Green, J.
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A Study of D* Production in High-Energy $\gamma$ p Interactions

Sliwa, K. ; Appel, J.A. ; Biel, J. ; et al.
Phys.Rev.D 32 (1985) 1053-1060, 1985.
Inspire Record 194636 DOI 10.17182/hepdata.23561

We have studied D* production mechanisms using data from a photoproduction experiment at the Fermilab Tagged Photon Spectrometer. A large sample of charged D*’s was selected via the clean signature of the cascade decay D*→D0π+ and subsequently D0→K−π+ or D0→K−π+π0. The cross section for the process γp→(D*++anything)p at an average energy of 105 GeV was measured to be 88±32 nb. Only (11±7)% of D*’s were found to be consistent with being accompanied solely by a D¯* or a D¯; the remaining events contain additional particles. The distribution of the production angle of the D* in the photon-fragmentation-system center of mass is strongly anisotropic and consistent with the form f(θ*)=cos4θ*. We set a limit on the associated-production-process cross section σ(γp→(D¯*−+anything)Λc) x)<60 nb (90% C.L.).

2 data tables
Table 1

No description provided.

Table 2

No description provided.


rivet Analysis
The Total Cross-section for Electron - Positron Annihilation Into Hadron Final States in the $\Upsilon$ Energy Region

The CLEO collaboration Giles, R. ; Hassard, J. ; Hempstead, M. ; et al.
Phys.Rev.D 29 (1984) 1285, 1984.
Inspire Record 193577 DOI 10.17182/hepdata.23768

We report measurements made with the CLEO detector at the Cornell Electron Storage Ring (CESR) of the total cross section for e+e−→hadrons at the ϒ(1S), ϒ(2S), and ϒ(3S), and in the nearby nonresonant continuum. We find R=3.77±0.06 (statistical) ± 0.24 (systematic) for the ratio of the nonresonant hadronic cross section to the cross section for muon-pair production at a center-of-mass total energy W=10.4 GeV. For the leptonic decay widths Γee of the ϒ(1S), ϒ(2S), and ϒ(3S) we obtain 1.30±0.05±0.08, 0.52±0.03±0.04, and 0.42±0.04±0.03 keV, respectively.

1 data table
Table 1

No description provided.


Diffractive Production of $K^0_s K^0_s \pi^+ \pi^- \pi^-$ in $\pi^-N$ Interactions at 200-GeV/c

Chang, C.C. ; Davis, T.C. ; Diamond, R.N. ; et al.
Phys.Rev.D 29 (1984) 1888-1894, 1984.
Inspire Record 194648 DOI 10.17182/hepdata.23730

The diffractive dissociation of a 200-GeV/c π− beam into KS0KS0π+π−π− has been observed. The diffractive KS0KS0π+π−π− cross section is 1.59±0.78 μb. The ratio of the diffractive KS0KS0π+π−π− cross section to the diffractive KS0KS0π− cross section is 0.40±0.13, which is in good agreement with a diffractive-fragmentation-model prediction of 0.36. There is evidence for simultaneous production of K*− and K*+ in the diffractive KS0KS0π+π−π− sample. The K*+−KS0π−+ mass distribution shows an enhancement near 1.95 GeV.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Production and Muonic Decay of Heavy Quarks in e+ e- Annihilation at 34.5-GeV

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Z.Phys.C 22 (1984) 219, 1984.
Inspire Record 194775 DOI 10.17182/hepdata.16252

The production of prompt muons ine+e− annihilation has been studied at centre of mass energies near 34.5 GeV. The measured semi-muonic branching ratios ofb andc quarks areB(b»Xμv) =0.117±0.028±0.01 andB(c→Xμv)=0.082 ±0.012a−0.01+0.02. The fragmentation functions of heavy quarks are hard, =0.85a−0.12–0.07+0.10+0.02 and =0.77a−0.07–0.11+0.05+0.03. Limits have been set on flavour changing neutral current decays:B(b→Xµ+µ−) <0.02 andB(b→Xµ+µ− (95% confidence level).

1 data table
Table 1

THE VALUE OF ASYMMETRY WAS DETERMINED USING A SAMPLE OF PROMPT MUONS.


rivet Analysis
Observation of F Meson Production in High-energy $e^+ e^-$ Annihilation

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Phys.Lett.B 136 (1984) 130-134, 1984.
Inspire Record 194774 DOI 10.17182/hepdata.30586

Production of the F meson by e + e − annihilation at high energies has been obsrved in the ϕπ final state with a mass of 1.975 ± 0.009 ± 0.010 GeV and a width consistent with the mass resolution. The yield of F production times branching ratio relative to μ pair production is R F ( x ⩾ 0.3) B (F ± → ϕπ ± ) = 0.061 ± 0.012 ± 0.018.

2 data tables
Table 1

No description provided.

Table 2

CROSS BETWEEN X BRANCHING RATIO DETERMINATION. EXTRAPOLATION BELOW X=0.3 IS USED.


Properties of Charm Jets Produced in $e^+ e^-$ Annihilation Near 34-{GeV}

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Phys.Lett.B 135 (1984) 243-249, 1984.
Inspire Record 194050 DOI 10.17182/hepdata.30600

D ∗± production via e + e − → D ∗± X was studied at CM energies near 34 GeV. The charged particles produced in the hemisphere opposite to that of the D ∗ were used to investigate the fragmentation of charm jets. All spectra studied show a close similarity between the charm jet and the average jet obtained by summing over all quark flavours. The spectra of particles produced in the D ∗ hemisphere were used to study separately first rank and higher rank fragmentation.

2 data tables
Table 1

THE C-JET IS THE JET IN THE HEMISPHERE OPPOSITE TO THAT CONTAINING THE D* MESON. DIVISION IS MADE BY A PLANE PERPENDICULAR TO THE THRUST AXIS.

Table 2

No description provided.


Exclusive Production of Hadron Pairs at Large Momentum Transfer in Photon-photon Interactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Phys.Lett.B 137 (1984) 267-271, 1984.
Inspire Record 194772 DOI 10.17182/hepdata.30576

We report on the exclusive production of π, K and proton pairs from photon-photon interactions at momentum transfers | t |⩾1 GeV 2 . Using the PLUTO detector at the e + e − storage ring PETRA, we have observed 15 events in an integrated luminosity of 41.7 pb −1 . The data lie far below the expectations for point-like hadrons, and are in reasonable agreement with the QCD-based predictions of Brodsky and Lepage.

3 data tables
Table 1

THIS METHOD OF ANALYSIS OF THE OBSERVED RATIO OF HADRON TO MUON PAIRS, IS TIED TO THE SPECIFIC DETECTOR ACCEPTANCE, BUT HAS THE ADVANTAGE OF BEING VIRTUALLY INDEPENDENT OF THE HADRON MASSES.

Table 2

SEE COMMENT IN PREVIOUS TABLE.

Table 3

THIS METHOD OF ANALYSIS OF THE CROSS SECTION AT 90 DEG IN THE CM AS A FUNCTION OF PCM IS MORE EASILY COMPARED WITH THEORETICAL PREDICTIONS BUT MORE DEPENDENT ON THE SPECIFIC HADRON MASSES.


Observation of a Peak at 1.28-{GeV} in the $\eta \pi \pi$ System in the Reaction $\gamma p \to \eta \pi^+ \pi^- p$

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Nucl.Phys.B 242 (1984) 269-281, 1984.
Inspire Record 194474 DOI 10.17182/hepdata.33873

A peak is reported in the ηπ + π − system, produced in the reaction γ p→ ηπ + π − p, at a mass of 1.28 ± 0.01 GeV with a width of 0.08 ± 0.02 GeV. Possible spin-parity assignments for the peak are shown to be J π = 1 − , J π = 1 + or J π = 2 + and interpretations of these assignments are discussed.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Inclusive $\pi^0$ Production in 360-{GeV} $p p$ Interactions Using the European Hybrid Spectrometer

The EHS-RCBC collaboration Bailly, J.L. ; Bartl, W. ; Bruyant, F. ; et al.
Z.Phys.C 22 (1984) 119, 1984.
Inspire Record 193697 DOI 10.17182/hepdata.2106

The intermediate and forward gamma detectors of EHS are used to reconstructπ°'s produced by 360 GeV/cpp interactions in the Rapid Cycling Bubble Chamber (RCBC). Using thepp forwardbackward symmetry, the inclusiveπ° production cross section is obtainedσπ°=(132±11) mb. The averageπ° multiplicity is determined as a function of the charged particle multiplicity. The (1−x) dependence is given for differentpT regions.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Axis error includes +- 4/4 contribution.


Measurements of the a-Dependence of Deep Inelastic electron Scattering from Nuclei

Arnold, R.G. ; Bosted, Peter E. ; Chang, C.C. ; et al.
Phys.Rev.Lett. 52 (1984) 727, 1984.
Inspire Record 193846 DOI 10.17182/hepdata.20435

The deep-inelastic electron-scattering cross sections per nucleon σA for D, He, Be, C, A1, Ca, Fe, Ag, and Au were measured in the kinematic range 0.09<~x<~0.9 and 2<~Q2<~15 (GeV/c)2 with use of electrons with energies ranging from 8 to 24.5 GeV. The ratio σAσD is consistent with unity in the range 0.1

10 data tables
Table 1

THESE RATIOS ARE AVERAGED OVER Q**2.

Table 2

No description provided.

Table 3

No description provided.

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