Searching for $t\to cg$ at the Fermilab Tevatron

Abstract

We examine the experimental observability of the decay mode $t\to cg$ at the Fermilab Tevatron via the flavor-changing neutral current vertex $t\bar{c}g$. We find that with the existing data, one should be able to probe the $t\bar{c}g$ coupling to a value smaller than indirect limits previously obtained from $b\to s{\hat{I}}^3$ and the measured branching fraction for $t\to bW$, reaching $BF(t\to cg)\sim$ 15\% - 28\%. A data sample of 1~fb${}^{-1}$ (10~fb${}^{-1}$) at $\sqrt{s}=2$~TeV may probe the $t\to cg$ branching fraction to a level of 2\% (0.5\%).

12 pages, 2 figures, RevTeX, postscript files available via anonymous ftp at ftp://ucdhep.ucdavis.edu/han/top/tcgluon.ps, and fig#.ps