particle

symbol

antipart.

composition

mass (MeV/c²)

I^G

J^PC

S

C

B

lifetime(s)

main decay

ch-kaon

$K^{+}$

$K^{-}$

$u\overline{s}$

439.677 ± 0.016

1/2

0⁻

1

0

0

1.2380 ± 0.0021 × 10⁻⁸

${\mu }^{+}+{\nu }_{\mu }$

${\pi }^{+}+{\pi }^0$

${\pi }^{+}+{\pi }^{+}+{\pi }^{-}$

${\pi }^0+e^{+}+{\nu }_e$

n-kaon

$K^0$

${\overline{K}}^0$

$d\overline{s}$

497.611 ± 0.013

1/2

0⁻

1

0

0

kaon-S

$K_S^0$

$K_S^0$

$\left(d\overline{s}-s\overline{d}\right)/\sqrt{2}$

497.611 ± 0.013

1/2

0⁻

0

0

8.954 ± 0.004 × 10⁻¹¹

${\pi }^{+}+{\pi }^{-}$

${\pi }^0+{\pi }^0$

kaon-L

$K_L^0$

$K_L^0$

$\left(d\overline{s}+s\overline{d}\right)/\sqrt{2}$

497.611 ± 0.013

1/2

0⁻

0

0

5.116 ± 0.021 × 10⁻⁸

${\pi }^{\pm }+e^{\mp }+{\nu }_e$

${\pi }^{\pm }+{\mu }^{\mp }+{\nu }_{\mu }$

${\pi }^0+{\pi }^0+{\pi }^0$

${\pi }^{+}+{\pi }^0+{\pi }^{-}$