Observation of the semileptonic decays $D^0\rightarrow K_S^0\pi^-\pi^0
e^+ \nu_e$ and $D^+\rightarrow K_S^0\pi^+\pi^- e^+ \nu_e$
Observation of the semileptonic decays $D^0\rightarrow K_S^0\pi^-\pi^0
e^+ \nu_e$ and $D^+\rightarrow K_S^0\pi^+\pi^- e^+ \nu_e$
By analyzing $e^+e^-$ annihilation data corresponding to an integrated luminosity of 2.93 $\rm fb^{-1}$ collected at a center-of-mass energy of 3.773 GeV with the \text{BESIII} detector, the first observation of the semileptonic decays $D^0\rightarrow K_S^0\pi^-\pi^0 e^+ \nu_e$ and $D^+\rightarrow K_S^0\pi^+\pi^- e^+ \nu_e$ is reported. With a dominant hadronic contribution from …