Nakamura, K.
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A MEASUREMENT OF THE DIFFERENCE BETWEEN THE SINGLE NUCLEON CROSS-SECTIONS FOR j / psi MUOPRODUCTION IN IRON AND IN H-2, D-2 TARGETS

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 152 (1985) 433-438, 1985.
Inspire Record 207459 DOI 10.17182/hepdata.30432

The cross sections for J ψ production have been measured in interactions of 280 GeV μ + on hydrogen and deuterium (H, D) and also in interactions of 250 GeV μ + on iron. The single-nucleon cross sections in iron are found to be larger than those in H, D. The mean ratio of the iron to H, D photoproduction cross sections in the range 60 < v < 200 GeV is 1.45 ±0.12 (statistical) ±0.22 (systematic error). Within the framework of the photon-gluon fusion model, this indicates that the gluon density per nucleon is ∼45% larger in iron than in H, D in the range 0.026 < x < 0.085, on a mass scale Q 2 eff ∼M 2 J ψ .

3 data tables
Table 1

First table is from combined H and DEUT data at 280 Gev. Second table is from FE data at 250 Gev.

Table 2

First table is from combined H and DEUT data at 280 Gev. Second table is from FE data at 250 Gev.

Table 3

THIS TABLE IS THE RATIO OF THE EFFECTIVE GLUON DISTRIBUTIONS IN IRON AND HYDROGEN(DEUTERIUM) ASSUMING THAT PHOTON-GLUON FUSION IS THE RELEVANT MECHANISM FOR J/PSI PRODUCTION.


Polarization of Charmed $\Lambda(c$)+ Baryons Produced in Neutron - Carbon Interactions

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
Yad.Fiz. 43 (1986) 619-623, 1986.
Inspire Record 209855 DOI 10.17182/hepdata.39660

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


A Measurement of Strong Coupling Constant $\alpha_s$ to Second Order for 14-{GeV} $\le \sqrt{s} \le$ 46.78-{GeV}

The MARK-J collaboration Adeva, B. ; Becker, U. ; Becker-Szendy, R. ; et al.
Phys.Rev.Lett. 54 (1985) 1750, 1985.
Inspire Record 208007 DOI 10.17182/hepdata.20386

Using the Mark-J detector at the high-energy e+e− collider PETRA, we compare the data from hadron production with the complete second-order QCD calculation over the energy region 22 to 46.78 GeV. We determine the QCD parameter Λ=100±30−45+60 MeV which yields the strong-coupling constant αs=0.12±0.02 for s=44 GeV.

2 data tables
Table 1

No description provided.

Table 2

Axis error includes +- 0.0/0.0 contribution (DUE TO FRAGMENTATION MODEL).


Tests of the Standard Model With Lepton Pair Production in $e^+ e^-$ Reactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Z.Phys.C 27 (1985) 341, 1985.
Inspire Record 207950 DOI 10.17182/hepdata.1917

The differential cross section of the reactione+e−→e+e− at a c.m. energy of 34.7 GeV has been measured. The result, together with our previously measurede+e−→α+α− data, are compared with the standard model predictions. We obtain for the weak neutral current couplings the valuesgv2=0.09×0.06,ga2=0.38×0.08. A fit of the Weinberg mixing angle gives the valuegv2=0.09×0.06,ga2=0.038×0.08. The data are also used to set limits on possible deviations from the pointlike structure of leptons. An upper limit for thee+e− coupling to a heavy spin 0 boson is also given.

3 data tables
Table 1

Fully corrected results for Bhabha scattering.

Table 2

The differential cross section for Bhabha scattering.

Table 3

??? CONSTANTS ???.


Search for Monochromatic Pion Emission in $\bar{p} p$ Annihilation From Atomic $p$ States

The ASTERIX collaboration Ahmad, S. ; Amsler, Claude ; Armenteros, R. ; et al.
Phys.Lett.B 152 (1985) 135-139, 1985.
Inspire Record 207457 DOI 10.17182/hepdata.49644

Narrow states observable through the emission of monoenergetic charged pions have been searched for in p p annihilation at rest in a gaseous hydrogen target where annihilation from atomic angular momentum L = 1 states dominates. No structure is observed. The 5σ upper limit for the production of narrow states in the mass range 1100–1670 MeV is 2 × 10 −3 of all annihilations.

1 data table
Table 1

X means a narrow state.


Precise Measurements of Proton - Anti-proton and Proton Proton Total Cross-sections at the {CERN} Intersecting Storage Rings

Carboni, G. ; Lloyd Owen, D. ; Potter, K. ; et al.
Nucl.Phys.B 254 (1985) 697-736, 1985.
Inspire Record 207680 DOI 10.17182/hepdata.33833

A detailed account is given of high-precision measurements of the total hadronic cross sections of proton-antiproton and proton-proton interactions at centre-of-mass energies of 30.6, 52.8 and 62.7 GeV. The experiment was performed at the CERN Intersecting Storage Rings (ISR) using the total interaction-rate method, in which additive correction terms for trigger losses were held to less than 6% of the final result. An experimental determination of the vertical beam-displacement scale permitted luminosity-monitor calibrations to be made with high intrinsic accuracy. The overall precision (systematic and statistical errors combined) achieved in the total cross sections was ± 1.1% for proton-antiproton reactions and 0.7% for proton-proton reactions. In the proton-proton case the measurement was the most precise such measurement made at the ISR.

3 data tables
Table 1

No description provided.

Table 2

ERRORS CONTAIN BOTH STATISTICS AND SYSTEMATICS.

Table 3

ERRORS CONTAIN POINT-TO-POINT AND THE ERROR-INDEPENDANT ERRORS.


A MEASUREMENT OF ALPHA-ALPHA ELASTIC SCATTERING AT THE CERN ISR

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 152 (1985) 140-144, 1985.
Inspire Record 206315 DOI 10.17182/hepdata.30430

We present measurements of the αα elastic scattering differential cross section at √ s = 126 GeV in the range 0.05 ⩽ ‖ t ‖

3 data tables
Table 1

ERRORS ARE STATISTICAL ONLY.

Table 2

EXPONENTIAL FIT TO CROSS SECTION BELOW T = 0.075 GEV**2.

Table 3

OPTICAL THEOREM CALCULATION OF THE TOTAL CROSS SECTION ASSUMING RHO IS ZERO.


Studies of Quark and Diquark Fragmentation Into Identified Hadrons in Deep Inelastic Muon - Proton Scattering

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.
Phys.Lett.B 150 (1985) 458, 1985.
Inspire Record 206297 DOI 10.17182/hepdata.30438

None

19 data tables
Table 1

Backward Multiplicity.

Table 2

Forward Multiplicity.

Table 3

No description provided.

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MEASUREMENTS OF THE STRUCTURE FUNCTIONS F2 (x, Q**2) FROM neutrino p AND ANTI-NEUTRINO p INTERACTIONS

The WA21 collaboration Grassler, H. ; Lanske, D. ; Schulte, R. ; et al.
OXFORD NP-79/84, 1984.
Inspire Record 15788 DOI 10.17182/hepdata.1180

None

2 data tables
Table 1

NORMALISATION UNCERTAINTY IS 7 PCT.

Table 2

NORMALISATION UNCERTAINTY IS 7 PCT.


rivet Analysis
Precision Measurement of the Total Cross-section for $e^+ e^- \to$ Hadrons at a Center-of-mass Energy of 29-{GeV}

Fernandez, E. ; Ford, William T. ; Qi, N. ; et al.
Phys.Rev.D 31 (1985) 1537, 1985.
Inspire Record 206052 DOI 10.17182/hepdata.4048

We report a high-precision measurement of the ratio R of the total cross section for e+e−→hadrons to that for e+e−→μ+μ−, at a center-of-mass energy of 29.0 GeV using the MAC detector. The result is R=3.96±0.09. This value of R is used to determine a value of the strong coupling constant αs of 0.23±0.06, nearly independent of fragmentation models. Two different analysis methods having quite different event-selection criteria have been used and the results are in agreement. Particular attention has been given to the study of systematic errors. New higher-order QED calculations are used for the luminosity determination and the acceptance for hadrons.

2 data tables
Table 1

No description provided.

Table 2

No description provided.