| Records |
| Author |
Noguera, S.; Vento, V. |
| Title |
The pion transition form factor and the pion distribution amplitude |
Type |
Journal Article |
| Year |
2010 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
| Volume |
46 |
Issue |
2 |
Pages |
197-205 |
| Keywords |
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| Abstract |
Recent BaBar data on the pion transition form factor, whose Q(2)-dependence is much steeper then predicted by asymptotic Quantum Chromodynamics (QCD), have caused a renewed interest in its theoretical description. We present here a formalism based on a model-independent description for low photon virtuality and a high photon virtuality description based on QCD, which match at a scale Q(0). The high photon virtuality description incorporates a flat pion distribution amplitude, phi(x) = 1, at the matching scale Q(0) and QCD evolution from Q(0) to Q > Q(0). The flat pion distribution is connected, through soft pion theorems and chiral symmetry, to the pion valence parton distribution at the same low scale Q(0). The procedure leads to a good description of the data, and by incorporating additional twist-three effects, to an excellent description of the data. |
| Address |
[Noguera, S.] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Valencia, Spain, Email: Santiago.Noguera@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 |
1434-6001 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
ISI:000284869600005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ elepoucu @ |
Serial |
312 |
| Permanent link to this record |
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| Author |
Gomez Dumm, D.; Noguera, S.; Scoccola, N.N. |
| Title |
Pion radiative weak decays in nonlocal chiral quark models |
Type |
Journal Article |
| Year |
2011 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
698 |
Issue |
3 |
Pages |
236-242 |
| Keywords |
Nonlocal quark models; Pion radiative weak decays |
| Abstract |
We analyze the radiative pion decay pi(+) -> e(+) nu(e)gamma within nonlocal chiral quark models that include wave function renormalization. In this framework we calculate the vector and axial-vector form factors F-V and F-A at q(2) = 0 – where q(2) is the e(+) nu(e) squared invariant mass – and the slope a of F-V (q(2)) at q(2) -> 0. The calculations are carried out considering different nonlocal form factors, in particular those taken from lattice QCD evaluations, showing a reasonable agreement with the corresponding experimental data. The comparison of our results with those obtained in the (local) NJL model and the relation of F-V and a with the form factor in pi(0) -> gamma*gamma decays are discussed. |
| Address |
[Gomez Dumm, D.] Univ Nacl La Plata, CONICET, Dept Fis, IFLP, RA-1900 La Plata, Buenos Aires, Argentina, Email: dumm@fisica.unlp.edu.ar |
| 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:000289543700008 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
609 |
| Permanent link to this record |
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| |
| Author |
Noguera, S.; Scopetta, S. |
| Title |
Eta-photon transition form factor |
Type |
Journal Article |
| Year |
2012 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
85 |
Issue |
5 |
Pages |
054004 - 12pp |
| Keywords |
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| Abstract |
The eta-photon transition form factor is evaluated in a formalism based on a phenomenological description at low values of the photon virtuality, and a QCD-based description at high photon virtualities, matching at a scale Q(0)(2). The high photon virtuality description makes use of a distribution amplitude calculated in the Nambu-Jona-Lasinio model with Pauli-Villars regularization at the matching scale Q(0)(2), and QCD evolution from Q(0)(2) to higher values of Q(2). A good description of the available data is obtained. The analysis indicates that the recent data from the BABAR collaboration on pion and eta transition form factor can be well reproduced, if a small contribution of higher twist is added to the dominant twist-two contribution at the matching scale Q(0)(2). |
| Address |
[Noguera, S.] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: Santiago.Noguera@uv.es |
| 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 |
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:000300972300001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
924 |
| Permanent link to this record |
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| |
| Author |
Gomez Dumm, D.; Noguera, S.; Scoccola, N.N. |
| Title |
Form factors of radiative pion decays in nonlocal chiral quark models |
Type |
Journal Article |
| Year |
2012 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
86 |
Issue |
7 |
Pages |
074020 - 10pp |
| Keywords |
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| Abstract |
We study the radiative pion decay pi(+) -> e(+) nu(e)gamma within nonlocal chiral quark models that include wave function renormalization. In this framework we analyze the momentum dependence of the vector form factor F-V(q(2)) and the slope of the axial-vector form factor F-A(q(2)) at threshold. Our results are compared with available experimental information and with the predictions given by the Nambu-Jona-Lasinio model. In addition we calculate the low energy constants l(5) and l(6), comparing our results with the values obtained in chiral perturbation theory. |
| Address |
[Gomez Dumm, D.] Univ Nacl La Plata, CONICET, IFLP, Dept Fis, RA-1900 La Plata, Argentina |
| 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 |
1550-7998 |
ISBN |
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Medium |
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| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000309731200001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1183 |
| Permanent link to this record |
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| Author |
Noguera, S.; Vento, V. |
| Title |
Model analysis of the world data on the pion transition form factor |
Type |
Journal Article |
| Year |
2012 |
Publication |
European Physical Journal A |
Abbreviated Journal |
Eur. Phys. J. A |
| Volume |
48 |
Issue |
10 |
Pages |
143 - 4pp |
| Keywords |
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| Abstract |
We discuss the impact of recent Belle data on our description of the pion transition form factor based on the assumption that a perturbative formalism and a nonperturbative one can be matched in a physically acceptable manner at a certain hadronic scale Q(0). We discuss the implications of the different parameters of the model in comparing with world data and conclude that within experimental errors our description remains valid. Thus we can assert that the low Q(2) nonperturbative description together with an additional 1/Q(2) term at the matching scale have a strong influence on the Q(2) behavior up to very high values of Q(2). |
| Address |
[Noguera, S.] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot Valencia, Spain, Email: Santiago.Noguera@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 |
1434-6001 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000310630100008 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
1198 |
| Permanent link to this record |
