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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 Electromagnetic form factors; Chiral lagrangians; Dispersion relations; Hyperons; Charge distribution
Abstract (up) 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 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 0375-9474 ISBN Medium
Area Expedition Conference
Notes WOS:000404199900002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3188
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Author Pich, A.; Rosell, I.; Santos, J.; Sanz-Cillero, J.J.
Title Fingerprints of heavy scales in electroweak effective Lagrangians Type Journal Article
Year 2017 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages 012 - 60pp
Keywords Beyond Standard Model; Chiral Lagrangians; Higgs Physics; Technicolor and Composite Models
Abstract (up) The couplings of the electroweak effective theory contain information on the heavy-mass scales which are no-longer present in the low-energy Lagrangian. We build a general effective Lagrangian, implementing the electroweak chiral symmetry breaking SU(2)(L) circle times SU(2)(R) -> SU(2)(L+R), which couples the known particle fields to heavier states with bosonic quantum numbers J(P) = 0(+/-) and 1(+/-). We consider colour-singlet heavy fields that are in singlet or triplet representations of the electroweak group. Integrating out these heavy scales, we analyze the pattern of low-energy couplings among the light fields which are generated by the massive states. We adopt a generic non-linear realization of the electroweak symmetry breaking with a singlet Higgs, without making any assumption about its possible doublet structure. Special attention is given to the different possible descriptions of massive spin-1 fields and the differences arising from naive implementations of these formalisms, showing their full equivalence once a proper short-distance behaviour is required.
Address [Pich, Antonio; Santos, Joaquin] Univ Valencia, CSIC, IFIC, Dept Fis Teor, Apt Correus 22085, E-46071 Valencia, Spain, Email: pich@ific.uv.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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000398449400004 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3074
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Author Cirigliano, V.; Gisbert, H.; Pich, A.; Rodriguez-Sanchez, A.
Title Isospin-violating contributions to epsilon '/epsilon Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue 2 Pages 032 - 44pp
Keywords Chiral Lagrangians; CP violation; Effective Field Theories; Kaon Physics
Abstract (up) The known isospin-breaking contributions to the K -> pi pi amplitudes are reanalyzed, taking into account our current understanding of the quark masses and the relevant non-perturbative inputs. We present a complete numerical reappraisal of the direct CP-violating ratio is an element of(')/is an element of, where these corrections play a quite significant role. We obtain the Standard Model prediction Re (is an element of(')/is an element of) = (14 +/- 5) <bold> </bold>10(-4), which is in very good agreement with the measured ratio. The uncertainty, which has been estimated conservatively, is dominated by our current ignorance about 1/N-C-suppressed contributions to some relevant chiral-perturbation-theory low-energy constants.
Address [Cirigliano, V.] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA, Email: cirigliano@lanl.gov;
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000515816800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4304
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Author Chen, Y.H.; Yao, D.L.; Zheng, H.Q.
Title A Study of rho-omega Mixing in Resonance Chiral Theory Type Journal Article
Year 2018 Publication Communications in Theoretical Physics Abbreviated Journal Commun. Theor. Phys.
Volume 69 Issue 1 Pages 50-58
Keywords Chiral Lagrangians; vector mesons; 1/N-C expansion
Abstract (up) The strong and electromagnetic corrections to rho-omega mixing are calculated using an SU(2) version of resonance chiral theory up to next-to-leading orders in 1/N-C expansion, respectively. Up to our accuracy, the effect of the momentum dependence of rho-omega mixing is incorporated due to the inclusion of loop contributions. We analyze the impact of rho-omega mixing on the pion vector form factor by performing numerical fit to the data extracted from e(+)e(-) -> pi(+)pi(-) and tau -> nu(tau)2 pi, while the decay width of omega -> pi(+)pi(-) is taken into account as a constraint. It is found that the momentum dependence is significant in a good description of the experimental data. In addition, based on the fitted values of the involved parameters, we analyze the decay width of omega -> pi(+)pi(-), which turns out to be highly dominated by the rho-omega mixing effect.
Address [Chen, Yun-Hua] Univ Sci & Technol Beijing, Sch Math & Phys, Beijing 100083, Peoples R China, Email: yhchen@ustb.edu.cn;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0253-6102 ISBN Medium
Area Expedition Conference
Notes WOS:000422832600010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3453
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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 Hadron tau decays; Chiral Lagrangians; QCD; 1/N expansion
Abstract (up) 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 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:000275148800010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 488
Permanent link to this record