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Author Roca, L.; Oset, E.
Title (up) Asymmetry observables in e(+)e(-) -> pi(+) pi(-) gamma in the phi region within a chiral unitary approach Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 81 Issue 1 Pages 014010 - 8pp
Keywords
Abstract We make a theoretical study of the charge and forward-backward pion asymmetries in the e(+)e(-) -> pi(+) pi(-) gamma process on and off the phi resonance energy. These observables are rather sensitive to the inner details of the theoretical models to describe the reaction. In addition to the standard implementation of the initial state radiation and the bremsstrahlung contribution to the final state radiation, we use the techniques of the chiral unitary approach to evaluate the contribution from the mechanisms of phi decay into pi(+) pi(-) gamma. This contribution involves the implementation of final state interaction from direct chiral loops, the exchange of vector and axial-vector resonances and the final state interaction through the consideration of the meson-meson unitarized amplitudes, which were found important in a previous work describing the phi -> pi pi gamma. We find a good reproduction of the experimental data from KLOE for the forward-backward asymmetry, both at the phi peak and away from it. We also make predictions for the angular distributions of the charge asymmetry and show that this observable is very sensitive to the chiral loops involved in phi radiative decay.
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 ISI:000274002800021 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 503
Permanent link to this record
 
 
Author Dias, J.M.; Debastiani, V.R.; Roca, L.; Sakai, S.; Oset, E.
Title (up) Binding of the BD(D)over-bar and BDD systems Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 96 Issue 9 Pages 094007 - 6pp
Keywords
Abstract We study theoretically the BD (D) over bar and BDD systems to see if they allow for possible bound or resonant states. The three-body interaction is evaluated implementing the fixed center approximation to the Faddeev equations which considers the interaction of a D or (D) over bar particle with the components of a BD cluster, previously proved to form a bound state. We find an I(J(P)) = 1/2(0(-)) bound state for the BD (D) over bar system at an energy around 8925-8985 MeV within uncertainties, which would correspond to a bottom hidden-charm meson. In contrast, for the BDD system, which would be bottom double-charm and hence manifestly exotic, we have found hints of a bound state in the energy region 8935-8985 MeV, but the results are not stable under the uncertainties of the model, and we cannot assure, nor rule out, the possibility of a BDD three-body state.
Address [Dias, J. M.; Debastiani, V. R.; Sakai, S.; Oset, E.] Univ Valencia, CSIC, Inst Invest Paterna, Dept Fis Teor, Apartado 22085, Valencia 46071, Spain, Email: jorgivan.morais@ific.uv.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:000414959300006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3359
Permanent link to this record
 
 
Author Sakai, S.; Roca, L.; Oset, E.
Title (up) 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
Permanent link to this record
 
 
Author Aceti, F.; Oset, E.; Roca, L.
Title (up) Composite nature of the Lambda (1520) resonance Type Journal Article
Year 2014 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 90 Issue 2 Pages 025208 - 8pp
Keywords
Abstract Recently, the Weinberg compositeness condition of a bound state was generalized to account for resonant states and higher partial waves. We apply this extension to the case of the Lambda (1520) resonance and quantify the weight of the meson-baryon components in contrast to other possible genuine building blocks. This resonance was theoretically obtained from a coupled channels analysis using the s-wave pi Sigma* and K Xi* and the d-wave (K) over bar N and pi Sigma channels, applying the techniques of the chiral unitary approach. We obtain the result that this resonance is essentially dynamically generated from these meson-baryon channels, leaving room for only 15% weight of other kinds of components in its wave function.
Address [Aceti, F.; Oset, E.] Univ Valencia, CSIC, Ctr Mixto, Inst Invest Paterna,Dept Fis Teor, E-46071 Valencia, 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:000341271300006 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1907
Permanent link to this record
 
 
Author Roca, L.; Oset, E.
Title (up) Description of the f(2)(1270), rho(3)(1690), f(4)(2050), rho(5)(2350), f(6)(2510) resonances as multi-rho(770) states Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 82 Issue 5 Pages 054013 - 11pp
Keywords
Abstract In a previous work regarding the interaction of two rho(770) resonances, the f(2)(1270) (J(PC) = 2(++)) resonance was obtained dynamically as a two-rho molecule with a very strong binding energy, 135 MeV per rho particle. In the present work we use the rho rho interaction in spin 2 and isospin 0 channel to show that the resonances rho(3)(1690) (3(--)), f(4)(2050) (4(++)), rho(5)(2350) (5(--)), and f(6)(2510) (6(++)) are basically molecules of increasing number of rho(770) particles. We use the fixed center approximation of the Faddeev equations to write the multibody interaction in terms of the two-body scattering amplitudes. We find the masses of the states very close to the experimental values and we get an increasing value of the binding energy per rho as the number of rho mesons is increased.
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 ISI:000281791100002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 381
Permanent link to this record
 
 
Author Wang, G.Y.; Roca, L.; Oset, E.
Title (up) 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
 
 
Author Oset, E.; Roca, L.
Title (up) Exotic molecular meson states of B(*) K(*) nature Type Journal Article
Year 2022 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 82 Issue 10 Pages 882 - 9pp
Keywords
Abstract We evaluate theoretically the interaction of the open bottom and strange systems (B) over bar (K) over bar, (B) over bar * (K) over bar, (B) over bar (K) over bar * and (B) over bar* (K) over bar* to look for possible bound states which could correspond to exotic non-quark-antiquark mesons since they would contain at least one b and one s quarks. The s-wave scattering matrix is evaluated implementing unitarity by means of the Bethe-Salpeter equation, with the potential kernels obtained from contact and vector meson exchange mechanisms. The vertices needed are supplied from Lagrangians derived from suitable extensions of the hidden gauge symmetry approach to the bottom sector. We find poles below the respective thresholds for isospin 0 interaction and evaluate the widths of the different obtained states by including the main sources of imaginary part, which are the B *-> B gamma decay in the (B) over bar * (K) over bar channels, the K *-> K pi in the channels involving a K *, plus the box diagrams with (B) over bar (K) over bar and (B) over bar * (K) over bar intermediate states for the (B) over bar * (K) over bar * channels.
Address [Oset, E.] Univ Valencia, Ctr Mixto, CSIC, Inst Invest Paterna,Dept Fis Teor, Aptdo 22085, Valencia 46071, Spain, Email: oset@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:000864656100003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5369
Permanent link to this record
 
 
Author Martinez Torres, A.; Khemchandani, K.P.; Roca, L.; Oset, E.
Title (up) Few-body systems consisting of mesons Type Journal Article
Year 2020 Publication Few-Body Systems Abbreviated Journal Few-Body Syst.
Volume 61 Issue 4 Pages 35 - 16pp
Keywords
Abstract We present a work which is meant to inspire the few-body practitioners to venture into the study of new, more exotic, systems and to hadron physicists, working mostly on two-body problems, to move in the direction of studying related few-body systems. For this purpose we devote the discussions in the introduction to show how the input two-body amplitudes can be easily obtained using techniques of the chiral unitary theory, or its extensions to the heavy quark sector. We then briefly explain how these amplitudes can be used to solve the Faddeev equations or a simpler version obtained by treating the three-body scattering as that of a particle on a fixed center. Further, we give some examples of the results obtained by studying systems involving mesons. We have also addressed the field of many meson systems, which is currently almost unexplored, but for which we envisage a bright future. Finally, we give a complete list of works dealing with unconventional few-body systems involving one or several mesons, summarizing in this way the findings on the topic, and providing a motivation for those willing to investigate such systems.
Address [Martinez Torres, A.] Univ Sao Paulo, Inst Fis, BR-05389970 Sao Paulo, Brazil, Email: amartine@if.usp.br;
Corporate Author Thesis
Publisher Springer Wien Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0177-7963 ISBN Medium
Area Expedition Conference
Notes WOS:000572646500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4546
Permanent link to this record
 
 
Author Albaladejo, M.; Oller, J.A.; Oset, E.; Rios, G.; Roca, L.
Title (up) Finite volume treatment of pi pi scattering and limits to phase shifts extraction from lattice QCD Type Journal Article
Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 071 - 22pp
Keywords Lattice QCD; Chiral Lagrangians; Phenomenological Models
Abstract We study theoretically the effects of finite volume for pi pi scattering in order to extract physical observables for infinite volume from lattice QCD. We compare three different approaches for pi pi scattering (lowest order Bethe-Salpeter approach, N/D and inverse amplitude methods) with the aim of studying the effects of the finite size of the box in the potential of the different theories, specially the left-hand cut contribution through loops in the crossed t, u-channels. We quantify the error made by neglecting these effects in usual extractions of physical observables from lattice ()CD spectrum. We conclude that for pi pi phase-shifts in the scalar-isoscalar channel up to 800 MeV this effect is negligible for box sizes bigger than 2,5m(pi)(-1) and of the order of 5% at around 1.5 – 2m(pi)(-1). For isospin 2 the finite size effects can reach up to 10% for that energy. We also quantify the error made when using the standard Luscher method to extract physical observables from lattice QCD, which is widely used in the literature but is an approximation of the one used in the present work.
Address [Albaladejo, M.; Oller, J. A.; Rios, G.; Roca, L.] Univ Murcia, Dept Fis, E-30100 Murcia, Spain, Email: albaladejo@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 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000309883600014 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1214
Permanent link to this record
 
 
Author Roca, L.; Liang, W.H.; Oset, E.
Title (up) Inconsistency of the data on the K-1(1270) -> pi K-0*(1430) decay width Type Journal Article
Year 2022 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 824 Issue Pages 136827 - 3pp
Keywords
Abstract We show, using the same Lagrangian for the K-1(1270) -> pi K-0*(1430) and K-0*(1430) -> K-1 (1270)pi decays, that the present PDG data on the partial decay width of K-1 (1270) -> pi K-0*(1430) implies a width for K-0*(1430) -> K-1 (1270)pi decay which is about one order of magnitude larger than the total K-0*(1430) width. A discussion on this inconsistency is done, stressing its relationship to the existence of two K-1(1270) states obtained with the chiral unitary theory, which are not considered in the experimental analyses of K pi pi data.
Address [Roca, L.] Univ Murcia, Dept Fis, E-30071 Murcia, Spain, Email: luisroca@um.es;
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 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000734123200006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5061
Permanent link to this record