Allison, John
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Evidence for anomalous lepton production in e+ e- annihilation.

Perl, Martin L. ; Abrams, G.S. ; Boyarski, A. ; et al.
Phys.Rev.Lett. 35 (1975) 1489-1492, 1975.
Inspire Record 100634 DOI 10.17182/hepdata.21164

We have found events of the form e++e−→e±+μ∓+missingenergy, in which no other charged particles or photons are detected. Most of these events are detected at or above a center-of-mass energy of 4 GeV. The missing-energy and missing-momentum spectra require that at least two additional particles be produced in each event. We have no conventional explanation for these events.

1 data table
Table 1

X IN RE INCLUDES TWO OR MORE UNDETECTED PARTICLES.


The Quantum Numbers and Decay Widths of the psi-prime (3684)

Luth, V. ; Boyarski, A. ; Lynch, H.L. ; et al.
Phys.Rev.Lett. 35 (1975) 1124-1126, 1975.
Inspire Record 100636 DOI 10.17182/hepdata.21229

Cross sections for e+e−→hadrons, e+e−, and μ+μ− near 3684 MeV are presented. The ψ(3684) resonance is established as having the assignment JPC=1−−. The mass is 3684 ± 5 MeV. The partial width for decay to electrons is Γe=2.1±0.3 keV and the total width is Γ=228±56 keV.

1 data table
Table 1

No description provided.


Charged-Particle Multiplicities in 100-GeV/c anti-p p Interactions

Ansorge, R.E. ; Bust, C.P. ; Carter, J.R. ; et al.
Phys.Lett.B 59 (1975) 299-302, 1975.
Inspire Record 2603 DOI 10.17182/hepdata.27765

Results are presented on the topological cross sections obtained for antiproton-proton interactions from an exposure of the Fermilab 30-inch bubble chamber to a 100 GeV/ c negative beam enriched in p 's. The p p inelastic cross section is found to be σ inel = 34.6 ± 0.4 mb, and the average inelastic charged particle multiplicity to be 〈 n 〉 = 6.74 ± 0.05.

3 data tables
Table 1

ERRORS ARE STATISTICAL ONLY EXCEPT FOR 2-PRONG CROSS-SECTIONS.

Table 2

EXPONENTIAL FIT TO ELASTIC T DISTRIBUTION TO CORRECT FOR AN APPARENT LOSS OF EVENTS AT SMALL -T.

Table 3

MOMENTS OF 100 GEV/C AP P MULTIPLICITY DISTRIBUTION.


The Quantum Numbers and Decay Widths of the psi (3095)

Boyarski, A. ; Breidenbach, Martin ; Bulos, F. ; et al.
Phys.Rev.Lett. 34 (1975) 1357, 1975.
Inspire Record 100657 DOI 10.17182/hepdata.21242

We present cross sections for e+e−→hadrons, e+e−, and μ+μ− near 3095 MeV. The ψ(3095) resonance is established as having an assignment JPC=1−−. The mass is 3095 ±4 MeV. The partial width to electrons is Γe=4.8±0.6 keV and the total width Γ=69±15 keV. Total rates and interference measurements for the lepton channels are in accord with μ−e universality.

1 data table
Table 1

No description provided.


Spin-Parity Analysis of Diffractive n --> p pi- and the Question of a Parity-Change Rule

Ansorge, R.E. ; Carter, J.R. ; Neale, W.W. ; et al.
Phys.Rev.D 13 (1976) 1835, 1976.
Inspire Record 99426 DOI 10.17182/hepdata.24786

A spin-parity analysis is performed of the low-mass (≤ 1.75 GeV/c2) pπ− system in diffractive np→(pπ−)p using new data at 13 GeV/c and 20 GeV/c. In the context of a Deck-plus-resonances model a good fit to the pπ− angular moments is found only if the Gribov-Morrison parity-change rule does not hold and spin states up to j=52 are included. In particular the presence of a considerable fraction of spin-parity ½− state is indicated.

1 data table
Table 1

DECK MODEL PLUS RESONANCES FIT TO DIFFRACTIVE EVENTS.


An Improved Upper Limit for Photoproduction of psi (3105) Near Threshold

Andrews, D.E. ; Harvey, John R. ; Lobkowicz, F. ; et al.
Phys.Rev.Lett. 34 (1975) 1134-1136, 1975.
Inspire Record 98255 DOI 10.17182/hepdata.21225

An improved upper limit for ψ photoproduction near threshold is presented.

1 data table
Table 1

The branching ratio for J/PSI --> E+ E- is taken as 0.06.


Search for Narrow Resonances in e+ e- Annihilation in the Mass Region 3.2-GeV to 5.9-GeV

Boyarski, A. ; Breidenbach, Martin ; Bulos, F. ; et al.
Phys.Rev.Lett. 34 (1975) 762, 1975.
Inspire Record 100594 DOI 10.17182/hepdata.21228

We have searched the mass region 3.2 to 5.9 GeV for evidence of narrow resonances in e+e−→hadrons. We find no evidence for any such resonances other than the ψ(3695) in this region with a sensitivity ranging from about 12 to 45% of the integrated cross section of the ψ(3695). The more stringent bounds apply to resonances of a few MeV width, while the looser bounds apply to resonances of up to 20 MeV width.

1 data table
Table 1

EXTREAMLY GOOD DATA, MUST BE ASCED FROM AUTHORS.


rivet Analysis
Total Cross-Section for Hadron Production by electron-Positron Annihilation Between 2.4-GeV and 5.0-GeV Center-Of-Mass Energy

Augustin, J.E. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 34 (1975) 764, 1975.
Inspire Record 100592 DOI 10.17182/hepdata.21227

The total cross section for hadron production by e+e− annihilation has been measured at center-of-mass energies between 2.4 and 5.0 GeV. Aside from the very narrow resonances ψ(3105) and ψ(3695), the cross section varies between 32 and 17 nb over this region with structure in the vicinity of 4.1 GeV.

2 data tables
Table 1

No description provided.

Table 2

MEAN CHARGED MULTIPLICITY. ERRORS ARE STATISTICAL ONLY.


Lambda p Interactions Below 24-GeV/c

Mount, R.P. ; Ansorge, R.E. ; Carter, J.R. ; et al.
Phys.Lett.B 58 (1975) 228-232, 1975.
Inspire Record 103555 DOI 10.17182/hepdata.27777

Λp interactions have been studied at momenta up to 24 GeV/ c using a new bubble chamber technique. We find that the Λp elastic cross section has fallen to approximately 6 mb at the highest momentum. Results are presented on Λ p→ Λ p π + π − for the first time above 5 GeV c .

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

ESTIMATE.

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Discovery of a Narrow Resonance in $e^+ e^-$ Annihilation

The SLAC-SP-017 collaboration Augustin, J.E. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 33 (1974) 1406-1408, 1974.
Inspire Record 91761 DOI 10.17182/hepdata.21247

We have observed a very sharp peak in the cross section for e+e−→hadrons, e+e−, and possibly μ+μ− at a center-of-mass energy of 3.105±0.003 GeV. The upper limit to the full width at half-maximum is 1.3 MeV.

1 data table
Table 1

No description provided.