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Author Nieves, J.; Pavao, R.; Sakai, S. url  doi
openurl 
  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 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 (up) 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 Nieves, J.; Pavao, R.; Tolos, L. url  doi
openurl 
  Title Xi(c) and Xi(b) excited states within a SU(6)(lsf) x HQSS model Type Journal Article
  Year 2020 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C  
  Volume 80 Issue 1 Pages 22 - 12pp  
  Keywords  
  Abstract We study odd parity J = 1/2 and J = 3/2 Xi(c) resonances using a unitarized coupled-channel framework based on a SU(6)(lsf) xHQSS-extended Weinberg-Tomozawa baryon-meson interaction, while paying a special attention to the renormalization procedure. We predict a large molecular Lambda(c)(K) over bar component for the Xi(c) (2790) with a dominant 0(-) light-degree-of-freedom spin configuration. We discuss the differences between the 3/2(-) Lambda(c)(2625) and Xi(c)(2815) states, and conclude that they cannot be SU(3) siblings, whereas we predict the existence of other Xi(c)-states, one of them related to the two-pole structure of the Lambda(c)(2595). It is of particular interest a pair of J = 1/2 and J = 3/2 poles, which form a HQSS doublet and that we tentatively assign to the Xi(c)(2930) and Xi(c)(2970), respectively. Within this picture, the Xi(c)(2930) would be part of a SU(3) sextet, containing either the Omega(c)(3090) or the Omega(c)(3119), and that would be completed by the Sigma(c)(2800). Moreover, we identify a J = 1/2 sextet with the Xi(b)(6227) state and the recently discovered Sigma(b)(6097). Assuming the equal spacing rule and to complete this multiplet, we predict the existence of a J = 1/2 Omega(b) odd parity state, with a mass of 6360 MeV and that should be seen in the Xi(b) (K) over bar channel.  
  Address [Nieves, J.; Pavao, R.] UV, CSIC, Inst Invest Paterna, Inst Fis Corpuscular,Ctr Mixto, Aptdo 22085, Valencia 46071, Spain, Email: tolos@ice.csic.es  
  Corporate Author Thesis  
  Publisher (up) 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:000514590400004 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4295  
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Author Bourguille, B.; Nieves, J.; Sanchez, F. url  doi
openurl 
  Title Inclusive and exclusive neutrino-nucleus cross sections and the reconstruction of the interaction kinematics Type Journal Article
  Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 04 Issue 4 Pages 004 - 42pp  
  Keywords Phenomenological Models  
  Abstract We present a full kinematic analysis of neutrino-nucleus charged current quasielastic interactions based on the Local Fermi Gas model and the Random Phase Approximation. The model was implemented in the NEUT Monte Carlo framework, which allows us to investigate potentially measurable observables, including hadron distributions. We compare the predictions simultaneously to the most recent T2K and MINERvA charged current (CC) inclusive, CC0 pi and transverse kinematic-imbalance variable results. We pursuit a microscopic interpretation of the relevant reaction mechanisms, with the aim to achieving in neutrino oscillation experiments a correct reconstruction of the incoming neutrino kinematics, free of conceptual biasses. Such study is of the utmost importance for the ambitious experimental program which is underway to precisely determine neutrino properties, test the three-generation paradigm, establish the order of mass eigenstates and investigate leptonic CP violation.  
  Address [Bourguille, B.] Univ Autonoma Barcelona, Inst Fis Altes Energies IFAE, Barcelona Inst Sci & Technol, Edifici Cn, Bellaterra, Barcelona, Spain, Email: bruno.bourguille@free.fr;  
  Corporate Author Thesis  
  Publisher (up) Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000636427400001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4774  
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Author Penalva, N.; Hernandez, E.; Nieves, J. url  doi
openurl 
  Title New physics and the tau polarization vector in b -> c tau barnutau decays Type Journal Article
  Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 06 Issue 6 Pages 118 - 37pp  
  Keywords Beyond Standard Model; CP violation  
  Abstract For a general H-b -> Hc tau nu <overbar></mml:mover>tau decay we analyze the role of the tau polarization vector P μin the context of lepton flavor universality violation studies. We use a general phenomenological approach that includes, in addition to the Standard Model (SM) contribution, vector, axial, scalar, pseudoscalar and tensor new physics (NP) terms which strength is governed by, complex in general, Wilson coefficients. We show that both in the laboratory frame, where the initial hadron is at rest, and in the center of mass of the two final leptons, a P -></mml:mover> component perpendicular to the plane defined by the three-momenta of the final hadron and the tau lepton is only possible for complex Wilson coefficients, being a clear signal for physics beyond the SM as well as time reversal (or CP-symmetry) violation. We make specific evaluations of the different polarization vector components for the Lambda (b) -> Lambda (c), <mml:mover accent=“true”>B<mml:mo stretchy=“true”><overbar></mml:mover>c -> eta (c), J/psi and <mml:mover accent=“true”>B<mml:mo stretchy=“true”><overbar></mml:mover> -> D-(*) semileptonic decays, and describe NP effects in the complete two-dimensional space associated with the independent kinematic variables on which the polarization vector depends. We find that the detailed study of P μhas great potential to discriminate between different NP scenarios for 0(-) -> 0(-) decays, but also for Lambda (b) -> Lambda (c) transitions. For this latter reaction, we pay special attention to corrections to the SM predictions derived from complex Wilson coefficients contributions.  
  Address [Penalva, Neus; Nieves, Juan] Ctr Mixto CSIC UV, Inst Invest Paterna, Inst Fis Corpuscular, Apartado 22085, Valencia 46071, Spain, Email: Neus.Penalva@ific.uv.es;  
  Corporate Author Thesis  
  Publisher (up) Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000664505100002 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 4882  
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Author Penalva, N.; Hernandez, E.; Nieves, J. url  doi
openurl 
  Title The role of right-handed neutrinos in b -> c tau (pi nu(tau), rho nu(tau), mu(nu)over-bar(mu)nu(tau))(nu)over-bar(tau) from visible final-state kinematics Type Journal Article
  Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 10 Issue 10 Pages 122 - 45pp  
  Keywords Beyond Standard Model; CP violation  
  Abstract In the context of lepton flavor universality violation (LFUV) studies, we fully derive a general tensor formalism to investigate the role that left- and right-handed neutrino new-physics (NP) terms may have in b -> c tau(nu) over bar (tau) transitions. We present, for several extensions of the Standard Model (SM), numerical results for the Lambda(b) -> Lambda(c)tau(nu) over bar (tau) semileptonic decay, which is expected to be measured with precision at the LHCb. This reaction can be a new source of experimental information that can help to confirm, or maybe rule out, LFUV presently seen in (B) over bar meson decays. The present study analyzes observables that can help in distinguishing between different NP scenarios that otherwise provide very similar results for the branching ratios, which are our currently best hints for LFUV. Since the tau lepton is very short-lived, we consider three subsequent tau-decay modes, two hadronic pi nu(tau) and rho nu(tau) and one leptonic mu(nu) over bar (mu)nu(tau), which have been previously studied for (B) over bar -> D(*) decays. Within the tensor formalism that we have developed in previous works, we re-obtain the expressions for the differential decay width written in terms of visible (experimentally accessible) variables of the massive particle created in the tau decay. There are seven different tau angular and spin asymmetries that are defined in this way and that can be extracted from experiment. Those asymmetries provide observables that can help in constraining possible SM extensions.  
  Address [Penalva, Neus; Nieves, Juan] Ctr Mixto CSIC UV, Inst Fis Corpuscular, Inst Invest Paterna, C Catedrat Jose Beltran 2, E-46980 Valencia, Spain, Email: neus.penalva@ific.uv.es;  
  Corporate Author Thesis  
  Publisher (up) Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000708483600004 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 5005  
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Author Penalva, N.; Hernandez, E.; Nieves, J. url  doi
openurl 
  Title Visible energy and angular distributions of the charged particle from the tau-decay in b -> C tau (mu(nu)over-bar(mu)nu(tau), pi nu(tau), rho nu(tau))(nu)over-bar(tau) reactions Type Journal Article
  Year 2022 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 04 Issue 4 Pages 026 - 25pp  
  Keywords Bottom Quarks; Semi-Leptonic Decays; Flavour Symmetries; Left-Right Models  
  Abstract We study the d(2)Gamma(d)/(d omega d cos theta(d) ), d Gamma(d)/d cos theta(d) and d Gamma(d)/dE(d) distributions, which are defined in terms of the visible energy and polar angle of the charged particle from the tau-decay in b -> C tau (mu(nu) over bar (mu)nu(tau), pi nu(tau), rho nu(tau))(nu) over bar (tau), reactions. These differential decay widths could be measured in the near future with certain precision. The first two contain information on the transverse tau-spin, tau-angular and tau-angular-spin asymmetries of the H-b -> H-c tau(nu) over bar (tau) parent decay and, from a dynamical point of view, they are richer than the commonly used one, d(2)Gamma(d)/(d omega dE(d)), since the latter only depends on the tau longitudinal polarization. We pay attention to the deviations with respect to the predictions of the standard model (SM) for these new observables, considering new physics (NP) operators constructed using both right- and left-handed neutrino fields, within an effective field-theory approach. We present results for Lambda(b) -> Lambda(c)tau (mu(nu) over bar (mu)nu(tau), pi nu(tau), rho nu(tau))(nu) over bar (tau) and (B) over bar -> D-(*()) tau (mu(nu) over bar (mu)nu(tau), pi nu(tau), rho nu(tau))(nu) over bar (tau) sequential decays and discuss their use to disentangle between different NP models. In this respect, we show that d Gamma(d)/d cos theta(d) , which should be measured with sufficiently good statistics, becomes quite useful, especially in the tau -> pi nu(tau) mode. The study carried out in this work could be of special relevance due to the recent LHCb measurement of the lepton flavor universality ratio R Lambda(c) in agreement with the SM. The experiment identified the tau using its hadron decay into pi(-)pi(+)pi(-)nu(tau), and this result for R Lambda(c )which is in conflict with the phenomenology from the b-meson sector, needs confirmation from other tau reconstruction channels.  
  Address [Penalva, Neus; Nieves, Juan] Inst Fis Corpuscular Ctr Mixto CSIC UV, Inst Invest Paterna, C Catedrat Jose Beltran 2, E-46980 Valencia, Spain, Email: neuspe@ific.uv.es;  
  Corporate Author Thesis  
  Publisher (up) Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000781361300001 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 5195  
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Author Albaladejo, M.; Nieves, J. url  doi
openurl 
  Title Compositeness of S-wave weakly-bound states from next-to-leading order Weinberg's relations Type Journal Article
  Year 2022 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C  
  Volume 82 Issue 8 Pages 724 - 12pp  
  Keywords  
  Abstract We discuss a model-independent estimator of the likelihood of the compositeness of a shallow S-wave bound or virtual state. The approach is based on an extension of Weinberg's relations in Weinberg (Phys Rev 137:B672, 1965) and it relies only on the proximity of the energy of the state to the two-hadron threshold to which it significantly couples. The scheme only makes use of the experimental scattering length and the effective range low energy parameters, and it is shown to be fully consistent for predominantly molecular hadrons. As explicit applications, we analyse the case of the deuteron, the S-1(0) nucleon virtual state and the exotic D-so(*)(2317)(+/-) , and find strong support to the molecular interpretation in all cases. Results are less conclusive for the D* (s0)(2317)+/-, since the binding energy of this state would be significantly higher than that of the deuteron, and the approach employed here is at the limit of its applicability. We also qualitatively address the case of the recently discovered T + cc state, within the isospin limit to avoid the complexity of the very close thresholds (DD)-D-0*+ and D + D*(0), which could mask the ingredients of the approach proposed in this work.  
  Address [Albaladejo, M.; Nieves, J.] Inst Invest Paterna, Inst Fis Corpuscular, Ctr Mixto CSIC UV, C Catedrat Jose Beltran 2, Valencia 46980, Spain, Email: Miguel.Albaladejo@ific.uv.es;  
  Corporate Author Thesis  
  Publisher (up) 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:000842040900001 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 5337  
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Author Abreu, L.M.; Albaladejo, M.; Feijoo, A.; Oset, E.; Nieves, J. url  doi
openurl 
  Title Shedding light on the X(3930) and X(3960) states with the B-> K- J/psi omega reaction Type Journal Article
  Year 2023 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C  
  Volume 83 Issue 4 Pages 309 - 11pp  
  Keywords  
  Abstract We have studied the contribution of the state X(3930), coming from the interaction of the D ($) over bar and D-s(+) D ($) over bar (s) channels, to the B- -> K- J/psi omega decay. The purpose of this work is to offer a complementary tool to see if the X(3930) state observed in the D+ D- channel is the same or not as the X(3960) resonance claimed by the LHCb Collaboration from a peak in the D-s(+) D s mass distribution around threshold. We present results for what we expect in the J/psi omega mass distribution in the B- -> K- J/psi omega decay and conclude that a clear signal should be seen around 3930 MeV. At the same time, finding no extra resonance signal at 3960 MeV would be a clear indication that there is not a new state at 3960 MeV, supporting the hypothesis that the near-threshold peaking structure peak in the D-s(+) D-s(-) mass distribution is only a manifestation of a resonance below threshold.  
  Address [Abreu, L. M.] Univ Fed Bahia, Inst Fis, Campus Univ Ondina, BR-40170115 Barreiras, BA, Brazil, Email: luciano.abreu@ufba.br;  
  Corporate Author Thesis  
  Publisher (up) 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:000977984500002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5531  
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Author Penalva, N.; Flynn, J.M.; Hernandez, E.; Nieves, J. url  doi
openurl 
  Title Study of new physics effects in (B)over-bars → Ds(*) τ-(ν)over-bar τ semileptonic decays using lattice QCD form factors and heavy quark effective theory Type Journal Article
  Year 2024 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 01 Issue 1 Pages 163 - 33pp  
  Keywords Effective Field Theories of QCD; Flavour Symmetries; Semi-Leptonic Decays; SMEFT  
  Abstract We benefit from the lattice QCD determination by the HPQCD of the Standard Model (SM) form factors for the (B) over bar (s) -> D-s [Phys. Rev. D101(2020) 074513] and the SM and tensor ones for the (B) over bar (s) -> D-s* (arXiv:2304.03137[hep-lat]) semileptonic decays, and the heavy quark effective theory (HQET) relations for the analogous B -> D-(*()) decays obtained by F.U. Bernlochner et al. in Phys. Rev. D95(2017) 115008, to extract the leading and sub-leading Isgur-Wise functions for the (B) over bar (s) -> D-s(()*()) decays. Further use of the HQET relations allows us to evaluate the corresponding scalar, pseudoscalar and tensor form factors needed for a phenomenological study of new physics (NP) effects on the (B) over bar (s) -> D-s(()*()) semileptonic decay. At present, the experimental values for the ratios R-D(*) = Gamma[ (B) over bar -> D-(*())(tau- (nu) over bar tau)]/Gamma[(B) over bar -> D-(*())e(-)(mu(-)) (nu) over bar (e(mu))]are the best signal in favor of lepton flavor universality violation (LFUV) seen in charged current (CC) b -> c decays. In this work we conduct a study of NP effects on the (B) over bar (s) -> D-s(()*()) tau(-)(tau) semileptonic decays by comparing tau spin, angular and spin-angular asymmetry distributions obtained within the SM and three different NP scenarios. As expected from SU(3) light-flavor symmetry, we get results close to the ones found in a similar analysis of the (B) over bar -> D-(*()) case. The measurement of the (B) over bar (s) -> D-s(()*())(l (nu) over bar tau) semileptonic decays, which is within reach of present experiments, could then be of relevance in helping to establish or rule out LFUV in CC b -> c transitions.  
  Address [Penalva, Neus; Nieves, Juan] Ctr Mixto CSIC UV, Inst Fis Corpuscular, Inst Invest Paterna, C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: neus.penalva@icc.ub.edu;  
  Corporate Author Thesis  
  Publisher (up) Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001152794800001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5922  
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Author Albertus, C.; Hernandez, E.; Nieves, J. url  doi
openurl 
  Title Exclusive c -> s, d Semileptonic Decays of Spin-1/2 and Spin-3/2 cb Baryons Type Journal Article
  Year 2014 Publication Few-Body Systems Abbreviated Journal Few-Body Syst.  
  Volume 55 Issue 8-10 Pages 767-771  
  Keywords  
  Abstract We present results for exclusive semileptonic decay widths of ground state spin-1/2 and spin-3/2 cb baryons corresponding to a c -> s, d transition at the quark level. The relevance of hyperfine mixing in spin-1/2 cb baryons is shown. Our form factors are compatible with heavy quark spin symmetry constraints obtained in the infinite heavy quark mass limit.  
  Address [Albertus, C.] Univ Granada, Fac Ciencias, Dept Fis Atom Mol & Nucl, E-18071 Granada, Spain, Email: albertus@ugr.es;  
  Corporate Author Thesis  
  Publisher (up) Springer Wien Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0177-7963 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000339828900036 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 1865  
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