Hill, D.A.
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Measurement of anti-p p single diffraction dissociation at s**(1/2) = 546-GeV and 1800-GeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
Phys.Rev.D 50 (1994) 5535-5549, 1994.
Inspire Record 359393 DOI 10.17182/hepdata.42542

We report a measurement of the diffraction dissociation differential cross section d2σSD/dM2dt for p¯p→p¯X at √s =546 and 1800 GeV, M2/s<0.2 and 0≤-t≤0.4 GeV2. Our results are compared to theoretical predictions and to extrapolations from experimental results at lower energies.

1 data table
Table 1

Single diffraction dissociation cross section.


Measurement of the anti-proton proton total cross-section at s**(1/2) = 546-GeV and 1800-GeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
Phys.Rev.D 50 (1994) 5550-5561, 1994.
Inspire Record 359412 DOI 10.17182/hepdata.42528

We report a measurement of the proton-antiproton total cross section σT at c.m.s. energies √s =546 and 1800 GeV. Using the luminosity-independent method, we find σT=61.26±0.93 mb at √s =546 GeV and 80.03±2.24 mb at √s =1800 GeV. In this energy range, the ratio σel/σT increases from 0.210±0.002 to 0.246±0.004.

2 data tables
Table 1

No description provided.

Table 2

Assuming RHO = 0.15.


Measurement of the photon structure function F2 (gamma) in the reaction e+ e- ---> e+ e- + hadrons at LEP

The OPAL collaboration Akers, R. ; Alexander, G. ; Allison, John ; et al.
Z.Phys.C 61 (1994) 199-208, 1994.
Inspire Record 358863 DOI 10.17182/hepdata.48474

We present measurements of the hadronic photon structure functionF2γ(x), in twoQ2 ranges with mean values of 5.9 GeV2 and 14.7 GeV2. The data were taken by the OPAL experiment at LEP, with\(\sqrt s\) close to theZ0 mass and correspond to an integratede+e− luminosity of 44.8 pb−1. In the context of a QCD-based model we find the quark transverse momentum cutoff separating the vector meson dominance (VMD) and perturbative QCD regions to be 0.27±0.10 GeV. We confirm that there is a significant pointlike component of the photon when the probe photon hasQ2>4 GeV2. Our measurements extend to lower values ofx than any previous experiment, and no increase ofF2γ(x) is observed.

2 data tables
Table 1

Additional overall systematic error 5.9% not included.

Table 2

Additional overall systematic error 5.9% not included.


Measurement of inclusive jet cross-sections in photoproduction at HERA

The H1 collaboration Abt, I. ; Ahmed, T. ; Andreev, V. ; et al.
Phys.Lett.B 314 (1993) 436-444, 1993.
Inspire Record 356741 DOI 10.17182/hepdata.28821

The inclusive jet cross section in photoproduction has been measured as a function of transverse energy and pseudorapidity using the H 1 detector at the HERA electron-proton collider. The results are compared with leading order QCD calculations.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


A Measurement of alpha-s from jet rates at the Z0 resonance

The SLD collaboration Abe, K. ; Abt, I. ; Acton, P.D. ; et al.
Phys.Rev.Lett. 71 (1993) 2528-2532, 1993.
Inspire Record 356912 DOI 10.17182/hepdata.19724

We have determined the strong coupling αs from measurements of jet rates in hadronic decays of Z0 bosons collected by the SLD experiment at SLAC. Using six collinear and infrared safe jet algorithms we compared our data with the predictions of QCD calculated up to second order in perturbation theory, and also with resummed calculations. We find αs(MZ2)=0.118±0.002(stat)±0.003(syst)±0.010(theory), where the dominant uncertainty is from uncalculated higher order contributions.

1 data table
Table 1

The second systematic error comes from the theoretical uncertainties.


Search for quark compositeness, axigluons and heavy particles using the dijet invariant mass spectrum observed in p anti-p collisions

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Akimoto, H. ; et al.
Phys.Rev.Lett. 71 (1993) 2542-2546, 1993.
Inspire Record 356676 DOI 10.17182/hepdata.19713

The dijet invariant mass distribution has been measured in the region between 140 and 1000 GeV/c2, in 1.8 TeV p p¯ collisions. Data collected with the Collider Detector at Fermilab show agreement with QCD calculations. A limit on quark compositeness of Λc>1.3 TeV is obtained. Axigluons with masses between 240 and 640 GeV/c2 are excluded at 95% C.L. if we assume ten open decay channels. Model-independent limits on the production of heavy particles decaying into two jets are also presented.

1 data table
Table 1

No description provided.


Measurement of bottom quark production in 1.8-TeV p anti-p collisions using semileptonic decay muons

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
Phys.Rev.Lett. 71 (1993) 2396-2400, 1993.
Inspire Record 356237 DOI 10.17182/hepdata.19723

We present a measurement of the b-quark cross section in 1.8 TeV p-p¯ collisions recorded with the Collider Detector at Fermilab using muonic b-quark decays. In the central rapidity region (‖yb‖<1.0), the cross section is 295±21±75 nb (59±14±15 nb) for pTb>21 GeV/c (29 GeV/c). Comparisons are made to previous measurements and next-to-leading order QCD calculations.

1 data table
Table 1

No description provided.


Measurement of Drell-Yan electron and muon pair differential cross-sections in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.
Phys.Rev.D 49 (1994) R1-R6, 1994.
Inspire Record 355927 DOI 10.17182/hepdata.42543

We measure the Drell-Yan differential cross section d2σdMdy||y|<1 over the mass range 11<M<150 GeV/c2 using dielectron and dimuon data from p¯p collisions at a center-of-mass energy of s=1.8 TeV. Our results show the 1M3 dependence that is expected from the naive Drell-Yan model. In comparison to the predictions of recent QCD calculations we find our data favor those parton distribution functions with the largest quark contributions in the x interval 0.006 to 0.03.

3 data tables
Table 1

Dielectron differential cross section.

Table 2

Dimuon differential cross section.

Table 3

Drell-Yan differential cross section for combined dielectron and dimuon data. Error includes both statistics and systematics.


Mass dependence of pion production in heavy ion collisions near, but below threshold

Miller, J. ; Krebs, G.F. ; Panetta, J. ; et al.
Phys.Lett.B 314 (1993) 7-12, 1993.
Inspire Record 357754 DOI 10.17182/hepdata.38101

We have measured the inclusive cross section for production of negative pions near mid-rapidity in 20 Ne + NaF , 139 La + 139 La and 197 Au + 197 Au collisions at E = 183 and 236 MeV/u. Au + Au is the heaviest system from which subthreshold pion production has been measured to date. The dependence of the pion cross section on pion energy, beam energy and associated charged particle multiplicity is consistent with previous results both above and below threshold. The dependence of the cross section on the mass of the colliding system varies only slightly as the beam energy is reduced below threshold, in contrast to some previous measurements. Comparison with theory suggests that at these energies the pion production process is still dominated by nucleon-nucleon collisions.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


The Forward - backward asymmetry of e+ e- ---> b anti-b and e+ e- ---> c anti-c using leptons in hadronic Z0 decays

The OPAL collaboration Acton, P.D. ; Akers, R. ; Alexander, G. ; et al.
Z.Phys.C 60 (1993) 19-36, 1993.
Inspire Record 356097 DOI 10.17182/hepdata.14320

The forward-backward asymmetries of$$e^ + e^ - \to Z^0 \to b\bar b and e^ + e^ - \to Z^0 \to c\bar c$$

5 data tables
Table 1

Measurement of the asymmetry in b-quark production on the Z0 peak using a two parameter fit, neglecting the effects of B0-BBAR0 mixing.

Table 2

Measurement of the asymmetry in b-quark production on the Z0 peak using a two parameter fit and correcting for B0-BBAR0 mixing. The second systematic error is due to the uncertainty of the mixing factor.

Table 3

Measurement of the asymmetry in c-quark production on the Z0 peak using a two parameter fit.

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