ND experiment

Neutral Detector is a detector for particle physics experiments created by the team of physicists in the
Budker Institute of Nuclear Physics, Novosibirsk, Russia.
Experiments with the ND were conducted from 1982 to 1987 at the e⁺e⁻ storage ring VEPP-2M in the energy range 2E =.

Physics

At the beginning of 80s the leading cross sections of the electron-positron annihilation in the final states with charged particles were measured in the energy range 2E=0.5-1.4 GeV. Processes with the neutral particles in the final state were less studied. To investigate the radiative decays of the,, and mesons and other processes involving photons,, and mesons the ND
was constructed. Its distinguishing features are defined by the specially designed electromagnetic calorimeter based on NaI scintillation counters.
List of published analyses

Radiative decays
Rare decays of the,, and mesons
Search for rare decays
Non-resonant electron-positron annihilation into hadrons
Test of QED processes
Analyses of other processes
*Measurement of the ω-meson parameters
*Upper limits on electron width of scalar and tensor mesons,,,, and
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*Search for
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Detector

Based on goals of the physics program the ND consist of
Electromagnetic calorimeter

168 rectangular NaI scintillation counters
total mass of NaI is 2.6 t
solid angle coverage is 65% of 4π sr
minimum thickness is 32 cm or 12 radiation length
energy resolution for photons is σ/E = 4% /

Charged particle coordinate system

3 layers of coaxial cylindrical 2-d wire proportional chambers in the center of the detector
solid angle coverage is 80% of 4π sr
angular resolution is 0.5° in the azimuthal and 1.5° in the polar direction
surrounded by the 5-mm thick plastic scintillation counter for trigger

Flat coordinate 2-d wire proportional chambers

2 layers of flat 2-d wire proportional chambers.
angular resolution is 2° in the azimuthal and 3.5° in the polar direction for 0.5 GeV photons

Iron absorber & anti-coincidence counters

The electromagnetic calorimeter is covered by the 10-cm thick iron absorber and plastic scintillation anti-coincidence counters.

Results

Data collected with the ND experiment corresponds to the integrated luminosity 19 pb⁻¹.
Results of the experiments with ND are presented in Ref.,
and are included in the PDG Review.