Timelike behavior of the pion electromagnetic form factor in the functional formalism

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389005%3A_____%2F22%3A00563399" target="_blank" >RIV/61389005:_____/22:00563399 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1103/PhysRevD.106.034030" target="_blank" >https://doi.org/10.1103/PhysRevD.106.034030</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevD.106.034030" target="_blank" >10.1103/PhysRevD.106.034030</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Timelike behavior of the pion electromagnetic form factor in the functional formalism

Popis výsledku v původním jazyce

The electromagnetic form factor of the pion is calculated within the use of functional formalism. We develop integral representation for the minimal set of Standard Model Green's functions and derive the dispersion relation for the form factor in the two-flavor QCD isospin limit m(u) = m(d). We use the dressed quark propagator as obtained from the gap equation in Minkowski space and within the Dyson-Schwinger equations formalism to derive the approximate dispersion relation for the form factor for the first time. We evaluate the form factor for the spacelike as well as for the timelike momentum in the presented formalism. A new Nakanishi-like form of integral representation is proved on the basis of the vector BetheSalpeter equation for the quark-photon vector with a ladder-rainbow kernel. The gauge technique turns out to be a part of the entire structure of the vertex. In the analytic approach presented here, it is shown that a large amount of the p-meson peak in the cross section e(+) e(-) -> pi(+) pi(-) is governed by the gauge invariance of QED/QCD-i.e., by a gauge-technique-constructed quark-photon vertex. This approximation naturally explains the broad shape of the rho-meson peak.

Název v anglickém jazyce

Timelike behavior of the pion electromagnetic form factor in the functional formalism

Popis výsledku anglicky

The electromagnetic form factor of the pion is calculated within the use of functional formalism. We develop integral representation for the minimal set of Standard Model Green's functions and derive the dispersion relation for the form factor in the two-flavor QCD isospin limit m(u) = m(d). We use the dressed quark propagator as obtained from the gap equation in Minkowski space and within the Dyson-Schwinger equations formalism to derive the approximate dispersion relation for the form factor for the first time. We evaluate the form factor for the spacelike as well as for the timelike momentum in the presented formalism. A new Nakanishi-like form of integral representation is proved on the basis of the vector BetheSalpeter equation for the quark-photon vector with a ladder-rainbow kernel. The gauge technique turns out to be a part of the entire structure of the vertex. In the analytic approach presented here, it is shown that a large amount of the p-meson peak in the cross section e(+) e(-) -> pi(+) pi(-) is governed by the gauge invariance of QED/QCD-i.e., by a gauge-technique-constructed quark-photon vertex. This approximation naturally explains the broad shape of the rho-meson peak.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10303 - Particles and field physics

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2022

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Physical Review D

ISSN

2470-0010

e-ISSN

2470-0029

Svazek periodika

106

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

21

Strana od-do

034030

Kód UT WoS článku

000872136400005

EID výsledku v databázi Scopus

2-s2.0-85136929398