pdgLive

$\Delta \mathit S$ = 1 WEAK NEUTRAL CURRENT FORBIDDEN
Allowed by higher-order electroweak interactions.

$\Gamma\mathrm {( {{\mathit K}^{+}} \rightarrow {{\mathit \pi}^{+}} {{\mathit \pi}^{0}} {{\mathit \nu}} {{\overline{\mathit \nu}}} )}$ $/$ $\Gamma\mathrm {(total)}$

$<4.3\times 10^{-5}$ CL=90.0%

$\Gamma\mathrm {( {{\mathit K}^{+}} \rightarrow {{\mathit \pi}^{+}} {{\mathit \nu}} {{\overline{\mathit \nu}}} )}$ $/$ $\Gamma\mathrm {(total)}$

$(1.14^{+0.40}_{-0.33})\times 10^{-10}$

$\Gamma\mathrm {( {{\mathit K}^{+}} \rightarrow {{\mathit \pi}^{+}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$(9.17\pm{0.14})\times 10^{-8}$ (S = 1.8)

$\Gamma\mathrm {( {{\mathit K}^{+}} \rightarrow {{\mathit \pi}^{+}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$(3.00\pm{0.09})\times 10^{-7}$

$\Gamma\mathrm {( {{\mathit K}_S^0} \rightarrow {{\mathit \pi}^{0}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$(2.9^{+1.5}_{-1.2})\times 10^{-9}$

$\Gamma\mathrm {( {{\mathit K}_S^0} \rightarrow {{\mathit \pi}^{0}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$(3.0^{+1.5}_{-1.2})\times 10^{-9}$

$\Gamma\mathrm {( {{\mathit K}_S^0} \rightarrow {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$<9\times 10^{-9}$ CL=90.0%

$\Gamma\mathrm {( {{\mathit K}_S^0} \rightarrow {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$<2.1\times 10^{-10}$ CL=90.0%

$\Gamma\mathrm {( {{\mathit K}_L^0} \rightarrow {{\mathit \pi}^{0}} {{\mathit \pi}^{0}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$<9.2\times 10^{-11}$ CL=90.0%

$\Gamma\mathrm {( {{\mathit K}_L^0} \rightarrow {{\mathit \pi}^{0}} {{\mathit \pi}^{0}} {{\mathit \nu}} {{\overline{\mathit \nu}}} )}$ $/$ $\Gamma\mathrm {(total)}$

$<8.1\times 10^{-7}$ CL=90.0%

$\Gamma\mathrm {( {{\mathit K}_L^0} \rightarrow {{\mathit \pi}^{0}} {{\mathit \pi}^{0}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$<6.6\times 10^{-9}$ CL=90.0%

$\Gamma\mathrm {( {{\mathit K}_L^0} \rightarrow {{\mathit \pi}^{0}} {{\mathit \nu}} {{\overline{\mathit \nu}}} )}$ $/$ $\Gamma\mathrm {(total)}$

$<3.0\times 10^{-9}$ CL=90.0%

$\Gamma\mathrm {( {{\mathit K}_L^0} \rightarrow {{\mathit e}^{+}} {{\mathit e}^{-}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$(3.56\pm{0.21})\times 10^{-8}$

$\Gamma\mathrm {( {{\mathit K}_L^0} \rightarrow {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$(2.69\pm{0.27})\times 10^{-9}$

$\Gamma\mathrm {( {{\mathit K}_L^0} \rightarrow {{\mathit \pi}^{0}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$<2.8\times 10^{-10}$ CL=90.0%

$\Gamma\mathrm {( {{\mathit K}_L^0} \rightarrow {{\mathit \pi}^{+}} {{\mathit \pi}^{-}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$(3.11\pm{0.19})\times 10^{-7}$

$\Gamma\mathrm {( {{\mathit K}_L^0} \rightarrow {{\mathit \pi}^{0}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$<3.8\times 10^{-10}$ CL=90.0%

$\Gamma\mathrm {( {{\mathit K}_L^0} \rightarrow {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$(9^{+6}_{-4})\times 10^{-12}$

$\Gamma\mathrm {( {{\mathit K}_L^0} \rightarrow {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$(6.84\pm{0.11})\times 10^{-9}$

$\Gamma\mathrm {( {{\mathit \Sigma}^{+}} \rightarrow {{\mathit p}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$(2.4^{+1.7}_{-1.3})\times 10^{-8}$

$\Gamma\mathrm {( {{\mathit \Sigma}^{+}} \rightarrow {{\mathit p}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$

$<7\times 10^{-6}$

[1]	See the Particle Listings below for the energy limits used in this measurement.

[2]	Violates $\mathit CP$ in leading order. Test of direct $\mathit CP$ violation since the indirect $\mathit CP$-violating and $\mathit CP$-conserving contributions are expected to be suppressed.

[3]	Allowed by higher-order electroweak interactions.

[4]	See the Particle Listings below for the energy limits used in this measurement.

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