Puzzle in the Charmed $D_s$ meson decays into pions: Could the light quarks be not so light?

Hoang Ngoc Long, Nguyen Ai Viet, Pham Xuan Yem

The inclusive decay rate into pions of the charmed $D_s$ meson is surprisingly larger than estimates expected from the $W$ annihilation, adopting commonly used values of current-al…