Three-antenna two-dimensional imaging correlation radiometer: concept and preliminary results

Peer ReviewedPostprint (published version

Matter-antimatter asymmetry without departure from thermal equilibrium

We explore the possibility of baryogenesis without departure from thermal equilibrium. A possible scenario is found, though it contains strong constraints on the size of the $CPT$ violation ($CPTV$) effects and on the role of the $B$ (baryon number) nonconserving interactions which are needed for it.Comment: Revtex, 4page

Characterization of periodic cavitation in an optical tweezer

Microscopic vapor explosions or cavitation bubbles can be generated periodically in an optical tweezer with a microparticle that partially absorbs at the trapping laser wavelength. In this work we measure the size distribution and the production rate of cavitation bubbles for microparticles with a diameter of 3 $\mu$m using high speed video recording and a fast photodiode. We find that there is a lower bound for the maximum bubble radius $R_{max}\sim 2~\mu$m which can be explained in terms of the microparticle size. More than $94 \%$ of the measured $R_{max}$ are in the range between 2 and 6 $\mu$m, while the same percentage of the measured individual frequencies $f_i$ or production rates are between 10 and 200 Hz. The photodiode signal yields an upper bound for the lifetime of the bubbles, which is at most twice the value predicted by the Rayleigh equation. We also report empirical relations between $R_{max}$, $f_i$ and the bubble lifetimes.Comment: 5 pages, 3 figure

Time evolution of the behaviour of Brazilian legislative Representatives using a complex network approach

The follow up of Representative behavior after elections is imperative for a democratic Representative system, at the very least to punish betrayal with no re-election. Our goal was to show how to follow Representatives' and how to show behavior in real situations and observe trends in political crises including the onset of game changing political instabilities. We used correlation and correlation distance matrices of Brazilian Representative votes during four presidential terms. Re-ordering these matrices with Minimal Spanning Trees displays the dynamical formation of clusters for the sixteen year period, which includes one Presidential impeachment. The reordered matrices, colored by correlation strength and by the parties clearly show the origin of observed clusters and their evolution over time. When large clusters provide government support cluster breaks, political instability arises, which could lead to an impeachment, a trend we observed three years before the Brazilian President was impeached. We believe this method could be applied to foresee other political storms.Comment: 11 pages, 4 Figure

Cosmic Neutrinos as a Window to Departures from Special Relativity

We review the peculiarities that make neutrinos very special cosmic messengers in high-energy astrophysics, and, in particular, to provide possible indications of deviations from special relativity, as it is suggested theoretically by quantum gravity models. In this respect, we examine the effects that one could expect in the production, propagation, and detection of neutrinos, not only in the well-studied scenario of Lorentz Invariance Violation, but also in models which maintain, but deform, the relativity principle, such as those considered in the framework of Doubly Special Relativity. We discuss the challenges and the promising future prospects offered by this phenomenological window to physics beyond special relativity

Dynamic Kinetic Resolution of Hetero biaryl Ketones by Zinc- Catalyzed Asymmetr ic Hydrosil ylation

Adiastereo- and highly enantioselective dynamic kinetic resolution (DKR) of configurationally labile hetero- biaryl ketones is described. The DKR proceeds by zinc- catalyze dhydrosilylation of the carbonyl group ,thus leading to secondary alcohols bearing axial and central chirality .The strategy relies on the labilization of the stereogenic axis that takes place thanks to aLewis acid–base interaction between anitrogen atom in the heterocycle and the ketone carbonyl group .The synthetic utility of the methodology is demonstrated through stereospecific transformations into either N,N-ligands or appealing axially chiral, bifunctional thiourea organocata- lysts.Ministerio de Ciencia e Innovación (Grants CTQ2016-76908-C2-1-P, CTQ2016-76908-C2-2-P, contract RYC-2013-12585)European FEDER FundsJunta de Andalucía (Grant 2012/FQM 10787)European Union - Marie Skłodowska-Curie (COFUND—Grant Agreement n 8 8 291780

Shake-up effects and intermolecular tunneling in C60 ions

4 págs.;1 fig.; 3 tabs. ; Rapid CommunicationsThe multiplet structure induced by the Coulomb interactions in C60 n- (n=1-12) is analyzed. The lowest partially occupied molecular orbital gives rise to a set of levels that fill a relatively wide band (2-3 eV). A large (∼1 eV) intramolecular effective repulsion is found. The anions are also shown to be highly polarizable. The optical-absorption and photoemission spectra are calculated. The probability of exciting the molecule upon the addition or removal of one electron is shown to be significant, and this effect may give rise to the insulating behavior of K4C60. The role of intermolecular interactions in suppressing the net repulsion within the C60 molecules is discussed. © 1994 The American Physical Society.Peer Reviewe

Contaminación de suelos y aguas subterraneas por vertidos industriales

In the industrialised countries, soil and groundwater contamination caused by uncontrolled spills of industrial wastes is one of the most critical environmental problem, because its removal is expensive and difficult to carry out, and the effects persist during many years. In Spain this problem is especially notorious due to an inadequate management policy derived from the absence of coordination between the different involved sectors. The treatment installations are inot enough, so it has produced spillings in streams and soils or its storage in uncontrolled landfillings.The experiences and guidelines of the Environmental Protection Agency from United States have served to the industrialised countries to evaluate this kind of contamination. This methodology is based on its identification and delimitation in soil and groundwater. After the design of a monitoring and control program it can be established the correcting measures. For this reason it is important to know the transfer processes of pollutants between the saturated and not saturated medium, for this reason it is essential the use of geochemical and geophysical methods and their combination with hydrogeological methods.In Spain, this kind of studies is only carried out recently. A case history is the contamination of the alluvial aquifer of the Besos river (Barcelona) by Cr-VI and other heavy metals and organic microcontaminants