Are the low-momentum gluon correlations semiclassically determined?

We argue that low-energy gluodynamics can be explained in terms of semi-classical Yang-Mills solutions by demonstrating that lattice gluon correlation functions fit to instanton liquid predictions for low energies and, after cooling, in the whole range.Comment: 4 pages, revtex

Non-relativistic bound states at finite temperature (II): the muonic hydrogen

We illustrate how to apply modern effective field theory techniques and dimensional regularization to factorise the various scales which appear in QED bound states at finite temperature. We focus here on the muonic hydrogen atom. Vacuum polarization effects make the physics of this atom at finite temperature very close to that of heavy quarkonium states. We comment on the implications of our results for these states in the quark gluon plasma. In particular, we estimate the effects of a finite charm quark mass in the dissociation temperature of bottomonium.Comment: 22 pages, 8 figures. Journal version, reference adde

Advanced Pulse Coding Techniques for Distributed Optical Fiber Sensors

Advanced optical pulse coding methods to enhance the performance of distributed optical fiber sensors are reviewed. In particular, the latest implementations dedicated to high-performance long-range Raman and Brillouin based distributed sensing are described

Instanton traces in lattice gluon correlation functions

Strong coupling constant computed in Landau gauge and MOM renormalization scheme from lattice two and three gluon Green Functions exhibits an unexpected behavior in the deep IR, showing a maximum value around $1 {\rm GeV}$. We analise this coupling below this maximum within a semiclassical approach, were gluon degrees of freedom at very low energies are described in terms of the classical solutions of the lagrangian, namely instantons. We provide some new results concerning the relationship between instantons and the low energy dynamics of QCD, by analising gluon two- and three-point Green functions separately and with the help of a cooling procedure to eliminate short range correlations.Comment: 4 pages, talk given at XXXX Rencontres de Moriond on QCD and Hadronic Interactions, La Thuile (Italy

Modified instanton profile effects from lattice Green functions

We trace here instantons through the analysis of pure Yang-Mills gluon Green functions in the Landau gauge for a window of IR momenta (0.4 GeV $< k < 0.9$ GeV). We present lattice results that can be fitted only after substituting the BPST profile in the Instanton liquid model (ILM) by one based on the Diakonov and Petrov variational methods. This also leads us to gain information on the parameters of ILM.Comment: 32 pagex, 6 figure

A Ghost Story II: Ghosts, Gluons and the Gluon condensate beyond the IR of QCD

Beyond the deep IR, the analysis of ghost and gluon propagators still keeps very interesting non-perturbative information. The Taylor-scheme coupling can be computed and applied to obtain the $\Lambda_{\rm QCD}$ parameter from Landau gauge lattice simulations. Furthermore, a dimension-two gluon condensate, that can be understood in the instanton liquid model, plays an important role in the game.Comment: 12 pp., 3 fig

Pratiques funéraires du second âge du Fer en Gaule de l'Ouest (Bretagne, Pays de la Loire, Poitou-Charentes)

International audienceHallstatt and La Tène funeraries practicies in Brittany, Loire countries and Western-Central FranceBilan des pratiques funéraires de l'Armorique au centre-Ouest de la France pendant le premier et le second âge du fe

An Instanton Picture O.P.E. <A^2> Condensate?

Gluon two- and three-point Green Functions computed in Landau gauge from the lattice show the existence of power corrections to the purely perturbative expressions, that can be explained through an Operator Product Expansion as the influence of a non gauge invariant mass dimension two condensate. The relationship of this condensate with topological properties of QCD, namely instantons, will be studied, giving a first estimate of the contribution of instantons to this condensate based in the direct lattice measure, after a cooling process, of the instanton liquid properties.Comment: Lattice2002(topology) contribution, 3 pages, 2 figure

Novel Concepts and Recent Progress in Distributed Optical Fiber Sensing

Recent techniques open new perspectives for distributed fiber sensing. Pulse coding and multi-dimensional denoising methods result in a >10 dB noise reduction with minor modifications of the experimental layout