Evangelista, C.
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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 ???.


rivet Analysis
Measurement of $K^\pm$ and $K^0$ Inclusive Rates in $e^+ e^-$ Annihilation at 29-{GeV}

Schellman, H. ; Trilling, G. ; Abrams, G.S. ; et al.
Phys.Rev.D 31 (1985) 3013, 1985.
Inspire Record 207785 DOI 10.17182/hepdata.23580

We have measured the K0+K¯ 0 inclusive cross section in e+e− annihilation at 29 GeV with the Mark II detector SLAC PEP. We find 1.27±0.03±0.15 K0+K¯ 0 per hadronic event. We have also used time-of-flight particle identification to measure the K± rate over the momentum range 300–900 MeV/c.

4 data tables
Table 1

Extrapolated to full momentum range by Monte-Carlo.

Table 2

Statistical errors only.

Table 3

No description provided.

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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.


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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Forward Particle Production in $\pi^- p$ and $K^- p$ Collisions at 58-{GeV}/$c$ and Comparison With Quark Models

The ACCMOR collaboration Pauß, F. ; Gonzalez-Arroyo, A. ; Ochs, W. ; et al.
Z.Phys.C 27 (1985) 211, 1985.
Inspire Record 206988 DOI 10.17182/hepdata.16120

We present single inclusive π±, π0 andK± spectra in the forward fragmentation region (x>0.2,pT<1.5 GeV/c) as well as correlations between two charged particles. The data were recorded in an unseparated negative hadron beam at the CERN SPS using a large acceptance forward spectrometer. Our maasurements are compared in detail with several models which emphasise the role of the beam valence quarks in this production process. The connection to measurements at largepT is also investigated.

3 data tables
Table 1

ERRORS INCLUDE SYSTEMATIC ERRORS BUT NOT OVERALL NORMALISATION UNCERTAINTY OF 8PCT.

Table 2

ERRORS INCLUDE SYSTEMATIC ERRORS BUT NOT OVERALL NORMALISATION UNCERTAINTY OF 8PCT.

Table 3

ERRORS INCLUDE SYSTEMATIC ERRORS BUT NOT OVERALL NORMALISATION UNCERTAINTY OF 8PCT.


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.


Elastic Scattering of Charged Mesons, Anti-protons and Protons on Protons at Incident Momenta of 20-{GeV}/$c$, 30-{GeV}/$c$ and 50-{GeV}/$c$ in the Momentum Transfer Range $0.5-{\rm GeV}/c^2 < -t < 8-{\rm GeV}/c^2$

The Annecy(LAPP)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Asad, Z. ; Baglin, C. ; Bock, R. ; et al.
Nucl.Phys.B 255 (1985) 273-327, 1985.
Inspire Record 206292 DOI 10.17182/hepdata.33789

Results are presented from experiment WA7 at the CERN SPS, which has measured the elastic differential cross sections of π ± p, K ± p, p p and pp at incident momen ta of 20, 30 and 50 GeV/ c . The measurements cover the momentum transfer range 0.5 < | t | < 8 (GeV/ c ) 2 , corresponding to c.m. scattering angles between 10° and 50°. The experimental set-up, trigger logic and data analysis are described. The experimental results are compared with existing meson-proton and nucleon-proton data at lower and higher energies covering the medium- and large-| t | region. Some prominent models and their predictions for elastic scattering at WA7 energies and beyond are reviewed, with emphasis on geometrical scaling, factorizing eikonal models, lowest-order QCD and other dynamical exchange-type models. Results for p p two-body annihilation into π − π + and K − K + at 30 and 50 GeV/ c , obtained in parallel with the elastic p p data, are also presented.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
INCLUSIVE gamma AND pi0 PRODUCTION CROSS-SECTIONS AND ENERGY FRACTIONS IN e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Bakken, J.A. ; et al.
Z.Phys.C 27 (1985) 187, 1985.
Inspire Record 205868 DOI 10.17182/hepdata.16101

Inclusive production cross sections for photons and π0's ine+e− annihilation at a center of mass energy of 29 GeV have been measured. The π0 production spectrum agrees with a corresponding measurement for π±. The ratio of the π0 inclusive rate to the average for π± is 0.92±0.14. The fractions of the total energy carried by photons and π0's are 0.244±0.016 and 0.217±0.033, respectively. The fraction of total energy carried by all stable hadrons, prompt leptons and photons is determined to be 0.938±0.045, leaving 0.062±0.045 for neutrinos.

2 data tables
Table 1

No description provided.

Table 2

No description provided.