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Author Oset, E.; Albaladejo, M.; Xie, J.J.; Ramos, A. url  doi
openurl 
  Title Recent developments on hadron interaction and dynamically generated resonances Type Journal Article
  Year 2014 Publication International Journal of Modern Physics E Abbreviated Journal Int. J. Mod. Phys. E  
  Volume 23 Issue 7 Pages (down) 1461008 - 8pp  
  Keywords Hadron interaction; dynamically generated resonances  
  Abstract In this talk I report on the recent developments in the subject of dynamically generated resonances. In particular I discuss the gamma p -> K-0 Sigma+ and gamma n -> K-0 Sigma(0) reactions, with a peculiar behavior around the K*(0)Lambda threshold, due to a 1/2(-) resonance around 2035 MeV. Similarly, I discuss a BES experiment, J/psi -> eta K*(0) (K) over bar*(0) decay, which provides evidence for a new h(1) resonance around 1830 MeV that was predicted from the vector-vector interaction. A short discussion is then made about recent advances in the charm and beauty sectors.  
  Address [Oset, E.; Albaladejo, M.; Ramos, A.] Univ Valencia, Inst Invest Paterna, Ctr Mixto, Dept Fis Teor,CSIC, Valencia 46071, Spain, Email: oset@ific.uv.es  
  Corporate Author Thesis  
  Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0218-3013 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000341934000009 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1946  
Permanent link to this record
 

 
Author Oset, E.; Ramos, A.; Garzon, E.J.; Molina, R.; Tolos, L.; Xiao, C.W.; Wu, J.J.; Zou, B.S. url  doi
openurl 
  Title Interaction of vector mesons with baryons and nuclei Type Journal Article
  Year 2012 Publication International Journal of Modern Physics E Abbreviated Journal Int. J. Mod. Phys. E  
  Volume 21 Issue 11 Pages (down) 1230011 - 18pp  
  Keywords Vector-baryon interaction; vectors in medium; J/psi suppression in nuclei  
  Abstract After some short introductory remarks on particular issues on the vector mesons in nuclei, in this paper, we present a short review of recent developments concerning the interaction of vector mesons with baryons and with nuclei from a modern perspective using the local hidden gauge formalism for the interaction of vector mesons. We present results for the vector-baryon interaction and in particular for the resonances which appear as composite states, dynamically generated from the interaction of vector mesons with baryons, taking also the mixing of these states with pseudoscalars and baryons into account. We then venture into the charm sector, reporting on hidden charm baryon states around 4400 MeV, generated from the interaction of vector mesons and baryons with charm, which have a strong repercussion on the properties of the J/Psi N interaction. We also address the interaction of K* with nuclei and make suggestions to measure the predicted huge width in the medium by means of transparency ratio. The formalism is extended to study the phenomenon of J/psi suppression in nuclei via J/psi photo-production reactions.  
  Address [Oset, E.; Garzon, E. J.; Xiao, C. W.] Univ Valencia, CSIC, Inst Invest Paterna, Dept Fis Teor, Valencia 46071, Spain, Email: oset@ific.uv.es  
  Corporate Author Thesis  
  Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0218-3013 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000310855800002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1204  
Permanent link to this record
 

 
Author Hernandez, P.; Pena, C.; Ramos, A.; Gomez-Cadenas, J.J. url  doi
openurl 
  Title A new formulation of compartmental epidemic modelling for arbitrary distributions of incubation and removal times Type Journal Article
  Year 2021 Publication Plos One Abbreviated Journal PLoS One  
  Volume 16 Issue 2 Pages (down) e0244107 - 22pp  
  Keywords  
  Abstract The paradigm for compartment models in epidemiology assumes exponentially distributed incubation and removal times, which is not realistic in actual populations. Commonly used variations with multiple exponentially distributed variables are more flexible, yet do not allow for arbitrary distributions. We present a new formulation, focussing on the SEIR concept that allows to include general distributions of incubation and removal times. We compare the solution to two types of agent-based model simulations, a spatially homogeneous one where infection occurs by proximity, and a model on a scale-free network with varying clustering properties, where the infection between any two agents occurs via their link if it exists. We find good agreement in both cases. Furthermore a family of asymptotic solutions of the equations is found in terms of a logistic curve, which after a non-universal time shift, fits extremely well all the microdynamical simulations. The formulation allows for a simple numerical approach; software in Julia and Python is provided.  
  Address [Hernandez, Pilar] Univ Valencia, Dept Fis Teor, Valencia, Spain, Email: m.pilar.hernandez@uv.es  
  Corporate Author Thesis  
  Publisher Public Library Science Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000616739700053 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4750  
Permanent link to this record
 

 
Author Dorigo, T. et al; Ramos, A.; Ruiz de Austri, R. url  doi
openurl 
  Title Toward the end-to-end optimization of particle physics instruments with differentiable programming Type Journal Article
  Year 2023 Publication Reviews in Physics Abbreviated Journal Rev. Phys.  
  Volume 10 Issue Pages (down) 100085 - pp  
  Keywords  
  Abstract The full optimization of the design and operation of instruments whose functioning relies on the interaction of radiation with matter is a super-human task, due to the large dimensionality of the space of possible choices for geometry, detection technology, materials, data-acquisition, and information-extraction techniques, and the interdependence of the related parameters. On the other hand, massive potential gains in performance over standard, “experience-driven” layouts are in principle within our reach if an objective function fully aligned with the final goals of the instrument is maximized through a systematic search of the configuration space. The stochastic nature of the involved quantum processes make the modeling of these systems an intractable problem from a classical statistics point of view, yet the construction of a fully differentiable pipeline and the use of deep learning techniques may allow the simultaneous optimization of all design parameters.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 6096  
Permanent link to this record
 

 
Author Feijoo, A.; Magas, V.K.; Ramos, A.; Oset, E. url  doi
openurl 
  Title Lambda(b) -> J/psi K Xi decay and the higher order chiral terms of the meson baryon interaction Type Journal Article
  Year 2015 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 92 Issue 7 Pages (down) 076015 - 10pp  
  Keywords  
  Abstract We study the weak decay of the Lambda(b) into J/psi K Xi. and J/psi eta Lambda states, and relate these processes to the Lambda(b) -> J/psi(K) over barN decay mode. The elementary weak transition at the quark level proceeds via the creation of a J/psi meson and an excited sud system with I = 0, which upon hadronization leads to (K) over barN or eta Lambda pairs. These states undergo final-state interaction in coupled channels and produce a final meson-baryon pair. The K. state only occurs via rescattering, hence making the Lambda(b) -> J/psi K Xi process very sensitive to the details of the meson-baryon interaction in strangeness S = -1 and isospin I = 0. We show that the corresponding invariant mass distribution is dominated by the next-to-leading-order terms of the chiral interaction. The I = 0 selectivity of this decay, and its large sensitivity to the higher-order terms, makes its measurement very useful and complementary to the K- p -> K Xi cross section data. The rates of the Lambda(b) -> J/psi K Xi and Lambda(b) -> J/psi eta Lambda invariant mass distributions are sizable compared to those of the Lambda(b) -> J/psi(K) over barN decay, which is measured experimentally, and thus, we provide arguments for an experimental determination of these decay modes that will help us understand better the chiral dynamics at higher energies.  
  Address [Feijoo, A.; Magas, V. K.; Ramos, A.] Univ Barcelona, Dept Estruct & Constituents Mat, E-08028 Barcelona, Spain, Email: feijoo@ecm.ub.edu  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1550-7998 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000363792600009 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 2432  
Permanent link to this record
 

 
Author Tolos, L.; Molina, R.; Oset, E.; Ramos, A. url  doi
openurl 
  Title (K)over-bar* mesons in dense matter Type Journal Article
  Year 2010 Publication Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 82 Issue 4 Pages (down) 045210 - 12pp  
  Keywords  
  Abstract We study the properties of (K) over bar* mesons in nuclear matter using a unitary approach in coupled channels within the framework of the local hidden gauge formalism and incorporating the (K) over bar pi decay channel in matter. The in-medium (K) over bar *N interaction accounts for Pauli blocking effects and incorporates the (K) over bar* self-energy in a self-consistent manner. We also obtain the (K) over bar* (off-shell) spectral function and analyze its behavior at finite density and momentum. At a normal nuclear matter density, the (K) over bar* meson feels a moderately attractive potential, while the (K) over bar* width becomes five times larger than in free space. We estimate the transparency ratio of the gamma A -> K+K*(-) A` reaction, which we propose as a feasible scenario at the present facilities to detect changes in the properties of the (K) over bar* meson in nuclear medium.  
  Address [Tolos, L.] Univ Groningen, Theory Grp KVI, NL-9747 AA Groningen, Netherlands, Email: tolos@kvi.nl  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000283648400011 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 335  
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Author Magas, V.K.; Yamagata-Sekihara, J.; Hirenzaki, S.; Oset, E.; Ramos, A. url  doi
openurl 
  Title Proton emission off nuclei induced by kaons in flight Type Journal Article
  Year 2010 Publication Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 81 Issue 2 Pages (down) 024609 - 10pp  
  Keywords  
  Abstract We study the (K-, p) reaction on nuclei with a 1 GeV/c momentum kaon beam, paying special attention to the region of emitted protons having kinetic energy above 600 MeV, which was used to claim a deeply attractive kaon nucleus optical potential. Our model describes the nuclear reaction in the framework of a local density approach and the calculations are performed following two different procedures: one is based on a many-body method using the Lindhard function and the other is based on a Monte Carlo simulation. The simulation method offers flexibility to account for processes other than kaon quasielastic scattering, such as K- absorption by one and two nucleons, producing hyperons, and allows consideration of final-state interactions of the K-, the p, and all other primary and secondary particles on their way out of the nucleus, as well as the weak decay of the produced hyperons into pi N. We find a limited sensitivity of the cross section to the strength of the kaon optical potential. We also show a serious drawback in the experimental setup-the requirement for having, together with the energetic proton, at least one charged particle detected in the decay counter surrounding the target-as we find that the shape of the original cross section is appreciably distorted, to the point of invalidating the claims made in the experimental paper on the strength of the kaon nucleus optical.  
  Address [Magas, V. K.; Ramos, A.] Univ Barcelona, Dept Estructura & Constituents Mat, E-08028 Barcelona, Spain, Email: vladimir@ecm.ub.es  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000278341300014 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 432  
Permanent link to this record
 

 
Author Feijoo, A.; Gazda, D.; Magas, V.; Ramos, A. url  doi
openurl 
  Title The (K)over-barN Interaction in Higher Partial Waves Type Journal Article
  Year 2021 Publication Symmetry-Basel Abbreviated Journal Symmetry-Basel  
  Volume 13 Issue 8 Pages (down) 1434 - 22pp  
  Keywords chiral Lagrangian; unitarization; resonances; (K)over-barN interaction  
  Abstract We present a chiral (K) over barN interaction model that has been developed and optimized in order to account for the experimental data of inelastic (K) over barN reaction channels that open at higher energies. In particular, we study the effect of the higher partial waves, which originate directly from the chiral Lagrangian, as they could supersede the role of high-spin resonances employed in earlier phenomenological models to describe meson-baryon cross sections in the 2 GeV region. We present a detailed derivation of the partial wave amplitudes that emerge from the chiral SU(3) meson-baryon Lagrangian up to the d-waves and next-to-leading order in the chiral expansion. We implement a nonperturbative unitarization in coupled channels and optimize the model parameters to a large pool of experimental data in the relevant energy range where these new contributions are expected to be important. The obtained results are encouraging. They indicate the ability of the chiral higher partial waves to extend the description of the scattering data to higher energies and to account for structures in the reaction cross-sections that cannot be accommodated by theoretical models limited to the s-waves.  
  Address [Feijoo, Albert] Ctr Mixto CSIC UV, Inst Fis Corpuscular, Inst Invest Paterna, Apartados 22085, Valencia 46071, Spain, Email: edfeijoo@ific.uv.es;  
  Corporate Author Thesis  
  Publisher Mdpi Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000689831200001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4948  
Permanent link to this record
 

 
Author Gross, F. et al; Ramos, A.; Vos, M. url  doi
openurl 
  Title 50 Years of quantum chromodynamics Type Journal Article
  Year 2023 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C  
  Volume 83 Issue 12 Pages (down) 1125 - 636pp  
  Keywords  
  Abstract Quantum Chromodynamics, the theory of quarks and gluons, whose interactions can be described by a local SU(3) gauge symmetry with charges called “color quantum numbers”, is reviewed; the goal of this review is to provide advanced Ph.D. students a comprehensive handbook, helpful for their research. When QCD was “discovered” 50 years ago, the idea that quarks could exist, but not be observed, left most physicists unconvinced. Then, with the discovery of charmonium in 1974 and the explanation of its excited states using the Cornell potential, consisting of the sum of a Coulomb-like attraction and a long range linear confining potential, the theory was suddenly widely accepted. This paradigm shift is now referred to as the November revolution. It had been anticipated by the observation of scaling in deep inelastic scattering, and was followed by the discovery of gluons in three-jet events. The parameters of QCD include the running coupling constant, as (Q(2)), that varies with the energy scale Q(2) characterising the interaction, and six quark masses. QCD cannot be solved analytically, at least not yet, and the large value of alpha(s) at low momentum transfers limits perturbative calculations to the high-energy region where Q(2) >>Lambda(QCD) (2) similar or equal to (250 MeV)(2). Lattice QCD (LQCD), numerical calculations on a discretized space-time lattice, is discussed in detail, the dynamics of the QCD vacuum is visualized, and the expected spectra of mesons and baryons are displayed. Progress in lattice calculations of the structure of nucleons and of quantities related to the phase diagram of dense and hot (or cold) hadronic matter are reviewed. Methods and examples of how to calculate hadronic corrections to weak matrix elements on a lattice are outlined. The wide variety of analytical approximations currently in use, and the accuracy of these approximations, are reviewed. Thesemethods range from the Bethe-Salpeter, Dyson-Schwinger coupled relativistic equations, which are formulated in bothMinkowski or Euclidean spaces, to expansions of multi-quark states in a set of basis functions using light-front coordinates, to the AdS/QCD method that imbeds 4-dimensionalQCDin a 5-dimensional deSitter space, allowing confinement and spontaneous chiral symmetry breaking to be described in a novel way. Models that assume the number of colors is very large, i.e. make use of the large Nclimit, give unique insights. Many other techniques that are tailored to specific problems, such as perturbative expansions for high energy scattering or approximate calculations using the operator product expansion are discussed. The very powerful effective field theory techniques that are successful for low energy nuclear systems (chiral effective theory), or for non-relativistic systems involving heavy quarks, or the treatment of gluon exchanges between energetic, collinear partons encountered in jets, are discussed. The spectroscopy of mesons and baryons has played an important historical role in the development of QCD. The famous X,Y,Z states – and the discovery of pentaquarks – have revolutionized hadron spectroscopy; their status and interpretation are reviewed as well as recent progress in the identification of glueballs and hybrids in light-meson spectroscopy. These exotic states add to the spectrum of expected q ($) over barq mesons and qqq baryons. The progress in understanding excitations of light and heavy baryons is discussed. The nucleon as the lightest baryon is discussed extensively, its form factors, its partonic structure and the status of the attempt to determine a three-dimensional picture of the parton distribution. An experimental program to study the phase diagram of QCD at high temperature and density started with fixed target experiments in various laboratories in the second half of the 1980s, and then, in this century, with colliders. QCD thermodynamics at high temperature became accessible to LQCD, and numerical results on chiral and deconfinement transitions and properties of the deconfined and chirally restored form of strongly interacting matter, called the Quark-Gluon Plasma (QGP), have become very precise by now. These results can now be confronted with experimental data that are sensitive to the nature of the phase transition. There is clear evidence that the QGP phase is created. This phase of QCD matter can already be characterized by some properties that indicate, within a temperature range of a few times the pseudocritical temperature, the medium behaves like a near ideal liquid. Experimental observables are presented that demonstrate deconfinement. High and ultrahigh density QCD matter at moderate and low temperatures shows interesting features and new phases that are of astrophysical relevance. They are reviewed here and some of the astrophysical implications are discussed. Perturbative QCD and methods to describe the different aspects of scattering processes are discussed. The primary partonparton scattering in a collision is calculated in perturbative QCD with increasing complexity. The radiation of soft gluons can spoil the perturbative convergence, this can be cured by resummation techniques, which are also described here. Realistic descriptions of QCD scattering events need to model the cascade of quark and gluon splittings until hadron formation sets in, which is done by parton showers. The full event simulation can be performed with Monte Carlo event  
  Address [Gross, Franz; Burkert, Volker D.; Orginos, Kostas; Deur, Alexandre; Dudek, Jozef; Grube, Boris; Melnitchouk, Wally; Qiu, Jianwei; Rossi, Patrizia; Weiss, Christian] Thomas Jefferson Natl Accelerator Facil, 12000 Jefferson Ave, Newport News, VA 23606 USA, Email: klempt@hiskp.uni-bonn.de  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6044 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001124298200001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5859  
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Author Dalla Brida, M.; Hollwieser, R.; Knechtli, F.; Korzec, T.; Nada, A.; Ramos, A.; Sint, S.; Sommer, R. url  doi
openurl 
  Title Determination of a(s )(mZ) by the non-perturbative decoupling method Type Journal Article
  Year 2022 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C  
  Volume 82 Issue 12 Pages (down) 1092 - 38pp  
  Keywords  
  Abstract We present the details and first results of a new strategy for the determination of alpha s(mZ) (ALPHA Collaboration et al. in Phys. Lett. B 807:135571, 2020). By simultaneously decoupling 3 fictitious heavy quarks we establish a relation between the A-parameters of three-flavor QCD and pure gauge theory. Very precise recent results in the pure gauge theory (Dalla Brida and Ramos in Eur. Phys. J. C 79(8):720, 2019; Nada and Ramos in Eur Phys J C 81(1):1, 2021) can thus be leveraged to obtain the three flavour A-parameter in units of a common decoupling scale. Connecting this scale to hadronic physics in 3-flavour QCD leads to our result in physical units, A(3)/MS = 336(12) MeV, which translates to alpha s(m(Z)) = 0.11823(84). This is compatible with both the FLAG average (Aoki et al. in FLAG review 2021. arXiv:2111.09849 [hep-lat]) and the previous ALPHA result (ALPHA Collaboration et al., Phys. Rev. Lett. 119(10):102001, 2017), with a comparable, yet still statistics dominated, error. This constitutes a highly non-trivial check, as the decoupling strategy is conceptually very different from the 3-flavour QCD step-scaling method, and so are their systematic errors. These include the uncertainties of the combined decoupling and continuum limits, which we discuss in some detail. We also quantify the correlation between both results, due to some common elements, such as the scale determination in physical units and the definition of the energy scale where we apply decoupling.  
  Address [Dalla Brida, Mattia] CERN, Theoret Phys Dept, CH-1211 Geneva 23, Switzerland, Email: alberto.ramos@ific.uv.es  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6044 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000893933600003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5448  
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