Date

Multiplicity Distributions in $\alpha \alpha$ and $\alpha p$ Collisions at the {CERN} {ISR}

The CERN-Heidelberg-Lund collaboration Bell, W. ; Braune, K. ; Claesson, G. ; et al.
Phys.Lett.B 128 (1983) 349-353, 1983.
Inspire Record 190332 DOI 10.17182/hepdata.30673

The multiplicities of charged secondaries from inelastic αp and αα collisions have been measured using the Split-Field Magnet detector at the CERN Intersecting Storage Rings. Corrected multiplicity distributions for αα and αp interactions are compared with those for pp interactions and with theoretical predictions.

2 data tables

No description provided.

No description provided.


Elastic and total cross-section measurement at the CERN proton-antiproton collider

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.
Phys.Lett.B 128 (1983) 336, 1983.
Inspire Record 190339 DOI 10.17182/hepdata.30668

Proton-antiproton elastic scattering at CM energy 540 GeV has been studied in the t -range 0.04 < − t < 0.45 GeV 2 . The data are well fitted by the form exp ( bt ) with b = 17.1 ± 1.0 GeV −2 for | t | = 0.04 − 0.18 GeV su 2 and b = 13.7 ± 0.2 ± 0.2 GeV −2 for | t | = 0.21−0.45 GeV 2 . A luminosity measurement combined with the optical theorem gives σ tot = 67.6 ± 5.9 ± 2.7 mb and σ e1 / σ tot = 0.209 ± 0.018 ± 0.008.

3 data tables

No description provided.

No description provided.

ELASTIC RATIO ASSUMES RHO=0.


The Dominance of Jets at Large Transverse Energy in a Full Azimuth Hadron Calorimeter at {ISR} Energies

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 128 (1983) 354-360, 1983.
Inspire Record 190652 DOI 10.17182/hepdata.30701

Events with a large transverse energy in a calorimeter with full azimuthal coverage and | y | < 0.9 have been investigated in pp collisions at √ s = 30, 45, and 63 GeV. A striking change in the event structure, corresponding to a clear emergence of high- p T jets, is observed at √ s = 63 and 45 GeV in the region between 25 and 35 GeV in transverse energy. At √ s = 30 GeV, the data extend to E T ∼ 20 GeV, but no such change in the event structure is observed.

3 data tables

No description provided.

No description provided.

No description provided.


Proton - Anti-proton Annihilations at Rest Into $\pi^0 \omega$, $\pi^0 \eta$, $\pi^0 \gamma$, $\pi^0 \pi^0$, and $\pi^0 \eta^\prime$

Backenstoss, G. ; Hasinoff, M. ; Pavlopoulos, P. ; et al.
Nucl.Phys.B 228 (1983) 424-438, 1983.
Inspire Record 189897 DOI 10.17182/hepdata.33919

Proton-antiproton annihilations at rest in liquid hydrogen were investigated through the inclusive γ spectrum, related to the annihilation. The high-energy part of the spectrum was used to deduce branching ratios for the so far unobserved annihilation channels: R( p p →π 0 ω) = (2.38 ± 0.65)% , R( p p → π 0 η) = (0.82 ± 0.10% , R p p →π 0γ) = (0.015 ± 0.007)% , and R( p p → π 0 π 0 = (0.06 ± 0.04)% . An upper limit for the π 0 η ′ channel was deduced to be R( p p → π 0 η ′ ) < 1.1% .

1 data table

RESULTS ALSO INCLUDE AN UNKNOWN PARTICLE X WHOSE BRANCHING RATIO IS 1.19 +- 0.25 (DSYS = 0.44) PCT.


>A Measurement of $e^+ e^- \to \bar{p} p$ for 1975-{MeV} $\le \sqrt{s} \le$ 2250-{MeV}

Bisello, D. ; Limentani, S. ; Nigro, M. ; et al.
Nucl.Phys.B 224 (1983) 379, 1983.
Inspire Record 190558 DOI 10.17182/hepdata.33935

The e + e − → p p cross section has been measured in the energy interval (1975 ⩽ 2 E ⩽ 2250) MeV for |cos θ | < 0.7. The measurement is based on ∼ 100 events, thus improving by a factor 3 on the previous existing statistics in this energy interval. The form factor | G | 2 is given as a function of energy under the assumption | G E | = | G M |. We also give the first measurement of the differential cross section, averaged over the energy interval, and estimate the ratio G M |/| G E | from it.

3 data tables

No description provided.

No description provided.

No description provided.


Search for New S Anti-s States in the $K^-$ Induced $K^+ K^-$ System

Armstrong, T. ; Baubillier, M. ; Beusch, W. ; et al.
Nucl.Phys.B 224 (1983) 193-217, 1983.
Inspire Record 190033 DOI 10.17182/hepdata.33934

Results from the first PWA of the K + K − system produced by incident K − , are presented in the mass range from the threshold to 1.70 GeV. In the P and D waves only the φ and f′ mesons are observed and their production mechanism studied. A broad S wave peaking at 1.4 GeV is observed but the lack of information about its phase makes the search for new 0 ++ mesons inconclusive.

4 data tables

ASSUMING BRANCHING RATIO 0.486 FOR PHI --> K+ K-.

No description provided.

No description provided.

More…

Experimental Study of Inclusive Muon Spectra at PETRA

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 51 (1983) 443, 1983.
Inspire Record 13422 DOI 10.17182/hepdata.20492

The results of a high-statistics study of inclusive muon spectra at PETRA are reported. Improved mass limits have been obtained for heavy quarks, heavy leptons, and charged Higgs particles. It is shown that the fragmentation properties of b quarks and c quarks are different, with the mean fragmentation variables 〈zb〉=0.75±0.03±0.06, 〈zc〉=0.46±0.02±0.05 and the average semileptonic branching ratio for the B and C hadrons R(B)=(10.5±1.5±1.3)%, R(C)=(11.5±1.0±1.7)%.

5 data tables

No description provided.

No description provided.

No description provided.

More…

Measurement of the Processes $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \gamma \gamma$ at {PETRA}

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Z.Phys.C 19 (1983) 197, 1983.
Inspire Record 191231 DOI 10.17182/hepdata.45206

Cross sections for the reactionse+e−→e+e− (Bhabha scattering) ande+e−→γγ are measured for center-of-mass (c.m.) energies\(\sqrt s \) between 12.0 and 34.6 GeV. The results agree with the predictions of Quantum Electrodynamics (QED) and the cut-off parameters are determined. From Bhabha scattering at the highest energy,\(\left\langle {\sqrt s } \right\rangle= 34.6 GeV\), the 1 δ limits 0.12

3 data tables

Total cross sections.

Angular distribution.

Angular distribution.


Limits on $J/\psi$ and $\Upsilon$ Production in $e^+ e^-$ Interactions at $\sqrt{s}=29$-{GeV}

Matteuzzi, C. ; Abrams, G.S. ; Amidei, D. ; et al.
Phys.Lett.B 129 (1983) 141-144, 1983.
Inspire Record 189580 DOI 10.17182/hepdata.30662

A search has been made for the inclusive production of J ψ (3.1) and ϒ (9.4) mesons in e + e − interactions at 29 GeV, via their decay into two leptons. No signal is observed in the J ψ region, nor in the ϒ region. The limits on the cross sections are σ ( e + e − → ψX ) < 4.4 × 10 −36 cm 2 , and σ ( e + e − → ϒX ) < 4.7 × 10 −36 cm 2 . The same data yield limits on the branching ratios for the b quark BR ( b → ψX ) < 4.9% and BR ( b → ℓ + ℓ − X ) < 0.8%.

2 data tables

No description provided.

No description provided.


A Model Independent Second Order Determination of the Strong Coupling Constant $\alpha^- s$

Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rev.Lett. 50 (1983) 2051, 1983.
Inspire Record 189724 DOI 10.17182/hepdata.3086

With use of the MARK-J detector at s=34.7 GeV 21 000 e+e−→hadron events have been collected. By measurement of the asymmetry in angular energy correlations the strong coupling constant αs=0.13±0.01 (statistical)±0.02 (systematic) is determined, in complete second order, and independent of the fragmentation models and QCD cutoff values used.

2 data tables

DATA REQUESTED FROM THE AUTHORS.

No description provided.