# Top Physics

# Top Physics
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ISBN-10 : OCLC:68506620
ISBN-13 :
Rating : 4/5 (20 Downloads)

Synopsis # Top Physics by :

We present a measurement of the t{bar t} production cross section using 194 pb−1 of CDF II data using events with a high transverse momentum electron or muon, three or more jets, and missing transverse energy. The measurement assumes 100% t --> Wb branching fraction. Events consistent with t{bar t} decay are found by identifying jets containing heavy flavor semileptonic decays to muons. The dominant backgrounds are evaluated directly from the data. Based on 20 candidate events and an expected background of 9.5 " 1.1 events, we measure a production cross section of 5.3 " 3.3{sub -1.0}{sup +1.3} pb, in agreement with the standard model.

Measurement of the $t\bar{t}$ Production Cross Section in Pp Collisions at $\sqrt{s}$

Measurement of the $t\bar{t}$ Production Cross Section in Pp Collisions at $\sqrt{s}$
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Total Pages : 21
Release :
ISBN-10 : OCLC:940478687
ISBN-13 :
Rating : 4/5 (87 Downloads)

Synopsis Measurement of the $t\bar{t}$ Production Cross Section in Pp Collisions at $\sqrt{s}$ by :

The top-quark pair production cross section is measured in final states with one electron or muon and one hadronically decaying [tau] lepton from the process $t\bar{t}$ to (l[nu]l) ([tau][nu][tau]) $b\bar{b}$, where l = e, [mu]. The data sample corresponds to an integrated luminosity of 19.6 fb-1 collected with the CMS detector in proton-proton collisions at $\sqrt{s}$ =8 TeV. The measured cross section [sigma]$t\bar{t}$ = 257 ± 3 (stat) ± 24 (syst) ± 7 (lumi) pb, assuming a top-quark mass of 172.5 GeV, is consistent with the standard model prediction.

Measurement of the $WZ$ Production Cross Section in $pp$ Collisions at $\sqrt{s}

Measurement of the $WZ$ Production Cross Section in $pp$ Collisions at $\sqrt{s}
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ISBN-10 : OCLC:958233063
ISBN-13 :
Rating : 4/5 (63 Downloads)

Synopsis Measurement of the $WZ$ Production Cross Section in $pp$ Collisions at $\sqrt{s} by :

The WZ production cross section in proton-proton collisions at sqrt(s) = 13 TeV is measured with the CMS experiment at the LHC using a data sample corresponding to an integrated luminosity of 2.3 inverse femtobarns. The measurement is performed in the leptonic decay modes WZ to l nu l' l', where l, l'= e, mu. The measured cross section for the range 60

Measurement of the Top-antitop Production Cross Section in Pp Collisions at Sqrt(s)

Measurement of the Top-antitop Production Cross Section in Pp Collisions at Sqrt(s)
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Total Pages : 39
Release :
ISBN-10 : OCLC:1066549647
ISBN-13 :
Rating : 4/5 (47 Downloads)

Synopsis Measurement of the Top-antitop Production Cross Section in Pp Collisions at Sqrt(s) by :

A measurement of the top-antitop production cross section in proton-proton collisions at a centre-of-mass energy of 7 TeV has been performed at the LHC with the CMS detector. The analysis uses a data sample corresponding to an integrated luminosity of 36 inverse picobarns and is based on the reconstruction of the final state with one isolated, high transverse-momentum electron or muon and three or more hadronic jets. The kinematic properties of the events are used to separate the top-antitop signal from W+jets and QCD multijet background events. The measured cross section is 173 + 39 - 32 (stat. + syst.) pb, consistent with standard model expectations.

Measurement of the Inclusive Upsilon Production Cross Section in Pp Collisions at Sqrt(s)

Measurement of the Inclusive Upsilon Production Cross Section in Pp Collisions at Sqrt(s)
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ISBN-10 : OCLC:1066661918
ISBN-13 :
Rating : 4/5 (18 Downloads)

Synopsis Measurement of the Inclusive Upsilon Production Cross Section in Pp Collisions at Sqrt(s) by :

The Upsilon production cross section in proton-proton collisions at sqrt(s) = 7 TeV is measured using a data sample collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 3.1 +/- 0.3 inverse picobarns. Integrated over the rapidity range.

Measurement of the Production Cross Section for Pairs of Isolated Photons in Pp Collisions at Sqrt(s)

Measurement of the Production Cross Section for Pairs of Isolated Photons in Pp Collisions at Sqrt(s)
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Total Pages : 38
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ISBN-10 : OCLC:1066567234
ISBN-13 :
Rating : 4/5 (34 Downloads)

Synopsis Measurement of the Production Cross Section for Pairs of Isolated Photons in Pp Collisions at Sqrt(s) by :

The integrated and differential cross sections for the production of pairs of isolated photons is measured in proton-proton collisions at a centre-of-mass energy of 7 TeV with the CMS detector at the LHC. A data sample corresponding to an integrated luminosity of 36 inverse picobarns is analysed. A next-to-leading-order perturbative QCD calculation is compared to the measurements. A discrepancy is observed for regions of the phase space where the two photons have an azimuthal angle difference, $\Delta(\phi)$, less than approximately 2.8.

Measurement of the T Anti-t Cross-Section Using the Dimuon Channel in Ppbar Collisions at Sqrt(s)

Measurement of the T Anti-t Cross-Section Using the Dimuon Channel in Ppbar Collisions at Sqrt(s)
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ISBN-10 : OCLC:68231287
ISBN-13 :
Rating : 4/5 (87 Downloads)

Synopsis Measurement of the T Anti-t Cross-Section Using the Dimuon Channel in Ppbar Collisions at Sqrt(s) by :

The authors have measured the t[bar t] production cross section at [radical]s = 1.96 TeV using data collected by the D0 experiment at Fermilab. The integrated luminosity of the data set is 140 pb[sup -1] and a total of four candidate events are seen, with an expected background of 2.61 events. The measured cross section of [sigma][sub t[bar t]] = 11.1[sub -9.3][sup +22.1](stat.)[sub -4.5][sup +4.3](sys.) pb is in agreement with a NNLO calculation of 6.77 pb.

Measurement of the Production Cross Sections for a Z Boson and One Or More B Jets in Pp Collisions at Sqrt(s)

Measurement of the Production Cross Sections for a Z Boson and One Or More B Jets in Pp Collisions at Sqrt(s)
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Publisher :
Total Pages : 39
Release :
ISBN-10 : OCLC:940479014
ISBN-13 :
Rating : 4/5 (14 Downloads)

Synopsis Measurement of the Production Cross Sections for a Z Boson and One Or More B Jets in Pp Collisions at Sqrt(s) by :

The production of a Z boson, decaying into two leptons and produced in association with one or more b jets, is studied using proton-proton collisions delivered by the LHC at a centre-of-mass energy of 7 TeV. The data were recorded in 2011 with the CMS detector and correspond to an integrated luminosity of 5 fb-1. The Z(ll) + b-jets cross sections (where ll = [mu][mu] or ee) are measured separately for a Z boson produced with exactly one b jet and with at least two b jets. In addition, a cross section ratio is extracted for a Z boson produced with at least one b jet, relative to a Z boson produced with at least one jet. The measured cross sections are compared to various theoretical predictions, and the data favour the predictions in the five-flavour scheme, where b quarks are assumed massless. The kinematic properties of the reconstructed particles are compared with the predictions from the MadGraph event generator using the pythia parton shower simulation.

Measurement of the $t\bar{t}$ Production Cross Section Using Events with One Lepton and at Least One Jet in Pp Collisions at $\sqrt{s}$

Measurement of the $t\bar{t}$ Production Cross Section Using Events with One Lepton and at Least One Jet in Pp Collisions at $\sqrt{s}$
Author :
Publisher :
Total Pages :
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ISBN-10 : OCLC:986176912
ISBN-13 :
Rating : 4/5 (12 Downloads)

Synopsis Measurement of the $t\bar{t}$ Production Cross Section Using Events with One Lepton and at Least One Jet in Pp Collisions at $\sqrt{s}$ by :

A measurement of the $\mathrm{ t \bar{t} }$ production cross section at $\sqrt{s}=$ 13 TeV is presented using proton-proton collisions, corresponding to an integrated luminosity of 2.3 fb$^{-1}$, collected with the CMS detector at the LHC. Final states with one isolated charged lepton (electron or muon) and at least one jet are selected and categorized according to the accompanying jet multiplicity. From a likelihood fit to the invariant mass distribution of the isolated lepton and a jet identified as coming from the hadronization of a bottom quark, the cross section is measured to be $\sigma(\mathrm{ t \bar{t} })=$ 835 $\pm$ 3 (stat) $\pm$ 23 (syst) $\pm$ 23 (lumi) pb, in agreement with the standard model prediction. Using the expected dependence of the cross section on the pole mass of the top quark ($m_{\mathrm{ t }}$), the value of $m_{\mathrm{ t }}$ is found to be 172.7$^{+2.4}_{-2.7}$ GeV.