| Records |
| Author |
Albertus, C.; Hernandez, E.; Nieves, J. |
| Title |
B -> rho semileptonic decays and vertical bar V-ub vertical bar |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume  |
90 |
Issue |
1 |
Pages |
013017 - 11pp |
| Keywords |
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| Abstract |
We reevaluate the B -> rho l(+) nu(l) decay width as a full B. pi pi iota(+)nu iota four-particle decay, in which the two final pions are produced via an intermediate. meson. The decay width can be written as a convolution of the B -> rho l(+) nu(l) decay width, for an off-shell., with the.. pp line shape. This allows us to fully incorporate the effects of the finite. meson width and a better comparison with actual experiments. We use an Omn s representation to provide the dependence of the B.. semileptonic form factors on q2. The Omn s subtraction constants and the overall normalization parameter jVubj are fitted to light cone sum rules and lattice QCD theoretical form-factor calculations, in the low and high q2 regions, respectively, together to the CLEO, BABAR, and Belle experimental partial branching fraction distributions. The extracted value from this global fit is jVubj d3.40 +/- 0.15_ x 10-3, in agreement with jVubj extracted using all other inputs in Cabibbo-Kobayashi-Maskawa fits and the exclusive semileptonic B. p channel, but showing a clear disagreement with jVubj extracted from inclusive semileptonic b. u decays. As estimated by [U.-G. Mei beta ner andW. Wang, J. High Energy Phys. 01 (2014) 107], taking into account the. meson width effects and the actual acceptance of the experiments is essential to render the jVubj determinations from exclusive B. p and B.. decays totally compatible. |
| Address |
[Albertus, C.] Univ Granada, Dept Fis Atom Nucl & Mol, E-18071 Granada, Spain |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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| Language |
English |
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Series Issue |
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Edition |
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| ISSN |
1550-7998 |
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:000339482900002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
1859 |
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| Author |
Ledwig, T.; Nieves, J.; Pich, A.; Ruiz Arriola, E.; Ruiz de Elvira, J. |
| Title |
Large-N-c naturalness in coupled-channel meson-meson scattering |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
90 |
Issue |
11 |
Pages |
114020 - 17pp |
| Keywords |
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| Abstract |
The analysis of hadronic interactions with effective field theory techniques is complicated by the appearance of a large number of low-energy constants, which are usually fitted to data. On the other hand, the large-N-c limit helps to impose natural short-distance constraints on these low-energy constants, providing a parameter reduction. A Bayesian interpretation of the expected 1/N-c accuracy allows for an easy and efficient implementation of these constraints, using an augmented chi(2). We apply this approach to the analysis of meson-meson scattering, in conjunction with chiral perturbation theory to one loop and coupled-channel unitarity, and show that it helps to largely reduce the many existing ambiguities and simultaneously provide an acceptable description of the available phase shifts. |
| Address |
[Ledwig, T.; Nieves, J.; Pich, A.] Univ Valencia, CSIC, IFIC, Dept Fis Teor, Valencia 46071, Spain |
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| Publisher |
Amer Physical Soc |
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English |
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Edition |
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| ISSN |
1550-7998 |
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:000348730800008 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2100 |
| Permanent link to this record |
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| Author |
Wang, E.; Xie, J.J.; Nieves, J. |
| Title |
Regge signatures from forward CLAS Lambda(1520) photoproduction data |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
90 |
Issue |
6 |
Pages |
065203 - 10pp |
| Keywords |
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| Abstract |
The γp→K+Λ(1520) reaction mechanism is investigated within a Regge--effective Lagrangian hybrid approach based on our previous study of this reaction [Physical Review C89, 015203 (2014)]. Near threshold and for large K+ angles, both the CLAS and LEPS data can be successfully described by considering the contributions from the contact, t-channel K¯ exchange, u-channel Λ(1115) hyperon pole, and the s-channel nucleon pole and N∗(2120) resonance contributions. However, for higher energies and forward K+ angles, systematic discrepancies with data appear, which hint the possible existence of sizable quark-gluon string mechanism effects. We show how the inclusion of a K¯ Regge--trajectory exchange in the t-channel leads to an efficient description of the Λ(1520) photoproduction channel over the whole energy and angular ranges accessible in the CLAS experiment. |
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Conference |
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| Notes |
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Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2135 |
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| Author |
Xie, J.J.; Wang, E.; Nieves, J. |
| Title |
Re-analysis of the A(1520) photoproduction reaction |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
89 |
Issue |
1 |
Pages |
015203 - 10pp |
| Keywords |
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| Abstract |
Based on previous studies that support the important role of the N*(2120)D-13 resonance in the gamma p -> K+ A(1520) reaction, we make a re-analysis of this A(1520) photoproduction reaction taking into account the recent CLAS differential cross-section data. In addition to the contact, t-channel (K) over bar exchange, s-channel nucleon pole, and N*(2120) [previously called N*(2080)] resonance contributions, which have been considered in previous works, we also study the u-channel A(1115) hyperon pole term. The latter mechanism has always been ignored in all theoretical analysis, which has mostly relied on the very forward K+ angular LEPS data. It is shown that when the contributions from the N*(2120) resonance and the A(1115) hyperon are taken into account, both the new CLAS and the previous LEPS data can be simultaneously described. We also show that the contribution from the u-channel A(1115) pole term produces an enhancement for large K+ angles, and it becomes more and more relevant as the photon energy increases, being essential to describe the CLAS differential cross sections at backward angles. Furthermore, we find that the new CLAS data also favor the existence of the N*(2120) resonance and that these measurements can be used to further constrain its properties. |
| Address |
[Xie, Ju-Jun] Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China, Email: xiejujun@impcas.ac.cn; |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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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 |
0556-2813 |
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:000332160300009 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1718 |
| Permanent link to this record |
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| Author |
Wang, E.; Alvarez-Ruso, L.; Nieves, J. |
| Title |
Photon emission in neutral-current interactions at intermediate energies |
Type |
Journal Article |
| Year |
2014 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
| Volume |
89 |
Issue |
1 |
Pages |
015503 - 21pp |
| Keywords |
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| Abstract |
Neutral-current photon emission reactions with nucleons and nuclei are studied. These processes are important backgrounds for nu(mu) -> nu(e) ((nu) over bar (mu) -> (nu) over bar (e)) appearance oscillation experiments where electromagnetic showers instigated by electrons (positrons) and photons are not distinguishable. At intermediate energies, these reactions are dominated by the weak excitation of the Delta(1232) resonance and its subsequent decay into N gamma. There are also nonresonant contributions that, close to threshold, are fully determined by the effective chiral Lagrangian of strong interactions. In addition, we have also included mechanisms mediated by nucleon excitations (N*) from the second resonance region above the Delta(1232). From these states, the contribution of the D-13 N*(1520) turns out to be sizable for (anti) neutrino energies above 1.5 GeV. We have extended the model to nuclear targets taking into account Pauli blocking, Fermi motion, and the in-medium Delta resonance broadening. We present our predictions for both the incoherent and coherent channels, showing the relevance of the nuclear corrections. We also discuss the target mass dependence of the cross sections. This study is important to reduce systematic effects in neutrino oscillation experiments. |
| Address |
[Wang, E.] Ctr Mixto Univ Valencia CSIC, Dept Fis Teor, Inst Invest Paterna, E-46071 Valencia, Spain |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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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 |
0556-2813 |
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:000332159800010 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
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| Call Number |
IFIC @ pastor @ |
Serial |
1719 |
| Permanent link to this record |
