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Author Hidalgo-Duque, C.; Nieves, J.; Ozpineci, A.; Zamiralov, V.
Title X(3872) and its partners in the heavy quark limit of QCD Type Journal Article
Year 2013 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume (down) 727 Issue 4-5 Pages 432-437
Keywords
Abstract In this Letter, we propose interpolating currents for the X(3872) resonance, and show that, in the heavy quark limit of QCD, the X(3872) state should have degenerate partners, independent of its internal structure. Magnitudes of possible I = 0 and I = 1 components of the X(3872) are also discussed.
Address [Hidalgo-Duque, C.; Nieves, J.; Ozpineci, A.] Ctr Mixto CSIC UV, Inst Invest Paterna, Inst Fis Corpuscular, Valencia 46071, Spain, Email: carloshd@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:000328722500011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1665
Permanent link to this record
 
 
Author Nieves, J.; Ruiz Simo, I.; Vicente Vacas, M.J.
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 (down) 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 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 (down) 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 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 (down) 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 828
Permanent link to this record
 
 
Author Garcia-Recio, C.; Nieves, J.; Tolos, L.
Title D mesic nuclei Type Journal Article
Year 2010 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume (down) 690 Issue 4 Pages 369-375
Keywords Charm; Mesic nuclei; Heavy quark symmetry
Abstract The energies and widths of several D-0 meson bound states for different nuclei are obtained using a D-meson selfenergy in the nuclear medium, which is evaluated in a selfconsistent manner using techniques of unitarized coupled-channel theory. The kernel of the meson-baryon interaction is based on a model that treats heavy pseudoscalar and heavy vector mesons on equal footing, as required by heavy quark symmetry. We find D-0 bound states in all studied nuclei, from C-12 up to Pb-208. The inclusion of vector mesons is the keystone for obtaining an attractive D-nucleus interaction that leads to the existence of D-0-nucleus bound states, as compared to previous studies based on SU(4) flavor symmetry. In some cases, the half widths are smaller than the separation of the levels, what makes possible their experimental observation by means of a nuclear reaction. This can be of particular interest for the future PANDA@FAIR physics program. We also find a D+ bound state in C-12, but it is too broad and will have a significant overlap with the energies of the continuum.
Address [Garcia-Recio, C.] Univ Granada, Dept Fis Atom Mol & Nucl, E-18071 Granada, Spain, Email: g_recio@ugr.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 ISI:000279835300007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 407
Permanent link to this record
 
 
Author Albertus, C.; Hernandez, E.; Nieves, J.
Title Hyperfine mixing in electromagnetic decay of doubly heavy bc baryons Type Journal Article
Year 2010 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume (down) 690 Issue 3 Pages 265-271
Keywords Hyperfine mixing; Double heavy bc baryons
Abstract We investigate the role of hyperfine mixing in the electromagnetic decay of ground state doubly heavy bc baryons. As in the case of a previous calculation on b -> c semileptonic decays of doubly heavy baryons, we find large corrections to the electromagnetic decay widths due to this mixing. Contrary to the weak case just mentioned, we find here that one cannot use electromagnetic width relations obtained in the infinite heavy quark mass limit to experimentally extract information on the admixtures in a model independent way.
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 ISI:000279388800012 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 416
Permanent link to this record
 
 
Author Albertus, C.; Hernandez, E.; Nieves, J.
Title Hyperfine mixing in b -> c semileptonic decay of doubly heavy baryons Type Journal Article
Year 2010 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume (down) 683 Issue 1 Pages 21-25
Keywords
Abstract We qualitatively corroborate the results of [W. Roberts, M. Pervin, Int. J. Mod. Phys. A 24 (2009) 2401] according to which hyperfine mixing greatly affects the decay widths of b -> c semileptonic decays involving doubly heavy bc baryons. However, our predictions for the decay widths of the unmixed states differ from those reported in the work of Roberts and Pervin by a factor of 2, and this discrepancy translates to the mixed case. We further show that the predictions of heavy quark spin symmetry, might be used in the future to experimentally extract information on the admixtures in the actual physical bc baryons, in a model independent manner.
Address [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 ISI:000274129600005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 501
Permanent link to this record
 
 
Author Nieves, J.; Sobczyk, J.E.
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 (down) 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
Permanent link to this record
 
 
Author Nieves, J.; Feijoo, A.; Albaladejo, M.; Du, M.L.
Title Lowest-lying 1/2- and 3/2- ΛQ resonances: From the strange to the bottom sectors Type Journal Article
Year 2024 Publication Progress in Particle and Nuclear Physics Abbreviated Journal Prog. Part. Nucl. Phys.
Volume (down) 137 Issue Pages 104118 - 23pp
Keywords Heavy quark symmetry; Constituent quark-model; Molecule; Charmed; Bottomed
Abstract We present a detailed study of the lowest-lying 1/2(-) and 3/2(-) Lambda Q resonances both in the heavy 2 2 quark (bottom and charm) and the strange sectors. We have paid special attention to the interplay between the constituent quark-model and chiral baryon-meson degrees of freedom, which are coupled using a unitarized scheme consistent with leading-order heavy quark symmetries. We show that the Lambda(b)(5912) [J(P) = 1/2(-)], Lambda(b)(5920) [J(P) = 3/2(-)] and the Lambda(c)(2625) [J(P) = 3/2-], and the Lambda(1520) [J(P) = 3/2(-)] admitting larger breaking corrections, are heavyquark spin-flavor siblings. They can be seen as dressed quark-model states with Sigma Q(()*()) pi molecular components of the order of 30%. The J(P)=1(-) Lambda(2595) has, however, a higher molecular 2 probability of at least 50%, and even values greater than 70% can be easily accommodated. This is because it is located almost on top of the threshold of the Sigma(c)pi pair, which largely influences its properties. Although the light degrees of freedom in this resonance would be coupled to spin-parity 1(-) as in the Lambda(b)(5912), Lambda(b)(5920) and Lambda(c)(2625), the Lambda(c)(2595) should not be considered as a heavy-quark spin-flavor partner of the former ones. We also show that the Lambda(1405) chiral two-pole pattern does not have analogs in the 1 – charmed and bottomed sectors, because the 2 N D-(*()) and N (B) over bar (()*()) channels do not play for heavy quarks the decisive role that the N (K) over bar does in the strange sector, and the notable influence of the bare quark-model states for the charm and bottom resonances. Finally, we predict the existence of two Lambda(b)(6070) and two Lambda(c)(2765) heavy-quark spin and flavor sibling odd parity states.
Address [Nieves, J.; Feijoo, A.; Albaladejo, M.] Inst Fis Corpuscular, Ctr Mixto, CSIC UV, Valencia, Spain, Email: jmnieves@ific.uv.es;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0146-6410 ISBN Medium
Area Expedition Conference
Notes WOS:001243410100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6153
Permanent link to this record
 
 
Author Du, M.L.; Filin, A.; Baru, V.; Dong, X.K.; Epelbaum, E.; Guo, F.K.; Hanhart, C.; Nefediev, A.; Nieves, J.; Wang, Q.
Title Role of Left-Hand Cut Contributions on Pole Extractions from Lattice Data: Case Study for Tcc(3875)+ Type Journal Article
Year 2023 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume (down) 131 Issue 13 Pages 131903 - 7pp
Keywords
Abstract We discuss recent lattice data for the T_{cc}(3875)^{+} state to stress, for the first time, a potentially strong impact of left-hand cuts from the one-pion exchange on the pole extraction for near-threshold exotic states. In particular, if the left-hand cut is located close to the two-particle threshold, which happens naturally in the DD^{*} system for the pion mass exceeding its physical value, the effective-range expansion is valid only in a very limited energy range up to the cut and as such is of little use to reliably extract the poles. Then, an accurate extraction of the pole locations requires the one-pion exchange to be implemented explicitly into the scattering amplitudes. Our findings are general and potentially relevant for a wide class of hadronic near-threshold states.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes MEDLINE:37832010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6060
Permanent link to this record