Instabilities in two flavor quark matter

I discuss briefly the instabilities of two flavor quark matter, paying attention to the gradient instability which develops in the g2SC phase in the Goldstone $U(1)_A$ sector.Comment: 6 pages. Talk given at QCD@Work07, Martina Franca (Italy). Some typos corrected, one reference adde

Probing Universal Extra Dimensions through rare decays induced by b→sb \to s transition

A few $B_{d,s}$ and $\Lambda_b$ decays induced by $b \to s$ transition are studied in the Standard Model and in the framework of the Appelquist, Cheng and Dobrescu (ACD) model, which is a New Physics scenario where a single universal extra dimension is considered. In particular, we investigate the sensitivity of the observables to the radius $R$ of the compactified extra dimension.Comment: LaTex, 7 pages, 4 eps figures. Contribution to the International Workshop QCD@Work 2007, June 16-20, Martina Franca - Ital

Evading 1/m_b-suppressed IR divergencies in QCDF: Bs-->KK Decays and B_{d,s} mixing

We analyze the deviations of the mixing induced CP asymmetry in B-->phi Ks from sin(2beta), as well as the deviations of the asymmetries in Bs-->K*K*, Bs-->phi K* and Bs-->phi phi from sin(2beta_s), that arise in SM due to penguin pollution. We use a theoretical input which is short-distance dominated in QCD-factorization and thus free of IR-divergencies. We also provide alternative ways to extract angles of the unitarity triangle from penguin-mediated decays, and give predictions for Bs-->K*K* observables.Comment: 5 pages. Talk given at the International Workshop on Quantum Chromodynamics: QCD@Work 2007, Martina Franca, Italy, June 200

Instabilities in two flavor quark matter

I discuss briefly the instabilities of two flavor quark matter, paying attention to the gradient instability which develops in the g2SC phase in the Goldstone $U(1)_A$ sector.Comment: 6 pages. Talk given at QCD@Work07, Martina Franca (Italy). Some typos corrected, one reference adde

Possible crossover from BCS superconductivity to Bose-Einstein condensate in quark matter

The possibility of the crossover from the BCS pairing to the Bose-Einstein condensate (BEC) of diquarks with going down in density is discussed in the framework of in the Nambu Jona-Lasinio (NJL) model. We find that the quark matter at moderate density may be close to the intermediate of the crossover, the precursory regime to the BEC phase.Comment: 6 pages, 4 figures, Contributed to International Workshop on Quantum Chromodynamics: QCD@Work 2007, Martina Franca, Valle d'Itria, Italy, 16-20 Jun 200

Chiral Lagrangians with tensor sources

The implementation of tensor sources in Chiral Lagrangians allows the computation of Green functions and form factors involving tensor currents, that is, quark bilinears of the form \bar{q}_i\sigma^{\mu\nu}q_j. Whereas only four new terms show up at O(p^4), we find around a hundred of them at O(p^6). So it becomes essential to ensure that this set o operators is indeed minimal and non-redundant (i.e., it is a basis). We discuss two phenomenological applications in the context of vector meson resonances and the radiative pion decay.Comment: Talk given at the 4th International Worshop on Quantum ChromoDynamics, Theory and experiment, June 16-20, 2007. Martina Franca - Valle d'Itria - Ital

Chromomagnetic Instability and Gluonic Phase at Nonzero Temperature

We describe the results of recent studies of a chromomagnetic instability and a gluonic phase in neutral two-flavor quark matter at nonzero temperature.Comment: 6 pages, 3 figures, prepared for International Workshop on Quantum Chromodynamics: QCD@Work 2007, Martina Franca, Valle d'Itria, Italy, 16-20 Jun 200

Hadronic decays of the tau lepton into K K pion modes within Resonance Chiral Theory

Tau decays into hadrons have a twofold interest: On the one hand, they are a clean environment for studying the hadronization of the left-handed current of QCD, while, on the other side, provide relevant dynamical information of the resonances that mediate these processes. Within an effective field theory-like framework, namely Resonance Chiral Theory, we analyse the decays ot the tau into K K pion modes and compare the results with CLEO and BaBar data. In this way, we provide bounds on the couplings entering our Lagrangian and predict the corresponding spectral functions. As a main result -and contrary to the bulk of theoretical studies and experimental analyses- we find vector current dominance on these decays.Comment: 7 pages, 1 figure, Prepared for the conference QCD@Work07 in Martina Franca, Bari, Italy. To appear in the Proceeding

Holographic description of glueballs in a deformed AdS-dilaton background

We investigate the mass spectra of scalar and vector glueballs in the so-called bottom-up approach of the AdS/QCD correspondence. The holographic model of QCD includes a static dilaton background field. We study the constraints on the masses coming from perturbing the dilaton field and the geometry of the bulk.Comment: Talk given at the International Workshop on Quantum Chromodynamics: QCD@Work 2007, Martina Franca, Italy, 16-20 June 200

Determining chiral couplings at NLO

We present a general method that allows to estimate the low-energy constants of Chiral Perturbation Theory up to next-to-leading corrections in the 1/N(C) expansion, that is, keeping full control of the renormalization scale dependence. As a first step we have determined L(8) and C(38), the couplings related to the difference of the two-point correlation functions of two scalar and pseudoscalar currents, L(8)(mu_0) = (0.6 \pm 0.4) 10^{-3} and C(38)(mu_0) = (2 \pm 6) 10^{-6}$, with mu_0 = 0.77 GeV. As in many effective approaches, one of the main ingredients of this method is the matching procedure: some comments related to this topic are presented here.Comment: Talk given at the International Workshop on Quantum Chromodynamics QCD@work 2007, 16th-20th June (2007), Martina Franca (Italy). 6 p