Records |
Author |
Alarcon, J.M.; Hiller Blin, A.N.; Vicente Vacas, M.J.; Weiss, C. |
Title |
Peripheral transverse densities of the baryon octet from chiral effective field theory and dispersion analysis |
Type |
Journal Article |
Year |
2017 |
Publication |
Nuclear Physics A |
Abbreviated Journal |
Nucl. Phys. A |
Volume |
964 |
Issue |
|
Pages |
18-54 |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Electromagnetic form factors; Chiral lagrangians; Dispersion relations; Hyperons; Charge distribution |
Abstract |
The baryon electromagnetic form factors are expressed in terms of two-dimensional densities describing the distribution of charge and magnetization in transverse space at fixed light-front time. We calculate the transverse densities of the spin-1/2 flavor-octet baryons at peripheral distances b = O(M-pi(-1)) using methods of relativistic chiral effective field theory (chi EFT) and dispersion analysis. The densities are represented as dispersive integrals over the imaginary parts of the form factors in the timelike region (spectral functions). The isovector spectral functions on the two-pion cut t > 4 M-pi(2) are calculated using relativistic chi EFT including octet and decuplet baryons. The chi EFT calculations are extended into the rho meson mass region using an N / D method that incorporates the pion electromagnetic form factor data. The isoscalar spectral functions are modeled by vector meson poles. We compute the peripheral charge and magnetization densities in the octet baryon states, estimate the uncertainties, and determine the quark flavor decomposition. The approach can be extended to baryon form factors of other operators and the moments of generalized parton distributions. |
Address |
[Alarcon, J. M.] Univ Bonn, Helmholtz Inst Strahlen & Kernphys, D-53115 Bonn, Germany, Email: alarcon@jlab.org |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
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 |
0375-9474 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000404199900002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3188 |
Permanent link to this record |
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Author |
Gomez Dumm, D.; Roig, P.; Pich, A.; Portoles, J. |
Title |
tau -> pi pi pi nu(tau) decays and the a(1)(1260) off-shell width revisited |
Type |
Journal Article |
Year |
2010 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
685 |
Issue |
2-3 |
Pages |
158-164 |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Hadron tau decays; Chiral Lagrangians; QCD; 1/N expansion |
Abstract |
The tau -> pi pi pi nu(tau) decay is driven by the hadronization of the axial-vector current. Within the resonance chiral theory, and considering the large-N-C expansion, this process has been studied in Ref. [1] (D. Gomez Dumm, A. Pich, J. Portoles, 2004). In the light of later developments we revise here this previous work by including a new off-shell width for the lightest a(1) resonance that provides a good description of the tau -> pi pi pi nu(tau) spectrum and branching ratio. We also consider the role of the rho(1450) resonance in these observables. Thus we bring in an overall description of the tau -> pi pi pi nu(tau) process in excellent agreement with our present experimental knowledge. |
Address |
[Pich, A.; Portoles, J.] Univ Valencia, CSIC, Dept Fis Teor, IFIC, E-46071 Valencia, Spain, Email: Jorge.Portoles@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
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 |
0370-2693 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
ISI:000275148800010 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
488 |
Permanent link to this record |
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Author |
Pich, A.; Rosell, I.; Sanz-Cillero, J.J. |
Title |
One-loop calculation of the oblique S parameter in higgsless electroweak models |
Type |
Journal Article |
Year |
2012 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
08 |
Issue |
8 |
Pages |
106 - 34pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Higgs Physics; Beyond Standard Model; Chiral Lagrangians; Technicolor and Composite Models |
Abstract |
We present a one-loop calculation of the oblique S parameter within Higgsless models of electroweak symmetry breaking and analyze the phenomenological implications of the available electroweak precision data. We use the most general effective Lagrangian with at most two derivatives, implementing the chiral symmetry breaking SU(2)(L) circle times SU(2)(R) -> SU(2)(L+R) with Goldstones, gauge bosons and one multiplet of vector and axial-vector massive resonance states. Using the dispersive representation of Peskin and Takeuchi and imposing the short-distance constraints dictated by the operator product expansion, we obtain S at the NLO in terms of a few resonance parameters. In asymptotically-free gauge theories, the final result only depends on the vector-resonance mass and requires M-V > 1.8TeV (3.8TeV) to satisfy the experimental limits at the 3 sigma (1 sigma) level; the axial state is always heavier, we obtain M-A > 2.5TeV (6.6TeV) at 3 sigma (1 sigma). In strongly-coupled models, such as walking or conformal technicolour, where the second Weinberg sum rule does not apply, the vector and axial couplings are not determined by the short-distance constraints; but one can still derive a lower bound on S, provided the hierarchy M-V < M-A remains valid. Even in this less constrained situation, we find that in order to satisfy the experimental limits at 3 sigma one needs M-V,M-A > 1.8TeV. |
Address |
[Pich, A.; Rosell, I.] Univ Valencia, CSIC, IFIC, Dept Fis Teor, E-46071 Valencia, Spain, Email: antonio.pich@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 |
1126-6708 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000309883200063 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
1217 |
Permanent link to this record |
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Author |
Pich, A.; Rosell, I.; Sanz-Cillero, J.J. |
Title |
Oblique S and T constraints on electroweak strongly-coupled models with a light Higgs |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
01 |
Issue |
1 |
Pages |
157 - 35pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Higgs Physics; Beyond Standard Model; Chiral Lagrangians; Technicolor and Composite Models |
Abstract |
Using a general effective Lagrangian implementing the chiral symmetry breaking SU(2)(L) circle times SU(2)(R) -> SU(2)(L+R), we present a one-loop calculation of the oblique S and T parameters within electroweak strongly-coupled models with a light scalar. Imposing a proper ultraviolet behaviour, we determine S and T at next-to-leading order in terms of a few resonance parameters. The constraints from the global fit to electroweak precision data force the massive vector and axial-vector states to be heavy, with masses above the TeV scale, and suggest that the W+W- and and ZZ couplings of the Higgs-like scalar should be close to the Standard Model value. Our findings are generic, since they only rely on soft requirements on the short-distance properties of the underlying strongly-coupled theory, which are widely satisfied in more specific scenarios. |
Address |
[Pich, A.; Rosell, I.] Univ Valencia, CSIC, IFIC, Dept Fis Teor, E-46071 Valencia, Spain, Email: antonio.pich@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 |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000346240600006 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
2059 |
Permanent link to this record |
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Author |
Baron, R.; Boucaud, P.; Carbonell, J.; Deuzeman, A.; Drach, V.; Farchioni, F.; Gimenez, V.; Herdoiza, G.; Jansen, K.; McNeile, C.; Michael, C.; Montvay, I.; Palao, D.; Pallante, E.; Pene, O.; Urbach, C.; Wagner, M.; Wenger, U. |
Title |
Light hadrons from lattice QCD with light (u, d), strange and charm dynamical quarks |
Type |
Journal Article |
Year |
2010 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
06 |
Issue |
6 |
Pages |
111 - 31pp |
Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Lattice QCD; Chiral Lagrangians |
Abstract |
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Address |
[Deuzeman, A.; Pallante, E.; Urbach, C.] Univ Groningen, Ctr Theoret Phys, NL-9747 AG Groningen, Netherlands, Email: e.pallante@rug.nl |
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 |
1126-6708 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
ISI:000279630800058 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
415 |
Permanent link to this record |