FTC is the dedicated fitter for low energy muons, from 200 MeV up to 4-5 GeV. At these energies most of the muons stop inside SNO. The fitter uses the ring like pattern that these muons produce in order to reconstruct their direction. Continuous timing information along the muon track is used to reconstruct the entrance vertex and improve the direction fit. Note that FTC never fails but may return bad fits. Also, FTC does not provide identification of stopping vs through-going muons. Selection of stopping muons must be defined independently.
More generally this algorithm can be applied to the reconstruction of any heavy charged particle track (muon, pion, kaon, ...).
FTC is a new tool whose frame of application is still being studied. Corresponding detailed documentation can be found on Manhattan.
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