The measurement of sin(2beta)

Since the first observation in 1964, CP violation remains one of the most elusive aspects of the standard model. The CDF collaboration has reported the first evidence of CP violation in the B system using the world's largest sample of $B \to J/\psi K^0_S$ decays. The direct measurement of sin$(2\beta)$=0.79$^{+0.41}_{-0.44}$ (combined statistical and systematic error) agrees with the standard model predictions. New data collected from the B-factories and from the upgraded experiments at the Tevatron should allow a more precise measurement of $\sin 2\beta$ in the near future.Comment: Presented at Heavy Flavours 8, Southampton, UK, 1999. Ten pages, 4 figure

The Importance of Silicon Detectors for the Higgs Boson Discovery and the Study of its Properties

Recent studies are presented demonstrating the important role played by silicon detectors in the the discovery of the Higgs boson. CMS is planning to replace its in an extended technical stop of the LHC in the winter of 2016 . We present results showing that this replacement will significant increase the sample of Higgs bosons that will be reconstructed enabling precision studies of this particle.Comment: on behalf of the CMS Collaboratio

Piracicaba river basin : mechanical and chemical erosion

It was carried out the characterization of the mechanical and chemical erosive processes in the Piracicaba River basin, for the period 1992-1996, in terms of the fluvial transport of dissolved and particulate materials. The mechanical erosion was calculated from the suspended sediment transport in the basin, considering the surface runoff discharge and the respective concentration calculated taking in account the statistical hydrogram separation method employed. The specific physical degradation calculated for the Piracicaba River basin was 90 t/km2.a, which correspond the velocity of the soil thickness reduction of about 64 m/Ma. The dissolved load of Piracicaba River was corrected due to the influence of the atmospheric inputs, mainly for SO4 2-, Ca2+ and Mg2+ (79.6; 63.8 and 41.8%, respectively). After the input corrections, it was estimated the total atmospheric/soil CO2 consumed during the silicate weathering (229 x 103 moles/km2.a) and the total chemical erosion (16.6 t/km2.a) expressed in terms of the total dissolved solids transported in the basin. The velocity of the silicate rock profile reduction (2.8 m/Ma) was calculated by the fluvial transport of dissolved silica knowing the mean silica concentrations in the parent rock and in the soil profile

A study of the evolution of the accretion disk of V2051 Oph through two outburst cycles

We follow the changes in the structure of the accretion disk of the dwarf nova V2051 Oph along two separate outbursts in order to investigate the causes of its recurrent outbursts. We apply eclipse mapping techniques to a set of light curves covering a normal (July 2000) and a low-amplitude (August 2002) outburst to derive maps of the disk surface brightness distribution at different phases along the outburst cycles. The sequence of eclipse maps of the 2000 July outburst reveal that the disk shrinks at outburst onset while an uneclipsed component of 13 per cent of the total light develops. The derived radial intensity distributions suggest the presence of an outward-moving heating wave during rise and of an inward-moving cooling wave during decline. The inferred speed of the outward-moving heating wave is ~ 1.6 km/s, while the speed of the cooling wave is a fraction of that. A comparison of the measured cooling wave velocity on consecutive nights indicates that the cooling wave accelerates as it travels towards disk center, in contradiction with the prediction of the disk instability model. From the inferred speed of the heating wave we derive a viscosity parameter alpha_{hot} ~ 0.13, comparable to the measured viscosity parameter in quiescence. The 2002 August outburst had lower amplitude (\Delta B ~ 0.8 mag) and the disk at outburst maximum was smaller than on 2000 July. For an assumed distance of 92 pc, we find that along both outbursts the disk brightness temperatures remain below the minimum expected according to the disk instability model. The results suggest that the outbursts of V2051 Oph are caused by bursts of increased mass transfer from the mass-donor star.Comment: 22 pages, 11 postscript figures, written with aastex macro package. To appear in the August 2007 issue of The Astronomical Journa