| Records |
| Author |
Nieves, J.; Pavao, R.; Tolos, L. |
| 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  |
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| 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 |
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Thesis |
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| Publisher |
Springer |
Place of Publication |
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| Language |
English |
Summary Language |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1434-6044 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000428547200001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3533 |
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| Author |
Sobczyk, J.E.; Rocco, N.; Lovato, A.; Nieves, J. |
| Title |
Scaling within the spectral function approach |
Type |
Journal Article |
| Year |
2018 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
97 |
Issue |
3 |
Pages |
035506 - 15pp |
| Keywords |
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| Abstract |
Scaling features of the nuclear electromagnetic response functions unveil aspects of nuclear dynamics that are crucial for interpreting neutrino-and electron-scattering data. In the large momentum-transfer regime, the nucleon-density response function defines a universal scaling function, which is independent of the nature of the probe. In this work, we analyze the nucleon-density response function of C-12, neglecting collective excitations. We employ particle and hole spectral functions obtained within two distinct many-body methods, both widely used to describe electroweak reactions in nuclei. We show that the two approaches provide compatible nucleon-density scaling functions that for large momentum transfers satisfy first-kind scaling. Both methods yield scaling functions characterized by an asymmetric shape, although less pronounced than that of experimental scaling functions. This asymmetry, only mildly affected by final state interactions, is mostly due to nucleon-nucleon correlations, encoded in the continuum component of the hole spectral function. |
| Address |
[Sobczyk, J. E.; Nieves, J.] Univ Valencia, Inst Invest Paterna, Inst Fis Corpuscular IFIC, Ctr Mixto CSIC, Apartado 22085, E-46071 Valencia, Spain |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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| Language |
English |
Summary Language |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
2469-9985 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000428505400006 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3544 |
| Permanent link to this record |
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| Author |
Yao, D.L.; Fernandez-Soler, P.; Albaladejo, M.; Guo, F.K.; Nieves, J. |
| Title |
Heavy-to-light scalar form factors from Muskhelishvili-Omnes dispersion relations |
Type |
Journal Article |
| Year |
2018 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
| Volume |
78 |
Issue |
4 |
Pages |
310 - 26pp |
| Keywords |
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| Abstract |
By solving the Muskhelishvili-Omnes integral equations, the scalar form factors of the semileptonic heavy meson decays D -> pi(l) over bar nu(l), D -> (K) over bar(l) over bar nu(l), (K) over bar -> pi(l) over bar nu(l) and (B) over bar (s) -> Kl (nu) over bar (l) are simultaneously studied. As input, we employ unitarized heavy meson-Goldstone boson chiral coupled-channel amplitudes for the energy regions not far from thresholds, while, at high energies, adequate asymptotic conditions are imposed. The scalar form factors are expressed in terms of Omn\`es matrices multiplied by vector polynomials, which contain some undetermined dispersive subtraction constants. We make use of heavy quark and chiral symmetries to constrain these constants, which are fitted to lattice QCD results both in the charm and the bottom sectors, and in this latter sector to the light-cone sum rule predictions close to q(2)=0 as well. We find a good simultaneous description of the scalar form factors for the four semileptonic decay reactions. From this combined fit, and taking advantage that scalar and vector form factors are equal at q(2)=0, we obtain |V-cd| = 0.244 +/- 0.022, |V-cs| = 0.945 +/- 0.041 and |V-ub| = (4.3 +/- 0.7)x10(-3) for the involved Cabibbo-Kobayashi-Maskawa (CKM) matrix elements. In addition, we predict the following vector form factors at q(2) = 0: |f(+)(D ->eta)(0)| = 0.01 +/- 0.05, |f(+)(Ds ->eta)(0)| = 0.50 +/- 0.08, |f(+)(Ds ->eta)(0)| = 0.73 +/- 0.03 and|f(+)((B) over bar ->eta)(0)| = 0.82 +/- 0.08, which might serve as alternatives to determine the CKM elements when experimental measurements of the corresponding differential decay rates become available. Finally, we predict the different form factors above the q(2)-regions accessible in the semileptonic decays, up to moderate energies amenable to be described using the unitarized coupled-channel chiral approach. |
| Address |
[Yao, D. -L.; Fernandez-Soler, P.; Nieves, J.] UV, Inst Invest Paterna, Ctr Mixto, Inst Fis Corpuscular,CSIC, Apartado 22085, Valencia, Spain, Email: deliang.yao@ific.uv.es; |
| Corporate Author |
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Thesis |
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| Publisher |
Springer |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1434-6044 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000430575000006 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3568 |
| Permanent link to this record |
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| Author |
Albaladejo, M.; Fernandez-Soler, P.; Nieves, J.; Ortega, P.G. |
| Title |
Contribution of constituent quark model c(s)over-bar states to the dynamics of the D*s0 (2317) and Ds1(2460) resonances |
Type |
Journal Article |
| Year |
2018 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
| Volume |
78 |
Issue |
9 |
Pages |
722 - 22pp |
| Keywords |
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| Abstract |
The masses of the D*(s0) (2317) and D-s1(2460) resonances lie below the DK and D* K thresholds respectively, which contradicts the predictions of naive quark models and points out to non-negligible effects of the D(*) K loops in the dynamics of the even-parity scalar (J(pi) = 0(+)) and axial-vector (J(pi) = 1(+)) c (s) over bar systems. Recent lattice QCD studies, incorporating the effects of the D(*) K channels, analyzed these spin-parity sectors and correctly described the D*(s0)(2317) – D-s1(2460) mass splitting. Motivated by such works, we study the structure of the D*(s0)(2317) and D-s1(2460) resonances in the framework of an effective field theory consistent with heavy quark spin symmetry, and that incorporates the interplay between D(*) K meson-meson degrees of freedom and bare P-wave c (s) over bar states predicted by constituent quark models. We extend the scheme to finite volumes and fit the strength of the coupling between both types of degrees of freedom to the available lattice levels, which we successfully describe. We finally estimate the size of the D(*) K two-meson components in the D*(s0)(2317) and D-s1(2460) resonances, and we conclude that these states have a predominantly hadronic-molecular structure, and that it should not be tried to accommodate these mesons within c (s) over bar constituent quark model patterns. |
| Address |
[Albaladejo, Miguel] Univ Murcia, Dept Fis, E-30071 Murcia, Spain, Email: albaladejo@um.es; |
| Corporate Author |
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Thesis |
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| Publisher |
Springer |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1434-6044 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000443822000003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
3714 |
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| Author |
Sobczyk, J.E.; Hernandez, E.; Nakamura, S.X.; Nieves, J.; Sato, T. |
| Title |
Angular distributions in electroweak pion production off nucleons: Odd parity hadron terms, strong relative phases, and model dependence |
Type |
Journal Article |
| Year |
2018 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
98 |
Issue |
7 |
Pages |
073001 - 39pp |
| Keywords |
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| Abstract |
The study of pion production in nuclei is important for signal and background determinations in current and future neutrino oscillation experiments. The first step, however, is to understand the pion production reactions at the free nucleon level. We present an exhaustive study of the charged-current and neutral-current neutrino and antineutrino pion production off nucleons, paying special attention to the angular distributions of the outgoing pion. We show, using general arguments, that parity violation and time-reversal odd correlations in the weak differential cross sections are generated from the interference between different contributions to the hadronic current that are not relatively real. Next, we present a detailed comparison of three state-of-the-art, microscopic models for electroweak pion production off nucleons, and we also confront their predictions with polarized electron data, as a test of the vector content of these models. We also illustrate the importance of carrying out a comprehensive test at the level of outgoing pion angular distributions, going beyond comparisons done for partially integrated cross sections, where model differences cancel to a certain extent. Finally, we observe that all charged and neutral current distributions show sizable anisotropies, and identify channels for which parity-violating effects are clearly visible. Based on the above results, we conclude that the use of isotropic distributions for the pions in the center of mass of the final pion-nucleon system, as assumed by some of the Monte Carlo event generators, needs to be improved by incorporating the findings of microscopic calculations. |
| Address |
[Sobczyk, J. E.; Nieves, J.] Univ Valencia, Ctr Mixto CSIC, Inst Fis Corpuscular IFIC, Inst Invest Paterna, Apartado 22085, E-46071 Valencia, Spain |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
2470-0010 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000446557200001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3751 |
| Permanent link to this record |
