total 119766took 0.14s

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

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

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

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

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

$η$ 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

$S=-1$ 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

Low-lying even parity meson resonances and spin-flavor symmetryMay 06 2010Nov 03 2010A study is presented of the $s-$wave meson-meson interactions involving members of the $\rho-$nonet and of the $\pi-$octet. The starting point is an SU(6) spin-flavor extension of the SU(3) flavor Weinberg-Tomozawa Lagrangian. SU(6) symmetry breaking ... 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

Chiral Symmetry and s-wave Low-Lying Meson-Baryon ResonancesMar 14 2003The $s-$wave meson-baryon scattering is analyzed for the isospin-strangeness $I=1/2, S=0$ and $I=0,S=-1$ sectors, in a Bethe-Salpeter coupled channel formalism incorporating Chiral Symmetry. For both sectors, four channels have been considered: $\pi N$, ... More

S=--1 Meson-Baryon Scattering in Coupled Channel Unitarized Chiral Perturbation TheorySep 18 2002The $s-$wave meson-baryon scattering amplitude is analyzed for the strangeness $S=-1$ and isospin I=0 sector in a Bethe-Salpeter coupled channel formalism incorporating Chiral Symmetry. Four two-body channels have been considered: $\bar K N$, $\pi \Sigma ... More

Charmed mesons in nuclear matterJan 14 2010We obtain the properties of charmed mesons in dense matter using a coupled-channel approach which accounts for Pauli blocking effects and meson self-energies in a self-consistent manner. We study the behaviour of dynamically-generated baryonic resonances ... More

Chiral SU(3) Bethe Salpeter Model: Extension to SU(6) and SU(8) Spin-Flavor SymmetriesFeb 12 2008Feb 13 2008Consistent SU(6) and SU(8) spin-flavor extensions of the SU(3) flavor Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian are constructed, which incorporate vector meson degrees of freedom. In the charmless sector, the on-shell approximation to the ... 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

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

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

Charmed baryon resonances with heavy-quark symmetryJun 19 2009We study charmed baryon resonances that are generated dynamically from a coupled-channel unitary approach that implements heavy-quark symmetry. Some states can already be identified with experimental observations, such as $\Lambda_c(2595)$, $\Lambda_c(2660)$, ... 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

Chiral dynamics of hadrons in nucleiJan 25 2005In this talk I report on selected topics of hadron modification in the nuclear medium using the chiral unitary approach to describe the dynamics of the problems. I shall mention how antikaons, $\eta$, and $\phi$ are modified in the medium and will report ... 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

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

Conservation laws and line soliton solutions of a family of modified KP equa tionsFeb 18 2019A family of modified Kadomtsev-Petviashvili equations which includes the integrable case is studied. The explicit line soliton solution and all conservation laws of low order are derived and compared to their counterparts in the integrable case.

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

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

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

Strangeness and Charm in Nuclear MatterNov 30 2012The properties of strange ($K$, $\bar K$ and $\bar K^*$) and open-charm ($D$, $\bar D$ and $D^*$) mesons in dense matter are studied using a unitary approach in coupled channels for meson-baryon scattering. In the strangeness sector, the interaction with ... 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: 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

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

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

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

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

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

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

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

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

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

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

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.

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

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

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

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

Chiral phase transition in lattice QCD as a metal-insulator transitionNov 17 2006Mar 09 2007We investigate the lattice QCD Dirac operator with staggered fermions at temperatures around the chiral phase transition. We present evidence of a metal-insulator transition in the low lying modes of the Dirac operator around the same temperature as the ... 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

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

From globular clusters to the disc: the dual life of our GalaxyNov 12 2018The halo and disc globular cluster population can be used as a tracer of the primordial epochs of the Milky Way formation. In this work, literature data of globular clusters ages, chemical abundances, and structural parameters are studied, explicitly ... 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

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

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

$K^-$-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

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

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

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

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

Metric-torsion preheating: cosmic dynamo mechanism?Dec 29 2014Earlier Bassett et al [Phys Rev D 63 (2001) 023506] investigated the amplification of large scale magnetic fields during preheating and inflation in several different models. They argued that in the presence of conductivity resonance effect is weakened. ... More

Anosov branches of dynamo spectra in one dimensional plasmasMar 12 2010Recently Guenther et al the globally diagonalized ${\alpha}^{2}$ dynamo operator spectrum [J Phys A 2007) in mean field media, and its Krein space related perturbation theory [J Phys A 2006). Earlier, an example of fast dynamos in stretch shear and fold ... More

Josephson current in nanofabricated V/Cu/V mesoscopic junctionsFeb 16 2009Apr 06 2009We report the successful fabrication of planar V/Cu/V mesoscopic Josephson weak-links of different size, and the analysis of their low-temperature behavior. The shorter junctions exhibit critical currents of several tens of microA at 350 mK, while Josephson ... More

The abundance discrepancy problem in HII regionsOct 30 2006The origin of the abundance discrepancy in nebulae is one of the key problems in the physics of photoionized nebulae. In this work we have analized a sample of Galactic and extragalactic H II regions where the abundance discrepancy have been measured, ... More

Revisiting the radial abundance gradients of nitrogen and oxygen of the Milky WayMay 02 2018We present spectra obtained with the 10.4 m Gran Telescopio Canarias telescope of 13 Galactic HII regions, most of them of very low ionisation degree. The objects are located along the Galactic disc, with R_G from 5.7 to 16.1 kpc. We determine T_e([NII]) ... More

Doppler search for exoplanet candidates and binaries in a CoRoT field using a multi-fiber spectrographMar 28 2007Feb 22 2008The discovery of the short-period giant exoplanet population, the so-called hot Jupiter population, and their link to brown dwarfs and low-mass stars challenges the conventional view of planet formation and evolution. We took advantage of the multi-fiber ... More

Stellar characterization of CoRoT/Exoplanet fields with MATISSENov 24 2010The homogeneous spectroscopic determination of the stellar parameters is a mandatory step for transit detections from space. Knowledge of which population the planet hosting stars belong to places constraints on the formation and evolution of exoplanetary ... More

The AMBRE Project: searching for the closest solar siblingsOct 03 2018Oct 08 2018Finding solar siblings, that is, stars that formed in the same cluster as the Sun, will yield information about the conditions at the Sun's birthplace. We search for solar sibling candidates in AMBRE, the very large spectra database of solar vicinity ... More

Topological complexity of subgroups of Artin's braid groupsJul 17 2016Aug 12 2016We consider the topological complexity of subgroups of Artin's braid group consisting of braids whose associated permutations lie in some specified subgroup of the symmetric group. We give upper and lower bounds for the topological complexity of such ... More

Emergence of low noise \emph{frustrated} states in E/I balanced neural networksAug 23 2016We study emerging phenomena in binary neural networks where, with a probability c synaptic intensities are chosen according with a Hebbian prescription, and with probability (1-c) there is an extra random contribution to synaptic weights. This new term, ... More

Topological complexity of unordered configuration spaces of surfacesDec 19 2017Dec 13 2018We determine the topological complexity of unordered configuration spaces on almost all punctured surfaces (both orientable and non-orientable). We also give improved bounds for the topological complexity of unordered configuration spaces on all aspherical ... More

Torsion Gravity Effects on Charged-Particles and Neutron InterferometersNov 04 2001Torsion gravitational effects in the quantum interference of charged particles are investigated. The influence of axial torsion in the Schiff-Banhill effect (SB) inside a metallic shell is given. The effect of torsion on the surface of the earth on (SB) ... More

Crossing the phantom divide in an interacting generalized Chaplygin gasOct 23 2007Jun 09 2008Unified generalized Chaplygin gas models assuming an interaction between dark energy and dark matter fluids have been previously proposed. Following these ideas, we consider a particular relation between dark densities, which allows the possibility of ... More

Towards SDp-brane QuantizationJul 20 2004The quantum mechanical analysis of the canonical hamiltonian description of the effective action of a SDp-brane in bosonic ten dimensional Type II supergravity in a homogeneous background is given. We find exact solutions for the corresponding quantum ... More

Probing the Higgs self-coupling through double Higgs production in vector boson scattering at the LHCJul 25 2018Nov 15 2018In this work we explore the sensitivity to the Higgs self-coupling $\lambda$ in the production of two Higgs bosons via vector boson scattering at the LHC. Although these production channels, concretely $W^+W^- \to HH$ and $ ZZ \to HH$, have lower rates ... 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

Excited Fermion Contribution to Z Physics at One LoopAug 13 1996We investigate the effects induced by excited leptons at the one-loop level in the observables measured on the $Z$ peak at LEP. Using a general effective Lagrangian approach to describe the couplings of the excited leptons, we compute their contributions ... More