Finite width induced modification to the electromagnetic form factors of spin-1 particles

The inclusion of the unstable features of a spin-1 particle, without breaking the electromagnetic gauge invariance, can be properly accomplished by including higher order contributions as done in the so-called fermion loop scheme (for the W gauge boson), and the boson loop scheme (for vector mesons). This induces a non trivial modification to the electromagnetic vertex of the particle, which must be considered in addition to any other contribution computed as stable particles. Considering the modified electromagnetic vertex, we obtain general expressions for the corresponding corrections to the multipoles as a function of the mass of the particles in the loop. For the W gauge boson no substantial deviations from the stable case is observed. For the rho and K* mesons the mass of the particles in the loop makes a significant effect, and can be comparable with corrections of different nature .Comment: 11 pages, 1 figure. Extended discussion, main equations rewritten to exhibit limiting behavior. Results for K* meson added. Accepted for publication in PR

Classical resolution of black hole singularities via wormholes

In certain extensions of General Relativity, wormholes generated by spherically symmetric electric fields can resolve black hole singularities without necessarily removing curvature divergences. This is shown by studying geodesic completeness, the behavior of time-like congruences going through the divergent region, and by means of scattering of waves off the wormhole. This provides an example of the logical independence between curvature divergences and space-time singularities, concepts very often identified with each other in the literature.ns of curvature divergences in the context of space-time singularities.Comment: 6 pages, 4 figures; several improvements in main body and abstract; final version to appear in Eur. Phys. J.

The INTEGRAL-OMC Scientific Archive

The Optical Monitoring Camera (OMC) on-board the INTEGRAL satellite has, as one of its scientific goals, the observation of a large number of variable sources previously selected. After almost 6 years of operations, OMC has monitored more than 100 000 sources of scientific interest. In this contribution we present the OMC Scientific Archive (http://sdc.laeff.inta.es/omc/) which has been developed to provide the astronomical community with a quick access to the light curves generated by this instrument.We describe the main characteristics of this archive, as well as important aspects for the users: object types, temporal sampling of light curves and photometric accuracy.Comment: 4 pages, 5 figures. "Highlights of Spanish Astrophysics V" Proceedings of the VIII Scientific Meeting of the Spanish Astronomical Society (SEA) held in Santander, July 7-11, 200