Measuring Global Similarity between Texts

We propose a new similarity measure between texts which, contrary to the current state-of-the-art approaches, takes a global view of the texts to be compared. We have implemented a tool to compute our textual distance and conducted experiments on several corpuses of texts. The experiments show that our methods can reliably identify different global types of texts.Comment: Submitted to SLSP 201

A Rationale for Long-lived Quarks and Leptons at the LHC: Low Energy Flavour Theory

In the framework of gauged flavour symmetries, new fermions in parity symmetric representations of the standard model are generically needed for the compensation of mixed anomalies. The key point is that their masses are also protected by flavour symmetries and some of them are expected to lie way below the flavour symmetry breaking scale(s), which has to occur many orders of magnitude above the electroweak scale to be compatible with the available data from flavour changing neutral currents and CP violation experiments. We argue that, actually, some of these fermions would plausibly get masses within the LHC range. If they are taken to be heavy quarks and leptons, in (bi)-fundamental representations of the standard model symmetries, their mixings with the light ones are strongly constrained to be very small by electroweak precision data. The alternative chosen here is to exactly forbid such mixings by breaking of flavour symmetries into an exact discrete symmetry, the so-called proton-hexality, primarily suggested to avoid proton decay. As a consequence of the large value needed for the flavour breaking scale, those heavy particles are long-lived and rather appropriate for the current and future searches at the LHC for quasi-stable hadrons and leptons. In fact, the LHC experiments have already started to look for them.Comment: 10 pages, 1 figur

MIRACLE Progress in Monolingual Information Retrieval at Ad-Hoc CLEF 2007

This paper presents the 2007 MIRACLE’s team approach to the Ad-Hoc Information Retrieval track. The main work carried out for this campaign has been around monolingual experiments, in the standard and in the robust tracks. The most important contributions have been the general introduction of automatic named-entities extraction and the use of Wikipedia resources. For the2007 campaign, runs were submitted for the following languages and tracks: a) Monolingual: Bulgarian, Hungarian, and Czech. b) Robust monolingual: French, English and Portuguese

Chiral Extensions of the MSSM

We present a class of extensions of the MSSM characterized by a fully chiral field content (no mu-terms) and no baryon or lepton number violating term in the superpotential due to an extra U'(1) gauge symmetry. The minimal model consist of the usual matter sector with family dependent U'(1) charges, six Higgs weak doublets, and three singlets required to give masses to the Higgsinos and cancel anomalies. We discuss its main features such as the tree level mass spectrum and the constraints on flavor changing processes.Comment: 13 pages. V2: Superpotential and U'(1) charges changed. Analysis of the spectrum for the new model added. References update

Constraints on Phases of Supersymmetric Flavour Conserving Couplings

In the unconstrained MSSM, we reanalyze the constraints on the phases of supersymmetric flavour conserving couplings that follow from the electron and neutron electric dipole moments (EDM). We find that the constraints become weak if at least one exchanged superpartner mass is >O(1 TeV) or if we accept large cancellations among different contributions. However, such cancellations have no evident underlying symmetry principle. For light superpartners, models with small phases look like the easiest solution to the experimental EDM constraints. This conclusion becomes stronger the larger is the value of $\tan\beta$. We discuss also the dependence of $\epsilon_K$, $\Delta m_B$ and $b\to s\gamma$ decay on those phases.Comment: 38 pages, 22 figures, uses epsfig.sty, axodraw.sty (not included); error in sign of gluino contribution to EDM of u and d quarks and few figures corrected, important conclusions unchange

MIRACLE at Ad-Hoc CLEF 2005: Merging and Combining Without Using a Single Approach

This paper presents the 2005 Miracle’s team approach to the Ad-Hoc Information Retrieval tasks. The goal for the experiments this year was twofold: to continue testing the effect of combination approaches on information retrieval tasks, and improving our basic processing and indexing tools, adapting them to new languages with strange encoding schemes. The starting point was a set of basic components: stemming, transforming, filtering, proper nouns extraction, paragraph extraction, and pseudo-relevance feedback. Some of these basic components were used in different combinations and order of application for document indexing and for query processing. Second-order combinations were also tested, by averaging or selective combination of the documents retrieved by different approaches for a particular query. In the multilingual track, we concentrated our work on the merging process of the results of monolingual runs to get the overall multilingual result, relying on available translations. In both cross-lingual tracks, we have used available translation resources, and in some cases we have used a combination approach

Silicon Data Acquisition and Front-End Electronics

A highly integrated Front-End readout and Data Acquisition scheme for Silicon trackers is presented. In this context, a 16-channel readout chip for Silicon strips detector has been designed in 180nm CMOS technology, having in view a highly multiplexed and sparsified readout global strategy. First results are presented

Front-end Electronics for Silicon Trackers readout in Deep Sub-Micron CMOS Technology: The case of Silicon strips at the ILC

For the years to come, Silicon strips detectors will be read using the smallest available integrated technologies for room, transparency, and power considerations. CMOS, Bipolar- CMOS and Silicon-Germanium are presently offered in deepsubmicron (250 down to 90nm) at affordable cost through worldwide integrated circuits multiproject centers. As an example, a 180nm CMOS readout prototype chip has been designed and tested, and gave satisfactory results in terms of noise and power. Beam tests are under work, and prospectives in 130nm will be presented

On Composite Two Higgs Doublet Models

We investigate composite two Higgs doublet models realized as pseudo Goldstone modes, generated through the spontaneous breaking of a global symmetry due to strong dynamic at the TeV scale. A detailed comparative survey of two possible symmetry breaking patterns, SU(5) -> SU(4) x U(1) and SU(5) x SU(4), is made. We point out choices for the Standard Model fermion representations that can alleviate some phenomenological constraints, with emphasis towards a simultaneous solution of anomalous Zb\bar{b} coupling and Higgs mediated Flavor Changing Neutral Currents. We also write down the kinetic lagrangian for several models leading to Two Higgs Doublets and identify the anomalous contributions to the T parameter. Moreover, we describe a model based on the breaking $SO(9)/SO(8)$ in which there is no tree-level breaking of custodial symmetry, discussing also the possible embeddings for the fermion fields.Comment: 17 pages. Mistake corrected, added one section on a T- and flavor safe model based on SO(9)/SO(8). Matches published versio