Adam, W.
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Evidence for the tau --> Neutrino rho pi Decay Mode

The PLUTO collaboration Alexander, G. ; Criegee, L. ; Dehne, H.C. ; et al.
Phys.Lett.B 73 (1978) 99-104, 1978.
Inspire Record 122092 DOI 10.17182/hepdata.27462

Annihilation of e + e − into final states with a single electron has been studied with the PLUTO detector at the DORIS storage ring at CMS energies from 3.6 to 5 GeV. In the sample of 4-prong events without any detected photon we observe 21 events which we assign to the reaction e + e − → τ + τ − → νν e + νϱ 0 π . We obtain a branching ratio for τ + → νϱ 0 π + of 0.050 ± 0.015 with an overall systematic uncertainty of 30%. The data are consistent with the ϱπ coming from an A 1 meson.

1 data table
Table 1

No description provided.


Inclusive eta Production at Large Transverse Momenta

Donaldson, G.J. ; Gordon, H.A. ; Lai, K.-W. ; et al.
Phys.Rev.Lett. 40 (1978) 684, 1978.
Inspire Record 122477 DOI 10.17182/hepdata.20917

We have measured the ratio of inclusive production of η to π0 at transverse momenta above 1.5 GeV/c. Results are presented for various meson and proton beams with momenta of 100, 200, and 300 GeV/c incident upon a hydrogen target. The ηπ0 production ratio is found to be independent of incident beam momentum and of the transverse and longitudinal momenta of production. The ratio for pion- and proton-induced reactions is 0.44 ± 0.05; for kaons, it is 0.74 ± 0.12.

11 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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The Cross-Section for the Production of Massive electron Pairs and the Upsilon (9.5-GeV) in Proton Proton Collisions at the CERN ISR

Cobb, J.H. ; Iwata, S. ; Palmer, R.B. ; et al.
Phys.Lett.B 72 (1977) 273-277, 1977.
Inspire Record 122577 DOI 10.17182/hepdata.27504

Measurements of the cross section for the production of electron pairs with invariant masses between 4 and 8.7 GeV are presented as a function of the centre-of-mass energy ( s = 28 to s = 62 GeV ) of the colliding proton beams. A significant excess of events is observed in the region 8.7 to 10.3 GeV; these are ascribed to the ϒ(9.5 GeV) resonances and estimates of the production cross sections are given.

2 data tables
Table 1

Axis error includes +- 40/40 contribution (Due to the uncertainty in efficiency).

Table 2

Axis error includes +- 40/40 contribution (Due to the uncertainty in efficiency).


Experimental Limits on Heavy Lepton Production by Neutrinos

Cnops, A.M. ; Connolly, P.L. ; Kahn, S.A. ; et al.
Phys.Rev.Lett. 40 (1978) 144-146, 1978.
Inspire Record 121918 DOI 10.17182/hepdata.37905

We present upper limits on the production of heavy leptons (L±) by neutrinos via the process νμ+Ne→L±+⋯, L±→e±+ν+ν¯. These limits imply that the L− and L+, if they couple in full strength to νμ, are heavier than 7.5 and 9 GeV, respectively. They also imply that the coupling strength νμ to the recently discovered 1.9-GeV heavy lepton τ is less than 0.025 of the normal νμ−μ coupling.

1 data table
Table 1

No description provided.


Hadron Production by Virtual Photons in the Quark Fragmentation Region

Scarr, J.M. ; Chen, C.K. ; Knowles, J. ; et al.
Nucl.Phys.B 135 (1978) 224-236, 1978.
Inspire Record 122308 DOI 10.17182/hepdata.35139

We have measured the inclusive electroproduction of positive and negative hadrons in the quark fragmentation region using the streamer chamber at DESY. Data are presented in terms of the variable z p = p / v in the kinematic region 1.8 < W < 2.8 GeV and 0.3 < Q 2 < 1.4 GeV 2 . The positive hadron distributions contain a strong proton component. After subtraction of the proton component and elastic rho events, the distribution (1/ σ tot ) d σ /d z p for positive and negative hadrons agrees well with the corresponding distribution from e + e − annihilation (DORIS data). This behaviour supports the validity of the quark-parton model at surprisingly low Q 2 and W .

1 data table
Table 1

No description provided.


Study of K* (1780) in the Reaction K- p --> K- pi+ n at 6-GeV/c

Chung, S.U. ; Etkin, A. ; Flaminio, V. ; et al.
Phys.Rev.Lett. 40 (1978) 355-358, 1978.
Inspire Record 122473 DOI 10.17182/hepdata.20913

We observe a K−π+ state at 1786 ± 8 MeV with a width 95 ± 31 MeV in the reaction K−p→K−π+n at 6 GeV/c, from an experiment carried out at the Brookhaven National Laboratory multiparticle spectrometer.

1 data table
Table 1

ERROR INCLUDES SYSTEMATIC NORMALIZATION UNCERTAINTY.


Inclusive Double Charge Exchange $\pi^-$ Production at 100 GeV/c

Cutts, D. ; Dulude, R. ; Lanou, R.E. ; et al.
Phys.Rev.Lett. 40 (1978) 141, 1978.
Inspire Record 121767 DOI 10.17182/hepdata.20919

Measurements of inclusive cross sections at 100 GeV/c are presented for the double-charge-exchange reactions a+p→π−X with a=π, K, or p. The measurements covered a kinematic range in the Feynman x variable of 0.3<~x<~0.9 at transverse momenta of 0.3 and 0.5 GeV/c. A model summing the contributions from resonance production and from inclusive central-region π− production is used to fit the data and demonstrates the importance of resonance production via one-pion exchange for large values of the Feynman x.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Measurement of the Line Reversed Reactions anti-p p --> pi- rho- and pi- p --> p rho- at 6-GeV/c

Green, D.R. ; Edelstein, R.M. ; Halpern, H.J. ; et al.
Phys.Rev.Lett. 39 (1977) 1243-1246, 1977.
Inspire Record 126174 DOI 10.17182/hepdata.21005

Differential cross sections and density-matrix elements in ρ− decay have been measured at 6 GeV/c for p¯p→π+ρ− and its line-reversed partner π−p→pρ− in the range tmin>t>−1.5 (GeV/c)2. The reactions satisfy line-reversal symmetry and the ρ− decay is consistent with isotropy for −t≲0.5 (GeV/c)2. For −t≳0.5 (GeV/c)2, the differential cross sections show a weaker t dependence, and the decays become anisotropic.

2 data tables
Table 1

No description provided.

Table 2

FROM ROUGHLY EQUAL NUMBERS OF RHO- EVENTS AND BACKGROUND (CONSISTENT WITH ISOTROPY FOR BOTH REACTIONS).


Study of Photons Produced Simultaneously with the J/psi Particles at the CERN Intersecting Storage Rings

Cobb, J.H. ; Iwata, S. ; Palmer, R.B. ; et al.
Phys.Lett.B 72 (1978) 497-499, 1978.
Inspire Record 122488 DOI 10.17182/hepdata.50369

As a part of the study of the inclusive production of electron pairs in pp collisions at the CERN Intersecting Storage Rings (ISR), a search has been performed for additional photons accompanying J/ψ particles. The results suggest that (43±21)% of the J/ψ's are produced via the photonic decay of one of the χ(3.5) states.

1 data table
Table 1

The cross section times branching ratio.


Meson Production by Delta Exchange in pi- p Interactions at 4-GeV/c

Scharre, D.L. ; Chapman, J.W. ; Ely, R.P. ; et al.
Phys.Rev.D 17 (1978) 2853, 1978.
Inspire Record 121388 DOI 10.17182/hepdata.24432

A streamer-chamber spectrometer is triggered by fast forward protons from 4-GeV/c π−p interactions at the Bevatron. Meson-resonance production in the backward, Iu=32 exchange reactions π−p→pM− are studied, where M− refers to π−, ρ−, A1−, A2−, and B−. Elastic scattering and ρ− production are observed and discussed in detail. No backward A1−, A2−, or B− production is observed at the level of approximately 5 βb.

5 data tables
Table 1

Axis error includes +- 15/15 contribution.

Table 2

No description provided.

Table 3

Axis error includes +- 15/15 contribution.

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