Baumann, Dagmar
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A Measurement of the Inclusive $\pi^0$ and $\eta$ Production Cross-sections at High $p_T$ in $p \bar{p}$ and $p p$ Collisions at $\sqrt{s}=24$.3-{GeV}

The UA6 & CERN-Lausanne-Michigan-Rockefeller collaborations Antille, J. ; Baumann, S. ; Bernasconi, A. ; et al.
Phys.Lett.B 194 (1987) 568, 1987.
Inspire Record 247579 DOI 10.17182/hepdata.30119

Inclusive π 0 and η production at large transverse momentum were studied in both p̄p and pp interactions at √ s = 24.3 GeV. The experiment was performed using an internal molecular hydrogen gas jet target in the CERN SPS collider. No significant differences between production in p̄p and pp were observed in the transverse momentum range 2.5 < P T < 5.1 GeV/ c .

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Quasi-Free Compton Scattering by the Neutron

Rose, K.W. ; Zurmuhl, B. ; Rullhusen, P. ; et al.
Nucl.Phys.A 514 (1990) 621-648, 1990.
Inspire Record 313708 DOI 10.17182/hepdata.36855

Using non-tagged bremsstrahlung produced by a 130 MeV–20 μA c.w. electron beam of MAMI A quasi-free Compton scattering by the neutron was investigated via the 2 H( γ , γ 'n) 1 H reaction for lab scattering angles of θ γ = 90° and 135°. The energy spectrum and angular distribution of recoiling neutrons were measured via time of flight and a plastic-scintillator hodoscope, respectively. Double-differential cross sections for quasi-free scattering by the neutron were determined on an absolute scale by normalizing to the Compton cross section of the proton. By comparing the experimental double-differential cross sections with predictions the electric polarizability of the neutron was determined, leading to α n = (10.7 −10.7 +3.3 ) × 10 −4 fm 3 . Thus, the upper limit of α n is further reduced as compared to our previous result, but the lower limit is still consistent with zero.

1 data table
Table 1

No description provided.


A Determination of sin**2-theta from the forward - backward asymmetry in p anti-p ---> Z0 X ---> e+ e- X interactions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 67 (1991) 1502-1506, 1991.
Inspire Record 317764 DOI 10.17182/hepdata.19899

An analysis of the forward-backward asymmetry in Z0 decays using data from the Collider Detector at Fermilab at √s =1.8 TeV yields AFB=[5.2±5.9(stat)±0.4(syst)]% and sin2θ¯W =0.228−0.015+0.017(stat)±0.002(syst).

2 data tables
Table 1

Asymmetry after background and QCD corrections.

Table 2

SIN2TW derived from asymmetry measurement fully corrected for background and radiative corrections.


Measurement of the Z (p(T)) distribution 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. 67 (1991) 2937-2941, 1991.
Inspire Record 322634 DOI 10.17182/hepdata.19888

We have measured the Z-boson production differential cross section as a function of transverse momentum using Z→ee and Z→μμ decays in p¯p collision at √s =1.8 TeV with the Collider Detector at Fermilab. Comparison with standard-model predictions shows good agreement over the range 0

1 data table
Table 1

Errors are systematic and statistical combined, and are correlated bin to bin due to the correction for resolution smearing.


Inclusive jet cross-section 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) 1104-1108, 1992.
Inspire Record 319237 DOI 10.17182/hepdata.19883

We present a measurement of the inclusive jet cross section in p¯p collisions at √s =1.8 TeV at the Fermilab Tevatron using the Collider Detector at Fermilab. Good agreement is seen with the predictions of recent next-to-leading-order [O(αs3)] QCD predictions. The dependence of the cross section on clustering cone size is reported for the first time. An improved limit on Λc, a term characterizing possible quark substructure, is set at 1.4 TeV (95% C.L.).

1 data table
Table 1

Data are averaged over the pseudorapidity interval 0.1 to 0.7.


Lepton asymmetry in W decays from 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) 1458-1462, 1992.
Inspire Record 323033 DOI 10.17182/hepdata.19880

The charge asymmetry of leptons from W-boson decay has been measured using p¯p data from the Collider Detector at Fermilab at √s =1.8 TeV. The observed asymmetry is well described by most of the available parton distributions.

3 data tables
Table 1

Electrons in the central region.

Table 2

Muons in the central region.

Table 3

Plug electrons.


Measurement of the ratio sigma B (W ---> tau-neutrino) / sigma B (W ---> e neutrino), in p anti-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) 3398-3402, 1992.
Inspire Record 324086 DOI 10.17182/hepdata.19851

We have observed over 102 events of the type W→τν followed by τ→ hadrons, where the taus are identified by their decay into one or three charged particles. We measure the cross section times branching ratio for pp¯→W→τν and compare it to the value for W→eν to directly measure the ratio of weak coupling constants gτ/ge. We find gτ/ge=0.97±0.07, consistent with lepton universality.

3 data tables
Table 1

Results from the missing ET trigger.

Table 2

Results from the tau trigger.

Table 3

Results from the combined ET trigger.


A Measurement of the B meson and b quark cross-sections at s**(1/2) = 1.8-TeV using the exclusive decay B+- ---> J / psi K+-

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 68 (1992) 3403-3407, 1992.
Inspire Record 333080 DOI 10.17182/hepdata.19852

This letter reports the full reconstruction of B mesons through the decay chain B±→J/ψ K±, J/ψ→μ+μ−, using data obtained at the Collider Detector at Fermilab in p¯p collisions at √s =1.8 TeV. This exclusive sample, the first observed at a hadron collider, is then used to measure the B-meson cross section, from which we extract the b-quark cross section. We obtain σ=2.8±0.9 (stat) ±1.1(syst) μb for B− mesons with PT>9.0 GeV/c and rapidity ‖y‖<1.0. We obtain σ=6.1±1.9(stat) ±2.4(syst) μb, for b quarks with transverse momentum PT>11.5 GeV/c and rapidity ‖y‖<1.0.

2 data tables
Table 1

B-meson cross section.

Table 2

B-quark cross section.


Measurement of B0 anti-B0 mixing at the Fermilab Tevatron collider

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 67 (1991) 3351-3355, 1991.
Inspire Record 332810 DOI 10.17182/hepdata.19881

The B0 B¯ 0 average mixing parameter χ has been extracted from eμ and ee events produced in pp¯ collisions at √s =1.8 TeV. In a sample of 900 eμ events, the like-sign to opposite-sign charge ratio R is measured to be 0.556±0.048(stat)−0.042+0.035(syst). In the absence of mixing, the expected value of R would be 0.23±0.06. The corresponding number for 212 ee events is 0.573±0.116(stat)±0.047(syst) with an expected nonmixing value of 0.24±0.07. The observed excess in R leads to a combined determination of χ=0.176±0.031(stat+syst) ±0.032 (model), where the last uncertainty is due to Monte Carlo modeling.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


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.