Schroder, Matthias
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Observation of a Narrow Resonance at 9.46-GeV in electron-Positron Annihilations

Darden, C.W. ; Hasemann, H. ; Krolzig, A. ; et al.
Phys.Lett.B 76 (1978) 246, 1978.
Inspire Record 130052 DOI 10.17182/hepdata.27447

We observe a narrow resonance in the reaction e + e − → hadrons using the DASP detector at the DORIS storage ring. The mass is found to be (9.46 ± 0.01) GeV and the observed width is compatible with the storage ring resolution of ±8 MeV. The energy-integrated cross section results in an electronic width Γ ee = (1.3 ± 0.4) keV.

1 data table
Table 1

VISIBLE HADRONIC TOTAL CROSS SECTION.


Evidence for a Narrow Resonance at 10.01-GeV in electron-Positron Annihilations

Darden, C.W. ; Hasemann, H. ; Krolzig, A. ; et al.
Phys.Lett.B 78 (1978) 364-365, 1978.
Inspire Record 131898 DOI 10.17182/hepdata.27427

We observe evidence for a secon narrow resonance in the reation e + e − → hadrons at √s around 10 GeV using the DASP detector at the DORIS storage ring. The mass of the resonance is (10.01 ± 0.02) GeV; its width is in agreement with the storage ring resolution of ≈ 9 MeV. From the integrated cross section, an electronic width of Λ ee = (0.35 ± 0.14) KeV is derived.

1 data table
Table 1

No description provided.


STUDY OF THE UPSILON (9.46) MESON IN ELECTRON - POSITRON ANNIHILATIONS

Darden, C.W. ; Hasemann, H. ; Krolzig, A. ; et al.
Phys.Lett.B 80 (1979) 419-422, 1979.
Inspire Record 145168 DOI 10.17182/hepdata.27358

New data for the reaction e + e − →ϒ(9.46) have been obtained using the DASP detector at the DORIS storage ring. The electronic width Γ ee is (1.5±0.4) keV. The branching ratio for the decay into muon pairs is (2.5 ± 2.1)%. Energy spectra for inclusive production of hadrons are given.

2 data tables
Table 1

VISIBLE HADRONIC TOTAL CROSS SECTION.

Table 2

INVARIANT INCLUSIVE PRODUCTION CROSS SECTION E*D3(SIG)/DP**3 BOTH ON AND OFF THE UPSILON(9.46) RESONANCE. NO SIGNIFICANT DIFFERENCE IN EXPONENTIAL SLOPE AS A FUNCTION OF PARTICLE ENERGY E(P=3).


Inclusive $K^*$+- (892) Production in $p p$ and $\pi^+ p$ Interactions

The Bonn-Hamburg-Munich & Aachen-Bonn-CERN-Cracow collaborations Bockmann, K. ; Hofmann, J. ; Lowsky, J. ; et al.
Nucl.Phys.B 166 (1980) 284-300, 1980.
Inspire Record 144126 DOI 10.17182/hepdata.8001

A study is presented of the inclusive production cross sections of K ∗± (892) vector mesons in pp interactions at 12 and 24 GeV/ c and in π + p interactions at 16 GeV/ c . The K ∗± inclusive cross section is ∼0.9 mb for both pp at 24 GeV/ c and π + p interactions at 16 GeV/ c . For pp interactions, σ( K ∗+ ) and σ( K ∗− ) are seen to rise with energy, showing a threshold behaviour. In both pp and π + p interactions, σ( K ∗+ ) largely exceeds σ( K ∗− ) at these energies and this excess is interpreted as K ∗+ production by beam and target fragmentations. The decays of K ∗±0 yield ∼30% of the K 0 observed in the final states. The p T 2 dependence of both K ∗+ and K ∗ − cross sections is described by an exponential with slope of ∼3.3 (GeV/ c ) −2 . The longitudinal momentum spectra for K ∗+ in 16 GeV/ c π + p and 24 GeV/ c pp interactions are similar in shape in the target hemisphere. The K ∗− spectra are similar over the whole kinematic region when viewed in the quark c.m.s. and point to a central production mechanism. Comparing K ∗+ and ρ 0 production, striking similarities are found.

8 data tables
Table 1

No description provided.

Table 2

ASSUMED SIG(KS)=SIG(KL).

Table 3

No description provided.

More…

A Determination of the Total Width of the $\Upsilon$ (9.46) Meson

Albrecht, H. ; Childers, R. ; Darden, C.W. ; et al.
Phys.Lett.B 93 (1980) 500-504, 1980.
Inspire Record 153029 DOI 10.17182/hepdata.6334

Using the DASP detector at the DESY storage ring DORIS we have continued measuring e + e − annihilations near and on the ϒ(9.46) resonance. From the cross sections for e + e − → μ + μ − and e + e − → hadrons we obtain a μ + μ − branching ratio for the ϒ(9.46) of (2.9 ± 1.3 ± 0.5) %, a leptonic width г ee = (1.35 ± 0.11 ± 0.22) keV and a total width of (47 −15 +37 keV.

2 data tables
Table 1

VISIBLE HADRONIC CROSS SECTION. PEAK VALUE AT UPSILON IS 10.1 +- 0.7 NB.

Table 2

No description provided.


Cross-section and $p \bar{p}$ Invariant Mass Distribution of the Reaction $\gamma p \to p \bar{p} p$ at 4.7-{GeV} $\le e \gamma \le$ 6.6-{GeV}

Bodenkamp, J. ; Fries, D.C. ; Markou, A. ; et al.
Phys.Lett.B 133 (1983) 275-278, 1983.
Inspire Record 10564 DOI 10.17182/hepdata.30612

Cross section and pp¯ in variant mass distribution of the reaction γp→pp¯p are presented. Further evidence for a narrow pp¯ mass state at 2.023 GeV will be given.

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////SYSTEMATIC ERRORS HAVE BEEN FOLDED IN QUADRATURE WITH STATISTICAL ERRORS).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////SYSTEMATIC ERRORS HAVE BEEN FOLDED IN QUADRATURE WITH STATISTICAL ERRORS).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////SYSTEMATIC ERRORS HAVE BEEN FOLDED IN QUADRATURE WITH STATISTICAL ERRORS).


Measurement of $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \gamma \gamma$ at Energies Up to 36.7-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Field, J. ; et al.
Phys.Lett.B 103 (1981) 148-152, 1981.
Inspire Record 165288 DOI 10.17182/hepdata.31169

The differential cross sections of the reactions e + e − → e + e − and e + e − → λλ are measured at energies between 33.0 and 36.7 GeV. The results agree with the predictions of quantum electrodynamics. A comparison with the standard model of electroweak interaction yields sin 2 θ W = 0.25 ± 0.13.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
SEARCH FOR NARROW QUARKONIUM STATES AND PAIR PRODUCTION OF NEW HEAVY QUARKS AT c.m. ENERGIES FROM 33-GeV TO 36.7-GeV

The CELLO collaboration Behrend, H.J. ; Chen, Ch. ; Field, J.H. ; et al.
DESY-81-029, 1981.
Inspire Record 166365 DOI 10.17182/hepdata.45222

None

1 data table
Table 1

CONTINUOUS COVERAGE OF THREE ENERGY RANGES (33.00 TO 33.80, 34.00 TO 35.26 AND 36.08 TO 36.72 GEV PLUS SEVEN ADDITIONAL DATA POINTS AROUND 35.7 GEV).


Topology of Hadronic $e^+ e^-$ Annihilation Events at 22-{GeV} and 34-{GeV} Center-of-mass Energy

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Field, J.H. ; et al.
Phys.Lett.B 110 (1982) 329-334, 1982.
Inspire Record 169195 DOI 10.17182/hepdata.30996

The topology of hadronic e + e − annihilation events has been analysed using the sphericity tensor and a cluster method. Comparison with quark models including gluon bremsstrahlung yields good agreement with the data. The strong-coupling constant is determined in 1st order QCD to be α S =0.19±0.04 (stat) ± 0.04 (syst.) at 22 GeV and α S =0.16 ±0.02± 0.03 at 34 GeV. The differential cross section with respect to the energy fraction carried by the most energetic parton agrees with the prediction of QCD, but cannot be reproduced by a scalar gluon model. These results are stable against variations of the transverse momentum distribution of the fragmentation function within the quoted errors.

1 data table
Table 1

No description provided.


Measurement of Inclusive $\gamma$ and $\pi^0$ Spectra and a Comparison of the Neutral and Charged Components in Hadronic Events in $e^+ e^-$ Annihilation at 34-{GeV}

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Z.Phys.C 14 (1982) 189, 1982.
Inspire Record 177212 DOI 10.17182/hepdata.16411

The photonic part of multihadronice+e− annihilation events has been analyzed at a c.m. energy of 34 GeV. The photonic energy fraction per event is determined to befγ=0.251±0.003 (stat.) ±0.04 (syste.). The neutral and charged components of the events are analyzed separately revealing close similarity in thrust axis directions and momentum distributions in agreement with the hypothesis that most photons result from π0 decay. π0's are reconstructed separately and used to determine the inclusive cross section. Comparing these cross sections with lower energy data from SPEAR we find some indication for scaling violation.

2 data tables
Table 1

No description provided.

Table 2

No description provided.