|
Records |
Links |
|
Author |
Mantovani Sarti, V.; Feijoo, A.; Vidana, I.; Ramos, A.; Giacosa, F.; Hyodo, T.; Kamiya, Y. |
|
|
Title |
Constraining the low-energy S =-2 meson-baryon interaction with two-particle correlations |
Type |
Journal Article |
|
Year |
2024 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
|
|
Volume |
110 |
Issue |
1 |
Pages |
L011505 - 8pp |
|
|
Keywords |
|
|
|
Abstract |
In this paper we present a novel method to extract information on hadron-hadron interactions using for the first time femtoscopic data to constrain the low-energy constants of a QCD effective Lagrangian. This method offers a new way to investigate the nonperturbative regime of QCD in sectors where scattering experiments are not feasible, such as the multistrange and charm ones. As an example of its application, we use the very precise K-Lambda correlation function data, recently measured in pp collisions at LHC, to constrain the strangeness S = -2 meson-baryon interaction. The model obtained delivers new insights on the molecular nature of the Xi(1620) and Xi(1690) states. |
|
|
Address |
[Sarti, V. Mantovani] Tech Univ Munich, Phys Dept E62, Garching, Germany, Email: valentina.mantovani-sarti@tum.de; |
|
|
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 |
2470-0010 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:001285579200004 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
6227 |
|
Permanent link to this record |
|
|
|
|
Author |
Oset, E.; Ramos, A. |
|
|
Title |
Chiral unitary approach to eta ' N scattering at low energies |
Type |
Journal Article |
|
Year |
2011 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
|
|
Volume |
704 |
Issue |
4 |
Pages |
334-342 |
|
|
Keywords |
|
|
|
Abstract |
We study the eta'N interaction within a chiral unitary approach which includes pi N, eta N and related pseudoscalar meson-baryon coupled channels. Since the SU(3) singlet does not contribute to the standard interaction and the eta' is mostly a singlet, the resulting scattering amplitude is very small and inconsistent with the experimental scattering length. The additional consideration of vector meson-baryon states into the coupled channel scheme, via normal and anomalous couplings of pseudoscalar to vector mesons, enhances substantially the eta'N amplitude. We also exploit the freedom of adding to the Lagrangian a new term, allowed by the symmetries of QCD, which couples baryons to the singlet meson of SU(3). Adjusting the unknown strength to the eta'N scattering length, we obtain predictions for the elastic eta'N -> eta'N and inelastic eta'N -> eta N, pi N, K Lambda, K Sigma cross sections at low eta' energies, and discuss their significance. |
|
|
Address |
[Ramos, A] Univ Barcelona, Dept Estruct & Constituents Mat, E-08028 Barcelona, Spain, Email: ramos@ecm.ub.es |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0370-2693 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000296175500015 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
no |
|
|
Call Number |
IFIC @ elepoucu @ |
Serial |
783 |
|
Permanent link to this record |
|
|
|
|
Author |
Nagahiro, H.; Hirenzaki, S.; Oset, E.; Ramos, A. |
|
|
Title |
eta '-Nucleus optical potential and possible eta ' bound states |
Type |
Journal Article |
|
Year |
2012 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
|
|
Volume |
709 |
Issue |
1-2 |
Pages |
87-92 |
|
|
Keywords |
|
|
|
Abstract |
Starting from a recent model of the eta'N interaction, we evaluate the eta'-nucleus optical potential, including the contribution of lowest order in density, t rho/2m(eta'), together with the second-order terms accounting for eta' absorption by two nucleons. We also calculate the formation cross section of the eta' bound states from (pi(+), p) reactions on nuclei. The eta'-nucleus potential suffers from uncertainties tied to the poorly known eta'N interaction, which can be partially constrained by the experimental modulus of the eta'N scattering length and/or the recently measured transparency ratios in eta' nuclear photoproduction. Assuming an attractive interaction and taking the claimed experimental value vertical bar a(eta'N)vertical bar = 0.1 fm, we obtain an eta' optical potential in nuclear matter at saturation density of V eta' = -(8.7 + 1.8i) MeV, not attractive enough to produce eta' bound states in light nuclei. Larger values of the scattering length give rise to deeper optical potentials, with moderate enough imaginary parts. For a value vertical bar a(eta'N)vertical bar = 0.3 fm, which can still be considered to lie within the uncertainties of the experimental constraints, the spectra of light and medium nuclei show clear structures associated to eta'-nuclear bound states and to threshold enhancements in the unbound region. |
|
|
Address |
[Nagahiro, H.; Hirenzaki, S.] Nara Womens Univ, Dept Phys, Nara 6308506, Japan, Email: nagahiro@rcnp.osaka-u.ac.jp |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0370-2693 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000302111200013 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
979 |
|
Permanent link to this record |
|
|
|
|
Author |
Ramos, A.; Oset, E. |
|
|
Title |
The role of vector-baryon channels and resonances in the gamma p -> K-0 Sigma(+) and gamma n -> K-0 Sigma(0) reactions near the K*Lambda threshold |
Type |
Journal Article |
|
Year |
2013 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
|
|
Volume |
727 |
Issue |
1-3 |
Pages |
287-292 |
|
|
Keywords |
|
|
|
Abstract |
We have studied the gamma p -> K-0 Sigma(+) reaction in the energy region around the K*Lambda and K*Sigma thresholds, where the CBELSA/TAPS cross section shows a sudden drop and the differential cross section experiences a transition from a forward-peaked distribution to a flat one. Our coupled-channel model incorporates the dynamics of the vector meson-baryon interaction which is obtained from the hidden gauge formalism. We find that the cross section in this energy region results from a delicate interference between amplitudes having K*Lambda and K*Sigma intermediate states. The sharp downfall is dictated by the presence of a nearby N* resonance produced by our model, a feature that we have employed to predict its properties. We also show results for the complementary gamma n -> K-0 Sigma(0) reaction, the measurement of which would test the mechanism proposed in this work. |
|
|
Address |
[Ramos, A.] Univ Barcelona, Dept Estruct & Constituents Mat, E-08028 Barcelona, Spain, Email: ramos@ecm.ub.edu |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Elsevier Science Bv |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0370-2693 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000328518400041 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
no |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
1681 |
|
Permanent link to this record |
|
|
|
|
Author |
Del Debbio, L.; Ramos, A. |
|
|
Title |
Lattice determinations of the strong coupling |
Type |
Journal Article |
|
Year |
2021 |
Publication |
Physics Reports |
Abbreviated Journal |
Phys. Rep.-Rev. Sec. Phys. Lett. |
|
|
Volume |
920 |
Issue |
|
Pages |
1-71 |
|
|
Keywords |
QCD; Renormalization; Strong coupling; Lattice field theory |
|
|
Abstract |
Lattice QCD has reached a mature status. State of the art lattice computations include u, d, s (and even the c) sea quark effects, together with an estimate of electromagnetic and isospin breaking corrections for hadronic observables. This precise and first principles description of the standard model at low energies allows the determination of multiple quantities that are essential inputs for phenomenology and not accessible to perturbation theory. One of the fundamental parameters that are determined from simulations of lattice QCD is the strong coupling constant, which plays a central role in the quest for precision at the LHC. Lattice calculations currently provide its best determinations, and will play a central role in future phenomenological studies. For this reason we believe that it is timely to provide a pedagogical introduction to the lattice determinations of the strong coupling. Rather than analysing individual studies, the emphasis will be on the methodologies and the systematic errors that arise in these determinations. We hope that these notes will help lattice practitioners, and QCD phenomenologists at large, by providing a self-contained introduction to the methodology and the possible sources of systematic error. The limiting factors in the determination of the strong coupling turn out to be different from the ones that limit other lattice precision observables. We hope to collect enough information here to allow the reader to appreciate the challenges that arise in order to improve further our knowledge of a quantity that is crucial for LHC phenomenology. Crown Copyright & nbsp;(c) 2021 Published by Elsevier B.V. All rights reserved. |
|
|
Address |
[Del Debbio, Luigi] Univ Edinburgh, Sch Phys & Astron, Edinburgh EH9 3JZ, Midlothian, Scotland, Email: luigi.del.debbio@ed.ac.uk; |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0370-1573 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000659901700001 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
4843 |
|
Permanent link to this record |
|
|
|
|
Author |
Hernandez, P.; Pena, C.; Ramos, A.; Gomez-Cadenas, J.J. |
|
|
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 |
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 |
Sekihara, T.; Oset, E.; Ramos, A. |
|
|
Title |
On the structure observed in the in-flight He-3(K-, Lambda p)n reaction at J-PARC |
Type |
Journal Article |
|
Year |
2016 |
Publication |
Progress of Theoretical and Experimental Physics |
Abbreviated Journal |
Prog. Theor. Exp. Phys. |
|
|
Volume |
2016 |
Issue |
12 |
Pages |
123D03 - 27pp |
|
|
Keywords |
|
|
|
Abstract |
A theoretical investigation is done to clarify the origin of the peak structure observed near the K-pp threshold in the in-flight He-3(K-, Lambda p)n reaction of the J-PARC E15 experiment, which could be a signal of the lightest kaonic nuclei, i.e., the (K) over bar NN (I = 1/2) state. For the investigation, we evaluate the Lambda p invariant mass spectrum assuming two possible scenarios to interpret the experimental peak. One assumes that the Lambda (1405) resonance is generated after the emission of an energetic neutron from the absorption of the initial K-, not forming a bound state with the remaining proton. This uncorrelated Lambda (1405)p system subsequently decays into the final Lambda p. The other scenario implies that, after the emission of the energetic neutron, a (K) over bar NN bound state is formed, decaying eventually into a Lambda p pair. Our results show that the experimental signal observed in the in-flight He-3(K-, Lambda p)n reaction at J-PARC is qualitatively well reproduced by the assumption that a (K) over bar NN bound state is generated in the reaction, definitely discarding the interpretation in terms of an uncorrelated Lambda (1405)p s tate. |
|
|
Address |
[Sekihara, Takayasu] Japan Atom Energy Agcy, Adv Sci Res Ctr, Tokai, Ibaraki 3191195, Japan, Email: sekihara@post.j-parc.jp |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Oxford Univ Press Inc |
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2050-3911 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
WOS:000393905400018 |
Approved |
no |
|
|
Is ISI |
yes |
International Collaboration |
yes |
|
|
Call Number |
IFIC @ pastor @ |
Serial |
2954 |
|
Permanent link to this record |
|
|
|
|
Author |
Dorigo, T. et al; Ramos, A.; Ruiz de Austri, R. |
|
|
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 |
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.; Gazda, D.; Magas, V.; Ramos, A. |
|
|
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 |
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 |