Ghidini, B.
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rivet Analysis
Measurement of the Radiative Width of the A(2) (1320) in Two Photon Interactions

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gerhards, R. ; et al.
Z.Phys.C 31 (1986) 537, 1986.
Inspire Record 228876 DOI 10.17182/hepdata.15859

The reactione+e−→e+e− A2 (1320) has been observed by detecting the decayA2→π+,π-π0. The two-photon width of theA2 has been measured to be Г(A2→γγ)=(0.09±0.27 (stat)±0.16 (syst)) keV. The cross section σ(γγ→π+,π-π0 has been determined outside theA2 resonance region.

1 data table
Table 1

Data read off a graph.


rivet Analysis
Exclusive Production of Proton Anti-proton Pairs in Photon-photon Collisions

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.
Phys.Lett.B 174 (1986) 350-356, 1986.
Inspire Record 231554 DOI 10.17182/hepdata.30246

Total and differential cross sections for exclusive production of proton-antiproton pairs in photon-photon collisions have been measured using the JADE detector at PETRA. The total cross section in the CM angular |cos θ ∗ | < 0.6 reaches a maximum value of 3.8 nb for a γγ invariant mass of W γγ = 2.25 GeV, and decreases rapidly for higher values of W γγ . In the range 2.0 GeV < W γγ < 2.6 GeV the angular distribution is not isotopic. The nucleons are preferentially emitted at large angles to the collision axis.

2 data tables
Table 1

Data read off graph.

Table 2

Data read off graph.


rivet Analysis
Pion and kaon pair production in photon-photon collisions

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.Lett. 57 (1986) 404, 1986.
Inspire Record 228072 DOI 10.17182/hepdata.20204

We report measurements of the two-photon processes e+e−→e+e−π+π− and e+e−→e+e−K+K−, at an e+e− center-of-mass energy of 29 GeV. In the π+π− data a high-statistics analysis of the f(1270) results in a γγ width Γ(γγ→f)=3.2±0.4 keV. The π+π− continuum below the f mass is well described by a QED Born approximation, whereas above the f mass it is consistent with a QCD-model calculation if a large contribution from the f is assumed. For the K+K− data we find agreement of the high-mass continuum with the QCD prediction; limits on f′(1520) and θ(1720) formation are presented.

5 data tables
Table 1

Data read from graph. Additional overall systematic error 20% not included.

Table 2

Data read from graph.. Additional overall systematic error 20% not included.

Table 3

Data read from graph.. Additional overall systematic error 20% not included.. The Q**2 dependence is normalized to unity for the bin centred on Q**2 = 0.

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Observation of the Decay $B \to$ F X

The CLEO collaboration Haas, P. ; Hempstead, M. ; Jensen, T. ; et al.
Phys.Rev.Lett. 56 (1986) 2781, 1986.
Inspire Record 228879 DOI 10.17182/hepdata.20235

We present evidence for inclusive F-meson production in B-meson decay. The product branching fraction B(B→FX)B(F+→φπ+) is measured to be 0.0038±0.010. The F momentum spectrum indicates the presence of a large component of two-body final states in the decay B→FX.

3 data tables
Table 1

No description provided.

Table 2

DATA SAMPLE CONSISTED OF 77 1/PB. DATA TAKEN ON THE PEAK OF THE UPSI(10575).

Table 3

CONTINUUM DATA SAMPLE CONSISTED OF 36 1/PB. ENERGY JUST BELOW THE UPSI(10575).


HIGH STATISTICS INCLUSIVE phi MESON PRODUCTION AT SPS ENERGIES

The ACCMOR collaboration Dijkstra, H. ; Bailey, R. ; Belau, E. ; et al.
Z.Phys.C 31 (1986) 375-389, 1986.
Inspire Record 18260 DOI 10.17182/hepdata.15894

Inclusive ϕ meson production has been measured for 100 GeV/c and 200 GeV/c incident π−,\(\bar p\) andK−, and for 120 GeV/c and 200 GeV/c incident π+,p andK+, using a Be target. A total of 630,000 ϕ mesons has been recorded in the kinematic range 0

34 data tables
Table 1

Note that the data is plotted in fig. 5 a factor 5 too large. The numbers here are correct.

Table 2

Note that the data is plotted in fig 5 a factor of 5 too large. The numbers here are correct.

Table 3

Note that the data is plotted in fig. 5 a factor of 5 too large. CT = The numbers here are correct.

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Antiproton-proton cross sections at 200 and 900 {GeV} c.m. energy

The UA5 collaboration Alner, G.J. ; Ansorge, R.E. ; Asman, B. ; et al.
Z.Phys.C 32 (1986) 153-161, 1986.
Inspire Record 229896 DOI 10.17182/hepdata.15857

Data on antiproton-proton cross sections at the c.m. energies 200 and 900 GeV are presented. The data were obtained at the CERN antiproton-proton Collider operated in a new pulsed mode in which the same beams were accelerated and decelerated between beam energies of 450 and 100 GeV. The properties of the machine determine the ratio of the luminosities at the two energies to about 1% and thus an accurate measurement of the ratioR of the inelastic cross sections could be made. We findR (=σ900/σ200)=1.20±0.01±0.02, where the first error is statistical and the second systematic. Interpolating existing data to estimateσine1(200 GeV) this measurement ofR leads toσine1(900 GeV)=50.3+0.4+1.0 mb. Using an extrapolated value ofσe1/σtot we estimate the total cross section at 900 GeV to be 65.3±0.7±1.5 mb. Both the inelastic and total cross sections are compatible with a ln2s dependence. Comparisons are made with different fits to the total cross section energy dependence.

2 data tables
Table 1

Ratio of inelastic cross sections at 900 and 200 Gev.

Table 2

Estimate of 900 Gev total cross section based on a) interpolation to obtain total cross section at sqrt(s)=200 Gev (51.6 +- 0.4mb.) b) interpolation and extrapolation to obtain the ratio of elastic to total cross sections at 200 & 900 Gev (0.19 +- 0.01 and 0.23 +- 0.01 respectively).


Inclusive Cross-section Ratios in High $p_T$ Proton Proton Scattering at {ISR} Energies

The Ames-Bologna-CERN-Dortmund-Heidelberg-Warsaw collaboration Breakstone, A. ; Campanini, R. ; Crawley, H.B. ; et al.
Z.Phys.C 35 (1987) 159, 1987.
Inspire Record 229926 DOI 10.17182/hepdata.15764

Ratios of inclusive cross sections σ(π+)/σ(π++K++p) and\(\sigma (\pi ^ -)/\sigma (\pi ^ -+ K^ -+ \bar p)\) were measured for proton-proton interactions with a highpT hadron in the final state around c.m.s. scattering angles θ≅20°, 20° and 45° at two ISR energies\(\sqrt s= 31\) Gev and 62 GeV. Results are shown as functions of transverse and longitudinal momentum and are compared with parton model predictions. The different dependences of positive and negative pion fractions atpT≅2–3 GeV/c on longitudinal momenta is similar to that observed in soft hadronic interactions at low values ofpT where the leading proton effect (diquark fragmentation) is known to contribute. The quantitative agreement of the data with diquark model predictions indicates the presence of diquark fragmentation also in highpT jets.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Direct Photon Production at the {CERN} $\bar{p} p$ Collider

The UA2 collaboration Appel, J.A. ; Bagnaia, P. ; Banner, M. ; et al.
Phys.Lett.B 176 (1986) 239, 1986.
Inspire Record 229895 DOI 10.17182/hepdata.30247

Using the UA2 apparatus, the inclusive cross section has been measured for production of high- p T direct photons in p̄p collisions at s =546 GeV and s =630 GeV . The results are in good agreement with QCD predictions.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Analysis of the Fragmentation Properties of Quark and Gluon Jets at the CERN SPS $p \bar{p}$ Collider

The UA1 collaboration Arnison, G. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Nucl.Phys.B 276 (1986) 253-271, 1986.
Inspire Record 229898 DOI 10.17182/hepdata.33618

A sample of two-jet events from the UA1 experiment at the CERN $p \bar{p}$ Collider has been used to study the fragmentation of high-energy quark and gluon jets into charged hadrons. Compared with lower-energy jets observed in $e^+ e^−$ and $pp$ collisions, the fragmentation function measured in the present experiment is softer (i.e. peaked to smaller values of z) and the mean internal transverse momentum is larger, mainly because of the effects of the QCD scaling violations. Using our knowledge of the quark and gluon structure functions in the proton, together with the QCD matrix elements, a statistical separation of quark and gluon jets is achieved within the present experiment. The fragmentation function for the gluon jets is found to be softer, and the angular spread of the fragmentation products larger, than is the case for quark jets.

1 data table
Table 1

No description provided.


The Production and Decay of Tau Leptons

The Mark-J collaboration Adeva, B. ; Ansari, S. ; Becker, U. ; et al.
Phys.Lett.B 179 (1986) 177-182, 1986.
Inspire Record 230298 DOI 10.17182/hepdata.14556

A study of τ-lepton production in the CMS energy region from 14 to 46.8 GeV at PETRA is reported. The cross section, the decay branching ratio into μν ν , and the electroweak parameters are determined with a total integrated luminosity of 115 pb −1 .

4 data tables
Table 1

Total cross section calculated from measured channel cross section assuming BR(tau-mu) = 17.6 pct. SIG(Q=MU) is the QED point cross section.

Table 2

No description provided.

Table 3

No description provided.

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