Long-Lived Heavy Quarks: A Review

Table 6

Meson-to-Meson and Meson-to-Baryon processes for 𝑄𝑢 and 𝑄𝑑 mesonic states, where 𝑄=𝑋_5/3,𝑇_2/3,𝐵_−1/3,𝑌_−4/3 and 𝑞=𝑢,𝑑. Similar transitions can be obtained for the charge conjugated processes involving 𝑄𝑞. Assuming that the cross-sections for all the transitions are of the same order of magnitude, Meson-to-Baryon processes to 𝑄𝑢𝑑 states are more likely than those involving 𝑄𝑢𝑢 and 𝑄𝑑𝑑 in the final state.

(a)  

Meson-to-Meson 2→2 processes
Charge exchange
𝑄𝑢+𝑝↔𝑄𝑑+𝑛
Elastic scattering
𝑄𝑞+𝑝/𝑛→𝑄𝑞+𝑝/𝑛

(b)  

Meson-to-Baryon 2→2 processes
Baryon exchange
𝑄𝑢+𝑛→𝑄𝑢𝑑+𝜋^−
𝑄𝑢+𝑛→𝑄𝑑𝑑+𝜋^0
𝑄𝑢+𝑝→𝑄𝑢𝑢+𝜋^−
𝑄𝑢+𝑝→𝑄𝑢𝑑+𝜋^0
𝑄𝑑+𝑛→𝑄𝑢𝑑+𝜋^0
𝑄𝑑+𝑛→𝑄𝑑𝑑+𝜋^+
𝑄𝑑+𝑝→𝑄𝑢𝑢+𝜋^0
𝑄𝑑+𝑝→𝑄𝑢𝑑+𝜋^+

(c)  

Meson-to-Meson 2→3 processes
Inelastic scattering
𝑄𝑢+𝑛→𝑄𝑑+𝑛+𝜋^−
𝑄𝑢+𝑛→𝑄𝑢+𝑛+𝜋^0
𝑄𝑢+𝑛→𝑄𝑢+𝑝+𝜋^−
𝑄𝑢+𝑝→𝑄𝑑+𝑝+𝜋^−
𝑄𝑢+𝑝→𝑄𝑢+𝑝+𝜋^0
𝑄𝑢+𝑝→𝑄𝑢+𝑛+𝜋^+
𝑄𝑢+𝑝→𝑄𝑑+𝑛+𝜋^0
𝑄𝑑+𝑛→𝑄𝑢+𝑛+𝜋^+
𝑄𝑑+𝑛→𝑄𝑑+𝑛+𝜋^0
𝑄𝑑+𝑛→𝑄𝑢+𝑝+𝜋^0
𝑄𝑑+𝑛→𝑄𝑑+𝑝+𝜋^−
𝑄𝑑+𝑝→𝑄𝑢+𝑝+𝜋^+
𝑄𝑑+𝑝→𝑄𝑑+𝑝+𝜋^0
𝑄𝑑+𝑝→𝑄𝑑+𝑛+𝜋^+

(d)  

Meson-to-Baryon 2→3 processes
Baryon exchange
𝑄𝑢+𝑛→𝑄𝑢𝑑+𝜋^−+𝜋^0
𝑄𝑢+𝑛→𝑄𝑑𝑑+𝜋^−+𝜋^+
𝑄𝑢+𝑛→𝑄𝑑𝑑+𝜋^0+𝜋^0
𝑄𝑢+𝑝→𝑄𝑢𝑢+𝜋^−+𝜋^0
𝑄𝑢+𝑝→𝑄𝑢𝑑+𝜋^−+𝜋^+
𝑄𝑢+𝑝→𝑄𝑢𝑑+𝜋^0+𝜋^0
𝑄𝑢+𝑝→𝑄𝑑𝑑+𝜋^++𝜋^0
𝑄𝑑+𝑛→𝑄𝑢𝑑+𝜋^−+𝜋^+
𝑄𝑑+𝑛→𝑄𝑢𝑑+𝜋^0+𝜋^0
𝑄𝑑+𝑛→𝑄𝑑𝑑+𝜋^0+𝜋^+
𝑄𝑑+𝑝→𝑄𝑢𝑢+𝜋^−+𝜋^+
𝑄𝑑+𝑝→𝑄𝑢𝑢+𝜋^0+𝜋^0
𝑄𝑑+𝑝→𝑄𝑢𝑑+𝜋^0+𝜋^+