Search for charged Higgs boson in ttbar in pp collisions at
TeV
Main Results
The large top quark production cross section at the Large Hadron Collider offers the opportunity to search for the
charged Higgs boson as the decay

can be large in extensions of the standard model,
if the mass is lighter than the top quark mass. A direct search for the charged Higgs boson in events with one lepton (electron or muon), at least two jets,
missing transverse energy, and one hadronically decaying tau lepton has been performed in 36 pb

of data collected in proton-proton collisions at
TeV.
We do not find a signal in our search and derive an upper limit on the branching ratio

for masses between 80 and 140GeV/

, when assuming

.
Figure |
Label |
Description |
|
Figure 6 |
The relation between and the upper limit on for the observed and the expected limit with error band shown in yellow color for =120~GeV/c , where is assumed. |
|
Figure 5 |
Expected number of events after the final event selection as a function of the branching ratio for =120 GeV/ . Expectations are also shown separately for WH, HH and (WW) contributions. |
|
Figure 4, right |
Probability that a jet fakes a -jet as obtained from the QCD multi-jet events taken during runs with and without pileup. |
|
Figure 3 |
Data and MC event yields at various levels of the selection. |
|
Figure 2, left |
Jet multiplicity distribution ( GeV/c, ) after requiring one isolated lepton. |
|
Figure 2, right |
MET distribution for events with one isolated lepton and at least two jets; the hatched area shows the uncertainty. The last bin includes the events in the overflow bins. |
|
Figure 7 |
Upper limit on assuming as a function of . The yellow band shows the band around the expected limit. |
|
Figure 4, left |
Inclusive jet distribution for jet events after the MET cut, and with at least two jets with 30 GeV/c and at least one jet with 20 GeV/c. Entries in the last bin include the overflows. |
|
Table 1 |
The systematics uncertainties for backgrounds, signal events from (HH) and (WH) processes at . These systematic uncertainties are given as the input for the exclusion limit calculation. |
|
Table 2 |
Number of expected events for the backgrounds, signal events from (HH) and (WH) processes at =120 GeV/ , and the number of observed events after the final event selection. Statistical and systematic uncertainties are shown. The statistical uncertainties are due to MC statistics, while for the $\tau$-fakes the statistical uncertainties are due to the fake rate in the data. Of the 40 events found in the data, 16~(24) events are in the ( ) final state, which is expected as the electron efficiency is lower than the muon efficiency. |
--
MicheleGallinaro - 14-Mar-2011