Usov, Yu.A.
E+ E- Scattering
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Search for new phenomena using single photon events in the DELPHI detector at LEP

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.
Z.Phys.C 74 (1997) 577-586, 1997.
Inspire Record 415746 DOI 10.17182/hepdata.41128

Data are presented on the reaction e+e− → γ + no other detected particle at centre-of-mass energies of 89.48, 91.26 and 93.08 GeV. The cross-section for this reaction is related directly to the number of light neutrino generations which couple to the Z° boson, and to several other possible phenomena such as the production of excited neutrinos, the production of any invisible ‘X’ particle, and the magnetic moment of the tau neutrino. Based on the observed number of single photon events, the number of light neutrinos that couple to the Z° is measured to be Nv = 2.89 ± 0.38. No evidence is found for anomalous production of energetic single photons, and upper limits at 95% confidence level are determined for excited neutrino production (BR < 4 − 8 × 10−6 depending on its mass), production of an invisible ‘X’ particle (σ, < 0.1 pb for masses below 60 GeV), and the magnetic moment of the tau neutrino (< 5.1 × 10-6 μB).

3 data tables
Table 1

No description provided.

Table 2

Limit on an anomalous magnetic moment for tau-neutrino from '1GAMMA + nothing' events. Magnetic moment in Bohr magnetons.

Table 3

Here UNSPEC is invisible particle.


rivet Analysis
The Measurement of R in e+ e- annihilation at center-of-mass energies between 7.2-GeV and 10.34-GeV

Blinov, A.E. ; Blinov, V.E. ; Bondar, A.E. ; et al.
Z.Phys.C 70 (1996) 31-38, 1996.
Inspire Record 364141 DOI 10.17182/hepdata.14321

The total cross section of the processe+e− →hadrons has been measured in the center-of-mass energy range between 7.25 and 10.34 GeV using the MD-1 detector at the VEPP-4 collider. The ratioR=σ(e+e− →hadrons)/σ(e+e− →μ+μ−) was found to be constant in this energy range with the average value of 3.58±0.02±0.14.

2 data tables
Table 1

Statistical errors only.

Table 2

Mean value of R in the range 7.25 to 10.34 GeV.


rivet Analysis
Measurement of inclusive Lambda production in electron - positron interactions at the upsilon energies

Blinov, A.E. ; Blinov, V.E. ; Bondar, A.E. ; et al.
Z.Phys.C 62 (1994) 367-370, 1994.
Inspire Record 362599 DOI 10.17182/hepdata.14205

Using the MD-1 detector at the VEPP-4e+e− strorage ring we have measured the inclusive Λ and370-1 production rates in direct Γ(1S) decays

4 data tables
Table 1

Lambda x spectrum in direct upsilon(1S) decay.

Table 2

Lambda multiplicity in direct upsilon(1S) decays.

Table 3

Lambda multiplicity in surrounding continuum.

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The search for narrow resonances in the reaction e+ e- ---> hadrons at center-of-mass energy range between 7.23-GeV and 10.34-GeV

Blinov, A.E. ; Blinov, V.E. ; Beilin, M.V. ; et al.
Z.Phys.C 49 (1991) 239-243, 1991.
Inspire Record 316888 DOI 10.17182/hepdata.15083

The results of a search for narrow resonances ine+e− annihilation at centre-of-mass energies between 7.23 and 10.34 GeV are presented. The experiment was performed using the MD-1 detector at the VEPP-4 storage ring. The total luminosity integral of 16 pb−1 was taken. There is no evidence that new states exist. The upper limits on the leptonic widthΓee of possible resonances are less, by a factor of 10–80, than theΓee for the ϒ(1S) meson.

1 data table
Table 1

Average R value (excluding upsilon region).


E+ E- PAIR PRODUCTION BY A SYNCHROTRON RADIATION PHOTON ON A COUNTER BEAM ELECTRON. (IN RUSSIAN)

Blinov, A.E. ; Bondar, A.F. ; Bukin, A.D. ; et al.
Yad.Fiz. 45 (1987) 1008-1014, 1987.
Inspire Record 256613 DOI 10.17182/hepdata.17424

None

3 data tables
Table 1

Axis error includes +- 2/2 contribution (Error in counter efficiency determination).

Table 2

Electron momentum distribution.

Table 3

Electron-positron pairs mass distribution.


OBSERVATION OF THE PROCESS E+ E- ---> GAMMA GAMMA GAMMA GAMMA

Vasserman, I.B. ; Golubev, V.B. ; Dolinsky, S.I. ; et al.
JETP Lett. 44 (1986) 634-637, 1986.
Inspire Record 241072 DOI 10.17182/hepdata.16909

None

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Results of the experiments from the neutral detector at the VEPP-2M storage ring in the energy region 2E$_{0}$ = 1.05 - 1.40 GeV

Dolinski, S.I. ; Druzhinin, V P ; Dubrovin, M S ; et al.
IYAF-85-98, 1985.
Inspire Record 1393709 DOI 10.17182/hepdata.982

None

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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RECENT RESULTS OF EXPERIMENTS WITH THE NEUTRAL DETECTOR AT VEPP-2M

Druzhinin, V.P. ; Dubrovin, M.S. ; Eidelman, S.I. ; et al.
IYF-84-93, 1984.
Inspire Record 202875 DOI 10.17182/hepdata.37143

None

1 data table
Table 1

'AXION' IS NEUTRAL BOSON WHICH HAS MASS < 200 MEV. IT IS ASSUMED THAT NEITHER THIS BOSON NOR THE PRODUCTS OF ITS DECAY ARE DETECTED.


PRELIMINARY RESULTS FROM THE NEUTRAL DETECTOR AT VEPP-2M

Bukin, A.D. ; Vasserman, I.B. ; Vorobev, P.V. ; et al.
IYF-83-80, 1983.
Inspire Record 192041 DOI 10.17182/hepdata.37136

None

1 data table
Table 1

Axis error includes +- 0.0/0.0 contribution (?////).


High Precision Measurement of the $\Upsilon$ Meson Mass

Artamonov, A.S. ; Baru, S.E. ; Blinov, A.E. ; et al.
Phys.Lett.B 118 (1982) 225, 1982.
Inspire Record 178785 DOI 10.17182/hepdata.37137

A high precision measurement of the υ-meson mass has been performed at the storage ring VEPP-4 using the MD-1 detector. The resonance depolarization method has been used for the absolute calibration of the beam energy that allowed to improve the accuracy of υ-mass measurement by a factor of ten. The following mass value has been obtained: M = 9459.7 ± 0.6 MeV.

1 data table
Table 1

No description provided.