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Author (up) Abreu, L.M.; Song, J.; Brandao, P.C.S.; Oset, E.
Title A note on the tensor and vector exchange contributions to K (K)over-bar → K (K)over-bar, D(D)over-bar → D(D)over-bar and π+π- → π+π- reactions Type Journal Article
Year 2024 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 60 Issue 3 Pages 76 - 10pp
Keywords
Abstract In this note we study the tensor and vector exchange contributions to the elastic reactions involving the pseudoscalars mesons pi(+) pi(-), K+ K- and D+D-. In the case of the tensor-exchange contributions we assume that an intermediate tensor f(2)(1270) is dynamically generated from the interaction of two virtual rho mesons, with the use of a pole approximation. The calculation of the two-loop amplitude is facilitated since the triangle loops can be factorized and computed separately. The results show very small contributions coming from the tensor-exchange mechanisms when compared with those from the vector-exchange processes. We compare our results for pi pi and K (K) over bar scattering with those obtained in other works where the f2(1270) is considered as an ordinary q (q) over bar meson. Our picture provides a smaller contribution but of similar order of magnitude for pion scattering and stabilizes the results in the case of K (K) over bar, allowing us to make estimates for D (D) over bar scattering.
Address [Abreu, Luciano M.; Brandao, Pedro C. S.] Univ Fed Bahia, Inst Fis, Campus Ondina, BR-40170115 Salvador, BA, Brazil, Email: luciano.abreu@ufba.br;
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 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:001195442000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6036
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Author (up) Brandao, P.C.S.; Song, J.; Abreu, L.M.; Oset, E.
Title B+ decay to K+ ηη with (ηη) from the D bar-D(3720) bound state Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 108 Issue 5 Pages 054004 - 6pp
Keywords
Abstract We search for a B decay mode where one can find a peak for a DD bound state predicted in effective theories and in lattice QCD calculations, which has also been claimed from some reactions that show an accumulated strength in D D over bar production at threshold. We find a good candidate in the B+-> K+eta eta reaction, by looking at the eta eta mass distribution. The reaction proceeds via a first step in which one has the B+-> D*+ D-0 reaction followed by D*(+) (s) decay to (DK+)-K-0 and a posterior fusion of D-0 over bar D-0 to eta eta, implemented through a triangle diagram that allows the D-0 over bar D-0 to be virtual and to produce the bound state. The choice of eta eta to see the peak is based on results of calculations that find the eta eta among the light pseudoscalar channels with stronger coupling to the D D over bar bound state. We find a neat peak around the predicted mass of that state in the eta eta mass distribution, with an integrated branching ratio for B+-> K+ (D D, bound); (D D, bound) -> eta eta of the order of 1.5 x 10(-4), a large number for hadronic B decays, which should motivate its experimental search.
Address [Brandao, Pedro C. S.; Abreu, Luciano M.; Oset, E.] Univ Fed Bahia, Inst Fis, Campus Ondina, BR-40170115 Salvador, BA, Brazil, Email: pedro.brandao@ufba.br;
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:001085561600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5765
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Author (up) Dai, L.R.; Song, J.; Oset, E.
Title Evolution of genuine states to molecular ones: The Tcc(3875) case Type Journal Article
Year 2023 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 846 Issue Pages 138200 - 6pp
Keywords
Abstract We address the issue of the compositeness of hadronic states and demonstrate that starting with a genuine state of nonmolecular nature, but which couples to some meson-meson component to be observable in that channel, if that state is blamed for a bound state appearing below the meson-meson threshold it gets dressed with a meson cloud and it becomes pure molecular in the limit case of zero binding. We discuss the issue of the scales, and see that if the genuine state has a mass very close to threshold, the theorem holds, but the molecular probability goes to unity in a very narrow range of energies close to threshold. The conclusion is that the value of the binding does not determine the compositeness of a state. However, in such extreme cases we see that the scattering length gets progressively smaller and the effective range grows indefinitely. In other words, the binding energy does not determine the compositeness of a state, but the additional information of the scattering length and effective range can provide an answer. We also show that the consideration of a direct attractive interaction between the mesons in addition to having a genuine component, increases the compositeness of the state. Explicit calculations are done for the Tcc(3875) state, but are easily generalized to any hadronic system.
Address [Dai, L. R.] Huzhou Univ, Sch Sci, Huzhou 313000, Zhejiang, Peoples R China, Email: dailianrong@zjhu.edu.cn;
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:001088653400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5760
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Author (up) Song, J.; Dai, L.R.; Oset, E.
Title Evolution of compact states to molecular ones with coupled channels: The case of the X(3872) Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 108 Issue 11 Pages 114017 - 11pp
Keywords
Abstract We study the molecular probability of the X(3872) in the D0 over bar D*0 and D+D*- channels in several scenarios. One of them assumes that the state is purely due to a genuine nonmolecular component. However, it gets unavoidably dressed by the meson components to the point that in the limit of zero binding of the D0 over bar D*0 component becomes purely molecular. Yet, the small but finite binding allows for a nonmolecular state when the bare mass of the genuine state approaches the D0 over bar D*0 threshold, but, in this case the system develops a small scattering length and a huge effective range for this channel in flagrant disagreement with present values of these magnitudes. Next we discuss the possibility to have hybrid states stemming from the combined effect of a genuine state and a reasonable direct interaction between the meson components, where we find cases in which the scattering length and effective range are still compatible with data, but even then the molecular probability is as big as 95%. Finally, we perform the calculations when the binding stems purely from the direct interaction between the meson-meson components. In summary we conclude, that while present data definitely rule out the possibility of a dominant nonmolecular component, the precise value of the molecular probability requires a more precise determination of the scattering length and effective range of the D0 over bar D*0 channel, as well as the measurement of these magnitudes for the D+D*- channel which have not been determined experimentally so far.
Address [Song, Jing] Beihang Univ, Sch Phys, Beijing 102206, Peoples R China, Email: Song-Jing@buaa.edu.cn;
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:001134845500013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5963
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Author (up) Song, J.; Dai, L.R.; Oset, E.
Title How much is the compositeness of a bound state constrained by a and r(0)? The role of the interaction range Type Journal Article
Year 2022 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 58 Issue 7 Pages 133 - 10pp
Keywords
Abstract We present an approach that allows one to obtain information on the compositeness of molecular states from combined information of the scattering length of the hadronic components, the effective range, and the binding energy. We consider explicitly the range of the interaction in the formalism and show it to be extremely important to improve on the formula of Weinberg obtained in the limit of very small binding and zero range interaction. The method allows obtaining good information also in cases where the binding is not small. We explicitly apply it to the case of the deuteron and the D-s0* (2317) and D-s1* (2460) states and determine simultaneously the value of the compositeness within a certain range, as well as get qualitative information on the range of the interaction.
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 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000829615100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5308
Permanent link to this record