Qi, N.
E+ E- Scattering
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Production of Charmed Mesons in $e^+ e^-$ Annihilation at 10.5-{GeV}

The CLEO collaboration Avery, P. ; Bebek, C. ; Berkelman, Karl ; et al.
Phys.Rev.Lett. 51 (1983) 1139, 1983.
Inspire Record 191835 DOI 10.17182/hepdata.20524

A measurement is presented of the inclusive production of charged D* and neutral D mesons from nonresonant e+e− annihilation in the energy region near the ϒ(4S) resonance. The momentum distribution shows a large contribution at high momenta as expected for heavy quark production. Comparison of the spectrum with several phenomenological models is made. The relative yields of the D* and D mesons indicate that the charm cross section is dominated by the D* contribution.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
Differential Cross-sections for $\gamma \gamma \to p \bar{p}$ in the Center-of-mass Energy Range From 2.0-{GeV} to 3.1-{GeV}

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 130 (1983) 449-453, 1983.
Inspire Record 191417 DOI 10.17182/hepdata.6654

Exclusive production of proton-antiproton pairs by two photon scattering at CM energies between 2.0 GeV and 3.1 GeV has been measured with the TASSO detector at the e + e − storage ring PETRA. The angular distribution is flat within the accepted CM angular range | cos Θ ∗ |⩽0.7 . The integrated cross section (| cos Θ ∗ |⩽0.6) drops from about 4 nb at 2 GeV to less than 0.5 nb above 3 GeV. For the two-photon production of the η c (2984) and its subsequent decay into proton-antiproton the upper limit Γ(η c →γγ)· B (η c → p p )<0.32 keV (95% CL) is found.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

UPPER LIMIT FOR THE PRODUCT OF THE ETA/C --> GAMMA GAMMA WIDTH AND THE BRANCHING RATIO OF ETA/C --> P AP IS DETERMINED TO BE 0.32 KEV WITH 90 PCT CL.

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Evidence for the F Meson at 1970-MeV

The CLEO collaboration Chen, A. ; Goldberg, M. ; Horwitz, N. ; et al.
Phys.Rev.Lett. 51 (1983) 634, 1983.
Inspire Record 190325 DOI 10.17182/hepdata.20490

Evidence is presented for a narrow meson resonance of mass 1970±5±5 MeV produced in continuum e+e− annihilations at s of 10.5 GeV, and decaying into a ϕ and a charged π.

1 data table
Table 1

CROSS SECTION OVER ALL F MOMENTA CALCULATED ASSUMING SPECTRUM BELOW 2.5 HAS SAME SHAPE AS D MESON PRODUCTION.


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.


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.


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.


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*.


rivet Analysis
A Measurement of the Branching Fraction of the Decay $\Upsilon$ (1s) $\to \tau^+ \tau^-$

The CLEO collaboration Giles, R. ; Hassard, J. ; Hempstead, M. ; et al.
Phys.Rev.Lett. 50 (1983) 877, 1983.
Inspire Record 188803 DOI 10.17182/hepdata.20525

The branching fraction for the decay of the ϒ(1S) into τ paris has been measured to be (3.4±0.4±0.4)%. This result agrees with the previously measured branching ratio of the decay into muon pairs.

2 data tables
Table 1

VISIBLE CROSS SECTIONS IN THE PEAK.

Table 2

No description provided.


Inclusive $D$ and $D^*$ Production in $e^+ e^-$ Annihilation at 29-{GeV}

The HRS collaboration Ahlen, S.P. ; Akerlof, C. ; Baranko, G. ; et al.
Phys.Rev.Lett. 51 (1983) 1147, 1983.
Inspire Record 191536 DOI 10.17182/hepdata.20523

Inclusive production of (D0, D¯0) and D± mesons have been observed in e+e− annihilation at 29 GeV. The signals correspond to R values of R(D0+D¯0)=3.25±1.2 and R(D++D−)=1.35±0.6. D*± production is also observed via the process D*+→D0π+ and its charge conjugate. The D and D* production rates are compared.

7 data tables
Table 1

EXTRAPOLATION TO ALL Z.

Table 2

EXTRAPOLATION TO ALL Z.

Table 3

EXTRAPOLATION TO ALL Z.

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