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.


An Analysis of the Charged and Neutral Energy Flow in $e^+ e^-$ Hadronic Annihilation at 34-{GeV}, and a Determination of the {QCD} Effective Coupling Constant

The CELLO collaboration Behrend, H.J. ; Chen, C. ; Fenner, H. ; et al.
Phys.Lett.B 113 (1982) 427-432, 1982.
Inspire Record 177228 DOI 10.17182/hepdata.30921

Using both charged and neutral components, 2600 multihadronic e + e − annihilation events, recorded at 34 GeV by the CELLO detector at PETRA, have been analysed in a calometric approach. The fraction of energy carried by gamma rays is measured to be f γ = (26.0 ± 0.4 (stat) ± 4.0 (syst)%. The neutral energy flow is seen to follow closely the overall energy flow. From the corrected oblateness distribution, a first order determination of α s is performed. The result is α s = 0.16 ± 0.01 (stat) ± 0.03 (syst).

1 data table
Table 1

No description provided.