Search for associated Higgs (VH) Production withH → W+W− → lνlν and hadronic V decay
This is a condensed description with plots for the analysis
CMS-HIG-12-014
Abstract
A search for the associated Higgs production (VH) is reported for Higgs boson decays
via WW bosons in fully leptonic final states, accompanied by a vector boson V decaying
into two hadronic jets.
The analysis uses pp collision data at √s = 7
TeV from
the LHC corresponding to an integrated luminosity of 4.9/fb recorded by the
CMS detector in 2011.
No significant excess of events above the standard model background expectations
is observed for a selection of event candidates with with two leptons, electrons or muons,
large missing transverse energy and two jets.
Upper limits on the Higgs boson production relative to the standard model Higgs expectation
are obtained for a Higgs boson in the mass range 120-190
GeV.
Main Results
A search has been made for Higgs bosons with VH → W
+W
− → lνlν
and hadronic V decay in the pp collision 2011 data at √s = 7 TeV with the CMS detector.
A cut and count analysis is performed, optimized for each mass point.
The main backgrounds (top, Drell Yan, W+jets) are estimated
with data-driven techniques.
The W
+W
-, WZ, ZZ, Vγ backgrounds are taken from Monte Carlo expectations.
No evidence of Higgs boson is found and the results are interpreted as an exclusion of a H mass range.
Below we report the table with the exclusion limits for a range of masses 118-190 GeV/c
2.
Higgs Mass |
Observed |
Median exp. |
68% band |
95% band |
118 |
17.9 |
21.15 |
[ 14.82 , 32.60 ] |
[ 8.81 , 48.72 ] |
120 |
13.0 |
15.50 |
[ 10.86 , 23.74 ] |
[ 6.21 , 35.24 ] |
124 |
9.4 |
12.89 |
[ 9.13 , 19.89 ] |
[ 4.51 , 29.29 ] |
128 |
7.5 |
9.49 |
[ 6.51 , 14.82 ] |
[ 3.90 , 19.23 ] |
130 |
5.8 |
8.03 |
[ 5.45 , 12.38 ] |
[ 3.43 , 15.18 ] |
135 |
7.1 |
7.10 |
[ 4.93 , 10.91 ] |
[ 3.10 , 14.68 ] |
140 |
4.3 |
4.75 |
[ 3.29 , 7.28 ] |
[ 2.05 , 10.70 ] |
150 |
4.5 |
3.71 |
[ 2.65 , 5.62 ] |
[ 1.79 , 8.40 ] |
160 |
3.3 |
3.13 |
[ 2.17 , 4.83 ] |
[ 1.32 , 7.30 ] |
170 |
3.1 |
2.91 |
[ 2.02 , 4.46 ] |
[ 1.34 , 6.81 ] |
180 |
4.0 |
3.81 |
[ 2.64 , 5.95 ] |
[ 1.64 , 8.93 ] |
190 |
6.1 |
6.17 |
[ 4.31 , 9.61 ] |
[ 3.17 , 14.55 ] |
Two opposite charged leptons, large missing transverse energy and two jets are required.
The invariant mass of the di-jets system is required to be around the W/Z mass (mjj ∈[60,110]
GeV).
Figure |
Label |
Description |
|
Figure 1 pdf, eps, png |
The invariant mass of the jets mjj at WW level normalized to luminosity for mH =160 GeV SM Higgs hypothesis and for the main backgrounds. Backgrounds are normalized with data-driven techniques and signals are plotted one on top of the other. The error band on the expected rates reflects the Monte Carlo statistics and the systematic error coming from data driven estimation. |
|
Figure 2 pdf, eps, png |
The invariant mass of the jets mjj at Higgs level normalized to luminosity for mH =160 GeV SM Higgs hypothesis and for the main backgrounds. Backgrounds are normalized with data-driven techniques and signals are plotted one on top of the other. The error band on the expected rates reflects the Monte Carlo statistics and the systematic error coming from data driven estimation. |
|
Figure 3 pdf, eps, png |
95% expected and observed C.L. upper limits on the cross section times branching ratio, σ Higgs * BR(H → W+W− → lνlν), relative to the SM value. Results are obtained using the CLs approach. |
|
Figure 4 pdf, eps, png |
95% expected and observed C.L. upper limits on the cross section times branching ratio, σ Higgs * BR(H → W+W− → lνlν), relative to the Fermiophobic Higgs scenario value. Results are obtained using the CLs approach. |
--
AndreaMassironi - 24-May-2012