Photoproduction of ρ0\rho^0 mesons in ultraperipheral heavy ion collisions at energies available at the BNL Relativistic Heavy Ion Collider (RHIC) and CERN Large Hadron Collider (LHC)

We investigate the photoproduction of $\rho$ mesons in ultraperipheral heavy ion collisions at RHIC and LHC energies in the dipole approach and within two phenomenological models based on the the Color Glass Condensate (CGC) formalism. We estimate the integrated cross section and rapidity distribution for meson production and compare our predictions with the data from the STAR collaboration. In particular, we demonstrate that the total cross section at RHIC is strongly dependent on the energy behavior of the dipole-target cross section at low energies, which is not well determined in the dipole approach. In contrast, the predictions at midrapidities at RHIC and in the full rapidity at LHC are under theoretical control and can be used to test the QCD dynamics at high energies.Comment: 6 pages, 5 figures, 1 table. Improved version to be published in Physical Review

Vector Meson Production in Coherent Hadronic Interactions: An update on predictions for RHIC and LHC

In this letter we update our predictions for the photoproduction of vector mesons in coherent $pp$ and $AA$ collisions at RHIC and LHC energies using the color dipole approach and the Color Glass Condensate (CGC) formalism. In particular, we present our predictions for the first run of the LHC at half energy and for the rapidity dependence of the ratio between the $J/\Psi$ and $\rho$ cross sections at RHIC energies.Comment: 4 pages, 3 figure

Influence of Disorder Strength on Phase Field Models of Interfacial Growth

We study the influence of disorder strength on the interface roughening process in a phase-field model with locally conserved dynamics. We consider two cases where the mobility coefficient multiplying the locally conserved current is either constant throughout the system (the two-sided model) or becomes zero in the phase into which the interface advances (one-sided model). In the limit of weak disorder, both models are completely equivalent and can reproduce the physical process of a fluid diffusively invading a porous media, where super-rough scaling of the interface fluctuations occurs. On the other hand, increasing disorder causes the scaling properties to change to intrinsic anomalous scaling. In the limit of strong disorder this behavior prevails for the one-sided model, whereas for the two-sided case, nucleation of domains in front of the invading front are observed.Comment: Accepted for publication in PR

QCD traveling waves phenomenology revisited

In this paper we review and update the Amaral-Gay Ducati-Betemps-Soyez saturation model, by testing it against the recent H1-ZEUS combined data on deep inelastic scattering, including heavy quarks in the dipole amplitude. We obtain that this model, which is based on traveling wave solutions of the Balitsky-Kovchegov equation and built in the momentum space framework, yields very accurate descriptions of the reduced cross section, $\sigma_{r}(x,y,Q^{2})$, as well as DIS structure functions such as $F_{2}(x,Q^{2})$ and $F_{L}(x,Q^{2})$, all measured at HERA. Additionally, it provides good descriptions of heavy quark structure functions, $F_{2}^{cc}$ and $F_{2}^{bb}$ at small-$x$ and $Q^{2}\lesssim 60$ GeV$^{2}$. We also use the improved model to make predictions for structure functions to be measured in the near future at LHeC.Comment: 13 pages, 7 figure

Trace metals on the Algarve coast, I: Associations, origins and remobilisation of natural components

The deep red colours observed on the topmost portions of cliffs along the Algarve coast are due to the presence of goethite/haematite pigments dispersed within the predominantly sandy sediments. Chemical and mineralogical analyses of these iron-enriched Pliocene/Quaternary siliciclastic sediments and of samples of terra rosa taken from carstic cavities in neighbouring calcareous terrains indicate the genetic link between these materials on the Algarve coast. The authors suggest that the terra rosas which developed on Tertiary and Mesozoic limestones were transported and deposited on top of sandy sediments cropping in a coastal area of the Algarve, during the period of erosion in Late Pliocene/Early Quaternary times. The distribution of trace elements in these sediments supports the conclusion that the later process of remobilisation and redistribution of the ferruginous pigments led to the formation of hardpans, globules and crusts. The dissolution and reprecipitation of the iron oxides leads to the transformation of goethite into haematite.Los colores rojo oscuro encontrados en las camadas superiores de los acantilados a lo largo de la costa del Algarve se deben a la presencia de pigmentos de goetita/hematita dispersos en los sedimentos predominantemente arenosos. Los análisis químicos y mineralógicos de muestras de estos sedimentos siliciclásticos enriquecidos de hierro, pertenecientes al Plioceno/Cuaternario, así como de las muestras de terra rosa tomadas de las cavidades cársticas en los terrenos calcáreos circundantes, permiten establecer la conexión genética entre ellas en la franja costera del Algarve. Se postula que, durante el periodo de erosión, las terra rosa desarrolladas sobre las calizas de Terciario y Mesozoico fueron transportadas y depositadas encima de los sedimentos arenosos aflorantes en el área costera del Algarve. El análisis de la distribución de elementos trazos en estos sedimentos ha permitido concluir que el último proceso de remobilización y redistribución de los pigmentos ferruginosos condujo a la formación de hardpans, glóbulos y costras. La disolución y reprecipitación de los óxidos de hierro, condujo a la transformación de la goetita en hematita.Instituto Español de Oceanografí