HEPData Search

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Measurement of the top quark mass and t anti-t production cross-section from dilepton events at the collider detector at Fermilab

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.

Phys.Rev.Lett. 80 (1998) 2779-2784, 1998.

Inspire Record 449926 DOI 10.17182/hepdata.42173

We present an analysis of dilepton events originating from top-antitop production in proton-antiproton collisions at sqrt{s}=1.8 TeV at the Fermilab Tevatron Collider. The sample corresponds to an integrated luminosity of 109+-7 pb^{-1}. We observe 9 candidate events, with an estimated background of 2.4+-0.5 events. We determine the mass of the top quark to be M_top = 161+-17(stat.)+-10(syst.) GeV/c^2. In addition we measure a top-antitop production cross section of 8.2+4.4-3.4 pb (where M_top = 175 GeV/c^2 has been assumed for the acceptance estimate).

1 data table

Table 1

No description provided.

Search for third generation leptoquarks in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.

Phys.Rev.Lett. 78 (1997) 2906-2911, 1997.

Inspire Record 427318 DOI 10.17182/hepdata.42235

We present the results of a search for third generation leptoquark (LQ) pairs in 110±8pb−1of p¯p collisions at s=1.8TeV recorded by the Collider Detector at Fermilab. We assume third generation leptoquarks decay to a τ lepton and a b quark with branching ratio β. We observe one candidate event, consistent with standard model background expectations. We place upper limits on σ(p¯p→LQLQ¯)̇β2 as a function of the leptoquark mass MLQ. We exclude at 95% confidence level scalar leptoquarks with MLQ<99GeV/c2, gauge vector leptoquarks with MLQ<225GeV/c2, and nongauge vector leptoquarks with MLQ<170GeV/c2 for β=1.

1 data table

Table 1

The cross sections times branching ratio. KAPPA is an 'anomalous magnetic moment' (theoretical parameter). See text for details.

Forward - backward charge asymmetry of electron pairs above the Z0 pole

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.

Phys.Rev.Lett. 77 (1996) 2616-2621, 1996.

Inspire Record 417098 DOI 10.17182/hepdata.50121

We present a measurement of the forward-backward charge asymmetry of the process pp¯→Z0/γ+X,Z0/γ→e+e− at Mee>MZ, using 110pb−1 of data at s=1.8TeV collected at the Collider Detector at Fermilab. The measured charge asymmetries are 0.43±0.10 in the invariant mass region Mee>105GeV/c2, and 0.070±0.016 in the region 75

1 data table

Table 1

The forward-backward asymmetry resuts from angular differential cross section : D(SIG)/D(COS(THETA*) = A*(1 + COS(THETA*)**2) + B*COS(THETA*), where THETA * is the emission angle of the E- relative to the quark momentum in the rest frame of the E+ E- pair.

Study of t anti-t production p anti-p collisions using total transverse energy

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.

Phys.Rev.Lett. 75 (1995) 3997, 1995.

Inspire Record 396003 DOI 10.17182/hepdata.42358

We analyze a sample of W + jet events collected with the Collider Detector at Fermilab (CDF) in ppbar collisions at sqrt(s) = 1.8 TeV to study ttbar production. We employ a simple kinematical variable "H", defined as the scalar sum of the transverse energies of the lepton, neutrino and jets. For events with a W boson and four or more jets, the shape of the "H" distribution deviates by 3.8 standard deviations from that expected from known backgrounds to ttbar production. However this distribution agrees well with a linear combination of background and ttbar events, the agreement being best for a top mass of 180 GeV/c^2.

1 data table

Table 1

A result of the study of the W + >= 4JETS data sample used in PRL 74, 2626, based on 67 pb-1 of integrated luminosity.. Different fit results due to two choices of the Q2 scale in VECBOS program (see paper).

Measurement of the isolated prompt photon cross-sections in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Apollinari, G. ; et al.

Phys.Rev.Lett. 68 (1992) 2734-2738, 1992.

Inspire Record 333081 DOI 10.17182/hepdata.19869

We present a measurement of the cross section for production of isolated prompt photons in p¯p collisions at √s =1.8 TeV. The cross section, measured as a function of transverse momentum (PT), agrees qualitatively with QCD calculations but has a steeper slope at low PT.

1 data table

Table 1

Additional normalization systematic uncertainty of 27 pct for first eleven entries, and +32 pct(-46 pct) for last four entries.

Jet fragmentation properties of anti-p p collisions at S**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.

Phys.Rev.Lett. 65 (1990) 968-971, 1990.

Inspire Record 297585 DOI 10.17182/hepdata.19919

The charged-particle fractional momentum distribution within jets, D(z), has been measured in dijet events from 1.8-TeV p¯p collisions in the Collider Detector at Fermilab. As expected from scale breaking in quantum chromodynamics, the fragmentation function D(z) falls more steeply as dijet invariant mass increases from 60 to 200 GeV/c2. The average fraction of the jet momentum carried by charged particles is 0.65±0.02(stat)±0.08(syst).

1 data table

Table 1

No description provided.

Quasielastic Nucleon and Hyperon Production by Neutrinos and Anti-neutrinos With Energies Below 30-{GeV}

The SKAT collaboration Brunner, J. ; Grabosch, H.J. ; Kaufmann, H.H. ; et al.

Z.Phys.C 45 (1990) 551, 1990.

Inspire Record 26520 DOI 10.17182/hepdata.15281

The cross sections of neutrino and antineutrino quasielastic reactions\(vn \to \mu ^ -p,\bar vp \to \mu ^ +n,\bar vp \to \mu ^ +\Lambda\) were studied in the neutrino energy range between 3 and 30 GeV. In comparison withV-A theory axial mass parameters ofMA=(1.06±0.05±0.14) GeV/c2 from neutrino andMA=(0.71±0.10±0.20) GeV/c2 from antineutrino data were found. The total cross-section for the hyperon production process can be described byMA=1.0 GeV/c2.

1 data table

Table 1

Measured Quasi-Elastic total cross section.

Two Jet Differential Cross-Section in anti-p p Collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.

Phys.Rev.Lett. 64 (1990) 157, 1990.

Inspire Record 283353 DOI 10.17182/hepdata.19998

The two-jet differential cross section d3σ(p¯p→jet 1+jet 2+X)/dEtdη1dη2, averaged over -0.6≤η1≤0.6, at √s =1.8 TeV, has been measured in the Collider Detector at Fermilab. The predictions of leading-order quantum chromodynamics for most choices of structure functions show agreement with the data.

6 data tables

Table 1

Systematic error contains all known systematic uncertainties, including the effect of uncertainties in the energy scale.

Table 2

Systematic error contains all known systematic uncertainties, including the effect of uncertainties in the energy scale.

Table 3

Systematic error contains all known systematic uncertainties, including the effect of uncertainties in the energy scale.

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A MEASUREMENT OF THE TOTAL HADRONIC CROSS-SECTION IN TAGGED gamma gamma REACTIONS

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.

Phys.Rev.D 41 (1990) 2667, 1990.

Inspire Record 281351 DOI 10.17182/hepdata.22991

We present a measurement of the total cross section for γγ→hadrons, with one photon quasireal and the other a spacelike photon of mass squared −Q2. Results are presented as a function of Q2 and the γγ center-of-mass energy W, with the Q2 range extending from 0.2 to 60 GeV2, and W in the range from 2 to 10 GeV. The data were taken with the TPC/Two-Gamma facility at the SLAC e+e− storage ring PEP, which was operated at a beam energy of 14.5 GeV. The cross section exhibits a gentle falloff with increasing W. Its Q2 dependence is shown to be well described by an incoherent sum of vector-meson and pointlike scattering over most of the observed W range. Agreement at high Q2 is improved if a minimum-pT cutoff (motivated by QCD) is imposed on the pointlike contribution.

4 data tables

Table 1

Errors are statistical only.

Table 2

Errors are statistical only.

Table 3

Errors are statistical only.

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