D meson

D−: dcD0: cuD0: ucD+s: csThe D mesons are the lightest particle containing charm quarks. They are often studied to gain knowledge on the weak interaction. The strange D mesons (Ds) were called the 'F mesons' prior to 1986.(>5% of decays) The D mesons are the lightest particle containing charm quarks. They are often studied to gain knowledge on the weak interaction. The strange D mesons (Ds) were called the 'F mesons' prior to 1986. The D mesons were discovered in 1976 by the Mark I detector at the Stanford Linear Accelerator Center. Since the D mesons are the lightest mesons containing a single charm quark (or antiquark), they must change the charm (anti)quark into an (anti)quark of another type to decay. Such transitions involve a change of the internal charm quantum number, and can take place only via the weak interaction. In D mesons, the charm quark preferentially changes into a strange quark via an exchange of a W particle, therefore the D meson preferentially decays into Ks and πs. ^ PDG reports the resonance width (Γ). Here the conversion τ = ħ/Γ is given instead.