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Author Albertus, C.; Hernandez, E.; Nieves, J.
Title Exclusive c -> s, d semileptonic decays of ground-state spin-1/2 and spin-3/2 doubly heavy cb baryons Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 85 Issue 9 Pages 094035 - 21pp
Keywords
Abstract We evaluate exclusive semileptonic decays of ground-state spin-1/2 and spin-3/2 doubly heavy cb baryons driven by a c --> s, d transition at the quark level. We check our results for the form factors against heavy quark spin symmetry constraints obtained in the limit of very large heavy quark masses and near zero recoil. Based on those constraints we make model-independent, though approximate, predictions for ratios of decay widths.
Address [Albertus, C.; 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:000304652600002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial (down) 1043
Permanent link to this record
 
 
Author Garcia-Recio, C.; Nieves, J.; Salcedo, L.L.; Tolos, L.
Title D- mesic atoms Type Journal Article
Year 2012 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 85 Issue 2 Pages 025203 - 13pp
Keywords
Abstract The anti-D meson self-energy is evaluated self-consistently, using unitarized coupled-channel theory, by computing the in-medium meson-baryon T matrix in the C = -1, S = 0 sector. The heavy pseudo-scalar and heavy vector mesons, (D) over bar and (D) over bar*, are treated on equal footing as required by heavy-quark spin symmetry. Results for energy levels and widths of (D) over bar (-) mesic atoms in C-12, Ca-40, Sn-118, and Pb-208 are presented. The spectrum contains states of atomic and of nuclear types for all nuclei. (D) over bar (0)-nucleus bound states are also obtained. We find that, after electromagnetic and nuclear cascade, these systems end up with the (D) over bar bound in the nucleus, either as a meson or as part of an exotic (D) over barN (pentaquark) loosely bound state.
Address [Garcia-Recio, C.; Salcedo, L. L.] Univ Granada, Dept Fis Atom Mol & Nucl, E-18071 Granada, 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:000300568800008 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial (down) 916
Permanent link to this record
 
 
Author Nieves, J.; Ruiz Simo, I.; Vicente Vacas, M.J.
Title The nucleon axial mass and the MiniBooNE quasielastic neutrino-nucleus scattering problem Type Journal Article
Year 2012 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 707 Issue 1 Pages 72-75
Keywords
Abstract The charged-current double differential neutrino cross section, measured by the MiniBooNE Collaboration, has been analyzed using a microscopical model that accounts for, among other nuclear effects, long range nuclear (RPA) correlations and multinucleon scattering. We find that MiniBooNE data are fully compatible with the world average of the nucleon axial mass in contrast with several previous analyses which have suggested an anomalously large value. We also discuss the reliability of the algorithm used to estimate the neutrino energy.
Address [Nieves, J.] Univ Valencia, Ctr Mixto, CSIC, Inst Invest Paterna,Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: jmnieves@ific.uv.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:000299757000010 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial (down) 903
Permanent link to this record
 
 
Author Pavon Valderrama, M.; Xie, J.J.; Nieves, J.
Title Are there three Xi (1950) states? Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 85 Issue 1 Pages 017502 - 5pp
Keywords
Abstract Different experiments on hadron spectroscopy have long suspected the existence of several cascade states in the 1900-2000 MeV region. They are usually labeled under the common name of Xi (1950). As we argue here, there are also theoretical reasons supporting the idea of several Xi (1950) resonances. In particular, we propose the existence of three Xi (1950) states: one of these states would be part of a spinparity 1/2(-) decuplet and the other two probably would belong to the 5/2(+) and 5/2(-) octets. We also identify which decay channels are more appropriate for the detection of each of the previous states.
Address [Pavon Valderrama, M.; Xie, Ju-Jun; Nieves, J.] Univ Valencia, Ctr Mixto CSIC, Inst Fis Corpuscular IFIC, 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:000298989300008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial (down) 875
Permanent link to this record
 
 
Author Flynn, J.M.; Hernandez, E.; Nieves, J.
Title Triply heavy baryons and heavy quark spin symmetry Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 85 Issue 1 Pages 014012 - 10pp
Keywords
Abstract We study the semileptonic b -> c decays of the lowest-lying triply heavy baryons made from b and c quarks in the limit m(b), m(c) >> Lambda(QCD) and close to the zero-recoil point. The separate heavy-quark spin symmetries strongly constrain the matrix elements, leading to single form factors for ccb -> ccc, bbc -> ccb, and bbb -> bbc baryon decays. We also study the effects on these systems of using a Y-shaped confinement potential, as suggested by lattice QCD results for the interaction between three static quarks.
Address [Flynn, J. M.] Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England
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:000298989300007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial (down) 874
Permanent link to this record
 
 
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 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 (down) 843
Permanent link to this record
 
 
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 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 (down) 828
Permanent link to this record
 
 
Author Nieves, J.; Pich, A.; Ruiz Arriola, E.
Title Large-N(C) properties of the rho and f(0)(600) mesons from unitary resonance chiral dynamics Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue 9 Pages 096002 - 20pp
Keywords
Abstract We construct pi pi amplitudes that fulfill exact elastic unitarity, account for one-loop chiral perturbation theory contributions and include all 1/N(C) leading terms, with the only limitation of considering just the lowest-lying nonet of exchanged resonances. Within such a scheme, the N(C) dependence of sigma and rho masses and widths is discussed. Robust conclusions are drawn in the case of the rho resonance, confirming that it is a stable meson in the limit of a large number of QCD colors, N(C). Less definitive conclusions are reached in the scalar-isoscalar sector. With the present quality of data, we cannot firmly conclude whether or not the N(C) = 3 f(0)(600) resonance completely disappears at large N(C) or if it has a subdominant component in its structure, which would become dominant for a number of quark colors sufficiently large.
Address [Nieves, J] Ctr Mixto Univ Valencia, Inst Fis Corpuscular, CSIC, IFIC, 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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000296890300012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial (down) 799
Permanent link to this record
 
 
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 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 (down) 778
Permanent link to this record
 
 
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 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 (down) 776
Permanent link to this record