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Author Liang, W.H.; Chen, H.X.; Oset, E.; Wang, E.
Title Triangle singularity in the J/psi -> K+K- f(0)(980)(a(0)(980)) decays Type Journal Article
Year 2019 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 79 Issue 5 Pages 411 - 11pp
Keywords
Abstract (down) We study the J/psi -> K+K- f(0)(980)(a(0)(980)) reaction and find that the mechanism to produce this decay develops a triangle singularity around M-inv(K- f(0)/K- a(0)) approximate to 1515 MeV. The differential width d Gamma/dM(inv)(K- f(0)/K- a(0)) shows a rapid growth around the invariant mass being 1515 MeV as a consequence of the triangle singularity of this mechanism, which is directly tied to the nature of the f(0)(980) and a(0)(980) as dynamically generated resonances from the interaction of pseudoscalar mesons. The branching ratios obtained for the J/psi -> K+K- f(0)(980)(a(0)(980)) decays are of the order of 10(-5), accessible in present facilities, and we argue that their observation should provide relevant information concerning the nature of the low-lying scalar mesons.
Address [Liang, Wei-Hong; Oset, Eulogio] Guangxi Normal Univ, Dept Phys, Guilin 541004, Peoples R China, Email: hxchen@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:000468113500003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4022
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Author Nieves, J.; Pavao, R.; Sakai, S.
Title Lambda(b) decays into Lambda cl(nu)over-barl and Lambda c*pi(-) [ Lambda(c)* = Lambda(c)( 2595) and Lambda(c)(2625)] and heavy quark spin symmetry Type Journal Article
Year 2019 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 79 Issue 5 Pages 417 - 20pp
Keywords
Abstract (down) We study the implications for bc=c(2595) and c(2625)] decays that can be deduced from heavy quark spin symmetry (HQSS). Identifying the odd parity c(2595) and c(2625) resonances as HQSS partners, with total angular momentum-parity jqP=1- for the light degrees of freedom, we find that the ratios (bc(2595)-)/(bc(2625)-) and (bc(2595)) agree, within errors, with the experimental values given in the Review of Particle Physics. We discuss how future, and more precise, measurements of the above branching fractions could be used to shed light into the inner HQSS structure of the narrow c(2595) odd-parity resonance. Namely, we show that such studies would constrain the existence of a sizable jqP</mml:msubsup>=0- component in its wave-function, and/or of a two-pole pattern, in analogy to the case of the similar (1405) resonance in the strange sector, as suggested by most of the approaches that describe the c(2595) as a hadron molecule. We also investigate the lepton flavor universality ratios R[c]=B( may be affected by a new source of potentially large systematic errors if there are two) poles.
Address [Nieves, J.; Pavao, R.] Ctr Mixto CSIC UV, Inst Fis Corpuscular, Inst Invest Paterna, Aptdo 22085, Valencia 46071, Spain, Email: shsakai@itp.ac.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:000468374700002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4021
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Author Oldengott, I.M.; Barenboim, G.; Kahlen, S.; Salvado, J.; Schwarz, D.J.
Title How to relax the cosmological neutrino mass bound Type Journal Article
Year 2019 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 049 - 18pp
Keywords neutrino masses from cosmology; cosmological neutrinos; cosmological parameters from CMBR; cosmological parameters from LSS
Abstract (down) We study the impact of non-standard momentum distributions of cosmic neutrinos on the anisotropy spectrum of the cosmic microwave background and the matter power spectrum of the large scale structure. We show that the neutrino distribution has almost no unique observable imprint, as it is almost entirely degenerate with the effective number of neutrino flavours, N-eff, and the neutrino mass, m(nu). Performing a Markov chain Monte Carlo analysis with current cosmological data, we demonstrate that the neutrino mass bound heavily depends on the assumed momentum distribution of relic neutrinos. The message of this work is simple and has to our knowledge not been pointed out clearly before: cosmology allows that neutrinos have larger masses if their average momentum is larger than that of a perfectly thermal distribution. Here we provide an example in which the mass limits are relaxed by a factor of two.
Address [Oldengott, Isabel M.; Barenboim, Gabriela] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain, Email: isabel.oldengott@uv.es;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000466578400003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4001
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Author Dai, L.R.; Wang, G.Y.; Chen, X.; Wang, E.; Oset, E.; Li, D.M.
Title The B+ -> J/phi omega K+ reaction and D*(D)over-bar* molecular states Type Journal Article
Year 2019 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 55 Issue 3 Pages 36 - 7pp
Keywords
Abstract (down) We study the B+J/K+ reaction, and show that it is driven by the presence of two resonances, the X(3940) and X(3930), that are of molecular nature and couple most strongly to D*D*, but also to J/. Because of that, in the J/ mass distribution we find a peak related to the excitation of the resonances and a cusp with large strength at the D*D* threshold.
Address [Dai, L. R.; Chen, X.] Liaoning Normal Univ, Dept Phys, Dalian 116029, Peoples R China, Email: dailr@lnnu.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:000461209300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3942
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Author Molina, R.; Geng, L.S.; Oset, E.
Title Comments on the dispersion relation method to vector-vector interaction Type Journal Article
Year 2019 Publication Progress of Theoretical and Experimental Physics Abbreviated Journal Prog. Theor. Exp. Phys.
Volume Issue 10 Pages 103B05 - 16pp
Keywords
Abstract (down) We study in detail the method proposed recently to study the vector-vector interaction using the N/D method and dispersion relations, which concludes that, while, for J = 0, one finds bound states, in the case of J = 2, where the interaction is also attractive and much stronger, no bound state is found. In that work, approximations are done for N and D and a subtracted dispersion relation for D is used, with subtractions made up to a polynomial of second degree in s – s(th), matching the expression to 1 – VG at threshold. We study this in detail for the rho rho interaction and to see the convergence of the method we make an extra subtraction matching 1 – VG at threshold up to (s – s(th))(3). We show that the method cannot be used to extrapolate the results down to 1270 MeV where the f(2)(1270) resonance appears, due to the artificial singularity stemming from the “on-shell” factorization of the rho exchange potential. In addition, we explore the same method but folding this interaction with the mass distribution of the rho, and we show that the singularity disappears and the method allows one to extrapolate to low energies, where both the (s – s(th))(2) and (s – s(th))(3) expansions lead to a zero of Re D(s), at about the same energy where a realistic approach produces a bound state. Even then, the method generates a large Im D(s) that we discuss is unphysical.
Address [Molina, R.] Univ Complutense Madrid, Fac Fis, Dept Fis Teor 2, Plaza Ciencias 1, E-28040 Madrid, Spain, Email: ramolinape@gmail.com
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:000493500800006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4190
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