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CP violation in the effective action of the Standard ModelMar 31 2009Jun 16 2009Following a suggestion by Smit, the CP odd terms of the effective action of the Standard Model, obtained by integration of quarks and leptons, are computed to sixth order within a strict covariant derivative expansion approach. No other approximations ... More

Double $Λ$ Hypernuclei and the Nuclear Medium Effective $ΛΛ$ InteractionJan 29 1998Dec 16 1998We fit the $^1 S_0 \Lambda\Lambda$ interaction in the nuclear medium to the masses of the experimentally known double-$\Lambda$ hypernuclei: $^{\phantom{6}6}_{\Lambda\Lambda}$He, $^{10}_{\Lambda\Lambda}$Be and $^{13}_{\Lambda\Lambda}$B. We derive this ... More

The perturbative scalar massless propagator in Schwarzschild spacetimeMar 26 2013A short derivation is given of the weak gravitational field approximation to the scalar massless propagator in Schwarzschild spacetime obtained by Paszko using the path-integral approach. The contribution from the direct coupling of the quantum field ... More

SU(6)$\supset$SU(3)xSU(2) and SU(8)$\supset$SU(4)xSU(2) Clebsch-Gordan coefficientsOct 27 2010Tables of scalar factors are presented for 63x63 and 120x63 in SU(8)$\supset$SU(4)xSU(2), and for 35x35 and 56x35 in SU(6)$\supset$SU(3)xSU(2). Related tables for SU(4)$\supset$SU(3)xU(1) and SU(3)$\supset$SU(2)xU(1) are also provided so that the Clebsch-Gordan ... More

Renormalization of vector fields with mass-like coupling in curved spacetimeApr 12 2019Using the method of covariant symbols we compute the divergent part of the effective action of the Proca field with non-minimal mass term. Specifically a quantum Abelian vector field with a non-derivative coupling to an external tensor field in curved ... More

$K^-$-Nucleus Scattering at Low and Intermediate EnergiesOct 09 2002Feb 21 2003We calculate $K^-$-nucleus elastic differential, reaction and total cross sections for different nuclei ($^{12}$C,$^{40}$Ca and $^{208}$Pb) at several laboratory antikaon momenta, ranging from 127 MeV to 800 MeV. We use different antikaon-nucleus optical ... More

SU(6) Extension of the Weinberg-Tomozawa Meson-Baryon LagrangianMay 27 2005May 11 2006A consistent SU(6) extension of the Weinberg-Tomozawa meson-baryon chiral Lagrangian is constructed which incorporates vector meson and baryon decuplet degrees of freedom. The corresponding Bethe-Salpeter approximation predicts the existence of an isoscalar ... More

Quasielastic K-nucleus scatteringAug 08 1996Mar 10 1997Quasielastic K^+ - nucleus scattering data at q=290, 390 and 480 MeV/c are analyzed in a finite nucleus continuum random phase approximation framework, using a density-dependent particle-hole interaction. The reaction mechanism is consistently treated ... More

Optical Potentials in Kaonic AtomsSep 18 2001Sep 27 2001A microscopic optical potential based on a chiral model is used as a starting point for studying kaonic atoms levels. We add to this potential a phenomenological part fitted to the experimentally known shifts and widths of kaonic levels. This fitted potential ... More

D^- mesic atomsNov 28 2011The anti-D meson self-energy is evaluated self-consistently, using unitarized coupled-channel theory, by computing the in-medium meson-baryon T-matrix in the C=-1,S=0 sector. The heavy pseudo-scalar and heavy vector mesons, anti-D and anti-D^*, are treated ... More

Large $N$ Weinberg-Tomozawa interaction and spin-flavor symmetryOct 17 2006The construction of an extended version of the Weinberg-Tomozawa Lagrangian, in which baryons and mesons form spin-flavor multiplets, is reviewed and some of its properties discussed, for an arbitrary number of colors and flavors. The coefficient tables ... More

$η$ bound states in nucleiJun 11 2002The energies and widths of bound states of the $\eta$ meson in different nuclei are obtained using the results for its selfenergy in a nuclear medium, which is evaluated in a selfconsistent manner using techniques of unitarized chiral perturbation theory. ... More

Odd Parity Light Baryon ResonancesApr 14 2011Sep 14 2011We use a consistent SU(6) extension of the meson-baryon chiral Lagrangian within a coupled channel unitary approach in order to calculate the T-matrix for meson-baryon scattering in s-wave. The building blocks of the scheme are the pion and nucleon octets, ... More

Large Nc Weinberg-Tomozawa interaction and negative parity s--wave baryon resonancesMay 05 2006Jul 14 2006It is shown that in the 70 and 700 SU(6) irreducible spaces, the SU(6) extension of the Weinberg-Tomozawa (WT) s-wave meson-baryon interaction incorporating vector mesons ({\it hep-ph/0505233}) scales as ${\cal O}(N_c^0)$, instead of the well known ${\cal ... More

Non-localities and Fermi motion corrections in $K^-$ atomsDec 20 2000Oct 17 2001We evaluate the p-wave $K^-N$ amplitudes from the chiral Lagrangians and from there construct the p-wave part of the $K^-$ nucleus optical potential plus a small s-wave part induced from the elementary p-wave amplitude and the nuclear Fermi motion. Simultaneously, ... More

Compositeness of the strange, charm and beauty odd parity $Λ$ statesJun 13 2015We study the dependence on the quark mass of the compositeness of the lowest-lying odd parity hyperon states. Thus, we pay attention to $\Lambda-$like states in the strange, charm and beauty, sectors which are dynamically generated using a unitarized ... More

Odd parity bottom-flavored baryon resonancesOct 17 2012Feb 05 2013The LHCb Collaboration has recently observed two narrow baryon resonances with beauty. Their masses and decay modes look consistent with the quark model orbitally excited states Lambda_b(5912) and Lambda*_b(5920), with quantum numbers J^P=1/2^- and 3/2^-, ... More

Charmed mesons in nuclei with heavy-quark spin symmetryOct 03 2012We study the properties of charmed pseudoscalar and vector mesons in dense matter within a unitary meson-baryon coupled-channel model which incorporates heavy-quark spin symmetry. This is accomplished by extending the SU(3) Weinberg-Tomozawa Lagrangian ... More

$S=-1$ Meson-Baryon Unitarized Coupled Channel Chiral Perturbation Theory and the $S_{01}-$ $Λ$(1405) and $- Λ$(1670) ResonancesOct 23 2002Feb 20 2003The $s-$wave meson-baryon scattering is analyzed for the strangeness $S=-1$ and isospin I=0 sector in a Bethe-Salpeter coupled channel formalism incorporating Chiral Symmetry. Four channels have been considered: $\pi \Sigma$, $\bar K N$, $\eta \Lambda$ ... More

Charmed hadrons in nuclear mediumDec 15 2009We study the properties of charmed hadrons in dense matter within a coupled-channel approach which accounts for Pauli blocking effects and meson self-energies in a self-consistent manner. We analyze the behaviour in this dense environment of dynamically-generated ... More

Formation spectra of charmed meson--nucleus systems using an antiproton beamDec 10 2015We investigate the structure and formation of charmed meson--nucleus systems, with the aim of understanding the charmed meson--nucleon interactions and the properties of the charmed mesons in the nuclear medium. The $\bar{D}$ mesic nuclei are of special ... More

Hidden charm N and Delta resonances with heavy-quark symmetryFeb 27 2013We develop a model to describe odd parity baryon resonances generated dynamically through a unitary baryon-meson coupled-channels approach. The scheme applies to channels with light and/or heavy quark content. Distinct features of the model are that, ... More

Exotic dynamically generated baryons with negative charm quantum numberFeb 14 2010Following a model based on the $\rm{SU}(8)$ symmetry that treats heavy pseudo-scalars and heavy vector mesons on an equal footing, as required by heavy quark symmetry, we study the interaction of baryons and mesons in coupled channels within an unitary ... More

Charmed baryon resonances with heavy-quark spin symmetryJun 15 2012Charmed baryon resonances that are generated dynamically are studied within a unitary baryon-meson coupled-channel model, which incorporates heavy-quark spin symmetry. The extension of the SU(3) Weinberg-Tomozawa chiral Lagrangian to SU(8) spin-flavor ... More

Meson-Baryon Interactions in Unitarized Chiral Perturbation TheoryNov 29 2002Meson-Baryon Interactions can be successfully described using both Chiral Symmetry and Unitarity. The $s-$wave meson-baryon scattering amplitude is analyzed in a Bethe-Salpeter coupled channel formalism incorporating Chiral Symmetry in the potential. ... More

Heavy meson production in hot dense matterJun 18 2010Sep 22 2010The properties of charmed mesons in dense matter are studied using a unitary coupled-channel approach in the nuclear medium which takes into account Pauli-blocking effects and meson self-energies in a self-consistent manner. We obtain the open-charm meson ... More

Odd-parity dynamically generated baryon resonances with beauty flavorApr 17 2013We study baryon resonances with heavy flavor in a molecular approach, thus as dynamically generated by baryon-meson scattering. This is accomplished by using a unitary coupled-channel model taking, as bare interaction, the extension of the Weinberg-Tomozawa ... More

Photon induced Lambda(1520) production and the role of the K^* exchangeNov 22 2007We study the photon induced Lambda(1520) production in the effective Lagrangian method near threshold, E_\gamma^{LAB}<2 GeV, and in the quark-gluon string model at higher energies 3 GeV < E_\gamma^{LAB} < 5 GeV. In particular, we study the role of the ... More

Leptonic CP violating effective action for Dirac and Majorana neutrinosMay 30 2014In the Standard Model minimally extended to include massive neutrinos, we compute the leading CP-violating zero temperature contributions to the one-loop effective action induced by integration of the leptons. Such contributions start at operators of ... More

Strange and charm mesons at FAIRNov 11 2009We study the properties of strange and charm mesons in hot and dense matter within a self-consistent coupled-channel approach for the experimental conditions of density and temperature expected for the CBM experiment at FAIR/GSI. The in-medium solution ... More

Accelerating dynamical peakons and their behaviourFeb 14 2019Jun 12 2019A wide class of nonlinear dispersive wave equations are shown to possess a novel type of peakon solution in which the amplitude and speed of the peakon are time-dependent. These novel dynamical peakons exhibit a wide variety of different behaviours for ... More

Conservation laws and symmetries of radial generalized nonlinear $p$-Laplacian evolution equationsSep 24 2016Feb 03 2017A class of generalized nonlinear p-Laplacian evolution equations is studied. These equations model radial diffusion-reaction processes in $n\geq 1$ dimensions, where the diffusivity depends on the gradient of the flow. For this class, all local conservation ... More

A general family of multi-peakon equations and their propertiesSep 14 2016Oct 23 2018A general family of peakon equations is introduced, involving two arbitrary functions of the wave amplitude and the wave gradient. This family contains all of the known breaking wave equations, including the integrable ones: Camassa-Holm equation, Degasperis-Procesi ... More

The s-wave charmed baryon resonances from a coupled-channel approach with heavy quark symmetryJul 18 2008Jan 21 2009We study charmed baryon resonances which are generated dynamically within a unitary meson-baryon coupled channel model that treats the heavy pseudoscalar and vector mesons on equal footing as required by heavy-quark symmetry. It is an extension of recent ... More

Conservation laws and symmetries of radial generalized nonlinear $p$-Laplacian evolution equationsSep 24 2016A class of generalized nonlinear p-Laplacian evolution equations is studied. These equations model radial diffusion-reaction processes in $n\geq 1$ dimensions, where the diffusivity depends on the gradient of the flow. For this class, all local conservation ... More

A general family of multi-peakon equationsSep 14 2016A general family of peakon equations is considered, involving two arbitrary functions of the wave amplitude and the wave gradient. This family contains all of the known breaking wave equations, including the integrable ones: Camassa-Holm equation, Degasperis-Procesi ... More

Accelerating dynamical peakons and their behaviourFeb 14 2019A wide class of nonlinear dispersive wave equations are shown to possess a novel type of peakon solution in which the amplitude and speed of the peakon are time-dependent. These novel dynamical peakons exhibit a wide variety of different behaviours for ... More

Conserved norms and related conservation laws for multi-peakon equationsJul 17 2017Nov 27 2017All nonlinear dispersive wave equations in the general class $m_t+f(u,u_x)m+(g(u,u_x)m)_x =0$ are known to possess multi-peakon weak solutions. A classification is presented for families of multi-peakon equations in this class that possess conserved momentum; ... More

Discovery of Blue Hook Stars in the Massive Globular Cluster M54Oct 27 2003Nov 12 2003We present BV photometry centered on the globular cluster M54 (NGC 6715). The color-magnitude diagram clearly shows a blue horizontal branch extending anomalously beyond the zero age horizontal branch theoretical models. These kinds of horizontal branch ... More

Chiral unitary theory: application to nuclear problemsJan 16 2001In this talk we briefly describe some basic elements of chiral perturbation theory, $\chi PT$, and how the implementation of unitarity and other novel elements lead to a better expansion of the $T$ matrix for meson meson and meson baryon interactions. ... More

Gauge invariant derivative expansion of the effective action at finite temperature and density and the scalar field in 2+1 dimensionsJul 24 2000Oct 26 2000A method is presented for the computation of the one-loop effective action at finite temperature and density. The method is based on an expansion in the number of spatial covariant derivatives. It applies to general background field configurations with ... More

Conservation laws and symmetries of a generalized Kawahara equationJan 17 2017The generalized Kawahara equation $u_t=a(t) u_{xxxxx} +b(t)u_{xxx} +c(t)f(u) u_x$ appears in many physical applications. A complete classification of low-order conservation laws and point symmetries is obtained for this equation, which includes as a special ... More

Heavy-quark spin symmetry for charmed and strange baryon resonancesDec 17 2012Jan 18 2013We study charmed and strange baryon resonances that are generated dynamically by a unitary baryon-meson coupled-channels model which incorporates heavy-quark spin symmetry. This is accomplished by extending the SU(3) Weinberg-Tomozawa chiral Lagrangian ... More

Double $Λ$ and the $Λ-Λ$ InteractionNov 18 1997The $\Lambda$-$\Lambda$ effective interaction, in the channel $L=S=0$, in the nuclear medium is fitted to the available binding energies, $B_{\Lambda\Lambda}$, of double $\Lambda$ hypernuclei: $^{6}_{\Lambda\Lambda}$He, $^{10}_{\Lambda\Lambda}$Be and ... More

Conservation laws, symmetries, and line soliton solutions of generalized KP and Boussinesq equations with p-power nonlinearities in two dimensionsOct 07 2017May 23 2018Nonlinear generalizations of integrable equations in one dimension, such as the KdV and Boussinesq equations with $p$-power nonlinearities, arise in many physical applications and are interesting in analysis due to critical behaviour. This paper studies ... More

Heavy mesons in dense matterNov 25 2010Charmed mesons in dense matter are studied within a unitary coupled-channel approach which takes into account Pauli-blocking effects and meson self-energies in a self-consistent manner. We obtain the open-charm meson spectral functions in this dense medium, ... More

Dynamically-generated baryon resonances with heavy flavorMar 18 2014We study baryon resonances with heavy flavor in a molecular approach, thus as dynamically generated by meson-baryon scattering. This is accomplished by using a unitary coupled-channel model taking, as bare interaction, the extension to four flavors and ... More

N and $Δ$ hidden-charm resonances with heavy-quark spin symmetryNov 18 2013We study N and $\Delta$ hidden-charm baryon resonances that are generated dynamically from the s-wave interaction of pseudoscalar and vector mesons with $1/2^+$ and $3/2^+$ baryons. We use a unitary coupled-channels model that fulfills heavy-quark spin ... More

Review of low-energy interaction of strange and charm hadrons with nucleons and nucleiJan 11 2013The properties of strange and charm mesons in nuclear matter and nuclei are reviewed. Different frameworks are presented and discussed paying a special attention to unitarized coupled-channel approaches. Possible experimental signatures of the in-medium ... More

Heavy Hadrons in Dense MatterSep 01 2015We study the behavior of dynamically-generated baryon resonances with heavy-quark content within a unitarized coupled-channel theory in matter that fulfills heavy-quark spin symmetry constraints. We analyze the implications for the formation of charmed ... More

The AMBRE Project: Stellar parameterisation of the ESO:FEROS archived spectraApr 04 2012The AMBRE Project is a collaboration between the European Southern Observatory (ESO) and the Observatoire de la Cote d'Azur (OCA) that has been established in order to carry out the determination of stellar atmospheric parameters for the archived spectra ... More

Fluorine abundances in dwarf stars of the solar neighbourhoodJan 16 2012In spite of many observational efforts aiming to characterize the chemical evolution of our Galaxy, not much is known about the origin of fluorine (F). Models suggest that the F found in the Galaxy might have been produced mainly in three different ways, ... More

The AMBRE project: A new synthetic grid of high-resolution FGKM stellar spectraMay 10 2012Large grids of synthetic spectra covering a widespread range of stellar parameters are mandatory for different stellar and (extra-)Galactic physics applications. Such large grids can be used for the automatic parametrisation of stellar spectra such as ... More

The AMBRE Project: Stellar Parameterisation of the ESO:UVES archived spectraFeb 26 2016The AMBRE Project is a collaboration between the European Southern Observatory (ESO) and the Observatoire de la Cote d'Azur (OCA) that has been established in order to carry out the determination of stellar atmospheric parameters for the archived spectra ... More

The AMBRE project: Iron-peak elements in the solar neighbourhoodDec 22 2016Oct 08 2017The aim of this paper is to characterise the abundance patterns of five iron-peak elements (Mn, Fe, Ni, Cu, and Zn) for which the stellar origin and chemical evolution are still debated. We automatically derived iron peak (Mn, Fe, Ni, Cu, and Zn) and ... More

Quark-mass dependence of baryon resonancesJan 16 2004We study the quark-mass dependence of J^P = \frac12^- s-wave and J^P = \frac32^- d-wave baryon resonances. Parameter-free results are obtained in terms of the leading order chiral Lagrangian. In the 'heavy' SU(3) limit with m_\pi =m_K \simeq 500 MeV the ... More

The lack of binaries among hot horizontal branch stars: M80 and NGC5986Jun 01 2006We present preliminary results of a our search for close (period P < 10 days) binary systems among hot (Teff > 20000 K) horizontal branch stars in globular clusters M80 and NGC5986. We measured radial velocity variations of 11 targets in M80 and 5 in ... More

Low-lying even parity meson resonances and spin-flavor symmetry revisitedApr 03 2013We review and extend the model derived in Phys. Rev. D83 016007 (2011) to address the dynamics of the low-lying even parity meson resonances. This model is based on a coupled channels spin-flavor extension of the chiral Weinberg-Tomozawa Lagrangian. This ... More

Chiral restoration from pionic atoms?Feb 12 2002Jul 08 2002We evaluate widths and shifts of pionic atoms using a theoretical microscopical potential in which the pion decay constant $f_\pi$ is changed by an in--medium density dependent one ($f_\pi(\rho)$), predicted by different partial Chiral restoration calculations. ... More

Pion Cloud Contribution to K+ Nucleus ScatteringJul 29 1994A careful reanalysis is done of the contribution to $K^{+}$ nucleus scattering from the interaction of the kaon with the virtual pion cloud. The usual approximations made in the evaluation of the related kaon selfenergy are shown to fail badly. We also ... More

Deeply bound levels in kaonic atomsJan 31 2000Feb 21 2000Using a microscopic antikaon-nucleus optical potential recently developed by Ramos and Oset (nucl-th/9906016, in print in Nuclear Physics A) from a chiral model, we calculate strong interaction shifts and widths for $K^-$ atoms. This purely theoretical ... More

The AMBRE Project: Parameterisation of FGK-type stars from the ESO:HARPS archived spectraSep 08 2014The AMBRE project is a collaboration between the European Southern Observatory (ESO) and the Observatoire de la Cote d'Azur (OCA). It has been established to determine the stellar atmospheric parameters (effective temperature, surface gravity, global ... More

D mesic nucleiApr 15 2010May 19 2010The energies and widths of several D^0 meson bound states for different nuclei are obtained using a D-meson selfenergy in the nuclear medium, which is evaluated in a selfconsistent manner using techniques of unitarized coupled-channel theory. The kernel ... More

The properties of D and D* mesons in the nuclear mediumMay 29 2009Nov 15 2009We study the properties of $D$ and $D^*$ mesons in nuclear matter within a simultaneous self-consistent coupled-channel unitary approach that implements heavy-quark symmetry. The in-medium solution accounts for Pauli blocking effects, and for the $D$ ... More

Exotic dynamically generated baryons with C$=-$1Oct 28 2010We follow a model based on the SU(8) symmetry for the interaction of mesons with baryons. The model treats on an equal footing the pseudo-scalars and the vector mesons, as required by heavy quark symmetry. The T-matrix calculated within an unitary scheme ... More

Characterisation of the Galactic thin disc with Corot targetsJan 01 2013We use kinematical and chemical properties of 754 Corot stars to characterise the stellar populations of the Milky Way disc in three beams close the Galactic plane. From the atmospheric parameters derived in Gazzano et al. (2010) with the Matisse algorithm, ... More

The lack of close binaries among hot horizontal branch stars in NGC6752Feb 03 2006We present the results of a spectroscopic search for close binaries among horizontal branch (HB) stars in NGC6752. We used the ESO VLT-FORS2 instrument to obtain medium resolution (R=4100) spectra of 51 hot HB stars with 8000 < Teff < 32000 K during four ... More

A lack of close binaries among hot horizontal branch stars in globular clusters - M80 and NGC5986Mar 11 2009Recent investigations have revealed a surprising lack of close binaries among extreme horizontal branch (EHB) stars in the globular cluster NGC6752, at variance with the analogous sdB field stars. Another puzzling result concerns the derived spectroscopic ... More

Spectroscopic search for binaries among EHB stars in globular clustersDec 21 2005We performed a spectroscopic search for binaries among hot Horizontal Branch stars in globular clusters. We present final results for a sample of 51 stars in NGC6752, and preliminary results for the first 15 stars analyzed in M80. The observed stars are ... More

Fluorine in AGB Carbon Stars RevisitedDec 16 2008A reanalysis of the fluorine abundance in three Galactic AGB carbon stars (TX Psc, AQ Sgr and R Scl) has been performed from the molecular HF (1-0) R9 line at 2.3358 $\mu$m. High-resolution (R$\sim 50000$) and high signal to noise spectra obtained with ... More

A nonlinear generalization of the Camassa-Holm equation with peakon solutionsSep 08 2016A nonlinearly generalized Camassa-Holm equation, depending an arbitrary nonlinearity power $p \neq 0$, is considered. This equation reduces to the Camassa-Holm equation when $p=1$ and shares one of the Hamiltonian structures of the Camassa-Holm equation. ... More

Heavy Mesons in Nuclear Matter and NucleiSep 08 2014Heavy mesons in nuclear matter and nuclei are analyzed within different frameworks, paying a special attention to unitarized coupled-channel approaches. Possible experimental signatures of the properties of these mesons in matter are addressed, in particular ... More

Automatic Discovery of Geometry Theorems Using Minimal Canonical Comprehensive Groebner SystemsMar 16 2007Oct 08 2007The main idea in this paper is merging two techniques that have been recently developed. On the one hand, we consider MCCGS, standing for Minimal Canonical Comprehensive Groebner Systems, a recently introduced computational tool yielding "good" bases ... More

Neutrino Masses and Mixing: A Little History for a Lot of FunFeb 12 2019In this talk I present my personal summary of the progress on the determination of the masses of the neutrinos and of the leptonic flavour mixing from the combined analysis of the experimental results.

Anomalous Higgs CouplingsFeb 11 1999We review the effects of new effective interactions on the Higgs boson phenomenology. New physics in the electroweak bosonic sector is expected to induce additional interactions between the Higgs doublet field and the electroweak gauge bosons leading ... More

Limits on Anomalous Couplings from Higgs Boson Production at the TevatronJan 09 1998We estimate the attainable limits on the coefficients of dimension--6 operators from the analysis of Higgs boson phenomenology, in the framework of a $SU_L(2) \times U_Y(1)$ gauge-invariant effective Lagrangian. Our results, based on the data sample already ... More

Reduction of Almost Poisson brackets and Hamiltonization of the Chaplygin SphereAug 06 2008We construct different almost Poisson brackets for nonholonomic systems than those existing in the literature and study their reduction. Such brackets are built by considering non-canonical two-forms on the cotangent bundle of configuration space and ... More

Neutrinos Mass and MixingNov 20 1998I review the status of neutrino masses and mixings in the light of the solar and atmospheric neutrino data. The result from the LSND experiment and the possible role of neutrinos as hot dark matter are also included. I also discuss the simplest schemes ... More

Solutions to the Atmospheric Neutrino ProblemNov 19 1998I summarize here the results of a global fit to the full data set corresponding to 535 days of data of the Super-Kamiokande experiment as well as to all other atmosferic neutrino experiments in order to compare the most likely solutions to the atmospheric ... More

Improving GPS Precision and Processing Time using Parallel and Reduced-Length Wiener FiltersJun 04 2010Increasing GPS precision at low cost has always been a challenge for the manufacturers of the GPS receivers. This paper proposes the use of a Wiener filter for increasing precision in substitution of traditional GPS/INS fusion systems, which require expensive ... More

Integrability of the $n$-dimensional axially symmetric Chaplygin sphereJun 01 2019Jun 08 2019We consider the $n$-dimensional Chaplygin sphere under the assumption that the mass distribution of the sphere is axisymmetric. We prove that for initial conditions whose angular momentum about the contact point is vertical, the dynamics is quasi-periodic. ... More

The AMBRE Project: Constraining the lithium evolution in the Milky WayAug 11 2016The chemical evolution of lithium in the Milky Way represents a major problem in modern astrophysics. Indeed, lithium is, on the one hand, easily destroyed in stellar interiors, and, on the other hand, produced at some specific stellar evolutionary stages ... More

Chiral phase transition and Anderson localization in the Instanton Liquid Model for QCDDec 20 2005We study the spectrum and eigenmodes of the QCD Dirac operator in a gauge background given by an Instanton Liquid Model (ILM) at temperatures around the chiral phase transition. Generically we find the Dirac eigenvectors become more localized as the temperature ... More

Non-standard Neutrino Oscillations at IcecubeDec 19 2006In this talk I review the potential of Icecube for revealing physics beyond the standard model in the oscillation of atmospheric neutrinos.

On the distribution of sparse sequences in prime fields and applicationsAug 25 2010In the present paper we investigate distributional properties of sparse sequences modulo almost all prime numbers. We obtain new results for a wide class of sparse sequences which in particular find applications on additive problems and the discrete Littlewood ... More

Chiral phase transition as an Anderson transition in the Instanton Liquid Model for QCDSep 24 2005We study the spectrum and eigenmodes of the QCD Dirac operator in a gauge background given by an Instanton Liquid Model (ILM) at temperatures around the chiral phase transition. For two massless quark flavors we observe that at the chiral phase transition, ... More

An Overview of the Rotational Behavior of Metal--Poor StarsSep 24 2010The present paper describes the behavior of the rotational velocity in metal--poor stars ([Fe/H]<-0.5 dex) in different evolutionary stages, based on Vsini values from the literature. Our sample is comprised of stars in the field and some Galactic globular ... More

Is the chiral phase transition induced by a metal-insulator transition?Nov 18 2007We investigate the QCD Dirac operator with gauge configurations given by a liquid of instantons in the region of temperatures about the chiral phase transition. Both the quenched and unquenched cases are examined in detail. We present evidence of a localization ... More

The QCD vacuum as a disordered medium: A simplified model for the QCD Dirac operatorDec 12 2003We model the QCD Dirac operator as a power-law random banded matrix (RBM) with the appropriate chiral symmetry. Our motivation is the form of the Dirac operator in a basis of instantonic zero modes with a corresponding gauge background of instantons. ... More

Explaining the lithium ISM decrease at super-solar metallicities in the Solar vicinityFeb 05 2019We propose here that the lithium decrease at super-solar metallicities observed in high resolution spectroscopic surveys can be explained by the interplay of mixed populations, coming from the inner regions of the Milky Way disc. The lower lithium content ... More

The First Fluorine Abundance Determinations in Extragalactic AGB Carbon StarsJul 08 2011Fluorine (19F) abundances (or upper limits) are derived in six extragalactic AGB carbon stars from the HF(1-0) R9 line at 2.3358 mu in high resolution spectra. The stars belong to the Local Group galaxies LMC, SMC and Carina dwarf spheroidal, spanning ... More

Automatic stellar spectra parameterisation in the IR CaII triplet regionSep 28 2011(Abridged) Galactic archaeology aims to determine the evolution of the Galaxy from the chemical and kinematical properties of its stars. The analysis of current large spectroscopic surveys (thousands of stars) and future ones (millions of stars) require ... More

Explaining the decrease in ISM lithium at super-solar metallicities in the solar vicinityFeb 05 2019Mar 12 2019We propose here that the lithium decrease at super-solar metallicities observed in high resolution spectroscopic surveys can be explained by the interplay of mixed populations, coming from the inner regions of the Milky Way disc. The lower lithium content ... More

Meson-Baryon s-wave Resonances with Strangeness -3Oct 26 2006Starting from a consistent SU(6) extension of the Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian (Phys. Rev. D74 (2006) 034025), we study the s-wave meson-baryon resonances in the strangeness S=-3 and negative parity sector. Those resonances are ... More

Quark mass dependence of s-wave baryon resonancesMay 30 2003Dec 16 2003We study the quark mass dependence of $J^P = \frac12^-$ s-wave baryon resonances. Parameter free results are obtained in terms of the leading order chiral Lagrangian. In the 'heavy' SU(3) limit with $m_\pi =m_K \simeq $ 500 MeV the resonances turn into ... More

Resonances and the Weinberg--Tomozawa 56-baryon --35-meson interactionOct 11 2006Nov 16 2006Vector meson degrees of freedom are incorporated into the Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian by using a scheme which relies on spin--flavor SU(6) symmetry. The corresponding Bethe-Salpeter approximation successfully reproduces previous ... More

The Gaia-ESO Survey: properties of newly discovered Li-rich giantsMay 18 2018Jun 05 2018We report 20 new lithium-rich giants discovered within the Gaia-ESO Survey, including the first Li-rich giant with evolutionary stage confirmed by CoRoT data. Atmospheric parameters and abundances were derived in model atmosphere analyses using medium-resolution ... More

Slow decay of cosmic magnetic fields superadiabatically in curvature-torsion scalesJan 24 2014Recently Barrow, and Tsagas [Phys Rev D 77: 107302, (2008)] have shown that slow decay of cosmological magnetic slowly decay in FRW universes on curvature scales as $B\sim{a^{-1}}$ in the context of general relativity (GR). This helps possible amplification ... More

MHD dynamo generation via Riemannian soliton theoryOct 07 2005Heisenberg spin equation equivalence to nonlinear Schr\"{o}dinger equation recently demonstrated by Rogers and Schief, is applied to the investigation of vortex filaments in magnetohydrodynamics (MHD) dynamos. The use of Gauss-Mainard-Codazzi equations ... More

Metric perturbations in Einstein-Cartan CosmologyFeb 07 2002Metric perturbations the stability of solution of Einstein-Cartan cosmology (ECC) are given. The first addresses the stability of solutions of Einstein-Cartan (EC) cosmological model against Einstein static universe background. In this solution we show ... More