Dorfan, David E.
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Study of Heavy Flavor Production in Events With a Muon Accompanied by Jet(s) at the {CERN} Proton - Anti-proton Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Z.Phys.C 37 (1988) 489-503, 1988.
Inspire Record 250762 DOI 10.17182/hepdata.15677

We present a study of heavy flavour (charm and beauty) production using data collected with the UA1 detector at the CERN Proton-Antiproton collider at a centre-of-mass energy of 630 GeV for an integrated luminosity of 556 nb−1. This follows our earlier study ofb\(\bar b\) andc\(\bar c\) production in dimuon events and the evidence for mixing betweenB0 and\(\bar B^0 \) states. Properties of an inclusive sample of events containing a muon withpT>6 GeV/c are compared with QCD predictions for heavy flavour production, using the ISAJET Monte Carlo program. The predicted largepT muon yield from heavy flavour production and decay agrees with the data to within 30%. For events with a muon ofpT>10 GeV/c and at least one jet withET>10 GeV, we measure the ratio charm/(charm+beauty) to be (24±8±9)%. We also show that the correlations observed between the two heavy quark jets expected by flavour conservation are consistent with the mixture of lowest and higher order QCD processes. We study in detail the topological and kinematic properties of a subsample of events containing a highpT muon and one or more jets. The good agreement of the theoretical predictions with our data in a region dominated by the production of charm and beauty shows that one of the main background sources to a new heavy quark signature is well understood.

3 data tables
Table 1

No description provided.

Table 2

Numerical values supplied by K.Wacker. Muon spectrum with at least one jet with PT > 12 GeV/c.

Table 3

No description provided.


The Threshold Photoproduction of pi0 on Nucleons and on Few Nucleon Systems

Argan, P. ; Audit, G. ; Bloch, A. ; et al.
Phys.Lett.B 206 (1988) 4, 1988.
Inspire Record 251858 DOI 10.17182/hepdata.29971

The absolute value of the π 0 photoproduction cross section on the proton recently measured near threshold enables to reanalyze previous data collected on 2 H, 3 He, and 4 He relatively to the proton. Absolute cross sections are presented for these nuclei in the energy region extending up to 10 MeV above threshold. The threshold s-wave amplitudes for 2 H and 3 He thus obtained are discussed in relation with the neutron threshold amplitude E ( nπ 0 ) 0+ value.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Search for New Heavy Quarks at the CERN Proton - anti-Proton Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Z.Phys.C 37 (1988) 505-525, 1988.
Inspire Record 250763 DOI 10.17182/hepdata.15651

A search has also been made for a fourth generation, charge 1/3 quark (b'). Assuming that theb' mass is smaller than that of the top quark and that it can-not be produced inW decays, the mass limits, using the above procedures, are respectivelymb'>32 GeV/c2 andmb'>44 GeV/c2, both at 95% confidence level.

0 data tables

Version 2
High Transverse Momentum Prompt Photon Production by $\pi^-$ and $\pi^+$ on Protons at 280-{GeV}/$c$

The WA70 collaboration Bonesini, M. ; Bonvin, E. ; Boóth, P.S. L. ; et al.
Z.Phys.C 37 (1988) 535, 1988.
Inspire Record 250394 DOI 10.17182/hepdata.15649

The inclusive cross sections for prompt photon production by π− and π+ on protons have been measured with a beam momentum of 280 GeV/c using a fine grained electromagnetic calorimeter and the CERN Omega spectrometer. The transverse momentum and FeynmanxF ranges covered are 4.0<pT<7.0GeV/c and −0.45<xF<0.55 respectively. A quantitative comparison of the prompt photon cross section with next-to-leading order QCD predictions using Duke and Owens structure functions is performed.

8 data tables
Table 1

Invariant cross section. UPDATE (03 DEC 2018): systematic error of 4th bin for PT = 4.37 GEV/C corrected from 13.5 to 13.2, slight corrections to PT weighted averages (4.11 -> 4.12, 4.36 -> 4.37, 4.61 -> 4.62, 5.72 -> 5.71, 6.37 -> 6.36).

Table 2

Invariant cross section. UPDATE (03 DEC 2018): slight corrections to PT weighted averages (5.20 -> 5.21, 5.70 -> 5.71, 6.32 -> 6.34).

Table 3

PT DISTRIBUTIONS FOR SELECTED XF INTERVALS.

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Charged $K^*$ Production in $e^+ e^-$ Annihilations at 29-{GeV}

Abachi, S. ; Baringer, Philip S. ; Bylsma, B.G. ; et al.
Phys.Lett.B 199 (1987) 151-154, 1987.
Inspire Record 22433 DOI 10.17182/hepdata.6521

We report a measurement of the charged K ∗ (892) production in e + e − annihilations at 29 GeV center-of-mass energy. The 300 pb −1 data sample used for this analysis is obtained with the High Resolution Spectrometer at the SLAC storage ring PEP. The total mean multiplicity is measured to be 〈n K ∗± (892) 〉=0.62±0.045±0.04 per hadronic event. Evidence is also given for the production of a charged K 2 ∗ (1430) tensor meson.

6 data tables
Table 1

Extrapolation to full x-range using Lund model.

Table 2

Data requested from authors.

Table 3

Extrapolation to full x-range usisng fragmentation friction predicted by the Webber cluster model.

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High Transverse Momentum $\pi^0$ Production by $\pi^-$ and $\pi^+$ on Protons at 280-{GeV}/$c$

The WA70 collaboration Bonesini, M. ; Bonvin, E. ; Booth, P.S. L. ; et al.
Z.Phys.C 37 (1987) 39-50, 1987.
Inspire Record 250754 DOI 10.17182/hepdata.15679

The inclusive cross sections for π0 production by π− and π+ on protons have been measured with a beam momentum of 280 GeV/c using a fine grained electromagnetic calorimeter and the CERN Omega spectrometer. The transverse momentum and FeynmanxF ranges covered are 4.0<pT<7.0 GeV/c and −0.45<xF<0.6 respectively. The data are compared with leading order QCD calculations.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


High Transverse Momentum $J/\psi$ Production at the {CERN} Proton - Anti-proton Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Phys.Lett.B 200 (1988) 380-390, 1988.
Inspire Record 250764 DOI 10.17182/hepdata.28173

We have studied high transverse momentum J/ψ production in p p interactions at s =630 GeV . The measured cross section times branching fraction for J/ψ→μ + μ − production with p T ⩾5 GeV / c and | y |<2.0 is 7.5±0.7±1.2 nb . The event topology is used to establish that there is J/ψ production from both the direct production of c c bound states and the decay of B hadrons. The inferred yield of J/ψ from beauty decays is compatible with our estimates of beauty production in other channels.

3 data tables
Table 2

Data extracted from figure with g3data.

Table 3

Data extracted from figure with g3data.


A Study of Bhabha Scattering at {PETRA} Energies

The TASSO collaboration Braunschweig, W. ; Gerhards, R. ; Kirschfink, F.J. ; et al.
Z.Phys.C 37 (1988) 171, 1988.
Inspire Record 249557 DOI 10.17182/hepdata.45173

We report on high statistics Bhabha scattering data taken with the TASSO experiment at PETRA at center of mass energies from 12 GeV to 46.8 GeV. We present an analysis in terms of electroweak parameters of the standard model, give limits on QED cut-off parameters and look for possible signs of compositeness.

7 data tables
Table 1

Axis error includes +- 1/1 contribution (The overall uncertainty in the bin-to-bin polar acceptance due to shower corrections, trigger and reconstruction efficiencies was estimated to be less than 1% and was added in quadrature to the statistical errorsData have been corrected for qed radiative effects up to order alpha**3 (F.A.Berends, R.Kleiss, Nucl.Phys.B206(1983)61)//Weak radiative corrections have not yet been provided in a form of a Monte Carlo generator program, but are estimated to be negligible at PETRA energies (M.Bohm, A.Denner, W.Hollik, DESY-86-165)).

Table 2

Axis error includes +- 1/1 contribution (The overall uncertainty in the bin-to-bin polar acceptance due to shower corrections, trigger and reconstruction efficiencies was estimated to be less than 1% and was added in quadrature to the statistical errorsData have been corrected for qed radiative effects up to order alpha**3 (F.A.Berends, R.Kleiss, Nucl.Phys.B206(1983)61)//Weak radiative corrections have not yet been provided in a form of a Monte Carlo generator program, but are estimated to be negligible at PETRA energies (M.Bohm, A.Denner, W.Hollik, DESY-86-165)).

Table 3

Axis error includes +- 1/1 contribution (The overall uncertainty in the bin-to-bin polar acceptance due to shower corrections, trigger and reconstruction efficiencies was estimated to be less than 1% and was added in quadrature to the statistical errorsData have been corrected for qed radiative effects up to order alpha**3 (F.A.Berends, R.Kleiss, Nucl.Phys.B206(1983)61)//Weak radiative corrections have not yet been provided in a form of a Monte Carlo generator program, but are estimated to be negligible at PETRA energies (M.Bohm, A.Denner, W.Hollik, DESY-86-165)).

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Tensor Meson Excitation in the Reaction $\gamma \gamma \to K^0_S K^0_S$

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Lackas, W. ; et al.
Z.Phys.C 37 (1988) 329, 1988.
Inspire Record 250982 DOI 10.17182/hepdata.15690

In the analysis of the reactione+e−→e+e−KS0Ks0 clear evidence for exclusive γγ→f2′ resonance production is observed. The productΓγγ ·B(f2′→K\(\bar K\)) is measured to be 0.10−0.03−0.02+0.04+0.03 keV independent of ana priori assumption on the helicity structure. Our data are consistent with a pure helicity 2 contribution and we derive an upper limit for the ratioΓγγ(0)/Γγγ. The absence of events in the mass region around 1.3 GeV clearly proves destructivef2−a2 interference and allows to measure the relative phases betweenf2,a2 andf2′. Upper limits on the production of the glueball candidate statesf2(1720) andX(2230) as well as theKS0KS0-continuum are given.

1 data table
Table 1

Data read from graph.


A Precise Determination of the Electroweak Mixing Angle from Semileptonic Neutrino Scattering

The CHARM collaboration Allaby, J.V. ; Amaldi, U. ; Barbiellini, G. ; et al.
Z.Phys.C 36 (1987) 611, 1987.
Inspire Record 249672 DOI 10.17182/hepdata.15697

The cross-section ratio of neutral-current and charged-current semileptonic interactions of muon-neutrinos on isoscalar nuclei has been measured with the result:Rv=0.3093±0.0031 for hadronic energy larger than 4 GeV. From this ratio we determined the electroweak mixing angle sin2θW, wheremc is the charm-quark mass in GeV/c2. Comparison with direct measurements ofmw andmz determines the radiative shift of the intermediate boson mass Δr=0.077±0.025(exp.)±0.038(syst.), in agreement with the prediction. Assuming the validity of the electroweak standard theory we determined ϱ=0.990−0.013(mc−1.5)±0.009(exp.)±0.003(theor.).

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

STATISTICAL ERROR IN THE VALUE CITED IS REDUCING, WHEN CUT IS MORE STRINGENT?.