Search for the Standard Model Higgs Boson in the Diphoton Final State in $p\bar{p}$ Collisions at $\sqrt{s}$

Search for the Standard Model Higgs Boson in the Diphoton Final State in $p\bar{p}$ Collisions at $\sqrt{s}$
Title Search for the Standard Model Higgs Boson in the Diphoton Final State in $p\bar{p}$ Collisions at $\sqrt{s}$ PDF eBook
Author
Publisher
Pages
Release 2012
Genre
ISBN

Download Search for the Standard Model Higgs Boson in the Diphoton Final State in $p\bar{p}$ Collisions at $\sqrt{s}$ Book in PDF, Epub and Kindle

We present a search for the Standard Model Higgs boson decaying into a pair of photons produced in p$p\bar{p}$ collisions with a center of mass energy of 1.96 TeV. The results are based on data corresponding to an integrated luminosity of 10 fb-1 collected by the CDF II detector. Higgs boson candidate events are identified by reconstructing two photons in either the central or plug regions of the detector. The acceptance for identifying photons is significantly increased by using a new algorithm designed to reconstruct photons in the central region that have converted to an electron-positron pair. In addition, a new neural network discriminant is employed to improve the identification of non-converting central photons. No evidence for the Higgs boson is observed in the data, and we set an upper limit on the cross section for Higgs boson production multiplied by the H 2![gamma][gamma] branching ratio. For a Higgs boson mass of 125 GeV/c 2, we obtain an observed (expected) limit of 12.2 (10.8) times the Standard Model prediction at the 95% credibility level.

Search for a Higgs Boson in the Diphoton Final State in P-pbar Collisions at Sqrt(s)

Search for a Higgs Boson in the Diphoton Final State in P-pbar Collisions at Sqrt(s)
Title Search for a Higgs Boson in the Diphoton Final State in P-pbar Collisions at Sqrt(s) PDF eBook
Author
Publisher
Pages
Release 2011
Genre
ISBN

Download Search for a Higgs Boson in the Diphoton Final State in P-pbar Collisions at Sqrt(s) Book in PDF, Epub and Kindle

A search for a narrow Higgs boson resonance in the diphoton mass spectrum is presented based on data corresponding to 7.0 fb−1 of integrated luminosity from p{bar p} collisions at √s = 1.96 TeV collected by the CDF experiment. No evidence of such a resonance is observed, and upper limits are set on the cross section times branching ratio of the resonant state as a function of Higgs boson mass. The limits are interpreted in the context of the standard model and one fermiophobic benchmark model where the data exclude fermiophobic Higgs bosons with masses below 114 GeV/c2 at a 95% Bayesian credibility level.

Search for the Standard Model Higgs Boson Decaying to a $W$ Pair in the Fully Leptonic Final State in $pp$ Collisions at $\sqrt{s}

Search for the Standard Model Higgs Boson Decaying to a $W$ Pair in the Fully Leptonic Final State in $pp$ Collisions at $\sqrt{s}
Title Search for the Standard Model Higgs Boson Decaying to a $W$ Pair in the Fully Leptonic Final State in $pp$ Collisions at $\sqrt{s} PDF eBook
Author
Publisher
Pages 113
Release 2012
Genre
ISBN

Download Search for the Standard Model Higgs Boson Decaying to a $W$ Pair in the Fully Leptonic Final State in $pp$ Collisions at $\sqrt{s} Book in PDF, Epub and Kindle

A search for the standard model Higgs boson decaying to W+W- in pp collisions at sqrt(s) = 7 TeV is reported. The data are collected at the LHC with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. The W+W- candidates are selected in events with two charged leptons and large missing transverse energy. No significant excess of events above the standard model background expectations is observed, and upper limits on the Higgs boson production relative to the standard model Higgs expectation are derived. The standard model Higgs boson is excluded in the mass range 129-270 GeV at 95% confidence level.

Search for a Standard Model-like Higgs Boson in the Mass Range Between 70 and 110 GeV in the Diphoton Final State in Proton-proton Collisions at √s

Search for a Standard Model-like Higgs Boson in the Mass Range Between 70 and 110 GeV in the Diphoton Final State in Proton-proton Collisions at √s
Title Search for a Standard Model-like Higgs Boson in the Mass Range Between 70 and 110 GeV in the Diphoton Final State in Proton-proton Collisions at √s PDF eBook
Author Albert M. Sirunyan
Publisher
Pages
Release 2018
Genre
ISBN

Download Search for a Standard Model-like Higgs Boson in the Mass Range Between 70 and 110 GeV in the Diphoton Final State in Proton-proton Collisions at √s Book in PDF, Epub and Kindle

Combined Results of Searches for the Standard Model Higgs Boson in Pp Collisions at Sqrt(s)

Combined Results of Searches for the Standard Model Higgs Boson in Pp Collisions at Sqrt(s)
Title Combined Results of Searches for the Standard Model Higgs Boson in Pp Collisions at Sqrt(s) PDF eBook
Author
Publisher
Pages
Release 2012
Genre
ISBN

Download Combined Results of Searches for the Standard Model Higgs Boson in Pp Collisions at Sqrt(s) Book in PDF, Epub and Kindle

Combined results are reported from searches for the standard model Higgs boson in proton-proton collisions at sqrt(s)=7 TeV in five Higgs boson decay modes: gamma pair, b-quark pair, tau lepton pair, W pair, and Z pair. The explored Higgs boson mass range is 110-600 GeV. The analysed data correspond to an integrated luminosity of 4.6-4.8 inverse femtobarns. The expected excluded mass range in the absence of the standard model Higgs boson is 118-543 GeV at 95% CL. The observed results exclude the standard model Higgs boson in the mass range 127-600 GeV at 95% CL, and in the mass range 129-525 GeV at 99% CL. An excess of events above the expected standard model background is observed at the low end of the explored mass range making the observed limits weaker than expected in the absence of a signal. The largest excess, with a local significance of 3.1 sigma, is observed for a Higgs boson mass hypothesis of 124 GeV. The global significance of observing an excess with a local significance greater than 3.1 sigma anywhere in the search range 110-600 (110-145) GeV is estimated to be 1.5 sigma (2.1 sigma). More data are required to ascertain the origin of this excess.

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 156
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.

Search for the Standard Model Higgs Boson in the ZH-]vvbb Channel in 5.2 Fb-1 of P-pbar Collisions at Sqrt(s)

Search for the Standard Model Higgs Boson in the ZH-]vvbb Channel in 5.2 Fb-1 of P-pbar Collisions at Sqrt(s)
Title Search for the Standard Model Higgs Boson in the ZH-]vvbb Channel in 5.2 Fb-1 of P-pbar Collisions at Sqrt(s) PDF eBook
Author
Publisher
Pages
Release 2009
Genre
ISBN

Download Search for the Standard Model Higgs Boson in the ZH-]vvbb Channel in 5.2 Fb-1 of P-pbar Collisions at Sqrt(s) Book in PDF, Epub and Kindle

A search is performed for the standard model Higgs boson in 5.2 fb−1 of p{bar p} collisions at √s = 1.96 TeV, collected with the D0 detector at the Fermilab Tevatron Collider. The final state considered is a pair of b jets and large missing transverse energy, as expected from p{bar p} → ZH → [nu]{bar [nu]}b{bar b} production. The search is also sensitive to the WH → l{nu}b{bar b} channel when the charged lepton is not identified. For a Higgs boson mass of 115 GeV, a limit is set at the 95% C.L. on the cross section multiplied by branching fraction for (p{bar p} → (Z/W)H) x (H → b{bar b}) that is a factor of 3.7 larger than the standard model value, consistent with the factor of 4.6 expected.