2 The CDF Experiment at Fermilab Contents - Harvard University ...

Section 2: Run II Triggers 77
{ Leptoquarks where the leptoquark decays in a quark and a neutrino
{ CHArged Massive Particles (CHAMPS): These are long-lived massive particles
that if they are penetrating enough can go undetected and cause energy imbalance.
{ Gravitons In Kaluza-Klein-type string theories of extra dimensions (where the
extra dimension is physical but has compactied in the sense that for example
the universe in this dimension is small compared to the smallest distances probed
by experiments) the graviton can be produced in high energy hadron collisions
and escape to the extra spatial dimension thus creating an energy imbalance in
the usual 3 spatial dimension space.
The study for the design of the 6E T trigger for Run II is using data from Run Ib. We
calculate the rates for an inclusive 6E T trigger as well as a 6E T plus jets multilevel trigger. At
the lower level (L1) the trigger requires 6E T > 25 GeV. At Level 2 (L2) the 6E T requirement
remains the same and two jets of energy 10 GeV are required (we call it \L2 MET" trigger).
At Level 3 (L3) the 6E T requirement is raised to 35 GeV. Compared to the RunI 6E T trigger,
the rates are about the same although the luminosity is going to be signicantly higher at
Run II. This is because although we lower the L2 6E T threshold from the previous run (30
GeV) the Main Ring that was responsible for more than one third of 6E T triggers at RunI
does not longer exist. In the case of very high luminosity environment the 6E T threshold
would need to be raised. The total trigger rate budget allows for an inclusive L26E T trigger
of 45 GeV which would catch monojet events, photons and other potentially exotic events.
For the L2 MET trigger we present the signal eciency for the following processes:
SUSY, 300 GeV gluinos The upper left plot of Fig. 38 shows the L2 6E T trigger
eciency for squark gluino production as a function of the 6E T trigger threshold and
for the case of inclusive 6E T (solid triangles), of two jets of 6 GeV requirement (open
squares), and two jets of 10 GeV requirement (open circles). The L2 MET trigger for
this SUSY point is more than 90% ecient.
top quark production. The upper right plot of Fig. 38 shows the L2 6E T Trigger
eciency as a function of the 6E T trigger threshold. The L2 MET trigger for top (which
is decaying inclusively) is about 60% ecient.
W/Z Higgs associate production with the subsequent decay channels and Higgs mass
as denoted in the bottom plots of Fig. 38. The L2 MET trigger is between 55% and
65% ecient depending on the process and the decay channels.