meson mass

calculated mass

meson

spin

$M_m$

k

$m_{calc}$

$\frac{m_{calc}-M_m}{M_m}$

π

0

$273.13m_e$

1

$274.1m_e$

$3.5\times {10}^{-3}$

μ

$\hslash /2$

$206.77m_e$

4

$205.6m_e$

$-5.8\times {10}^{-3}$