Search for WWW* from W Higgs Associated Production

Search for WWW* from W Higgs Associated Production

We search for neutral Higgs production associated with the W boson using high-pT isolated like-sign (LS) dilepton events in the 193.5 pb^-1 CDF Run II data. We first study the background components in our base-line like-sign sample which is created by requiring the leading lepton p_T > 20 GeV/c and the second lepton p_T > 6 GeV/c, and confirm that, overall, the entire sample is consistent with out background expectation. Based on the S/sqrt{B} calculated from signal Monte Carlo's and our background expectation, the signal region is then determined in the plane of the second lepton p_T (p_T2) versus the vector sum of p_T's of the two leptons(p_T12). The signal region is p_T2 > 16 (18) GeV/c and p_T12 > 35 GeV/c for the Higgs masses < 160 GeV/c**2 (> 160 GeV/c**2). No event is found, while the total background is expected to be 0.95 +- 0.61(stat) +- 0.18(syst) events, the 110 GeV/c**2 bosophilic (fermiophobic) Higgs to be about 0.06 events assuming the same production cross section as the Standard Model Higgs, and the 160 GeV/c**2 Standard Model Higgs to be about 0.03 events. We set cross section upper limits sigma(WH) * BR(H->WW) < 12 pb at 95% C.L. for the 110 GeV/c**2 Higgs and 8 pb for the 160 GeV/c**2 Higgs. The analysis is structured from simple techniques only: conventional isolation, high-p_T lepton identification, and simple kinematical requirements to define the signal region. There are no signal-specific cuts such as missing E_T and other topological cuts. The present result therefore provides a conservative physics interpretation.

Contacts: Hirokazu Kobayashi, Yoshihiro Seiya, and Kazuhiro Yamamoto
Data: Run II, 194 pb^-1
Documentation: PS, PDF

Plots and Tables:

Conversion Study and Estimate:
	Right and wrong side track delta z distribution in the low p_T electron dataset, EPS, JPG, or GIF.
	Total photon conversion tagging efficiency, EPS, JPG, or GIF.
Like-Sign Di-Leptons in the Inclusive Sample:
	The missing E_T, dilepton opening angle, and transverse momentum of the the dilepton system, EPS, JPG, or GIF.
Like-Sign Di-Leptons in the Lepton Plus Track Sample:
	The missing E_T, dilepton opening angle, and transverse momentum of the the dilepton system, EPS, JPG, or GIF.
Defining the Signal Region:
	Comparison of expected and observed number of events in the plane of p_T lepton two versus dilepton vector sum p_T, EPS, JPG, or GIF.
W Higgs Signal Acceptance:
	Total signal acceptance of W Higgs with Higgs decaying to WW*, EPS, JPG, or GIF, that belong under the same header.
95% Confidence Level Limits:
	Cross-section of W Higgs production times branching ratio of Higgs into W W* upper limit at 95% C.L., EPS, JPG, or GIF.
	Cross-section of W/Z Higgs production times branching ratio of Higgs into W W* or Z Z* upper limit at 95% C.L., EPS, JPG, or GIF.

Page page: http://www-cdf.fnal.gov/physics/exotic/r2a/20041014.lsdilep_whwww/index.html was last updated October 28th, 2004 by Stephan Lammel.
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