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Observation of a Resonance at 4.4-GeV and Additional Structure Near 4.1-GeV in e+ e- Annihilation

Siegrist, J. ; Abrams, G.S. ; Boyarski, A. ; et al.

Phys.Rev.Lett. 36 (1976) 700, 1976.

Inspire Record 108144 DOI 10.17182/hepdata.21093

We observe a resonancelike structure in the total cross section for hadron production by e+e− colliding beams at a mass of 4414 ± 7 MeV having a total width Γ=33±10 MeV. From the area under this resonance, we deduce the partial width to electron pairs to be Γee=440±140 eV. Further structure of comparable width is present near 4.1 GeV.

1 data table

Table 1

No description provided.

Preliminary Result of Frascati (ADONE) on the Nature of a New 3.1-GeV Particle Produced in e+ e- Annihilation

Bacci, C. ; Celio, R.Balbini ; Berna-Rodini, M. ; et al.

Phys.Rev.Lett. 33 (1974) 1408, 1974.

Inspire Record 90991 DOI 10.17182/hepdata.21293

We report on the results at ADONE to study the properties of the newly found 3.1-BeV particle.

1 data table

Table 1

No description provided.

Differential Cross-Sections of the Proton Compton Scattering in the Energy Between 450-MeV and 950-MeV

Toshioka, K. ; Chiba, M. ; Kato, S. ; et al.

Nucl.Phys.B 141 (1978) 364-378, 1978.

Inspire Record 120614 DOI 10.17182/hepdata.34955

The differential cross sections of the proton Compton scattering around the second resonance have been measured at a c.m. angle of 90° for incident photon energies between 450 MeV and 950 MeV in steps of 50 MeV, and at an angle of 60° for energies between 600 MeV and 800 MeV. The results show that the peak of the 2nd resonance agrees with that of the pion photoproduction process. We also calculated the proton Compton scattering based on unitarity and fixed- t dispersion relations. The calculation describes well the data of the cross section and the recoil proton polarization.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

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.

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.

The Discovery of a Second Narrow Resonance in e+ e- Annihilation

Abrams, G.S. ; Briggs, D. ; Chinowsky, William ; et al.

Phys.Rev.Lett. 33 (1974) 1453-1455, 1976.

Inspire Record 91611 DOI 10.17182/hepdata.21287

We have observed a second sharp peak in the cross section for e+e−→hadrons at a center-of-mass energy of 3.695±0.004 GeV. The upper limit of the full width at half-maximum is 2.7 MeV.

1 data table

Table 1

No description provided.

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.

Reaction $\pi^- p \to \eta n$ in the 15-{GeV}/$c$ to 40-{GeV}/$c$ Momentum Range

The Serpukhov-CERN collaboration Apel, W.D. ; Augenstein, K.H. ; Bertolucci, E. ; et al.

Nucl.Phys.B 152 (1979) 1, 1979.

Inspire Record 133409 DOI 10.17182/hepdata.41487

A high-statistics measurement of the reaction π − p→ η n; η →2 γ has been performed at the 70 GeV Serpukhov accelerator for 15, 20, 25, 30 and 40 GeV/ c incident pion momentum using the NICE set-up with its associated 648-channel hodoscope spectrometer for γ-ray detection. It is found that the spin-flip and non-spin-flip amplitudes can be parametrized, for small | t |, as exponentials with the same slopes to within a few percent. For | t | ≳ 1 (GeV/ c ) 2 there is a break in the differential cross section. In addition, the A 2 effective trajectory deviates markedly for | t | ≳ 1 GeV/ c ) 2 from the linear behaviour valid for smaller | t |.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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