Fries, R.
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Fragmentation of Heavy Quarks Produced in $e^+ e^-$ Annihilation

Fernandez, E. ; Ford, William T. ; Read, Alexander L. ; et al.
Phys.Rev.Lett. 50 (1983) 2054, 1983.
Inspire Record 189417 DOI 10.17182/hepdata.20548

Identification of muons in hadronic events from e+e− annihilation observed in the MAC detector at the storage ring PEP provides flavor tagging of heavy primary quarks. A sample enriched in events from bb¯ production is obtained and the b-quark fragmentation function is inferred from the momentum spectrum of the muons. The b quark is found to fragment predominantly with high values of z, with 〈zb〉=0.8±0.1, and to have an over-all semimuonic branching fraction of (15.5−2.9+5.4)%.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Spin Rotation Measurements in $\pi^- p \to K^0 \Lambda$

Bell, Kenneth Watson ; Blissett, J.A. ; Broome, T.A. ; et al.
Nucl.Phys.B 222 (1983) 389-410, 1983.
Inspire Record 190232 DOI 10.17182/hepdata.33946

The first measurements of spin-rotation in meson-baryon scattering in the resonance region are presented. These measurements, for the reaction π − p → K 0 Λ , confirm the main predictions of a previous partial-wave analysis. Comments are made on resonant couplings in the reaction π − p → K 0 Λ .

4 data tables
Table 1

SPIN ROTATION ANGLE MEASUREMENTS.

Table 2

POLARIZATION MEASUREMENTS FROM THIS EXPERIMENT ALONE.

Table 3

COMBINED WITH DATA FROM BAKER ET AL., AND SAXON ET AL., (SEE COMMENTS).

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Experimental Study of the Hadronic Photon Structure Function

The CELLO collaboration Behrend, H.J. ; Fenner, H. ; Gumpel, U. ; et al.
Phys.Lett.B 126 (1983) 391-397, 1983.
Inspire Record 198110 DOI 10.17182/hepdata.30720

We have measured at PETRA the process e γ → e + hadrons at an average Q 2 value of 9 GeV 2 / c 2 . The total number of observed events attributed to this process is 215. Our data are compared to calculations based on the estimation of the photon structure function F 2 in the quark parton model and in QCD.

1 data table
Table 1

No description provided.


Production of $\pi^0$ mesons in muon - hydrogen interactions at 200-GeV

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Z.Phys.C 18 (1983) 189, 1983.
Inspire Record 189283 DOI 10.17182/hepdata.16369

Thez andpT2 distributions of π0 mesons produced by the interaction of 200 GeV muons on hydrogen are presented. Comparisons are made with other π0 and charged hadron data and with the predictions of perturbative QCD. The data show a rise of 〈pT2〉 withW2 which is consistent with QCD, and withz2 which requires a contribution from a primordialkT. The fraction of total energy which appears as π0 mesons is 0.27±0.05.

1 data table
Table 1

No description provided.


Multiplicities of Secondary Hadrons Produced in Neutrino $p$ and Anti-neutrino $p$ Charged Current Interactions

The Aachen-Birmingham-Bonn-CERN-London-Munich-Oxford collaboration Grassler, H. ; Lanske, D. ; Schulte, R. ; et al.
Nucl.Phys.B 223 (1983) 269-295, 1983.
Inspire Record 189061 DOI 10.17182/hepdata.33964

In an experiment with the hydrogen bubble chamber BEBC at CERN multiplicities of hadrons produced in νp and v p interactions have been investigated. Results are presented on the multiplicities of charged hadrons and neutral pions, forward and backward multiplicities of charged hadrons and correlations between forward and backward multiplicities. Comparisons are made with hadronic reactions and e + e − annihilation. In the framework of the quark-parton model the data imply similar charged multiplicities for the fragments of a u- and a d-quark, and a larger multiplicities for the fragments of a uu- than for a ud-diquark. The correlation data suggest independent fragmentation of the quark and diquark for hadronic masses above ∼ 7 GeV and local charge compensation within an event.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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High $p_T$ Direct Photon Production at 11-degrees in $p p$ Collisions at $\sqrt{s}=63$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 123 (1983) 367-372, 1983.
Inspire Record 188929 DOI 10.17182/hepdata.30744

The production of direct photons has been measured relative to π 0 's in the rapidity range 2.00 < y < 2.75 in pp collisions at s = 63 GeV at the CERN Intersecting Storage Rings. The γ/π 0 ratio increases from ⪅2% at p T = 1.5 GeV/ c to ∼8% at p T = 4.25 GeV/ c , similar to the value observed near 90°. The results indicate no strong enhancement of single-photon production due to quark bremsstrahlung in this kinematic region.

1 data table
Table 1

No description provided.


Inclusive electron Production in e+ e- Annihilation at 29-GeV

Nelson, M.E. ; Blondel, A. ; Trilling, G. ; et al.
Phys.Rev.Lett. 50 (1983) 1542, 1983.
Inspire Record 188964 DOI 10.17182/hepdata.38161

The total momentum and transverse momentum spectra of electrons in e+e− annihilation at 29 GeV have been measured. The inclusive cross section is determined to be 14.4±1.6±5.2 pb for momenta greater than 2 GeV/c. The average semielectronic branching ratios of charm and bottom quarks are measured to be (6.3±1.2±2.1)% and (11.6±2.1±1.7)%, respectively. The fragmentation function for bottom quarks is determined to be peaked at high z, with 〈z〉b=0.75±0.05±0.04.

2 data tables
Table 1

PT is the transverse momentum of the muon relative to the event thrust axis.

Table 2

PT is the transverse momentum of the muon relative to the event thrust axis.


Production of $\pi^0$ and Eta0 at 11-degrees in $p p$ Collisions at $\sqrt{s}=63$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Z.Phys.C 18 (1983) 5, 1983.
Inspire Record 188928 DOI 10.17182/hepdata.16326

The inclusive π0 production cross-section and the η/π0 ratio have been measured inpp collisions at\(\sqrt s= 63 GeV\) at the CERN Intersecting Storage Rings in the rapidity range 2.00<y<2.75. The π0 cross-section exhibits a strongy-dependence and falls more steeply as a function ofpT, compared with the cross-section measured aty∼0. We find a value of 0.46±0.07 for the η/π0 ratio with no significantpT dependence over the range 2.0<pT<4.0 GeV/c.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


SEARCH FOR LAMBDA p STATES IN THE BARYON EXCHANGE REACTION p p ---> LAMBDA p K+ AT 11.75-GeV/c

Arenton, M.W. ; Ayres, D.S. ; Diebold, R. ; et al.
Phys.Rev.D 28 (1983) 657, 1983.
Inspire Record 188917 DOI 10.17182/hepdata.23770

We have obtained 1400 events of the baryon-exchange reaction pp→ΛpK+ using the ANL Zero Gradient Synchrotron 11.75-GeV/c polarized proton beam and the effective-mass spectrometer. A search for enhancements in the Λp mass spectrum has been made. No enhancements are observed; in particular, the narrow Λp enhancement at 2.13 GeV seen in K−d→Λpπ− is not observed. We establish limits on the production of narrow states of ∼ 10 nb. Also, 100000 events of the forward reaction pp→ΛK+p were examined and no narrow Λp enhancements are seen.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


INCLUSIVE K0(S) LAMBDA AND anti-LAMBDA PRODUCTION IN anti-p p INTERACTIONS AT 22.4-GeV/c

The Alma Ata-Dubna-Helsinki-Moscow-Prague-Tbilisi collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Gramenitsky, I.M. ; et al.
Z.Phys.C 25 (1984) 213, 1984.
Inspire Record 194651 DOI 10.17182/hepdata.2004

InclusiveKs0, Λ and\(\bar \Lambda\)-production has been investigated in\(\bar p\)p-interactions at 22.4 GeV/c. Total and topological cross sections and multiplicity characteristics of neutral strange particles have been determined. DifferentialKs0 and Λ-cross sections and also characteristics of annihilation processes with neutral kaon production have been studied. It is shown that the difference of the shapes of the invariantx-distributions forK-mesons in the fragmentation region for annihilation and non-annihilation processes can be described in the framework of the “dual” valon model, but not by considering the current (undressed) quark recombination mechanisms only. The polarization of Λ and\(\bar \Lambda\)-hyperons has been measured.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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