Least squares fit of bubble chamber tracks taking into account multiple scattering

Presents a new approach to the problem of taking into account multiple scattering when making the least squares fit of bubble chamber tracks to film measurements. For completeness, the more refined version of the standard fit which has been developed for the new large hydrogen bubble chambers, is also described. In the standard fit, energy loss and inhomogeneity of magnetic field only are taken into account, and five parameters are fitted. In the new method, the scattered track is followed more closely by introducing additional parameters each with known mean and variance. The amount of additional computation depends directly on the total multiple scattering deviation expected. The method is particularly useful for connecting tracks as the parameters at the two vertices are fitted simultaneously. (10 refs).