Date

Experimental study of four-prong events in proton proton interactions at 13.1 gev/c

Le Guyader, J. ; Sene, M. ; Ginestet, J. ; et al.
Nucl.Phys.B 35 (1971) 573-591, 1971.
Inspire Record 75410 DOI 10.17182/hepdata.33033

Approximately 21 000 four-prong pp interactions at 13.1 GeV/ c have been studied using the CERN 2m hydrogen bubble chamber. The following reactions have been analyzed pp→ppπ + π − (1) pp→ppπ + π − π 0 (2) pp→ppπ + π + π − (3) The Δ-production is the dominant feature. We also observed the pππ decay of the N ∗ (1470) and N ∗ (1690). The ϱis weakly produced in the three reactions. The η and the α are observed in the reaction (2) and the presence of a ω isobar is discussed. Then the kinematical characteristics of the final particles are described.

2 data tables

NORMALIZED TO A TOTAL CROSS SECTION OF 39.6 +- 0.2 MB.

RESONANCE PRODUCTION ESTIMATED BY CUTS WITH MONTE-CARLO AND HAND-DRAWN PHASE SPACE DISTRIBUTIONS.


Production of Dimuons in 16-GeV/c pi p Interactions

Bunnell, K. ; Duong-van, Minh ; Kogan, E. ; et al.
Phys.Rev.Lett. 40 (1978) 136, 1978.
Inspire Record 121404 DOI 10.17182/hepdata.20920

A clear, prompt dimuon signal has been observed in a low-statistics streamer-chamber experiment with 16-GeV/c πp interactions. The good mass resolution makes it possible to identify the contributions from ρ and ω decays and η and ω Dalitz decays. An excess of events is observed in the mass region ∼400-600 MeV which is not accounted for by the above-mentioned decays.

1 data table

The data with PI+- beam obtained from the combination of PI+ and PI- beams.


Inclusive Electron Production in Multiprong Events Produced by $e^+ e^-$ Annihilation

Feller, J.M. ; Litke, A. ; Madaras, R. ; et al.
Phys.Rev.Lett. 40 (1978) 1677, 1978.
Inspire Record 129962 DOI 10.17182/hepdata.38080

We have measured inclusive electron production in multiprong events produced by e+e− annihilation in the center-of-mass energy range 3.9-7.4 GeV. We find the electron momentum spectra are consistent with the electrons coming mainly from decays of charmed particles, with a smaller contribution from decays of the τ lepton. From our data we calculate the average branching ratio for charmed particles to decay into an electron plus additional particles to be (8.2±1.9)%.

1 data table

No description provided.


Production Characteristics of the F Meson

The DASP collaboration Brandelik, R. ; Braunschweig, W. ; Martyn, H.U. ; et al.
Phys.Lett.B 80 (1979) 412-418, 1979.
Inspire Record 132410 DOI 10.17182/hepdata.27370

Inclusive cross sections of η production by e + e - annihilation for c.m. energies between 4.0 and 5.0 GeV are presented. The η production is shown to be correlated with the production of a weakly decaying particle, indicating that its main source is F production. At the 4.42 GeV resonance it is correlated with a low energy photon, suggesting F F ∗ or F ∗ F ∗ production. A mass determination of the F is made at 4.42 GeV using the F → ηπ decay channel.

1 data table

NUMERICAL VALUES MEASURED FROM GRAPH IN PREPRINT. A CHARM MODEL (METHOD 2) GAVE CONSISTENT RESULTS FOR BACKGROUND SEPARATION.


Measurement of Inclusive $\eta$ Production in $e^+ e^-$ Interactions Near Charm Threshold

Partridge, Richard ; Peck, C. ; Porter, F. ; et al.
Phys.Rev.Lett. 47 (1981) 760, 1981.
Inspire Record 165255 DOI 10.17182/hepdata.3280

We have measured the inclusive cross section for η production in e+e− interactions near charm threshold using the Crystal Ball detector. No pronounced structure in the energy dependence is observed. By comparing cross sections above and below charm threshold we obtain the limits (90% confidence limit): R(e+e−→FF¯X)RB(F→ηx)<0.15−0.32 (for Ec.m. from 4.0 to 4.5 GeV), RB(D→ηx)<0.13. Our results are inconsistent with a previous report of a large energy dependence of the η cross section ascribed to the crossing of the FF* and F*F* production thresholds.

7 data tables

Axis error includes +- 0.0/0.0 contribution (?////DECAY PI0 --> 2GAMMA//RES-DEF(RES=ETA,BACK=CORRECTED,DEF=340 < M( 2GAMMA ) < 800 MEV)//DECAY-BR(BRN=ETA --> 2GAMMA,BR=38 PCT)).

THE 4.028 GEV DATA ARE NOT INCLUDED IN THE 4.005-4.082 GEV BIN. Axis error includes +- 0.0/0.0 contribution (?////DECAY PI0 --> 2GAMMA//RES-DEF(RES=ETA,BACK=CORRECTED,DEF=340 < M( 2GAMMA ) < 800 MEV)//DECAY-BR(BRN=ETA --> 2GAMMA,BR=38 PCT)).

AT FIXED ENERGIES.

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Observation of Semileptonic Decays of Charmed Baryons

Vella, E. ; Trilling, G. ; Abrams, G.S. ; et al.
Phys.Rev.Lett. 48 (1982) 1515, 1982.
Inspire Record 176986 DOI 10.17182/hepdata.19674

Direct electrons are observed in baryon events produced in e+e− annihilation at center-of-mass energies above the ΛcΛ¯c threshold. These events are attributed to charmed-baryon pair production and subsequent Λc semileptonic decay. Various semileptonic branching ratios of the Λc are determined, including B(Λc→e+X)=(4.5±1.7)%.

2 data tables

ELECTRON-BARYON RATIO ABOVE AND BELOW LAMBDA/C THRESHOLD.

No description provided.


INCLUSIVE PHOTOPRODUCTION OF pi0 AND eta0 MESONS FOR PHOTONS IN THE 100-GeV ENERGY RANGE

Breakstone, A.M. ; Cheng, D.C. ; Dorfan, D.E. ; et al.
Phys.Rev.Lett. 51 (1983) 1617, 1983.
Inspire Record 13620 DOI 10.17182/hepdata.20521

Inclusive distributions are presented for final-state π0 and η0 mesons produced in γp interactions. For photon energies from 50 to 130 GeV, both cross sections scale for fractional momenta xF>~0.30. The average transverse momentum for both mesons is approximately constant with energy and equal to 0.51±0.05 GeV/c at large xF. The η0π0 ratio similarly rises from 0.07±0.03 at xF=0.38 to 0.30±0.09 at xF=0.90. The π0 distributions are in good agreement with those seen in the scattering of highly virtual incident photons.

1 data table

No description provided.


Limit on the B ---> u Coupling from Semileptonic B Decay

The CLEO collaboration Chen, A. ; Goldberg, M. ; Horwitz, N. ; et al.
Phys.Rev.Lett. 52 (1984) 1084, 1984.
Inspire Record 199380 DOI 10.17182/hepdata.20474

We have used the momentum spectrum of leptons produced in semileptonic B-meson decays to set a 90%-confidence-level upper limit on Γ(b→ulν)Γ(b→clν) of 4%. We also measure the semileptonic branching fractions of the B meson to be (12.0±0.7±0.5)% for electrons and (10.8±0.6±1.0)% for muons.

2 data tables

No description provided.

No description provided.


Measurement of the Branching Ratio for $\Upsilon^\prime$-prime $\to \mu \mu$

Kaarsberg, T. ; Lee-Franzini, Juliet ; Lovelock, D.M.J. ; et al.
Phys.Rev.D 35 (1987) 2265, 1987.
Inspire Record 230842 DOI 10.17182/hepdata.23382

Using the CUSB-II detector at the Cornell Electron Storage Ring, we have measured Bμμ, the branching fraction into muons, of the Υ’’ meson. We find Bμμ(Υ’’)=(1.53±0.33±0.21)%, from which the Υ’’ total decay width is 25.5±5.0 keV. From this result we obtain αs=0.170−0.012+0.015, ΛMS¯=148−39+56 MeV. (MS¯ denotes the modified minimal-subtraction scheme).

1 data table

No description provided.


Inclusive $\pi^0$ and $\eta$ Meson Production in Electron Positron Interactions at $\sqrt{s}=10$-{GeV}

The ARGUS collaboration Albrecht, H. ; Glaser, R. ; Harder, G. ; et al.
Z.Phys.C 46 (1990) 15, 1990.
Inspire Record 278933 DOI 10.17182/hepdata.15301

We report on a high statistics study of π0 and η production in continuum events and in direct decays of the Γ(1S) and Γ(2S) resonances. The measured production rates per event are\(\left\langle {n_{\pi ^0 } } \right\rangle\)=3.22 ± 0.07 ± 0.31 (3.97 ± 0.23 ± 0.38) and 〈nη〉=0.19 ± 0.04 ± 0.04 (0.40 ± 0.14 ± 0.09) for continuum events (direct Γ(1S) decays).

6 data tables

First data point in table is from the continuum at sqrt(s)=9.46 GeV.

First data point in table is from the continuum at sqrt(s)=9.46 GeV.

PI0 spectrum in the continuum.

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