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Author Hernandez, E.; Nieves, J.
Title Study of the strong Sigma(b) -> Lambda(b)pi and Sigma*(b) -> Lambda(b)pi in a nonrelativistic quark model Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue (up) 5 Pages 057902 - 5pp
Keywords
Abstract We present results for the strong widths corresponding to the Sigma(b) -> Lambda(b)pi and Sigma*(b) -> Lambda(b)pi decays. We apply our model from Phys. Rev. D 72, 094022 (2005), where we previously studied the corresponding transitions in the charmed sector. Our nonrelativistic constituent quark model uses wave functions that take advantage of the constraints imposed by heavy quark symmetry. The partial conservation of axial current hypothesis allows us to determine the strong vertices from an analysis of the axial current matrix elements.
Address [Hernandez, E] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, 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:000295327700002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 776
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Author Nieves, J.; Valderrama, M.P.
Title Deriving the existence of B(B)over-bar* bound states from the X(3872) and heavy quark symmetry Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue (up) 5 Pages 056015 - 21pp
Keywords
Abstract We discuss the possibility and the description of bound states between B and (B) over bar* mesons. We argue that the existence of such a bound state can be deduced from (i) the weakly bound X(3872) state, (ii) certain assumptions about the short-range dynamics of the D (D) over bar* system and (iii) heavy quark symmetry. From these assumptions the binding energy of the possible B (B) over bar* bound states is determined, first in a theory containing only contact interactions which serves as a straightforward illustration of the method, and then the effects of including the one-pion exchange potential are discussed. In this latter case three isoscalar states are predicted: a positive and negative C-parity (3)S(1) – (3)D(1) state with a binding energy of 20 MeV and 6 MeV below threshold, respectively, and a positive C-parity (3)P(0) shallow state located almost at the B (B) over bar* threshold. However, large uncertainties are generated as a consequence of the 1/m(Q) corrections from heavy quark symmetry. Finally, the newly discovered isovector Z(b)(10610) state can be easily accommodated within the present framework by a minor modification of the short-range dynamics.
Address [Nieves, J] Univ Valencia, Dept Fis Teor, Inst Invest Paterna, Ctr Mixto,CSIC, E-46071 Valencia, Spain, Email: m.pavon.valderrama@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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000295267700006 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 778
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Author Albertus, C.; Hernandez, E.; Nieves, J.
Title Exclusive c -> s, d semileptonic decays of ground-state spin-1/2 doubly charmed baryons Type Journal Article
Year 2011 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 704 Issue (up) 5 Pages 499-509
Keywords
Abstract We evaluate exclusive semileptonic decays of ground-state spin-1/2 doubly heavy charmed baryons driven by a c -> s, d transition at the quark level. Our results for the form factors are consistent with heavy quark spin symmetry constraints which are valid in the limit of an infinitely massive charm quark and near zero recoil. Only a few exclusive semileptonic decay channels have been theoretically analyzed before. For those cases we find that our results are in a reasonable agreement with previous calculations.
Address [Albertus, C.; Hernandez, E.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: gajatee@usal.es
Corporate Author Thesis
Publisher Elsevier Science Bv 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:000296549200017 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 828
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Author Gamermann, D.; Garcia-Recio, C.; Nieves, J.; Salcedo, L.L.
Title Odd-parity light baryon resonances Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue (up) 5 Pages 056017 - 30pp
Keywords
Abstract We use a consistent SU(6) extension of the meson-baryon chiral Lagrangian within a coupled channel unitary approach in order to calculate the T matrix for meson-baryon scattering in the s wave. The building blocks of the scheme are the pi and N octets, the rho nonet and the UDELTA; decuplet. We identify poles in this unitary T matrix and interpret them as resonances. We study here the nonexotic sectors with strangeness S = 0, -1, -2, -3 and spin J = 1/2, 3/2 and 5/2. Many of the poles generated can be asociated with known N, UDELTA;, sigma, Lambda, Xi and Omega resonances with negative parity. We show that most of the low-lying three and four star odd-parity baryon resonances with spin 1/2 and 3/2 can be related to multiplets of the spin-flavor symmetry group SU(6). This study allows us to predict the spin-parity of the Xi (1620), Xi (1690), Xi (1950), Xi (2250), Omega (2250) and Omega (2380) resonances, which have not been determined experimentally yet.
Address [Gamermann, D.] Univ Catolica Valencia San Vicente Martir, Catedra Energesis Tecnol Interdisciplinar, E-46003 Valencia, Spain, Email: daga1@upvnet.upv.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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000294404700008 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 843
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Author Nieves, J.; Pavon Valderrama, M.
Title Heavy quark spin symmetry partners of the X(3872) Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 86 Issue (up) 5 Pages 056004 - 18pp
Keywords
Abstract We explore the consequences of heavy quark spin symmetry for the charmed meson-antimeson system in a contact-range (or pionless) effective field theory. As a trivial consequence, we theorize the existence of a heavy quark spin symmetry partner of the X(3872), with J(PC) = 2(++), which we call X(4012) in reference to its predicted mass. If we additionally assume that the X(3915) is a 0(++) heavy spin symmetry partner of the X(3872), we end up predicting a total of six D-(*())(D) over bar (()*()) molecular states. We also discuss the error induced by higher order effects such as finite heavy quark mass corrections, pion exchanges and coupled channels, allowing us to estimate the expected theoretical uncertainties in the position of these new states.
Address [Nieves, J.; Pavon Valderrama, M.] Univ Valencia, Inst Fis Corpuscular IFIC, Ctr Mixto CSIC, Inst Invest Paterna, E-46071 Valencia, Spain, Email: m.pavon.valderrama@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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000308869400013 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1162
Permanent link to this record