Constraining four generation SM with b\to s \gamma and b\to s g decays
  Using the experimental result on b\to s\gamma and theoretical result on b\to sg, a four -generation SM is analysed to constrain the rephasing-invariant combinations of the CKM matrix and masses of the fourth generation quarks. 
T. M. Aliev, D. A. Demir, N. K. Pak