$\Delta \mathit C$ = 1 WEAK NEUTRAL CURRENT FORBIDDEN
Allowed by higher-order electroweak interactions.
$\Gamma\mathrm {( {{\mathit D}^{+}} \rightarrow {{\mathit \rho}^{+}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<5.6\times 10^{-4}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{+}} \rightarrow {{\mathit \pi}^{+}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<6.7\times 10^{-8}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{+}} \rightarrow {{\mathit \pi}^{+}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<1.1\times 10^{-6}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit K}^{-}} {{\mathit K}^{+}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $(1.54\pm{0.32})\times 10^{-7}$
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit K}^{-}} {{\mathit K}^{+}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<1.1\times 10^{-5}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit K}^{-}} {{\mathit \pi}^{+}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<3.59\times 10^{-4}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \pi}^{+}} {{\mathit \pi}^{-}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $(9.6\pm{1.2})\times 10^{-7}$
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \pi}^{+}} {{\mathit \pi}^{-}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<7\times 10^{-6}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \phi}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<3.1\times 10^{-5}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \phi}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<5.2\times 10^{-5}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \omega}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<8.3\times 10^{-4}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \omega}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<6\times 10^{-6}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \eta}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<5.3\times 10^{-4}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \eta}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<3\times 10^{-6}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \pi}^{0}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<4\times 10^{-6}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \pi}^{+}} {{\mathit \pi}^{-}} {{\mathit \pi}^{0}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<8.1\times 10^{-4}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \pi}^{0}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<1.8\times 10^{-4}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \rho}^{0}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<2.2\times 10^{-5}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \rho}^{0}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<1.0\times 10^{-4}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \gamma}} {{\mathit \gamma}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<8.5\times 10^{-7}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<7.9\times 10^{-8}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}^{0}} \rightarrow {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<6.2\times 10^{-9}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}_{{s}}^{+}} \rightarrow {{\mathit K}^{+}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<3.7\times 10^{-6}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}_{{s}}^{+}} \rightarrow {{\mathit K}^{*}{(892)}^{+}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<1.4\times 10^{-3}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit D}_{{s}}^{+}} \rightarrow {{\mathit K}^{+}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<1.4\times 10^{-7}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit \Lambda}_{{c}}^{+}} \rightarrow {{\mathit p}} {{\mathit e}^{+}} {{\mathit e}^{-}} )}$ $/$ $\Gamma\mathrm {(total)}$ $<5.5\times 10^{-6}$ CL=90.0%
$\Gamma\mathrm {( {{\mathit \Lambda}_{{c}}^{+}} \rightarrow {{\mathit p}} {{\mathit \mu}^{+}} {{\mathit \mu}^{-}} non-resonant)}$ $/$ $\Gamma\mathrm {(total)}$ $<7.7\times 10^{-8}$ CL=90.0%