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Production of $\pi^0$ Mesons at High $p_T$ in $\pi^-$Be and pBe Collisions at 500 GeV/c

Alverson, G. ; Baker, W.F. ; Ballocchi, G. ; et al.
Phys.Rev.D 45 (1992) R3899-R3902, 1992.
Inspire Record 318740 DOI 10.17182/hepdata.22751

We present new measurements of π0 production at high transverse momenta (pT) for π− and p interactions on Be and Cu targets at 500 GeV/c. The observed dependence of the yields as a function of pT and rapidity (y) is compared with expectations from leading-log QCD over a kinematic range in which the inclusive cross sections fall by more than 4 order of magnitude.

2 data tables
Table 1

No description provided.

Table 2

A dependence parameterized as A**POWER for both Pi- and P interactions.


Direct Photon Production at High $p_T$ in $\pi^-$Be and pBe Collisions at 500 GeV/c

Alverson, G. ; Baker, W.F. ; Ballocchi, G. ; et al.
Phys.Rev.Lett. 68 (1992) 2584-2587, 1992.
Inspire Record 318739 DOI 10.17182/hepdata.19865

We report new measurements of inclusive direct photon production at high transverse momenta (pT) for π− and p interactions on Be at 500 GeV/c. The yields as a function of pT and rapidity (y) are in good agreement with expectations from next-to-leading-log QCD calculations employing recently extracted quark and gluon structure functions.

1 data table
Table 1

No description provided.


Intranuclear cascading at ultrahigh-energy in heavy ion interactions

Jain, P.L. ; Singh, G. ; Sengupta, K. ;
Z.Phys.C 52 (1991) 465-470, 1991.
Inspire Record 316804 DOI 10.17182/hepdata.14775

Intranuclear cascading mechanism one of the important non-linear effects in high energy nucleusnucleus collisions is investigated. The data on multiplicity (ns) and pseudorapidity (η) distributions of shower particles produced by32S and16O at 200A GeV,16O at 60A GeV,28Si at 14.5A GeV and He at ≈140A GeV are presented and compared with the string model VENUS, which takes into account the cascade interactions of secondary particles. The effect of the intranuclear collisions on the distributions of <η> versus <ns> is discussed for all the beams.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Improved measurements of electroweak parameters from Z decays into fermion pairs

The ALEPH collaboration Decamp, D. ; Deschizeaux, B. ; Goy, C. ; et al.
Z.Phys.C 53 (1992) 1-20, 1992.
Inspire Record 317141 DOI 10.17182/hepdata.14857

The properties of theZ resonance are measured on the basis of 190 000Z decays into fermion pairs collected with the ALEPH detector at LEP. Assuming lepton universality,Mz=(91.182±0.009exp±0.020L∶P) GeV,ГZ=(2484±17) MeV, σhad0=(41.44±0.36) nb, andГjad/Гℓℓ=21.00±0.20. The corresponding number of light neutrino species is 2.97±0.07. The forward-back-ward asymmetry in leptonic decays is used to determine the ratio of vector to axial-vector coupling constants of leptons:gv2(MZ2)/gA2(MZ2)=0.0072±0.0027. Combining these results with ALEPH results on quark charge and\(b\bar b\) asymmetries, and τ polarization, sin2θW(MZ2). In the contex of the Minimal Standard Model, limits are placed on the top-quark mass.

7 data tables
Table 1

Statistical errors only.

Table 2

No description provided.

Table 3

No description provided.

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Search for fractional charge states in high-energy heavy fragments produced in collisions of 14.5 A-GeV Si-28 with Pb and Cu target

He, Y.D. ; Price, P.B. ;
Phys.Rev.C 44 (1991) 1672, 1991.
Inspire Record 327387 DOI 10.17182/hepdata.26081

We used nuclear track detectors to construct the trajectories of interactions and to measure with high resolution the charge of the beam and of heavy nuclear fragments produced in interactions. A null result of our search for fractional charge states in high-energy fragments with charges 8≤Z≤13 produced in collisions of 14.5A GeV Si28 nuclei with Pb and Cu targets leads us to conclude that the upper limits for the probability of production of a fragment with charge 23/3, 25/3, 26/3 28/3 29/3, 31/3 32/3, 34/3, 35/3, 37/3, or 38/3 charge unit in Pb and Cu at 90% confidence level are 1.9×10−4 and 3.9×10−4, respectively. We set a similar limit on the relative number of particle-stable fragments with 8≤Z≤14 created in the central rapidity region.

1 data table
Table 1

No description provided.


Xi-, anti-xi-, Lambda and anti-Lambda production in sulphur - tungsten interactions at 200-GeV/c per nucleon

The WA85 collaboration Abatzis, S. ; Antinori, F. ; Barnes, R.P. ; et al.
Phys.Lett.B 270 (1991) 123-127, 1991.
Inspire Record 318147 DOI 10.17182/hepdata.29306

Multi-strange baryon and antibaryon production is expected to be a useful probe in the search for quark-gluon plasma formation. We present the transverse mass distributions of negative particles, Λ' s , Λ ' s and Ξ − ' s produced in sulphur-tungsten interactions at 200 GeV/ c per nucleon and give the corrected rations Λ /Λ, Ξ − /Λ and Ξ − / Λ . Our ratio Ξ − / Λ appears to be larger than that from pp interactions.

3 data tables
Table 1

Inverse slopes for different particle production.

Table 2

Data from this and other WA85 publications.

Table 3

Data from this and other WA85 publications.


The reaction e+ e- ---> gamma gamma (gamma) at Z0 energies

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.
Phys.Lett.B 268 (1991) 296-304, 1991.
Inspire Record 317825 DOI 10.17182/hepdata.29352

The total and differential cross-sections for the reaction e + e − → γγ ( γ ) are measured at centre of mass energies around 91 GeV using an integrated luminosity of 4.7 pb −1 . The aggreement with QED prediction is good. Consequently there is no evidence for non-standard channels which would have the same experimental signature. The lower limits on the QED cuttoff parameters are Λ + > 113 GeV and Λ − > 95 GeV. An upper limit on the effective coupling between a possible excited electron and the gamma is derived. At 95% confidence level the branching ratios for Z 0 decay into π 0 γ, ηψ and γγγ are below 1.5 × 10 −4 , 2.8 × 10 −4 and 1.4 × 10 −4 respectively.

2 data tables
Table 1

Radiative effects are subtracted.

Table 2

Radiative effects subtracted.


Absolute measurement of the p+p analyzing power at 183 MeV

von Przewoski, B. ; Meyer, H.O. ; Pancella, P.V. ; et al.
Phys.Rev.C 44 (1991) 44-49, 1991.
Inspire Record 327386 DOI 10.17182/hepdata.26154

The analyzing power Ay for p+p elastic scattering at θlab=8.64°±0.07° (θcms=18.1°) and at a bombarding energy of 183.1±0.4 MeV has been determined to be Ay=0.2122±0.0017. The error includes statistics, systematic uncertainties, and the uncertainty in bombarding energy and angle. This measurement represents a calibration standard for polarized beams in this energy range. The absolute scale for the measurement has been obtained by comparison with p+C elastic scattering at the same energy at an angle where Ay is very nearly unity.

1 data table
Table 1

Axis error includes +- 0.0/0.0 contribution (?////).


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<pT<160 GeV/c available from this data sample.

1 data table
Table 1

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


A Comparative study of structure function measurements from hydrogen and deuterium

Bazizi, K. ; Wimpenny, S.J. ;
UCR-DIS-91-02, 1991.
Inspire Record 317333 DOI 10.17182/hepdata.18595

None

34 data tables
Table 1

NA28 100 GeV data.

Table 2

NA28 100 GeV data.

Table 3

NA28 100 GeV data.

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