t anti-t production cross-section in p anti-p collisions at s**(1/2) = 1.8-TeV

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abdesselam, A. ; et al.
Phys.Rev.D 67 (2003) 012004, 2003.
Inspire Record 586609 DOI 10.17182/hepdata.54899

Results are presented on a measurement of the ttbar pair production cross section in ppbar collisions at sqrt{s} = 1.8 TeV from nine independent decay channels. The data were collected by the Dzero experiment during the 1992-1996 run of the Fermilab Tevatron Collider. A total of 80 candidate events are observed with an expected background of 38.8 +- 3.3 events. For a top quark mass of 172.1 GeV/c^2, the measured cross section is 5.69 +- 1.21 (stat) +- 1.04 (sys) pb.

1 data table

Measured top quark pair production cross section in the different channels and the various averages, including the overall average.


Z gamma production in anti-p p collisions S**(1/2) = 1.8-TeV and limits on anomalous Z Z gamma and Z gamma gamma couplings

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.D 57 (1998) R3817-R3821, 1998.
Inspire Record 465977 DOI 10.17182/hepdata.42169

We present a study of Z +gamma + X production in p-bar p collisions at sqrt{S}=1.8 TeV from 97 (87) pb^{-1} of data collected in the eegamma (mumugamma) decay channel with the D0 detector at Fermilab. The event yield and kinematic characteristics are consistent with the Standard Model predictions. We obtain limits on anomalous ZZgamma and Zgammagamma couplings for form factor scales Lambda = 500 GeV and Lambda = 750 GeV. Combining this analysis with our previous results yields 95% CL limits |h{Z}_{30}| < 0.36, |h{Z}_{40}| < 0.05, |h{gamma}_{30}| < 0.37, and |h{gamma}_{40}| < 0.05 for a form factor scale Lambda=750 GeV.

1 data table

CONST(NAME=SCALE) is the model parameter, used in the modification of the couplings as follows: h = hi0/(1 + M(gamma Z)**2/CONT(NAME=SCALE)**2)**n. See article for details.


The Inclusive jet cross-section in anti-p p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 82 (1999) 2451-2456, 1999.
Inspire Record 473457 DOI 10.17182/hepdata.42154

We have made a precise measurement of the central inclusive jet cross section at sqrt(s) = 1.8 TeV. The measurement is based on an integrated luminosity of 92 pb-1 collected at the Fermilab Tevatron pbar-p Collider with the D-Zero detector. The cross section, reported as a function of jet transverse energy (ET >= 60 GeV) in the pseudorapidity interval |eta| <= 0.5, is in good agreement with predictions from next-to-leading order quantum chromodynamics.

2 data tables

Inclusive cross section for ABS(ETARAP)<0.5. The quoted systematic (DSYS) errors do not include the luminosity uncertainty of 6.1 PCT.

Inclusive cross section for 0.1<=ABS(ETARAP)<=0.7. Data are taken from the AIP E-PAPS ftp site shown above. The quoted (DSYS) errors are the total systematic errors including the luminosity uncertainty.


Small angle J / psi production in p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 82 (1999) 35-40, 1999.
Inspire Record 473954 DOI 10.17182/hepdata.42141

This paper presents the first measurement of the inclusive J/Psi production cross section in the forward pseudorapidity region 2.5<|eta|<3.7 in ppbar collisions at sqrt(s)=1.8TeV. The results are based on 9.8 pb-1 of data collected using the D0 detector at the Fermilab Tevatron Collider. The inclusive J/Psi cross section for transverse momenta between 1 and 16 GeV/c is compared with theoretical models of charmonium production.

1 data table

Only statistical errors are shown. Cross section tines branching ratio.


The Dijet mass spectrum and a search for quark compositeness in anti-p p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 82 (1999) 2457-2462, 1999.
Inspire Record 473420 DOI 10.17182/hepdata.42143

Using the DZero detector at the 1.8 TeV pbarp Fermilab Tevatron collider, we have measured the inclusive dijet mass spectrum in the central pseudorapidity region |eta_jet| < 1.0 for dijet masses greater than 200 Gev/c^2. We have also measured the ratio of spectra sigma(|eta_jet| < 0.5)/sigma(0.5 < |eta_jet| < 1.0). The order alpha_s^3 QCD predictions are in good agreement with the data and we rule out models of quark compositeness with a contact interaction scale < 2.4 TeV at the 95% confidence level.

2 data tables

Dijet cross section for ABS(ETARAP)<1.0.

Ratio of cross sections for ABS(ETARAP) < 0.5 / 0.5 < ABS(ETARAP) < 1.0.


A search for heavy pointlike Dirac monopoles

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.Lett. 81 (1998) 524-529, 1998.
Inspire Record 468445 DOI 10.17182/hepdata.42158

We have searched for central production of a pair of photons with high transverse energies in $p\bar p$ collisions at $\sqrt{s} = 1.8$ TeV using $70 pb^{-1}$ of data collected with the D\O detector at the Fermilab Tevatron in 1994--1996. If they exist, virtual heavy pointlike Dirac monopoles could rescatter pairs of nearly real photons into this final state via a box diagram. We observe no excess of events above background, and set lower 95% C.L. limits of $610, 870, or 1580 GeV/c^2$ on the mass of a spin 0, 1/2, or 1 Dirac monopole.

1 data table

No description provided.


Measurement of the shape of the transverse momentum distribution of W bosons produced in p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.Lett. 80 (1998) 5498-5503, 1998.
Inspire Record 467749 DOI 10.17182/hepdata.42166

The shape of the transverse momentum distribution of W bosons (p_T(W)) produced in pbarp collisions at sqrt(s)= 1.8 TeV is measured with the DO detector at Fermilab. The result is compared to QCD perturbative and resummation calculations over the p_T(W) range from 0-200 GeV/c. The shape of the distribution is consistent with the theoretical prediction.

1 data table

The first error is statistical, the first systematic (DSYS) error is the uncertainty in the background and efficiencies, the second is the systematic errorin the detector modelling.


Direct measurement of the top quark mass at D\O

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, B.S. ; et al.
Phys.Rev.D 58 (1998) 052001, 1998.
Inspire Record 466578 DOI 10.17182/hepdata.42170

We determine the top quark mass m_t using t-tbar pairs produced in the D0 detector by \sqrt{s} = 1.8 TeV p-pbar collisions in a 125 pb^-1 exposure at the Fermilab Tevatron. We make a two constraint fit to m_t in t-tbar -> b W^+bbar W^- final states with one W boson decaying to q-qbar and the other to e-nu or mu-nu. Likelihood fits to the data yield m_t(l+jets) = 173.3 +- 5.6 (stat) +- 5.5 (syst) GeV/c^2. When this result is combined with an analysis of events in which both W bosons decay into leptons, we obtain m_t = 172.1 +- 5.2 (stat) +- 4.9 (syst) GeV/c^2. An alternate analysis, using three constraint fits to fixed top quark masses, gives m_t(l+jets) = 176.0 +- 7.9 (stat) +- 4.8 (syst) GeV/C^2, consistent with the above result. Studies of kinematic distributions of the top quark candidates are also presented.

1 data table

No description provided.


Search for first generation scalar leptoquark pairs in p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.Lett. 80 (1998) 2051-2056, 1998.
Inspire Record 450538 DOI 10.17182/hepdata.42159

We have searched for first generation scalar leptoquark (LQ) pairs in the enu+jets channel using ppbar collider data (integrated luminosity= 115 pb^-1) collected by the DZero experiment at the Fermilab Tevatron during 1992-96. The analysis yields no candidate events. We combine the results with those from the ee+jets and nunu+jets channels to obtain 95% confidence level (CL) upper limits on the LQ pair production cross section as a function of mass and of beta, the branching fraction to a charged lepton. Comparing with the next-to-leading order theory, we set 95% CL lower limits on the LQ mass of 225, 204, and 79 GeV/c^2 for beta=1, 1/2, and 0, respectively.

1 data table

The cross section values are extracted with the assumption that BR(LQ --> EQUARK) = 1/2.


Search for scalar leptoquark pairs decaying to electrons and jets in anti-p p collisions

The D0 collaboration Abbott, B. ; Abolins, M. ; Acharya, Bannanje Sripath ; et al.
Phys.Rev.Lett. 79 (1997) 4321-4326, 1997.
Inspire Record 446155 DOI 10.17182/hepdata.42172

We have searched for the pair production of first generation scalar leptoquarks in the eejj channel using the full data set (123 pb-1) collected with the D0 detector at the Fermilab Tevatron during 1992--1996. We observe no candidates with an expected background of approximately 0.4 events. Comparing the experimental 95% confidence level upper limit to theoretical calculations of the cross section with the assumption of a 100% branching fraction to eq, we set a lower limit on the mass of a first generation scalar leptoquark of 225 GeV/c^2. The results of this analysis rule out the interpretation of the excess of high Q^2 events at HERA as leptoquarks which decay exclusively to eq.

1 data table

No description provided.