Prospects for ϕ\phi meson production in pp collisions at the ALICE experiment

The ALICE experiment at the CERN Large Hadron Collider (LHC) will allow the study of resonance production in nucleus-nucleus and proton-proton collisions. This paper presents results based on physics performance studies to discuss prospects in ALICE for $\phi$(1020) meson production in pp interactions during the LHC startup.Comment: To appear in the proceedings of International Conference on Strangeness in Quark Matter (SQM 2007), Levoca, Slovakia, 24-29 Jun 2007. Submitted to J.Phys.

First LHC results on coherent J/psi photoproduction in ultra-peripheral Pb-Pb collisions at sqrt{s_NN} = 2.76 TeV

The first LHC measurement on ultra-peripheral heavy-ion collisions was carried out with the ALICE experiment. In this paper, ALICE results on exclusive J/psi studies in Pb-Pb collisions at sqrt(s_NN) = 2.76 TeV, in the rapidity region -3.6 < y < -2.6, are given. The coherent J/psi cross section was found to be dsigma/dy_coh_J/\psi = 1.00 +/- 0.18 (stat) +0.24 -0.26 (syst) mb. These studies favour theoretical models that include strong modifications to the nuclear gluon density, also known as nuclear gluon shadowing.Comment: Presented at DIFFRACTION 2012: International Workshop on Diffraction in High-Energy Physics. Puerto del Carmen, Canary Islands, 10-15 September 201

Diversity of economic landscapes and common land persistence in 19th century Spain: an interpretative proposal

The massive land privatization that took place over the 19th century deeply transformed the Spanish economic landscape. Nevertheless, the outcome of the process was quite different, both in pace and impact, depending on the geographic area we analyze. The explanation for this regional diversity in the persistence of common lands has been attributed to the institutional and environmental context, together with the level of market penetration that characterized the different rural societies. However, the important role that the commons themselves played in this process has been often overlooked. The aim of this paper is to complement those previous explanations by proposing a model that focuses on the collective land remaining, at any given moment, as a crucial explanatory variable and to provide an interpretative framework that would contribute to unveiling the complexity of a process that led to so many different outcomes.Common lands, privatisation, Spain, 19th century.

Invariant and polynomial identities for higher rank matrices

We exhibit explicit expressions, in terms of components, of discriminants, determinants, characteristic polynomials and polynomial identities for matrices of higher rank. We define permutation tensors and in term of them we construct discriminants and the determinant as the discriminant of order $d$, where $d$ is the dimension of the matrix. The characteristic polynomials and the Cayley--Hamilton theorem for higher rank matrices are obtained there from

Mass dependence of vector meson photoproduction off protons and nuclei within the energy-dependent hot-spot model

We study the photoproduction of vector mesons off proton and off nuclear targets. We work within the colour dipole model in an approach that includes subnucleon degrees of freedom, so-called hot spots, whose positions in the impact-parameter plane change event-by-event. The key feature of our model is that the number of hot spots depends on the energy of the photon--target interaction. Predictions are presented for exclusive and dissociative production of $\rho^{0}$, $\mathrm{J/}\psi$, and $\Upsilon(1S)$ off protons, as well as for coherent and incoherent photoproduction of $\rho^{0}$ off nuclear targets, where Xe, Au, and Pb nuclei are considered. We find that the mass dependence of dissociative production off protons as a function of the energy of the interaction provides a further handle to search for saturation effects at HERA, the LHC and future colliders. We also find that the coherent photonuclear production of $\rho^{0}$ is sensitive to fluctuations in the subnucleon degrees of freedom at RHIC and LHC energies.Comment: 19 pages, 4 figures. Typo in legend of figs. 1 and 2 correcte

Thermal and mechanical properties of a DNA model with solvation barrier

We study the thermal and mechanical behavior of DNA denaturation in the frame of the mesoscopic Peyrard- Bishop-Dauxois model with the inclusion of solvent interaction. By analyzing the melting transition of a homogeneous A-T sequence, we are able to set suitable values of the parameters of the model and study the formation and stability of bubbles in the system. Then, we focus on the case of the P5 promoter sequence and use the Principal Component Analysis of the trajectories to extract the main information on the dynamical behavior of the system. We find that this analysis method gives an excellent agreement with previous biological results.Comment: Physical Review E (in press

Information transmission around block trades on the Spanish stock market

Current fmancial research is placing increasing attention on the effects of large transactions, or Block Trades (BT), on the fmancial markets. In order to analyze whether BT transmit information, we assume that information can be better reflected by changes in asset true value, proxied by the midpoint of bid-ask best quotes, instead of transactions prices or returns. Moreover, following market microstructure literature, we also look at changes in relative spread and in their adverse selection component. The Madrid Stock Exchange offers us a particularly appropriate testing ground for examining these issues, since this topic has not been facilitated as in other markets till 1998. We analyze 195 BT, classified according with trading volume, the side of the market initiating the BT (buyer, seller or indeterminate initiated), its type (inside the spread, sweeping or not classified) and if they change or not the asset true value. The main result of the paper is that it seems that there is BT information transmission when we look at adverse selection spread component in the different subsample classification, but there is no significant permanent effect in returns. We also observe changes in liquidity around BTs but the effect is related with temporary spread component