de Melo, J. P. B. C.
Número total de Autores: 4
Afiliação do(s) autor(es):
 Kyungpook Natl Univ, Dept Phys, Teachers Coll, Daegu 41566 - South Korea
 Inst Tecnol Aeronaut, BR-12228900 Sao Jose Dos Campos, SP - Brazil
 North Carolina State Univ, Dept Phys, Raleigh, NC 27695 - USA
 Univ Cidade Sao Paulo, Univ Cruzeiro Sul, Lab Fis Teor & Computac, BR-01506000 Sao Paulo, SP - Brazil
Número total de Afiliações: 4
Tipo de documento:
Physical Review D;
DEC 23 2019.
Citações Web of Science:
We investigate the pion electromagnetic half-off-shell form factors, which parametrize the matrix element of the charged pion electromagnetic current with one leg off mass shell and the other leg on mass shell, using an exactly solvable manifestly covariant model of a (3 + 1)- dimensional fermion field theory. The model provides a three-dimensional imaging of the two off-shell pion form factors F-1 and F-2 as a function of (Q(2), t), which are related to each other, satisfying the Ward-Takahashi identity. The normalization of the renormalized charge form factor F-1 is fixed by F-1 (Q(2) = 0, t = m(pi)(2)) = 1, while the other form factor F-2 vanishes; i.e., F-2 (Q(2), t = = 0 for any value of Q(2) due to the time-reversal invariance of the strong interaction. We define the new form factor g(Q(2), t) = F-2 (Q(2), t)/(t - m(pi)(2)) and find that g(Q(2), t) can be measurable in the on-mass-shell limit. In particular, g(Q(2) = 0, t = m(pi)(2)) is related with the pion charge radius. We also compare our form factors with the data extracted from the pion clectroproduction reaction for both the off-shell region (t < 0) and the on-shell limit (t -> m(pi)(2)). (AU)