  Within the framework QCD sum rules, we use the least square fitting method to
investigate the first radial excitations of the nucleon and light mesons such
as $\rho$, $K^{*}$, $\pi$ , $\varphi$. The extracted masses of these radial
excitations are consistent with the experimental data. Especially we find that
the decay constant of $\pi(1300)$, which is the the first radial excitation of
$\pi$, is tiny and strongly suppressed as a consequence of chiral symmetry.

High Energy Physics - Phenomenology