Since in the proposed framework the initial and final states are occupied by hadronic molecules, the predictions for observables can provide a sensitive tool to further test the hadronic molecule structure in future experiments.Comment: 11 pages, 5 figures, accepted for publication in Phys. Rev.

Chiral Lagrangians with tensor sources

The implementation of tensor sources in Chiral Lagrangians allows the computation of Green functions and form factors involving tensor currents, that is, quark bilinears of the form \bar{q}_i\sigma^{\mu\nu}q_j. Whereas only four new terms show up at O(p^4), we find around a hundred of them at O(p^6). So it becomes essential to ensure that this set o operators is indeed minimal and non-redundant (i.e., it is a basis). We discuss two phenomenological applications in the context of vector meson resonances and the radiative pion decay.Comment: Talk given at the 4th International Worshop on Quantum ChromoDynamics, Theory and experiment, June 16-20, 2007. Martina Franca - Valle d'Itria - Ital

Strong Interactions at Low Energy

The lectures review some of the basic concepts relevant for an understanding of the low energy properties of the strong interactions: chiral symmetry, spontaneous symmetry breakdown, Goldstone bosons, quark condensate. The effective field theory used to analyze the low energy structure is briefly sketched. As an illustration, I discuss the implications of the recent data on the decay $K\to \pi\pi e\nu$ for the magnitude of the quark condensate.Comment: Lectures given at the school of physics "Understanding the structure of hadrons", Prague, July 2001, 20 p

Morphology and chromosomes of Tatera Lataste 1882 (Rodentia Muridae Gerbillinae) in West Africa

In a sample of the genus Tatera Lataste 1882 from West Africa (Benin and Burkina Faso), we analyzed the cranial and dental morphology and the karyotype (G, R, C and NOR banding). The cranial morphology confirms the attribution of this sample to Tatera kempi Wroughton 1906. An analysis of the dental morphology was also performed but it seems not to offer diagnostic traits. The karyotype described in the present work for T. kempi is comparable with that described for T. hopkinsoni Thomas 1911, supporting the synonymy of these two taxa. In contrast, the karyological results clearly discriminate kempi from both guineae and nigrita, the latter currently considered a synonym. In the karyotype of T. kempi, we found a polymorphism of a small chromosome, which occurs in the three situations: metacentric/metacentric, metacentric/acrocentric and acrocentric/ acrocentric. A similar polymorphism was described for hopkinsoni. The banding shows that the variation of the morphology of the X chromosome in Tatera is related to a pericentric inversion. KEY WORDS: Tatera, rodents, chromosomes, taxonomy, West Africa, evolution