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Author (up) Roca, L.; Oset, E.
Title Scattering of unstable particles in a finite volume: The case of pi rho scattering and the a(1)(1260) resonance Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 85 Issue 5 Pages 054507 - 13pp
Keywords
Abstract We present a way to evaluate the scattering of unstable particles quantized in a finite volume with the aim of extracting physical observables for infinite volume from lattice data. We illustrate the method with the pi rho scattering which generates dynamically the axial-vector a(1)(1260) resonance. Energy levels in a finite box are evaluated both considering the rho as a stable and unstable resonance and we find significant differences between both cases. We discuss how to solve the problem to get the physical scattering amplitudes in the infinite volume, and hence phase shifts, from possible lattice results on energy levels quantized inside a finite box.
Address [Roca, L.] Univ Murcia, Dept Fis, E-30071 Murcia, Spain
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:000301706700004 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 941
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Author (up) Roca, L.; Oset, E.
Title Lambda(1405) poles obtained from pi(0)Sigma(0) photoproduction data Type Journal Article
Year 2013 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 87 Issue 5 Pages 055201 - 8pp
Keywords
Abstract We present a strategy to extract the position of the two Lambda(1405) poles from experimental photoproduction data measured recently at different energies in the gamma p -> K+pi(0)Sigma(0) reaction at Jefferson Laboratory. By means of a chiral dynamics motivated potential with free parameters, we solve the Bethe-Salpeter equation in the coupled channels (K) over barN and pi Sigma in isospin I = 0 and parametrize the amplitude for the photonuclear reaction in terms of a linear combination of the pi Sigma -> pi Sigma and (K) over barN -> pi Sigma scattering amplitudes in I = 0, with a different linear combination for each energy. Good fits to the data are obtained with some sets of parameters, by means of which one can also predict the cross section for the K- p -> pi(0)Sigma(0) reaction. These later results help us decide among the possible solutions. The result is that the different solutions lead to two poles similar to those found in the chiral unitary approach. With the best result we find the two Lambda(1405) poles at 1385 – 68i MeV and 1419 – 22i MeV.
Address Univ Murcia, Dept Fis, E-30100 Murcia, Spain
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 WOS:000318527400004 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1442
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Author (up) Roca, L.; Oset, E.
Title Isospin 0 and 1 resonances from pi Sigma photoproduction data Type Journal Article
Year 2013 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 88 Issue 5 Pages 055206 - 7pp
Keywords
Abstract Recently we presented a successful strategy to extract the position of the two Lambda ( 1405) poles from experimental photoproduction data on the gamma p -> K+pi(0)Sigma(0) reaction at Jefferson Lab. Following a similar strategy, we extend the previous method to incorporate also the isospin 1 component which allows us to consider in addition the experimental data on gamma p -> K+pi(+/-)Sigma(-/+). The idea is based on considering a production mechanism as model independent as possible and implementing the final state interaction of the final meson-baryon pair based on small modifications of the unitary chiral perturbation theory amplitudes. Good fits to the data are obtained with this procedure, by means of which we can also predict the cross sections for the K- p -> (K) over barN, pi Sigma, and pi Lambda reactions for the different charge channels. Besides the two poles found for the Lambda(1405) resonance, we discuss the possible existence of an isospin 1 resonance in the vicinity of the (K) over barN threshold.
Address [Roca, L.] Univ Murcia, Dept Fis, E-30100 Murcia, Spain
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 WOS:000327315800008 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1655
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Author (up) Roca, L.; Oset, E.
Title On the hidden charm pentaquarks in Lambda(b) -> J/psi K- p decay Type Journal Article
Year 2016 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 76 Issue 11 Pages 591 - 12pp
Keywords
Abstract In a previous work we presented a theoretical analysis of the Lambda(b) -> J/psi K- p reaction based on which a recent experiment by the LHCb collaboration at CERN claimed the existence of two hidden charm pentaquarks, P-c(4380)(+) and P-c(4450)(+). In that work we focused only on the Lambda(1405) and P-c(4450)(+) signals and discussed the possible explanation of this pentaquark state within the picture of a dynamical meson-baryon molecule made up mostly from (D) over bar*Sigma(c) and (D) over bar*Sigma(c)* components. In the present work we improve upon the previous one by considering the total K- p and J/psi p data including all the relevant resonances contributing to the spectra, and discuss the possible nature of both P-c(4380)(+) and P-c(4450)(+). We also discuss several important topics, like the effect of the contact term in the reaction, the viability of reproducing the data without the P-c(4380)(+) and the possible quantum number assignment to these pentaquarks.
Address [Roca, L.] Univ Murcia, Dept Fis, E-30100 Murcia, Spain, Email: luisroca@um.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:000399930700001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3065
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Author (up) Roca, L.; Oset, E.
Title Role of a triangle singularity in the pi Delta decay of N(1700)(3/2(-)) Type Journal Article
Year 2017 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 95 Issue 6 Pages 065211 - 8pp
Keywords
Abstract We show the important role played by the pi Delta(1232) channel in the build up of the N(1700)(3/2(-)) resonance due to the nontrivial enhancement produced by a singularity of a triangular loop. The N(1700) is one of the dynamically generated resonances produced by the coupled-channel vector-baryon interaction. The pi Delta channel was neglected in previous works but we show that it has to be incorporated into the coupled-channel formalism due to an enhancement produced by a singularity in the triangular loop with., nucleon, and p as internal loop lines and pi and Delta as external ones. The enhancement is of nonresonant origin but it contributes to the dynamical generation of the N(1700) resonance due to the nonlinear dynamics involved in the coupled-channel mechanisms. We obtain an important increase of the total width of the N(1700) resonance when the pi Delta channel is included and provide predictions for the partial widths of the N(1700) decays into VB and pi Delta.
Address [Roca, L.] Univ Murcia, Dept Fis, E-30100 Murcia, Spain
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 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000404022100005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3177
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Author (up) Roca, L.; Oset, E.
Title Scalar resonances in the D+ -> K-K+K+ decay Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 103 Issue 3 Pages 034020 - 9pp
Keywords
Abstract We study theoretically the resonant structure of the double Cabibbo suppressed D+ -> K-K+K+ decay. We start from an elementary production diagram, considered subleading in previous approaches, which cannot produce a final K-K+ pair at the tree level but which we show to be able to provide the strength of the decay through final meson-meson state interaction. The different meson-meson elementary productions are related through SU(3), and the final rescattering is implemented from a suitable implementation of unitary extensions of chiral perturbation theory, which generate dynamically the scalar resonances1 f(0)(980) and a(0)(980). We obtain a good agreement with recent experimental data from the LHCb Collaboration with a minimal freedom in the fit and show the dominance of the a(0)(980) contribution close to the threshold of the K-K+ spectrum.
Address [Roca, L.] Univ Murcia, Dept Fis, E-30071 Murcia, Spain, Email: luisroca@um.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 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000621332000004 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4742
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Author (up) Roca, L.; Song, J.; Oset, E.
Title Molecular pentaquarks with hidden charm and double strangeness Type Journal Article
Year 2024 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 109 Issue 9 Pages 094005 - 8pp
Keywords
Abstract We analyze theoretically the coupled-channel meson-baryon interaction with global flavor c<overline>cssn and c<overline>csss, where mesons are pseudoscalars or vectors, and baryons have JP = 1/2+ or 3/2+. The aim is to explore whether the nonlinear dynamics inherent in the unitarization process within coupled channels can dynamically generate double- and triple-strange pentaquark-type states (Pcss and Pcsss, respectively), for which there is no experimental evidence to date. We evaluate the s-wave scattering matrix by implementing unitarity in coupled channels, using potential kernels obtained from t-channel vector meson exchange. The required PPV and VVV vertices are obtained from Lagrangians derived through appropriate extensions of the local hidden gauge symmetry approach to the charm sector, while capitalizing on the symmetry of the spin and flavor wave function to evaluate the BBV vertex. We find four different poles in the double strange sector, some of them degenerate in spin. For the triple-strange channel, we find the meson-baryon interaction insufficient to generate a bound or resonance state through the unitary coupled-channel dynamics.
Address [Roca, L.] Univ Murcia, Dept Fis, E-30100 Murcia, Spain, Email: luisroca@um.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 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:001224715500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6135
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Author (up) Sakai, S.; Roca, L.; Oset, E.
Title Charm-beauty meson bound states from B (B*)D(D*) and interaction B (B*)(D)over-bar((D)over-bar*) Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 96 Issue 5 Pages 054023 - 9pp
Keywords
Abstract We evaluate the s-wave interaction of pseudoscalar and vector mesons with both charm and beauty to investigate the possible existence of molecular BD, B* D, BD*, B* D*, B (D) over bar, B* (D) over bar, B (D) over bar*, or B* (D) over bar* meson states. The scattering amplitude is obtained implementing unitarity starting from a tree level potential accounting for the dominant vector meson exchange. The diagrams are evaluated using suitable extensions to the heavy flavor sector of the hidden gauge symmetry Lagrangians involving vector and pseudoscalar mesons, respecting heavy quark spin symmetry. We obtain bound states at energies above 7 GeV for BD (J(P) = 0(+)), B* D (1(+)), BD* (1(+)), and B* D* (0(+), 1(+,) 2(+)), all in isospin 0. For B (D) over bar (0(+)), B* (D) over bar (1(+)), B (D) over bar* (1(+)), and B* (D) over bar* (0(+), 1(+), 2(+)) we also find similar bound states in I = 0, but much less bound, which would correspond to exotic meson states with _ (b) over bar and (c) over bar quarks, and for the I = 1 we find a repulsive interaction. We also evaluate the scattering lengths in all cases, which can be tested in current investigations of lattice QCD.
Address [Sakai, S.; Oset, E.] Univ Valencia, CSIC, Inst Invest Paterna, Dept Fis Teor,Ctr Mixto, Aptdo 22085, Valencia 46071, Spain
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:000411579700002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3318
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Author (up) Song, J.; Duan, M.Y.; Roca, L.; Oset, E.
Title Pentaquark molecular states with hidden bottom and double strangeness Type Journal Article
Year 2024 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 84 Issue 10 Pages 1055 - 8pp
Keywords
Abstract We investigate the meson-baryon interaction in coupled channels with the quantum numbers of the pentaquarks Pbss and Pbsss. The interaction is derived from an extension of the local hidden gauge approach to the heavy quark sector, which has demonstrated accurate results compared to experiments involving Ωb, Ξb states, and pentaquarks Pc and Pcs. In our study, we identify several molecular states with small decay widths within the chosen set of coupled channels. The spin-parity (JP) of these states is as follows: JP=12− for pseudoscalar-baryon (12+) coupled channels, JP=32− for pseudoscalar-baryon (32+) coupled channels, JP=12− and 32− for vector-baryon (12+) coupled channels, and JP=12−, 32−, 52− for vector-baryon (32+) coupled channels. We search for the poles of these states and evaluate their couplings to the different channels.
Address [Song, Jing] Beihang Univ, Sch Phys, Beijing 102206, Peoples R China, Email: Song-Jing@buaa.edu.cn
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:001331230600005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6333
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Author (up) Wang, G.Y.; Roca, L.; Oset, E.
Title Discerning the two K-1 (1270) poles in D-0 -> pi(+) VP decay Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 100 Issue 7 Pages 074018 - 10pp
Keywords
Abstract Within the chiral unitary approach, the axial-vector resonance K-1 (1270) has been predicted to manifest a two-pole nature. The lowest pole has a mass of 1195 MeV and a width of 246 MeV and couples mostly to K*pi, and the highest pole has a mass of 1284 MeV and a width of 146 MeV and couples mostly to rho K. We analyze theoretically how this double-pole structure can show up in D-0 -> pi+VP decays by looking at the vector-pseudoscalar (VP) invariant mass distribution for different VP channels, exploiting the fact that each pole couples differently to different VP pairs. We find that the final (K) over bar*pi and rho(K) over tilde channels are sensible to the different poles of the K-1 (1270) resonance and hence are suitable reactions to analyze experimentally the double-pole nature of this resonance.
Address [Wang, G. Y.] Zhengzhou Univ, Sch Phys, Zhengzhou 450001, Henan, Peoples R China
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:000490752100003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4182
Permanent link to this record