B ? J/? KS Reconstruction
- J/? ? ? +? - require two central tracks with pT > 1.5 GeV/c
- KS ? ? +? - use long lifetime to reject background: Lxy/? > 5
- Perform 4-track fit assuming B? J/? KS
- constrain ? ? and ?-? to mass of KS and J/? respectively
- force KS to point to B vertex and B to point to primary