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Author (up) 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 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  
Permanent link to this record
 

 
Author (up) 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 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  
Permanent link to this record
 

 
Author (up) Nieves, J.; Pavao, R.; Tolos, L. url  doi
openurl 
  Title Omega(c) excited states within a SU(6)(lsf) x HQSS model Type Journal Article
  Year 2018 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C  
  Volume 78 Issue 2 Pages 114 - 10pp  
  Keywords  
  Abstract We have reviewed the renormalization procedure used in the unitarized coupled-channel model of Romanets et al. (Phys Rev D 85: 114032, 2012), and its impact in the C = 1, S = -2, and I = 0 sector, where five Omega((*))(c) states have been recently observed by the LHCb Collaboration. The meson-baryon interactions used in the model are consistent with both chiral and heavy-quark spin symmetries, and lead to a successful description of the observed lowest-lying odd parity resonances Lambda(c)(2595) and Lambda(c)(2625), and Lambda(b)(5912) and Lambda(b)(5920) resonances. We show that some (probably at least three) of the states observed by LHCb will also have odd parity and J = 1/2 or J = 3/2, belonging two of them to the same SU(6)(light-spin-flavor) x HQSS multiplets as the latter charmed and beauty Lambda baryons.  
  Address [Nieves, J.; Pavao, R.] CSIC UV, Ctr Mixto, Inst Fis Corpuscular, Inst Invest Paterna, Aptdo 22085, Valencia 46071, Spain, Email: tolos@th.physik.uni-frankfurt.de  
  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:000428547200001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3533  
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Author (up) Nieves, J.; Pavon Valderrama, M. url  doi
openurl 
  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 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 (up) Nieves, J.; Pich, A.; Ruiz Arriola, E. url  doi
openurl 
  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 799  
Permanent link to this record
 

 
Author (up) Nieves, J.; Ruiz Simo, I.; Vicente Vacas, M.J. url  doi
openurl 
  Title Two particle-hole excitations in charged current quasielastic antineutrino-nucleus scattering Type Journal Article
  Year 2013 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 721 Issue 1-3 Pages 90-93  
  Keywords  
  Abstract We evaluate the quasielastic and multinucleon contributions to the antineutrino-nucleus scattering cross section and compare our results with the recent MiniBooNE data. We use a local Fermi gas model that includes RPA correlations and gets the multinucleon part from a systematic many body expansion of the W boson selfenergy in the nuclear medium. The same model had been quite successful for the neutrino cross section and contains no new parameters. We have also analyzed the relevance of 2p2h events for the antineutrino energy reconstruction.  
  Address Univ Valencia, Inst Invest Paterna, Inst Fis Corpuscular IFIC, Ctr Mixto,CSIC, 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:000317326100013 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1425  
Permanent link to this record
 

 
Author (up) Nieves, J.; Ruiz Simo, I.; Vicente Vacas, M.J. url  doi
openurl 
  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 903  
Permanent link to this record
 

 
Author (up) Nieves, J.; Ruiz Simo, I.; Vicente Vacas, M.J. url  doi
openurl 
  Title Inclusive charged-current neutrino-nucleus reactions Type Journal Article
  Year 2011 Publication Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 83 Issue 4 Pages 045501 - 19pp  
  Keywords  
  Abstract We present a model for weak charged-current induced nuclear reactions at energies of interest for current and future neutrino oscillation experiments. This model is a natural extension of the work in Refs. [1,2], where the quasielastic contribution to the inclusive electron and neutrino scattering on nuclei was analyzed. The model is based on a systematic many-body expansion of the gauge boson absorption modes that includes one, two, and even three-body mechanisms, as well as the excitation of Delta isobars. The whole scheme has no free parameters, besides those previously adjusted to the weak pion production off the nucleon cross sections in the deuteron, since all nuclear effects were set up in previous studies of photon, electron, and pion interactions with nuclei. We have discussed at length the recent charged-current quasielastic MiniBooNE cross section data, and showed that two-nucleon knockout mechanisms are essential to describing these measurements.  
  Address [Nieves, J.] Univ Valencia, CSIC, Inst Invest Paterna, Inst Fis Corpuscular IFIC,Ctr Mixto, 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 0556-2813 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000289192700004 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 594  
Permanent link to this record
 

 
Author (up) Nieves, J.; Sanchez, F.; Ruiz Simo, I.; Vicente Vacas, M.J. url  doi
openurl 
  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 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 (up) Nieves, J.; Sobczyk, J.E. url  doi
openurl 
  Title In medium dispersion relation effects in nuclear inclusive reactions at intermediate and low energies Type Journal Article
  Year 2017 Publication Annals of Physics Abbreviated Journal Ann. Phys.  
  Volume 383 Issue Pages 455-496  
  Keywords Neutrino-nucleus scattering; Quasielastic mechanism; Spectral function; RPA; Muon capture; Radiative pion capture  
  Abstract In a well-established many-body framework, successful in modeling a great variety of nuclear processes, we analyze the role of the spectral functions (SFs) accounting for the modifications of the dispersion relation of nucleons embedded in a nuclear medium. We concentrate in processes mostly governed by one-body mechanisms, and study possible approximations to evaluate the particle hole propagator using SFs. We also investigate how to include together SFs and long-range RPA-correlation corrections in the evaluation of nuclear response functions, discussing the existing interplay between both type of nuclear effects. At low energy transfers (<= 50 MeV), we compare our predictions for inclusive muon and radiative pion captures in nuclei, and charge-current (CC) neutrino-nucleus cross sections with experimental results. We also present an analysis of intermediate energy quasi-elastic neutrino scattering for various targets and both neutrino and antineutrino CC driven processes. In all cases, we pay special attention to estimate the uncertainties affecting the theoretical predictions. In particular, we show that errors on the a,,sigma(mu)/sigma(e) ratio are much smaller than 5%, and also much smaller than the size of the SF+RPA nuclear corrections, which produce significant effects, not only in the individual cross sections, but also in their ratio for neutrino energies below 400 MeV. These latter nuclear corrections, beyond Pauli blocking, turn out to be thus essential to achieve a correct theoretical understanding of this ratio of cross sections of interest for appearance neutrino oscillation experiments. We also briefly compare our SF and RPA results to predictions obtained within other representative approaches.  
  Address [Nieves, Juan] Univ Valencia, CSIC,Ctr Mixto, Inst Invest Paterna, Inst Fis Corpuscular IFIC, Apartado 22085, E-46071 Valencia, Spain, Email: jmnieves@ific.uv.es  
  Corporate Author Thesis  
  Publisher Academic Press Inc Elsevier Science Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-4916 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000407667300025 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3244  
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