Mon Mar 13 19:12:38 CST 1995
Search for New Particles Decaying to B-Tagged Dijets
We present a search for new particles decaying to b-tagged dijets
using CDF data from the 1992-3 run. The analysis is identical to the
plain dijet search (FERMILAB-Pub-94/405-E),
except we require at least one of the two leading
jets to have a secondary vertex found by our silicon vertex detector.
The b-tagged dijet mass spectrum
extends from 150 to 650 GeV and is found to be a smoothly falling distribution
within statistics. the
highest mass double b-tagged event has a
mass of 256 GeV.
We search the b-tagged dijet mass spectrum for the effect
of new particles decaying to 
mass resonances. We especially search
for topcolor (PL B345, 483 (1995)) a model which seeks to explain
the mass of the top quark by introducing a new SU(3) and U(1) symmetry coupled
to the third generation. Fitting the data to a
smooth background function plus a mass resonance we obtain 95% confidence
level upper limits on the cross
section for new particles
as a function of mass. We search for narrow resonances that could be produced
by a color octet technirho, a standard Z', or a topcolor
Z'. We also search for broad resonances that are produced by
topcolor octet gauge bosons: topgluons defined by case C in
PRD49, 4454 (1994).
This preliminary analysis excludes at 95% CL topgluons in the mass range:
200<M<550 GeV for width 
= 0.11 M
210<M<450 GeV for width 
= 0.3 M
200<M<370 GeV for width 
= 0.5 M
Preliminary excluded regions are shown in the width vs. mass and SU(3) mixing vs.
mass plane. The search continues: data from the 1994-95 run is currently being
analyzed.
rharris@fnald.fnal.gov
Mon Mar 13 19:12:37 CST 1995