HEPData Search

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Search for second generation leptoquark pairs 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. 84 (2000) 2088-2093, 2000.

Inspire Record 508772 DOI 10.17182/hepdata.42087

We have searched for second generation leptoquark (LQ) pairs in the \mu\mu+jets channel using 94+-5 pb^{-1} of pbar-p collider data collected by the D0 experiment at the Fermilab Tevatron during 1993-1996. No evidence for a signal is observed. These results are combined with those from the \mu\nu+jets and \nu\nu+jets channels to obtain 95% confidence level (C.L.) upper limits on the LQ pair production cross section as a function of mass and $beta, the branching fraction of a LQ decay into a charged lepton and a quark. Lower limits of 200(180) GeV/c^2 for \beta=1(1/2) are set at the 95% C.L. on the mass of scalar LQ. Mass limits are also set on vector leptoquarks as a function of \beta.

1 data table

Table 1

No description provided.

Small angle muon and bottom quark 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. 84 (2000) 5478-5483, 2000.

Inspire Record 503949 DOI 10.17182/hepdata.42072

This Letter describes a measurement of the muon cross section originating from b quark decay in the forward rapidity range 2.4 < y(mu) < 3.2 in pbarp collisions at sqrt(s) = 1.8 TeV. The data used in this analysis were collected by the D0 experiment at the Fermilab Tevatron. We find that NLO QCD calculations underestimate b quark production by a factor of four in the forward rapidity region. A cross section measurement using muon+jet data has been included in this version of the paper.

3 data tables

Table 1

The forward muon cross section (per unit rapidity).

Table 2

The cross section for muons originating from b-quark decay.

Table 3

Integrated cross sections for muons originating from b-quark decay. The statistical and systematic errors are added in quadrature.

rivet Analysis
The b anti-b production cross-section and angular correlations in p anti-p collisions at S**(1/2) = 1.8-TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.

Phys.Lett.B 487 (2000) 264-272, 2000.

Inspire Record 499943 DOI 10.17182/hepdata.42088

We present measurements of the b-bbar production cross section and angular correlations using the D0 detector at the Fermilab Tevatron p-pbar Collider operating at sqrt(s) = 1.8 TeV. The b quark production cross section for |y(b)|<1.0 and p_T(b)>6 GeV/c is extracted from single muon and dimuon data samples. The results agree in shape with the next-to-leading order QCD calculation of heavy flavor production but are greater than the central values of these predictions. The angular correlations between b and bbar quarks, measured from the azimuthal opening angle between their decay muons, also agree in shape with the next-to-leading order QCD prediction.

3 data tables

Table 1

No description provided.

Table 2

The errors are combinations of statistical and systematic uncertainties.

Table 3

The distribution of MU+ MU- azimuthal angle difference.

Study of D*+ and search for D**0 production by neutrinos in BEBC

The Big Bubble Chamber Neutrino collaboration Asratvan, A.E. ; Aderholz, M. ; Ammosov, V.V. ; et al.

Z.Phys.C 68 (1995) 43-46, 1995.

Inspire Record 395454 DOI 10.17182/hepdata.47928

Data from BEBC experiments are combined to provide large statistics for neutrino interactions. ChargedD* mesons are produced in (1.22±0.25)% of neutrino and (1.01±0.31)% of antineutrino charged current interactions. The mean fraction of the hadronic laboratory energy taken by theD*+ in these events is 0.59±0.03±0.08. Less than 18% of all chargedD* mesons from (anti)neutrino interactions are found to be daughters ofD**0 (at the 90% confidence level).

4 data tables

Table 1

Mean fractional hadronic energy carried by the D*+- in the laboratory system.

Table 2

Mean value of the Bjorken scaling variable X.

Table 3

Rate of charged D* meson production per charged current neutrino interaction.

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Observation of D(s)** (2536) meson production by neutrinos in BEBC

The Big Bubble Chamber Neutrino collaboration Asratyan, A.E. ; Aderholz, M. ; Ammosov, V.V. ; et al.

Z.Phys.C 61 (1994) 563-566, 1994.

Inspire Record 363214 DOI 10.17182/hepdata.14264

Neutrino interactions in BEBC produce theDS** (2536) charmed strange meson. The mass of this state is 2534.2±1.2 MeV. The production rate is 0.011±0.005 per neutrino charged current interaction at a mean neutrino energy of 61 GeV. An earlier claim for another$c\bar s$ bound state near 2565 MeV, produced in neutrino interactions, is not supported.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Dimuon Production by Neutrinos in the {Fermilab} 15-ft. Bubble Chamber at the Tevatron

The E632 collaboration Jain, V. ; Harris, F.A. ; Aderholz, M. ; et al.

Phys.Rev.D 41 (1990) 2057, 1990.

Inspire Record 281906 DOI 10.17182/hepdata.22938

The Fermilab 15-ft bubble chamber has been exposed to a quadrupole triplet neutrino beam produced at the Tevatron. The ratio of ν to ν¯ in the beam is approximately 2.5. The mean event energy for ν-induced charged-current events is 150 GeV, and for ν¯-induced charged-current events it is 110 GeV. A total of 64 dimuon candidates (1 μ+μ+, 52 μ−μ+ and μ+μ−, and 11 μ−μ−) is observed in the data sample of approximately 13 300 charged-current events. The number and properties of the μ−μ− and μ+μ+ candidates are consistent with their being produced by background processes, the important sources being π and K decay and punchthrough. The 90%-C.L. upper limit for μ−μ−/μ− for muon momenta above 4 GeV/c is 1.2×10−3, and for momenta above 9 GeV/c this limit is 1.1×10−3. The opposite-sign-dimuon–to–single-muon ratio is (0.62±0.13)% for muon momenta above 4 GeV/c. There are eight neutral strange particles in the opposite-sign sample, leading to a rate per dimuon event of 0.65±0.29. The opposite-sign-dimuon sample is consistent with the hypothesis of charm production and decay.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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