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Author Miyahara, K.; Hyodo, T.; Oka, M.; Nieves, J.; Oset, E.
Title Theoretical study of the Xi(1620) and Xi(1690) resonances in Xi(c)-> pi(+) MB decays Type Journal Article
Year 2017 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume (down) 95 Issue 3 Pages 035212 - 12pp
Keywords
Abstract Nonleptonic weak decays of Xi(c) into pi(+) and a meson (M)-baryon (B) final state, MB, are analyzed from the viewpoint of probing S = -2 baryon resonances, i.e., Xi(1620) and Xi(1690), of which spin-parity and other properties are not well known. We argue that the weak decay of Xi(c) is dominated by a single quark-line diagram, preferred by the Cabibbo-Kobayashi-Maskawa coefficient, color recombination factor, the diquark correlation, and the kinematical condition. The decay process has an advantage of being free from meson resonances in the p+ M invariantmass distribution. The invariant mass distribution of the meson-baryon final state is calculated with three different chiral unitary approaches, assuming that the Xi(1620) and Xi(1690) resonances have J(P) = 1/2(-). It is found that a clear peak for the Xi(1690) is seen in the pi Xi and K Lambda spectra. We also suggest that the ratios of the pi Xi, K Lambda, and K Sigma final states are useful to distinguish whether the peak is originated from the Xi(1690) resonance or it is a K Sigma threshold effect.
Address [Miyahara, Kenta] Kyoto Univ, Grad Sch Sci, Dept Phys, Kyoto 6068502, Japan, Email: miyahara.kenta.62r@st.kyoto-u.ac.jp
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:000399144100008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3044
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Author 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 (down) 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 Geng, L.S.; Oset, E.
Title Novel nonperturbative approach for radiative (B)over-bar(0)((B)over-bar(s)(0)) -> J/psi gamma decays Type Journal Article
Year 2016 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 94 Issue 1 Pages 014018 - 11pp
Keywords
Abstract Radiative (B) over bar (0)((B) over bar (0)(s)) -> J/psi gamma decays provide an interesting case to test our understanding of ( non) perturbative QCD and eventually to probe physics beyond the standard model. Recently, the LHCb Collaboration reported an upper bound, updating the results of the BABAR Collaboration. Previous theoretical predictions based on QCD factorization or perturbative QCD have shown large variations due to different treatment of nonfactorizable contributions and meson-photon transitions. In this paper, we report on a novel approach to estimate the decay rates, which is based on a recently proposed model for B decays and the vector meson dominance hypothesis, widely tested in the relevant energy regions. The predicted branching ratios are Br[(B) over bar (0) -> J/psi gamma] = (3.50 +/- 0.34(-0.63)(+1.12)) x 10(-8) and Br[(B) over bar (0)(s) -> J/psi gamma] = (7.20 +/- 0.68(-1.30)(+2.31)) x 10(-7). The first uncertainty is systematic and the second is statistical, originating from the experimental (B) over bar (0)(s) -> J/psi gamma branching ratio.
Address [Geng, Li-Sheng] Beihang Univ, Sch Phys & Nucl Energy Engn, Beijing 100191, Peoples R China, Email: lisheng.geng@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:000380111000004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2767
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Author Dias, J.M.; Navarra, F.S.; Nielsen, M.; Oset, E.
Title f(0)(980) production in D-s(+)-> pi(+) pi(+) pi(-) and D-s(+) -> pi(+) K+ K- decays Type Journal Article
Year 2016 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 94 Issue 9 Pages 096002 - 8pp
Keywords
Abstract We study the D-s(+)-> pi(+) pi(+) pi(-) and D-s(+) -> pi(+) K+ K- decays adopting a mechanism in which the D-s(+) meson decays weakly into a pi+ and a q (q) over bar component, which hadronizes into two pseudoscalar mesons. The final state interaction between these two pseudoscalar mesons is taken into account by using the chiral unitary approach in coupled channels, which gives rise to the f(0)(980) resonance. Hence, we obtain the invariant mass distributions of the pairs pi(+) pi(-) and K+ K- after the decay of that resonance and compare our theoretical amplitudes with those available from the experimental data. Our results are in a fair agreement with the shape of these data, within large experimental uncertainty, and a f(0)(980) signal is seen in both the pi(+) pi(-) and K+ K- distributions. Predictions for the relative size of pi(+) pi(-) and K+ K- distributions are made.
Address [Dias, J. M.; Navarra, F. S.; Nielsen, M.] Univ Sao Paulo, Inst Fis, CP 66318, BR-05389970 Sao Paulo, SP, Brazil, Email: jdias@if.usp.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:000386896900006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2843
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Author Bayar, M.; Aceti, F.; Guo, F.K.; Oset, E.
Title Discussion on triangle singularities in the Lambda(b) -> J/psi K(-)p reaction Type Journal Article
Year 2016 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume (down) 94 Issue 7 Pages 074039 - 10pp
Keywords
Abstract We have analyzed the singularities of a triangle loop integral in detail and derived a formula for an easy evaluation of the triangle singularity on the physical boundary. It is applied to the Lambda(b) -> J/psi K(-)p process via Lambda*-charmonium-proton intermediate states. Although the evaluation of absolute rates is not possible, we identify the chi(c1) and the psi(2S)as the relatively most relevant states among all possible charmonia up to the psi(2S). The Lambda(1890)chi(c1)p loop is very special, as its normal threshold and triangle singularities merge at about 4.45 GeV, generating a narrow and prominent peak in the amplitude in the case that the chi(c1)p is in an S wave. We also see that loops with the same charmonium and other Lambda* hyperons produce less dramatic peaks from the threshold singularity alone. For the case of chi(c1)p -> J/psi p and quantum numbers 3/2(-) or 5/2(+), one needs P and D waves, respectively, in the chi(c1)p, which drastically reduce the strength of the contribution and smooth the threshold peak. In this case, we conclude that the singularities cannot account for the observed narrow peak. In the case of 1/2(+), 3/2(-) quantum numbers, where chi(c1)p -> J/psi p can proceed in an S wave, the Lambda(1890)chi(c1)p triangle diagram could play an important role, though neither can assert their strength without further input from experiments and lattice QCD calculations.
Address [Bayar, Melahat] Kocaeli Univ, Dept Phys, TR-41380 Izmit, Turkey
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:000387256100003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2854
Permanent link to this record