Measuring the CP Violating Phase in Bs Mixing Using Bs -> J/\psi f_0(980)

Understand

We show that the decay Bs -> J/psi f0(980), f0(980)->pi+ pi- can be used to measure the CP violating phase in Bs mixing, -2\beta_s, and estimate the sensitivity as +/- 0.050 rad, for 2/fb of LHCb data.

• After adding in the related Bs -> J/psi eta', \eta' -> rho gamma mode, the sensitivity improves to +/- 0.044 rad.
• Use of these CP eigenstates obviates the need for a transversity analysis that must be used in the case of Bs -> J/psi phi decays.