Search for New Physics in ZZ+MET

Jared Vasquez, Daniel Whiteson
University of California, Irvine

Bo Jayatilaka
Duke University

We present a search for a heavy unstable fourth generation neutrino $N_2$ which decays to a heavy stable fourth generation neutrino $N_1$ and a $Z$ boson. Pair production of $N_2$ via the process $p\bar{p} \rightarrow N_2N_2 \rightarrow N_1 Z N_1 Z \rightarrow N_1 N_1 \ell^+ \ell^- q\bar{q}$ leads to a detector signature of two charged leptons, two jets and large missing transverse momentum. In 4 fb$^{-1}$ of data from collisions recorded by the CDF detector in proton-antiproton collisions at the Tevatron with center-of-mass energy of 1.96 TeV, we find agreement between data and standard model backgrounds. We continue to find cross-section limits in the magnitude of 300 fb, and yield limits in the magnitude of 4 events.

Conference Note