= Kalman Vertex Fitter =

The standard Kalman Vertex Fitter. 

Kalman Filter. R. Fruehwirth, R. Kubinec, W. Mitaroff and M. Regler, Comp. Phys. Comm. 96, 189 (1996)

Track model is a helix. Linearizes tracks around the "fsmw" mode. What else is there worth knowing about?
Takes no extra input parameters.

See also:

 * WW's thesis: CMS TS-2006/012 W. Waltenberger, Development of Vertex Finding and Vertex Fitting Algorithms for CMS http://wwwhephy.oeaw.ac.at/u3w/w/walten/www/diss_v2.pdf
 * http://cmsdoc.cern.ch/doc/notes/docs/NOTE2006_032