Searching for a light top squark at the Fermilab Tevatron

We describe a method to help the search for a light top squark $({\tilde{M}}_t+{\tilde{M}}_{\mathrm{LSP}}<m_t)$ at the Fermilab Tevatron. Traditional search methods rely upon a series of stringent background-reducing cuts which, unfortunately, leave very few signal events given the present data set. To avoid this difficulty, we instead suggest using a milder set of cuts, combined with a “superweight,” whose purpose is to discriminate between signal and background events. The superweight consists of a sum of terms, each of which are either zero or one. The terms are assigned event-by-event depending upon the values of various observables. We suggest a method for choosing the observables as well as the criteria used to assign the values such that the superweight is “large” for the supersymmetric signal and “small” for the standard model background. For illustration, we mainly consider the detection of tops squarks coming from top quark decay, making our analysis especially relevant to the $W+2\mathrm{}$ jets top quark sample.