Akopov, N.
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The D0 Spectrum From $B$ Meson Decay

The CLEO collaboration Green, J. ; Hicks, R.G. ; Sannes, F. ; et al.
Phys.Rev.Lett. 51 (1983) 347, 1983.
Inspire Record 190327 DOI 10.17182/hepdata.20493

The inclusive branching fraction for B-meson decay into D0 mesons and the momentum spectrum of the D0's have been measured. 0.8±0.2±0.2 D0 per B decay was found. The shape of the spectrum suggests an interesting picture of B-meson decay.

1 data table
Table 1

NUMBER OF D0'S FROM UPSI(4S) REGION AFTER CORRECTION FOR THE CONTINUUM CONTRIBUTION.


Measurements of Spin Spin Correlation Parameters Up to 2.5-{GeV}/$c$ Incident Momentum for a Decisive Clarification of the Structure Observed in the $p p$ System

Auer, I.P. ; Colton, E. ; Ditzler, W.R. ; et al.
Phys.Rev.Lett. 51 (1983) 1411, 1983.
Inspire Record 191101 DOI 10.17182/hepdata.20512

Recent data are presented on spin-spin correlation parameters CLL=(L,L;0,0) and CSL=(S,L;0,0) at forward angles from 1.18 to 2.47 GeV/c incident momenta in proton-proton elastic scattering. Values for ΔσL (inelastic) are derived and are shown to disagree with predictions of theoretical models attempting to describe p−p scattering without dibaryon resonances. Finally, the CLL and CSL data discriminate among various phase-shift solutions, and will lead to a clarification of the p−p phase shifts.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Observation of Baryons in $B$ Meson Decay

The CLEO collaboration Alam, M.S. ; Csorna, S.E. ; Garren, L. ; et al.
Phys.Rev.Lett. 51 (1983) 1143, 1983.
Inspire Record 190324 DOI 10.17182/hepdata.20526

In a sample of B mesons from the decay of the ϒ(4S) produced in e+e− collisions at the Cornell Electron Storage Ring, inclusive protons, antiprotons, lambdas, and antilambdas have been observed. Lower limits to the B-to-baryon branching ratios are derived.

2 data tables
Table 1

NUMERICAL VALUES OF DATA SUPPLIED BY E.H. THORNDIKE. CORRECTED ANTI(PROTON) PRODUCTION FROM UPSI(4S) DECAY.

Table 2

NUMERICAL VALUES OF DATA SUPPLIED BY E.H. THORNDIKE. CORRECTED ANTI(LAMBDA) PRODUCTION FROM UPSI(4S) DECAY.


Elastic and total cross-section measurement at the CERN proton-antiproton collider

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.
Phys.Lett.B 128 (1983) 336, 1983.
Inspire Record 190339 DOI 10.17182/hepdata.30668

Proton-antiproton elastic scattering at CM energy 540 GeV has been studied in the t -range 0.04 < − t < 0.45 GeV 2 . The data are well fitted by the form exp ( bt ) with b = 17.1 ± 1.0 GeV −2 for | t | = 0.04 − 0.18 GeV su 2 and b = 13.7 ± 0.2 ± 0.2 GeV −2 for | t | = 0.21−0.45 GeV 2 . A luminosity measurement combined with the optical theorem gives σ tot = 67.6 ± 5.9 ± 2.7 mb and σ e1 / σ tot = 0.209 ± 0.018 ± 0.008.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

ELASTIC RATIO ASSUMES RHO=0.


Limits on $J/\psi$ and $\Upsilon$ Production in $e^+ e^-$ Interactions at $\sqrt{s}=29$-{GeV}

Matteuzzi, C. ; Abrams, G.S. ; Amidei, D. ; et al.
Phys.Lett.B 129 (1983) 141-144, 1983.
Inspire Record 189580 DOI 10.17182/hepdata.30662

A search has been made for the inclusive production of J ψ (3.1) and ϒ (9.4) mesons in e + e − interactions at 29 GeV, via their decay into two leptons. No signal is observed in the J ψ region, nor in the ϒ region. The limits on the cross sections are σ ( e + e − → ψX ) < 4.4 × 10 −36 cm 2 , and σ ( e + e − → ϒX ) < 4.7 × 10 −36 cm 2 . The same data yield limits on the branching ratios for the b quark BR ( b → ψX ) < 4.9% and BR ( b → ℓ + ℓ − X ) < 0.8%.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


CHARM PHOTOPRODUCTION CROSS-SECTION AT 20-GeV

Abe, K. ; Bacon, T.C. ; Ballam, Joseph ; et al.
Phys.Rev.Lett. 51 (1983) 156, 1983.
Inspire Record 189662 DOI 10.17182/hepdata.20508

Forty-seven charm events have been observed in an exposure of the SLAC Hybrid Facility bubble chamber to a 20-GeV backward-scattered laser beam. Thirty-seven events survive all the necessary cuts imposed. Based on this number the total charm cross section is calculated to be 63−28+33 nb.

1 data table
Table 1

No description provided.


A Comparison of the Deep Inelastic Structure Functions of Deuterium and Aluminum Nuclei

Bodek, A. ; Giokaris, N. ; Atwood, W.B. ; et al.
Phys.Rev.Lett. 51 (1983) 534, 1983.
Inspire Record 189856 DOI 10.17182/hepdata.20489

The deep-inelastic electromagnetic structure functions of deuterium and aluminum nuclei have been measured. The kinematic dependence of the ratio of aluminum and deuterium structure functions is similar to the dependence of the ratio of steel and deuterium structure functions, and provides further evidence for the distortion of the quark momentum distributions of nucleons bound in a nucleus.

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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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.


D*+- Production by e+ e- Annihilation Near 34.4-GeV Center-Of-Mass Energy

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 126 (1983) 493-498, 1983.
Inspire Record 196842 DOI 10.17182/hepdata.30721

D ∗± production via e + e − →D ∗± X has been measured at an average CM energy of 34.4 GeV. The D ∗± energy spectrum is hard, with a maximum near χ = 0.6. The size of the D ∗ cross section, R D ∗ = σ( e + e − → D ∗ X ) σ μμ = 2.50 ± 0.64 ± 0.88 (assuming R D ∗0 = R D ∗+ ) indicates that a large fraction of charm quark production yields D ∗ mesons. The D ∗± angular distribution exhibits a forward—backward asymmetry, A = −0.28 ± 0.13. This is consistent with that expected in the standard theory for weak neutral currents and leads to | g A c | = 0.89 ± 0.44 for the axial vector coupling of the charm quark.

3 data tables
Table 1

ASSUMES EQUAL RATES FOR CHARGED AND NEUTRAL D*'S. ONLY CHARGED ARE DETECTED.

Table 2

DATA PEAKS AT X=0.6 TO 0.8.

Table 3

ASYMMETRY MEASUREMENT. THETA IS THE ANGLE BETWEEN THE E- AND THE D*.