Search for a Higgs Boson in the Decay Channel $H$ to ZZ(*) to $q$ Qbar $\ell-̂$ L+ in $pp$ Collisions at $\sqrt{s}

Search for a Higgs Boson in the Decay Channel $H$ to ZZ(*) to $q$ Qbar $\ell-̂$ L+ in $pp$ Collisions at $\sqrt{s}
Title Search for a Higgs Boson in the Decay Channel $H$ to ZZ(*) to $q$ Qbar $\ell-̂$ L+ in $pp$ Collisions at $\sqrt{s} PDF eBook
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Release 2012
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Download Search for a Higgs Boson in the Decay Channel $H$ to ZZ(*) to $q$ Qbar $\ell-̂$ L+ in $pp$ Collisions at $\sqrt{s} Book in PDF, Epub and Kindle

A search for the standard model Higgs boson decaying into two Z bosons with subsequent decay into a final state containing two quark jets and two leptons, H to ZZ(*) to q q-bar l-l+ is presented. Results are based on data corresponding to an integrated luminosity of 4.6 inverse femtobarns of proton-proton collisions at sqrt(s)=7 TeV, collected with the CMS detector at the LHC. In order to discriminate between signal and background events, kinematic and topological quantities, including the angular spin correlations of the decay products, are employed. Events are further classified according to the probability of the jets to originate from quarks of light or heavy flavor or from gluons. No evidence for the Higgs boson is found, and upper limits on its production cross section are determined for a Higgs boson of mass between 130 and 600 GeV.

Search for the Standard Model Higgs Boson in the Decay Channel $H$ to $Z Z$ to 4 Leptons in $pp$ Collisions at $\sqrt{s}

Search for the Standard Model Higgs Boson in the Decay Channel $H$ to $Z Z$ to 4 Leptons in $pp$ Collisions at $\sqrt{s}
Title Search for the Standard Model Higgs Boson in the Decay Channel $H$ to $Z Z$ to 4 Leptons in $pp$ Collisions at $\sqrt{s} PDF eBook
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Release 2012
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Download Search for the Standard Model Higgs Boson in the Decay Channel $H$ to $Z Z$ to 4 Leptons in $pp$ Collisions at $\sqrt{s} Book in PDF, Epub and Kindle

A search for a Higgs boson in the four-lepton decay channel H to ZZ, with each Z boson decaying to an electron or muon pair, is reported. The search covers Higgs boson mass hypotheses in the range 110 mH

Discovery of a Higgs Boson in the H to ZZ to 4 Leptons Channel

Discovery of a Higgs Boson in the H to ZZ to 4 Leptons Channel
Title Discovery of a Higgs Boson in the H to ZZ to 4 Leptons Channel PDF eBook
Author Adish Pradeep Vartak
Publisher
Pages 206
Release 2014
Genre
ISBN 9781303948466

Download Discovery of a Higgs Boson in the H to ZZ to 4 Leptons Channel Book in PDF, Epub and Kindle

A search for the standard model Higgs boson is presented using data collected in pp collisions at the LHC with the CMS detector. Two distinct Higgs boson decay channels are analyzed. The H --> ZZ --> 2l2[Nu] channel, where l = e or [mu], is analyzed with data collected in 2011 at sqrt(s) = 7 TeV corresponding to an integrated luminosity of 4.6 fb−1. No significant excess of events is observed above the background expectation and the presence of a standard model Higgs boson is excluded in the mass range 270-440 GeV at 95% confidence level. The H --> ZZ --> 4l channel is analyzed with data collected in 2011 and 2012 corresponding to integrated luminosities of 5.1 and 19.7 fb−1 at sqrt(s) = 7 and 8 TeV respectively. A new boson is observed with a local significance of 6.7 standard deviations. The mass of this particle is measured to be 125.6±0.4(stat)±0.2(syst) GeV, and it has a signal strength of 1.04+0.29/-0.25(stat) +0.14/-0.08(syst) relative to the standard model Higgs boson expectation. The width of this particle is measured to be less than 3.6 GeV at 95% confidence level. The spin and parity of this particle is found to be consistent with the standard model Higgs boson.

Search for a Higgs Boson Decaying Into $\gamma*̂\gamma\to\ell\ell\gamma$ with Low Dilepton Mass in Pp Collisions at $\sqrt{s}

Search for a Higgs Boson Decaying Into $\gamma*̂\gamma\to\ell\ell\gamma$ with Low Dilepton Mass in Pp Collisions at $\sqrt{s}
Title Search for a Higgs Boson Decaying Into $\gamma*̂\gamma\to\ell\ell\gamma$ with Low Dilepton Mass in Pp Collisions at $\sqrt{s} PDF eBook
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Pages 22
Release 2015
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ISBN

Download Search for a Higgs Boson Decaying Into $\gamma*̂\gamma\to\ell\ell\gamma$ with Low Dilepton Mass in Pp Collisions at $\sqrt{s} Book in PDF, Epub and Kindle

Our search is described for a Higgs boson decaying into two photons, one of which has an internal conversion to a muon or an electron pair (ll?). The analysis is performed using proton–proton collision data recorded with the CMS detector at the LHC at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.7 fb-1. The events selected have an opposite-sign muon or electron pair and a high transverse momentum photon. No excess above background has been found in the three-body invariant mass range 120 mll? 150 GeV, and limits have been derived for the Higgs boson production cross section times branching fraction for the decay H → ?*? → ll?, where the dilepton invariant mass is less than 20 GeV. A Higgs boson with mH=125 GeV has a 95% confidence level (CL) exclusion observed (expected) limit is 6.7 (5.9sup+2.8/supsub-1.8/sub ) times the standard model prediction. Additionally, an upper limit at 95% CL on the branching fraction of H → (J/?)? for the 125 GeV Higgs boson is set at 1.5 × 10

Search for the Standard Model Higgs Boson in the H ZZ L + L - Qq Decay Channel at CMS

Search for the Standard Model Higgs Boson in the H ZZ L + L - Qq Decay Channel at CMS
Title Search for the Standard Model Higgs Boson in the H ZZ L + L - Qq Decay Channel at CMS PDF eBook
Author Francesco Pandolfi
Publisher
Pages 146
Release 2013-09-30
Genre
ISBN 9783319009049

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Search for a Higgs Boson in the Mass Range from 145 to 1000 GeV Decaying to a Pair of W Or Z Bosons

Search for a Higgs Boson in the Mass Range from 145 to 1000 GeV Decaying to a Pair of W Or Z Bosons
Title Search for a Higgs Boson in the Mass Range from 145 to 1000 GeV Decaying to a Pair of W Or Z Bosons PDF eBook
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Pages 50
Release 2015
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ISBN

Download Search for a Higgs Boson in the Mass Range from 145 to 1000 GeV Decaying to a Pair of W Or Z Bosons Book in PDF, Epub and Kindle

A search for a heavy Higgs boson in the H 2!WW and H 2!ZZ decay channels is reported. The search is based upon proton-proton collision data samples corresponding to an integrated luminosity of up to 5.1 fb-1 at [arrow]" = 7 TeV and up to 19.7fb-1 at [arrow]" = 8 TeV, recorded by the CMS experiment at the CERN LHC. Several final states of the H 2!WW and H 2!ZZ decays are analyzed. The combined upper limit at the 95% confidence level on the product of the cross section and branching fraction exclude a Higgs boson with standard model-like couplings and decays in the range 145

Discovery of the Higgs Boson, Measurements of Higgs Boson Properties, and Search for High Mass Beyond the Standard Model Scalar Particle in the Diphoton Final State with the ATLAS Detector at the Large Hadron Collider

Discovery of the Higgs Boson, Measurements of Higgs Boson Properties, and Search for High Mass Beyond the Standard Model Scalar Particle in the Diphoton Final State with the ATLAS Detector at the Large Hadron Collider
Title Discovery of the Higgs Boson, Measurements of Higgs Boson Properties, and Search for High Mass Beyond the Standard Model Scalar Particle in the Diphoton Final State with the ATLAS Detector at the Large Hadron Collider PDF eBook
Author Hongtao Yang
Publisher
Pages 0
Release 2016
Genre
ISBN

Download Discovery of the Higgs Boson, Measurements of Higgs Boson Properties, and Search for High Mass Beyond the Standard Model Scalar Particle in the Diphoton Final State with the ATLAS Detector at the Large Hadron Collider Book in PDF, Epub and Kindle

With 4.8~$\rm{fb}^{-1}$ of proton-proton collision data collected at $\sqrt{s}=7~\rm{TeV}$ in 2011, and 5.9~$\rm{fb}^{-1}$ collected at $\sqrt{s}=8~\rm{TeV}$ in 2012 by the ATLAS detector at the Large Hadron Collider, an excess of 4.5 standard deviations from the background-only hypothesis is observed near 126.5~GeV in the diphoton invariant mass spectra. Along with the excesses observed in the $H \rightarrow ZZ^{(*)}\rightarrow \ell\ell\ell\ell$ and $H \rightarrow WW^{(*)}\rightarrow \ell\nu\ell\nu$ channels, the observation of a Higgs-like particle is established at 6.0 standard deviations level. With more data accumulated during LHC Run~1, the measurements of Higgs boson couplings and mass in the $H\to\gamma\gamma$ channel are conducted by the ATLAS experiment based on 4.5~$\rm{fb}^{-1}$ of proton-proton collisions at $\sqrt{s}=7~\rm{TeV}$ collected in 2011, and 20.3~$\rm{fb}^{-1}$ at $\sqrt{s}=8~\rm{TeV}$ collected in 2012. The combined signal strength, defined as number of observed Higgs boson decays to diphoton divided by the corresponding Standard Model prediction, is measured to be $1.17 \ ^{+0.28}_{-0.26}$ assuming the Higgs boson mass being 125.4~$\rm{GeV}$. The signal strengths for individual Higgs boson production processes are also measured, and are found to be in good consistency with the Standard Model. The mass of the Higgs boson is measured in $H\to\gamma\gamma$ channel by the ATLAS experiment to be $125.98 \pm 0.50$~\GeV. This measurement is combined with the ones from ATLAS $H \rightarrow ZZ^{(*)}\rightarrow \ell\ell\ell\ell$ as well as CMS $H\to\gamma\gamma$ and $H \rightarrow ZZ^{(*)}\rightarrow \ell\ell\ell\ell$. The Higgs boson mass measured from the combination is $125.09\pm0.24~\rm{GeV}$. With LHC center-of-mass energy increased to 13~TeV, a search for high mass Beyond the Standard Model scalar resonance is performed in the diphoton decay channel based on 15.4~$\rm{fb}^{-1}$ of proton-proton collision data collected by the ATLAS detector during 2015 and 2016. While a notable wide excess was first observed in the diphoton invariant mass spectrum from the 2015 data (3.2~$\rm{fb}^{-1}$) with mass near 750~GeV, it is not confirmed by the 2016 data with much higher statistics (12.4~$\rm{fb}^{-1}$). Limits on the production cross section times branching ratio of such resonances are set.