Search for Neutral Higgs Bosons Decaying to Tau Pairs in pp Collisions at sqrt(s)=7 TeV

This is a condensed description with plots for the analysis CMS-HIG-11-009

Abstract

A search for neutral Higgs bosons in pp collisions at the LHC at a center-of-mass energy of 7 TeV is presented. The results are based on a data sample corresponding to an integrated luminosity of 1.1/fb recorded by the CMS experiment. The search uses decays of the Higgs bosons to tau pairs, including the cases where the Higgs boson is produced in association with a b-quark jet (MSSM search) or two forward jets from vector boson fusion Higgs boson production (SM search). No excess is observed in the tau-pair invariant-mass spectrum. The resulting upper limits on the Higgs boson production cross section times branching fraction to tau pairs, as a function of the pseudoscalar Higgs boson mass, yield stringent new bounds in the MSSM parameter space.

Main Results

A measurement of this search are the 95% CL limits on the standard model cross section and the 95% exclusion limit in the MSSM tan beta - ma plane.

SM Higgs boson limit table

mass	obs	-95%	-68%	median	+68%	+95%
110	8.767	4.465	5.971	8.349	11.921	16.432
115	8.799	4.638	6.666	9.005	12.750	17.389
120	10.037	4.189	5.973	8.365	12.128	16.564
125	9.466	4.439	6.116	8.729	12.222	17.070
130	9.559	4.761	6.845	9.505	13.377	18.856
135	11.170	6.836	8.724	11.750	16.903	22.858
140	14.295	7.482	9.974	14.265	20.005	26.953

Text files with limits etc.

• Cross Section Limits (text file)

MSSM Higgs boson limit table

mass	obs	-95%	-68%	median	+68%	+95%
90	52.670	10.806	15.805	21.803	32.001	44.675
100	26.280	6.603	11.048	15.669	22.319	30.425
120	11.729	3.779	4.982	6.876	9.875	13.353
130	9.620	2.898	3.875	5.574	7.972	10.644
140	7.682	2.096	2.824	4.068	5.728	7.695
160	5.499	1.631	2.095	2.908	4.150	5.743
180	3.791	1.133	1.490	2.087	2.977	4.079
200	2.937	0.927	1.249	1.708	2.470	3.416
250	1.495	0.553	0.807	1.093	1.520	2.065
300	0.820	0.405	0.527	0.770	1.087	1.465
400	0.533	0.228	0.311	0.432	0.614	0.834
450	0.452	0.157	0.231	0.329	0.464	0.633
500	0.432	0.131	0.187	0.271	0.372	0.509

Text files with limits etc.

• Cross Section Limits (text file)

Figures from CMS-HIG-11-009

Figure	Links	Description
	Figure 0 pdf,png	Visible mass in the e-tau channel, in the no b-Tag category.
	Figure 1 pdf,png	Visible mass in the mu-tau channel, in the no b-Tag category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 2 pdf,png	Visible mass in the e-mu channel, in the no b-Tag category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 3 pdf, png	Visible mass in the mu-mu channel, in the no b-Tag category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 4 pdf, png	Visible mass in the e-tau channel, in the b-Tag category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 5 pdf, png	Visible mass in the mu-tau channel, in the b-Tag category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 6 pdf,png	Visible mass in the e-mu channel, in the b-Tag category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 7 pdf,png	Visible mass in the mu-mu channel, in the b-Tag category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 8 pdf, png	Visible mass in the e-tau channel, in the Non-VBF category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 9 pdf,png	Visible mass in the mu-tau channel, in the Non-VBF category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 10 pdf,png	Visible mass in the e-mu channel, in the Non-VBF category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 11 pdf,png	Visible mass in the mu-mu channel, in the Non-VBF category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 12 pdf, png	Visible mass in the e-tau channel, in the VBF category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 13 pdf, png	Visible mass in the mu-tau channel, in the VBF category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 14 pdf, png	Visible mass in the e-mu channel, in the VBF category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 15 pdf, png	Visible mass in the mu-mu channel, in the VBF category. The MC histograms have been normalized to the number of the expected events after the fit.
	Figure 16 pdf,png	The expected one- and two-standard-deviation ranges and observed 95% CL upper limits on cross section time as a function of mA. The signal acceptance is based on the MSSM model described in the text, assuming tan beta=30.
	Figure 17 pdf, png	The expected one- and two-standard-deviation ranges and observed 95% CL upper limits on cross section time branching ratio normalized to the SM expectation as a function of mH.

Additional plots for public talks

Figure	Links	Description
	Figure 18 png	Reconstructed number of jets in the e-mu channel
	Figure 19 png	econstructed number of b-tagged jets in the e-mu channel
	Figure 20 png	Distribution of the b-tag discriminator in the e-mu channel
	Figure 21 png	Distribution of the di-Jet invariant mass for the two VBF jets in the e-mu channel
	Figure 22 png	Delta eta distribution of the two VBF jets in the e-mu channel
	Figure 23 png	VBF candidate event in the mu-tau channel (muPt=19.8 GeV, tauPt=69.3, MET=97 GeV, j1 pt = 177 GeV / eta=-1.9, j2 pt = 46 eta = 1.6, mjj=580 GeV)
	Figure 24 png	Distribution of the (Pmiss - 0.85 Pvis) variable in the e-mu channel
	Figure 25 pdf,png	Distribution of the (Pzeta - 1.5*Pvis) variable for opposite sign mu-tau pairs, Pzeta = Pmiss + Pvis. No scale factors have been used from the Monte Carlo samples, this figure is intended only for illustrative purpose to show the OS / SS method for background estimation.
	Figure 26 pdf,png	Distribution of the (Pzeta - 1.5*Pvis) variable for same sign mu-tau pairs, Pzeta = Pmiss + Pvis.
	Figure 27 pdf,png	Region in the parameter space of tan beta versus mA excluded at 95% CL in the context of the MSSM m^max_h scenario, with the effect of +/- 1 sigma theoretical uncertainties shown. The exclusion limit obtained form 2010 data is shown with a dark blue line. The other shaded regions show the 95% CL excluded regions from the LEP and Tevatron experiments.
	Figure 28 png	Tag and Probe: Visible mass distribution in the pass samples for the mu-tau channel. The shape templates are scaled by normalization factors obtained by the ``extended'' fit model.
	Figure 29 png	Tag and Probe: Visible mass distribution in the failed samples for the mu-tau channel. The shape templates are scaled by normalization factors obtained by the ``extended'' fit model.
	Figure 30 png	Acceptance time efficiency for the inclusive tau tau selection for the e-tau, mu-tau and e-mu final state.
	Figure 31 png	Acceptance time efficiency for the b-tag tau tau selection for the e-tau, mu-tau and e-mu final state.
	Figure 32 png	Acceptance time efficiency for the non-b-tag tau tau selection for the e-tau, mu-tau and e-mu final state.
	Figure 33 png	Acceptance time efficiency for the VBF tau tau selection for the e-tau, mu-tau and e-mu final state.
	Figure 34 png	Acceptance time efficiency for the non-VBF tau tau selection for the e-tau, mu-tau and e-mu final state.
	Figure 35 png	Expected limit on the SM cross section for the different decay channels.
	Figure 36 png	Observed limit on the SM cross section for the different decay channels.
	Figure 37 png	Expected limit on the MSSM cross section for the different decay channels.
	Figure 38 png	Observed limit on the MSSM cross section for the different decay channels.
	Figure 39 pdf,png	Region in the parameter space of tan beta versus mA excluded at 95% CL in the context of the MSSM m^max_h scenario, with the effect of +/- 1 sigma theoretical uncertainties shown. The CMS charged Higgs result is shown in dark blue. The other shaded regions show the 95% CL excluded regions from the LEP and Tevatron experiments. All the limits shown (CMS, LEP and Tevatron), apart from the CMS charged Higgs result, are obtained with phi->tau tau searches.
	Figure 39 pdf,png	Distribution of the likelihood variable, discriminating H->TauTau signal and background processes in the mu-mu channel.

| | Figure 39 pdf,png | Distribution of the ratio of the dimuon transverse momentum to the scalar sum of muon transverse momenta in a sample of preselected dimuon events; variable is used in the construction of the likelihood discriminant in the mu-mu channel. |

	Figure 39 pdf,png	Distribution of dimuon pseudo-rapidity in a sample of preselected dimuon event; variable is used in the construction of the likelihood discriminant in the mu-mu channel.
	Figure 39 pdf,png	Distribution of delta(beta)-corrected relative PFlow-based muon isolation variable in the mu-mu channel.
	Figure 39 pdf,png	Distribution of inter-muon distance of closest approach significance in a sample of preselected dimuon events; variable is used in the construction of the likelihood discriminant in the mu-mu channel.
	Figure 39 pdf,png	Distribution of missing transverse energy in a sample of preselected dimuon events in the mu-mu channel.