Single top polarisation as a window to new physics

We discuss the effect of heavy new physics, parameterised in terms of four-fermion operators, in the polarisation of single top (anti-)quarks in the $t$-channel process at the LHC. It is found that for operators involving a right-handed top quark field the relative effect on the longitudinal polarisation is twice larger than the relative effect on the total cross section. This enhanced dependence on possible four-fermion contributions makes the polarisation measurements specially interesting, in particular at high momenta.Comment: LaTeX 10 pages. v2: comments and references added, journal versio

New Results in the CBF theory for medium-heavy nuclei

Momentum distributions, spectroscopic factors and quasi-hole wave functions of medium-heavy doubly closed shell nuclei have been calculated in the framework of the Correlated Basis Function theory, by using the Fermi hypernetted chain resummation techniques. The calculations have been done by using microscopic two-body nucleon-nucleon potentials of Argonne type, together with three-body interactions. Operator dependent correlations, up to the tensor channels, have been used.Comment: 6 pages, 3 figures, proceeding of the "XI Convegno su problemi di Fisica Nucleare Teorica" 11-14 Ottobre 2006, Cortona, Ital

Optimal quantum state reconstruction for cold trapped ions

We study the physical implementation of an optimal tomographic reconstruction scheme for the case of determining the state of a multi-qubit system, where trapped ions are used for defining qubits. The protocol is based on the use of mutually unbiased measurements and on the physical information described in H. H\"{a}ffner \emph{et. al} [Nature \textbf{438}, 643-646 (2005)]. We introduce the concept of physical complexity for different types of unbiased measurements and analyze their generation in terms of one and two qubit gates for trapped ions.Comment: Accepted for publication in Phys. Rev. A as Rap. Com

Post-Privatization Renegotiation and Disputes in Chile

Over the last decade, Chile has undertaken remarkable reforms and transferred publicly owned utilities to the private sector either by selling the assets or through concession agreements. Because of the reforms the country has been able to attract private participation in the provision of public services like energy, transportation, telecommunications, potable water and sewage. In this paper, the authors analyze a series of post-privatization disputes and renegotiations that have taken place in Chile since the late 1980s in the electricity sector. This sector was chosen because the privatization process was, to a large extent, completed a decade ago, providing enough time to properly evaluate negotiations and disputes. The paper also assesses how lessons learned in the reform of electricity were internalized in the design of the regulatory framework for other concessions.Public Utilities, Electricity, Private Sector, IFM-116, electricity sector, dispute renegotiation, Chile, infrastructure, privatization

Top effective operators at the ILC

We investigate the effect of top trilinear operators in t tbar production at the ILC. We find that the sensitivity to these operators largely surpasses the one achievable by the LHC either in neutral or charged current processes, allowing to probe new physics scales up to 4.5 TeV for a centre of mass energy of 500 GeV. We show how the use of beam polarisation and an eventual energy upgrade to 1 TeV allow to disentangle all effective operator contributions to the Ztt and gamma tt vertices.Comment: LaTeX 13 pages. Typos corrected. Final version in JHE

Top effective operators at the ILC

We investigate the effect of top trilinear operators in t tbar production at the ILC. We find that the sensitivity to these operators largely surpasses the one achievable by the LHC either in neutral or charged current processes, allowing to probe new physics scales up to 4.5 TeV for a centre of mass energy of 500 GeV. We show how the use of beam polarisation and an eventual energy upgrade to 1 TeV allow to disentangle all effective operator contributions to the Ztt and gamma tt vertices.Comment: LaTeX 13 pages. Typos corrected. Final version in JHE

Ground state of medium-heavy doubly-closed shell nuclei in correlated basis function theory

The correlated basis function theory is applied to the study of medium-heavy doubly closed shell nuclei with different wave functions for protons and neutrons and in the jj coupling scheme. State dependent correlations including tensor correlations are used. Realistic two-body interactions of Argonne and Urbana type, together with three-body interactions have been used to calculate ground state energies and density distributions of the 12C, 16O, 40Ca, 48Ca and 208Pb nuclei.Comment: Latex 10 pages, 3 Tables, 10 Figure