7 papers
Dispersion Relations and Sum Rules for the pi ->gamma gamma* and gamma* ->gamma pi form factor
Tran N. Truong
Sum rules for the off-shell isovector form factor pi -> gamma gamma* are given in terms of the pion form factor and the gamma pi ->pi pi experimental data. Similarly the correspond…
Remarks on the Calculation of the Enhancement Factor in the K -> 2 pion Decay
Tran N. Truong
The problem of calculation of the enhancement factor due to the strong pion final state interaction is reexamined in the light of recent interest in understanding of the origine of…
When is it possible to use perturbation technique in field theory ?
Tran N. Truong
The vector pion form factor is used as an example to analyze this question. Given the experimental radius of the pion, the crucial question is whether perturbative methods could be…
Dispersion Relation Analyses of Pion Form Factor, Chiral Perturbation Theory and Unitarized Calculations
Tran N. Truong
The Vector Pion form factor below 1 GeV is analyzed using experimental data on its modulus, the P-wave pion pion phase shifts and dispersion relation. It is found that causality is…
Study of Gamma + Pi --> Pi + Pi
Tran N. Truong
The problem of Gamma + Pi --> Pi + Pi is studied using the axial anomaly, elastic unitarity, analyticity and crossing symmetry. Single variable dispersion relation is assumed. Usin…
Taylor's Series and Dispersion Relation Analyses of the Vector Pion Form Factor and their Comparison with Perturbative and Non Perturbative Calculations
Tran N. Truong
The first three coefficients of the Taylor's series expansion of the vector pion form factor as a function of the momentum transfer are evaluated using experimental data on the pio…