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rivet Analysis
Charged Pion, Kaon, Proton and anti-Proton Production in High-Energy e+ e- Annihilation

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.

Phys.Lett.B 94 (1980) 444-449, 1980.

Inspire Record 153656 DOI 10.17182/hepdata.27192

Production of pions, kaons, protons and antiprotons has been studied in e + e − annihilations at 12 and 30 GeV centre of mass energy using time of flight techniques. The fractional yield of charged kaons and baryons appears to rise with outgoing particle momentum. At our highest energy at least 40% of e + e − annihilations into hadrons are estimated to contain baryons.

13 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Forward $K^*$+ (892) Production in $K^+ p \to \pi^+ K^0_S p$ at 12.7-{GeV}/$c$

Sacharidis, E.J. ; Blum, W. ; Dietl, H. ; et al.

Nucl.Phys.B 179 (1981) 9-32, 1981.

Inspire Record 154321 DOI 10.17182/hepdata.34347

We have measured 618 K + p → π + K S 0 p events at 12.7 GeV/ c incident lab momentum, mass range 790 ⩽ m π + K s 0 ⩽ 990 MeV and t range 0.01 ⩽ − t ⩽ 0.60 (GeV/ c ) 2 . The π + K S 0 mass spectrum is dominated by the K ∗+ (892) resonance and a Breit-Wigner fit yields a mass m = 893.5 ± 1.1 MeV and a width Γ = 33.2 ± 4.1 MeV which is much narrower than measured hitherto. The t distribution of K ∗+ (892) events shows a dip in the forward direction and an exponential fall off thereafter, consistent with dominance of helicity flip amplitudes. The spin density matrix is almost saturated by ρ 11 and ρ 1−1 which are very close to their maximum allowed value of 1 2 throughout the measured t range except in the very forward direction where ρ 00 and Re ρ 10 deviate from zero. Natural parity exchanges, therefore, dominate with unnatural parity exchanges being restricted to a small region in the forward direction. A Regge pole analysis of the differential cross sections of the present measurement in conjunction with previously measured total cross sections supports the f-coupled-pomeron hypothesis.

3 data tables

Table 1

SUBTRACTED BACKGROUND IS PHASE SPACE.

Table 2

SUBTRACTED BACKGROUND IS AN INCOHERENT S-WAVE WITH EXPONENTIAL T-DEPENDENCE WITH SLOPE OF 6 GEV**-2.

Table 3

Axis error includes +- 15/15 contribution.

INCLUSIVE MUON PRODUCTION AT PETRA ENERGIES

The Pluto collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.

Phys.Rev.Lett. 45 (1980) 1533-1537, 1980.

Inspire Record 153812 DOI 10.17182/hepdata.20692

In this Letter, a measurement of inclusive muon production (pμ>2 GeV/c) in e+e− annihilation into hadrons at center-of-mass energies from s=12 to 31.6 GeV is reported. The results agree with the expected semileptonic decays from charmed and bottom mesons.

2 data tables

Table 1

MUONS PER HADRONIC EVENT.

Table 2

INVARIANT CROSS SECTION, ASSUMING HADRONIC CROSS SECTION HAS R VALUE OF 3.9 +- 0.5.

Measurements of the Properties of d Meson Decays

Schindler, R.H. ; Alam, M.S. ; Boyarski, A. ; et al.

Phys.Rev.D 24 (1981) 78, 1981.

Inspire Record 156644 DOI 10.17182/hepdata.24006

We present a study of the decay properties of charmed D mesons produced near the peak of the ψ′′(3770) resonance in e+e− annihilation. Branching fractions for nine Cabibbo-favored and three Cabibbo-suppressed decay modes are presented along with upper limits on one additional Cabibbo-favored and four additional Cabibbo-suppressed decay modes. A study of Kππ-decay-mode Dalitz plots reveals a large quasi-two-body pseudoscalar-vector component for the D0 decays and an apparent nonuniform population on the Dalitz plot for the D+ decay into K−π+π+. Using tagged events, we measure the charged-particle multiplicity and strange-particle content of D decays. A measurement of the D+ and D0 semileptonic decay fractions indicates that the D+ has a significantly longer lifetime than the D0.

1 data table

Table 1

INCLUSIVE CROSS SECTIONS UNCORRECTED FOR RADIATIVE EFFECTS.

rivet Analysis
$K^0$ Production in $e^+ e^-$ Annihilations at 30-{GeV} Center-of-mass Energy

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.

Phys.Lett.B 94 (1980) 91-95, 1980.

Inspire Record 153341 DOI 10.17182/hepdata.27173

Inclusive K 0 -production has been measured in e + e - annihilation at a center of mass energy of about W = 30 GeV. The ratio of K 0 + K 0 production to μ + μ - production is R K 0 = 5.6 ± 1.1 (statist. error) ± 0.8 (system.error) This value is about a factor of three higher than R K 0 at W = 7 GeV. The cross sections ( s / β ) d σ /d x is consistent with a scaling behaviour.

4 data tables

Table 1

No description provided.

Table 2

DIFFERENTIAL CROSS SECTION.

Table 3

INVARIANT CROSS SECTION.

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Results From a $\pi^-$p Slow Proton Trigger Experiment at 12 GeV/c

Evangelista, C. ; Ghidini, B. ; Palano, A. ; et al.

Nucl.Phys.B 178 (1981) 197-241, 1981.

Inspire Record 153471 DOI 10.17182/hepdata.34350

A study of the reaction π − p → X − p based on 1.27 × 10 6 events, corresponding to a mean sensitivity of 200 events/μb, is presented. Properties of the exclusive channels π − p → π − π 0 p, π + π − π − p, π + π − π − π 0 p, π + π + π − π − π − p and π + π + π − π − π − π 0 p are discussed.

9 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Comparison of e+ e- Annihilation with QCD and Determination of the Strong Coupling Constant

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.

Phys.Lett.B 94 (1980) 437-443, 1980.

Inspire Record 153511 DOI 10.17182/hepdata.5489

We have analyzed 1113 events of the reaction e + e − → hadrons at CM energies of 12 and 30 GeV in order to make a detailed comparison with QCD. Perturbative effects can be well separated from effects depending on the quark and gluon fragmentation parameters to yield a reliable measurement of the coupling constant α S . At 30 GeV, the result is α S = 0.17 ± 0.02 (statistical) ± 0.03 (systematic). QCD model predictions, using the fragmentation parameters determined along with α S , agree with both gross properties of the final states and with detailed features of the three-jet states.

7 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of Dimuon Production at the {ISR}

Antreasyan, D. ; Atwood, W. ; Battiston, R. ; et al.

Phys.Rev.Lett. 45 (1980) 863, 1980.

Inspire Record 153857 DOI 10.17182/hepdata.20656

Prompt dimuon production has been measured. Events with mass up to 25 GeV/c2 are observed, as well as the J and ϒ resonances. Cross sections are given for J and ϒ production. For the continuum, the scaling function F(τ) is measured at very small values of τ=ms covering the range 0.05<τ<0.20.

3 data tables

Table 1

No description provided.

Table 2

HERE UPSILON = ALL USILON FAMILY. ANGULAR DISTBN. IS SEEN TO BE ISOTROPIC.

Table 3

No description provided.

ANGULAR DEPENDENCE OF HIGH P(T) pi0 PRODUCTION

Lloyd Owen, D. ; Abshire, G.W. ; Finocchiaro, G. ; et al.

Phys.Rev.Lett. 45 (1980) 89, 1980.

Inspire Record 153201 DOI 10.17182/hepdata.20655

The π0 inclusive cross section for c.m. production angles θ=90° and 22°>~θ>~5° at c.m. energies of s=23 and 53 GeV has been measured. This cross section is strongly dependent on both θ and s at small angles. The hypothesis of radial scaling is shown to be incapable of incorporating both θ and s dependence of the cross section. A recent quantum-chromodynamics calculation is in qualitative agreement with our results.

14 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.