Search for a New Particle $X$($\to b\bar{b}$) Production in Association with a $W^{\pm}$ Boson at the Tevatron

We present an updated search for a new particle that decays into $b\bar{b}$ and is produced in association with $W^{\pm}$ boson in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV. The search uses a Run II dataset accumulated by the CDF experiment at the Fermilab corresponding to an integrated luminosity of about $300$ pb$^{-1}$. We select events with an electron or muon, large missing transverse energy, and two jets, with at least one of the jets $b$-tagged. We present results as a function of new particle mass. In particular, we place upper limits on the cross section of $W^\pm h \to W^\pm b\bar{b}$ and $\rho_{TC} \to W^\pm \pi_{TC} \to W^\pm b\bar{b}$ production.