Hanhart, C
hep-ex
E+ E- Scattering
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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.


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.


rivet Analysis
Search for Narrow Resonances in e+ e- Annihilation Into Hadrons in the Mass Regions 1910-MeV-2545-MeV and 2970-MeV-3090-MeV

Bacci, C. ; Baldini-Celio, R. ; Bidoli, V. ; et al.
Phys.Lett.B 58 (1975) 481-483, 1975.
Inspire Record 100016 DOI 10.17182/hepdata.27776

We have searched for possible narrow resonances produced in e + e − annihilation at Adone, in the mass regions 1910–2545 MeV and 2970–3090 MeV. No evidence has been found for narrow resonances, within the sensitivity of the present work: we deduce an upper limit on the energy integrated resonant cross section of about 10% of the J/ψ(3100) corresponding value.

1 data table
Table 1

No description provided.


Multi-Hadronic Decays and Partial Widths of the J/psi (3100) Resonance Produced in e+ e- Annihilation at ADONE

Bacci, C. ; Baldini-Celio, R. ; Bozzo, M. ; et al.
Phys.Lett.B 58 (1975) 471-474, 1975.
Inspire Record 100017 DOI 10.17182/hepdata.27794

The reactions e + e − → hadrons and e + e + e − →e + e − have been studied at the J/gY (3100) resonance). The relative weights of the topological cross sections for fixed charged multiplicity are σ 2 =(32±5)%, σ 4 =(49±8)%, σ 6 =(18±3)%, and σ 8 =(1±0.6)%. The average pion multiplicities are 〈 n ch 〉=3.8±0.3 and 〈n π o 〉=3.1±0.8 . The decay widths are Γ e =(4.6±0.8) keV, Γ h =(59±24) keV, and Γ =(68±26) keV.

3 data tables
Table 1

CROSS SECTION AROUND RESONANCE.

Table 2

CROSS SECTION JUST BELOW J/PSI.

Table 3

MULTIPLICITY AT J/PSI.


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.


Azimuthal Asymmetry in Inclusive Hadron Production by e+ e- Annihilation

Schwitters, R. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 35 (1975) 1320, 1975.
Inspire Record 100683 DOI 10.17182/hepdata.21192

We have observed an azimuthal asymmetry in inclusive hadron production by e+e− annihilation at the center-of-mass energy s=7.4 GeV. The asymmetry is caused by the polarization of the circulating beams in the storage ring and allows separate determination of the transverse and longitudinal structure functions. We find that transverse production dominates for x>0.2 where x is the scaling variable 2ps.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


rivet Analysis
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.


Production of 4 pi+- and 6 pi+- by e+ e- Annihilation Between 2.4-GeV and 7.4-GeV

Jean-Marie, B. ; Abrams, G.S. ; Boyarski, A. ; et al.
SLAC-PUB-1711, 1976.
Inspire Record 108089 DOI 10.17182/hepdata.18658

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.