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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 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 (up) 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000295267700006 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 778
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 (up) 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000296890300012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 799
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 (up) 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000294404700008 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 843
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 (up) 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000298989300007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 874
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 (up) 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000298989300008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 875
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 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 (up) 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000304652600002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1043
Permanent link to this record
 
 
Author Nieves, J.; Sanchez, F.; Ruiz Simo, I.; Vicente Vacas, M.J.
Title Neutrino energy reconstruction and the shape of the charged current quasielastic-like total cross section Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 85 Issue 11 Pages 113008 - 9pp
Keywords
Abstract We show that because of the multinucleon mechanism effects, the algorithm used to reconstruct the neutrino energy is not adequate when dealing with quasielastic-like events, and a distortion of the total flux-unfolded cross-section shape is produced. This amounts to a redistribution of strength from high to low energies, which gives rise to a sizable excess (deficit) of low (high) energy neutrinos. This distortion of the shape leads to a good description of the MiniBooNE unfolded charged current quasielastic-like cross sections published by A. A. Aguilar-Arevalo et al. [(MiniBooNE Collaboration), Phys. Rev. D 81, 092005 (2010)]. However, these changes in the shape are artifacts of the unfolding process that ignores multinucleon mechanisms.
Address [Nieves, J.] Ctr Mixto Univ Valencia CSIC, Inst Fis Corpuscular IFIC, Inst Invest Paterna, E-46071 Valencia, 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 (up) 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000305560500002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1077
Permanent link to this record
 
 
Author Romanets, O.; Tolos, L.; Garcia-Recio, C.; Nieves, J.; Salcedo, L.L.; Timmermans, R.G.E.
Title Charmed and strange baryon resonances with heavy-quark spin symmetry Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 85 Issue 11 Pages 114032 - 30pp
Keywords
Abstract We study charmed and strange baryon resonances that are generated dynamically by a unitary baryon-meson coupled-channel model which incorporates heavy-quark spin symmetry. This is accomplished by extending the SU(3) Weinberg-Tomozawa chiral Lagrangian to SU(8) spin-flavor symmetry plus a suitable symmetry breaking. The model produces resonances with negative parity from s-wave interaction of pseudoscalar and vector mesons with 1/2(+) and 3/2(+) baryons. Resonances in all the isospin, spin, and strange sectors with one, two, and three charm units are studied. Our results are compared with experimental data from several facilities, such as the CLEO, Belle or BABAR collaborations, as well as with other theoretical models. Some of our dynamically-generated states can be readily assigned to resonances found experimentally, while others do not have a straightforward identification and require the compilation of more data and also a refinement of the model. In particular, we identify the Xi(c)(2790) and Xi(c)(2815) resonances as possible candidates for a heavy-quark spin symmetry doublet.
Address [Romanets, O.; Tolos, L.; Timmermans, R. G. E.] Univ Groningen, KVI, NL-9747 AA Groningen, Netherlands
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 (up) 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000305560500004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1078
Permanent link to this record
 
 
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 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 (up) 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
 
 
Author Garcia-Recio, C.; Nieves, J.; Romanets, O.; Salcedo, L.L.; Tolos, L.
Title Odd parity bottom-flavored baryon resonances Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 87 Issue 3 Pages 034032 - 9pp
Keywords
Abstract The LHCb Collaboration has recently observed two narrow baryon resonances with beauty. Their masses and decay modes look consistent with the quark model orbitally excited states Lambda(b)(5912) and Lambda(b)*(5920), with quantum numbers J(P) = 1/2(-) and 3/2(-), respectively. We predict the existence of these states within a unitarized meson-baryon coupled-channel dynamical model, which implements heavy-quark spin symmetry. Masses, quantum numbers and couplings of these resonances to the different meson-baryon channels are obtained. We find that the resonances Lambda(0)(b)(5912) and Lambda(0)(b)(5920) are heavy-quark spin symmetry partners, which naturally explains their approximate mass degeneracy. Corresponding bottom-strange baryon resonances are predicted at Xi(b)(6035.4) (J(P) = 1/2(-)) and Xi(b)(6043.3) (J(P) = 3/2(-)). The two Lambda(b) and two Xi(b) resonances complete a multiplet of the combined symmetry SU(3)-flavor times heavy-quark spin.
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 (up) 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000315149000004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1332
Permanent link to this record