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Author Gomez Dumm, D.; Noguera, S.; Scoccola, N.N.; Scopetta, S.
Title Pion distribution amplitude and the pion-photon transition form factor in a nonlocal chiral quark model Type Journal Article
Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 89 Issue 5 Pages (down) 054031 - 14pp
Keywords
Abstract We study the pion distribution amplitude (pi DA) in the context of a nonlocal chiral quark model. The corresponding Lagrangian reproduces the phenomenological values of the pion mass and decay constant, as well as the momentum dependence of the quark propagator obtained in lattice calculations. It is found that the obtained pi DA has two symmetric maxima, which arise from the new contributions generated by the nonlocal character of the interactions. This pi DA is applied to leading order and next-to-leading order calculations of the pion-photon transition form factor. Implications of the results are discussed.
Address [Gomez Dumm, D.] Univ Nacl La Plata, CONICET, IFLP, Dept Fis, RA-1900 La Plata, Argentina
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000334304700006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1775
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Author Coppola, M.; Gomez Dumm, D.; Noguera, S.; Scoccola, N.N.
Title Pion-to-vacuum vector and axial vector amplitudes and weak decays of pions in a magnetic field Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 99 Issue 5 Pages (down) 054031 - 18pp
Keywords
Abstract We propose a model-independent parametrization for the one-pion-to-vacuum matrix elements of the vector and axial vector hadronic currents in the presence of an external uniform magnetic field. It is shown that, in general, these hadronic matrix elements can be written in terms of several gauge covariant Lorentz structures and form factors. Within this framework we obtain a general expression for the weak decay pi(- )-> l(nu)over bar(l) and discuss the corresponding limits of strong and weak external magnetic fields.
Address [Coppola, M.; Scoccola, N. N.] Consejo Nacl Invest Cient & Tecn, Rivadavia 1917, RA-1033 Buenos Aires, DF, Argentina
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000462915500003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3962
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Author Coppola, M.; Gomez Dumm, D.; Noguera, S.; Scoccola, N.N.
Title Neutral and charged pion properties under strong magnetic fields in the NJL model Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 100 Issue 5 Pages (down) 054014 - 17pp
Keywords
Abstract In the framework of the Nambu-Jona-Lasino (NJL) model, we study the effect of an intense external uniform magnetic field on neutral and charged pion masses and decay form factors. In particular, the treatment of charged pions is carried out on the basis of the Ritus eigenfunction approach to magnetized relativistic systems. Our analysis shows that in the presence of the magnetic field three and four nonvanishing pion-to-vacuum hadronic form factors can be obtained for the case of the neutral and charged pions, respectively. As expected, it is seen that for nonzero magnetic field the pi(0) meson can still be treated as a pseudo Nambu-Goldstone boson, and consequently the corresponding form factors are shown to satisfy various chiral relations. For definite parametrizations of the model, numerical results for pi(0) and pi(+/-) masses and decay constants are obtained and compared with previous calculations given in the literature.
Address [Coppola, M.; Scoccola, N. N.] Consejo Nacl Invest Cient & Tecn, Rivadavia 1917, RA-1033 Buenos Aires, DF, Argentina
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000486642100003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4148
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Author Coppola, M.; Gomez Dumm, D.; Noguera, S.; Scoccola, N.N.
Title Masses of magnetized pseudoscalar and vector mesons in an extended NJL model: The role of axial vector mesons Type Journal Article
Year 2024 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 109 Issue 5 Pages (down) 054014 - 30pp
Keywords
Abstract We study the mass spectrum of light pseudoscalar and vector mesons in the presence of an external uniform magnetic field B., considering the effects of the mixing with the axial-vector meson sector. The analysis is performed within a two-flavor NJL-like model which includes isoscalar and isovector couplings together with a flavor mixing 't Hooft-like term. The effect of the magnetic field on charged particles is taken into account by retaining the Schwinger phases carried by quark propagators, and expanding the corresponding meson fields in proper Ritus-like bases. The spin-isospin and spin-flavor decomposition of meson mass states is also analyzed. For neutral pion masses it is shown that the mixing with axial vector mesons improves previous theoretical results, leading to a monotonic decreasing behavior with B that is in good qualitative agreement with lattice QCD (LQCD) calculations, both for the case of constant or B-dependent couplings. Regarding charged pions, it is seen that the mixing softens the enhancement of their mass with B. As a consequence, the energy becomes lower than the one corresponding to a pointlike pion, improving the agreement with LQCD results. The agreement is also improved for the magnetic behavior of the lowest.thorn energy state, which does not vanish for the considered range of values of B-a fact that can be relevant in connection with the occurrence of meson condensation for strong magnetic fields.
Address [Coppola, M.; Scoccola, N. N.] Comis Nacl Energia Atom, Dept Fis, Ave Libertador 8250, RA-1429 Buenos Aires, Argentina
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:001196327000010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6119
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Author Gomez Dumm, D.; Noguera, S.; Scoccola, N.N.
Title eta-gamma and eta(')-gamma transition form factors in a nonlocal NJL model Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 95 Issue 5 Pages (down) 054006 - 19pp
Keywords
Abstract We study the eta and eta(') distribution amplitudes (DAs) in the context of a nonlocal SU(3)(L) circle times SUd(3)(R) chiral quark model. The corresponding Lagrangian allows us to reproduce the phenomenological values of pseudoscalar meson masses and decay constants, as well as the momentum dependence of the quark propagator arising from lattice calculations. It is found that the obtained DAs have two symmetric maxima, which arise from new contributions generated by the nonlocal character of the interactions. These DAs are then applied to the calculation of the eta-gamma and eta(')-gamma transition form factors. Implications of our results regarding higher twist corrections and/or contributions to the transition form factors originated by gluon-gluon components in the eta and eta(') mesons are discussed.
Address [Gomez Dumm, D.] Univ Nacl La Plata, Fac Ciencias Exactas, Dept Fis, IFLP,CONICET, CC 67, RA-1900 La Plata, Buenos Aires, Argentina
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000396030600002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3031
Permanent link to this record