Neutral Detector (ND) 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(Tl) scintillation counters.

List of published analyses

Radiative decays

Rare decays of the , , and mesons S.I. Dolinsky et al., Sov. J. Nucl. Phys. 48 (1988) 277. V. B. Golubev et al., Sov. J. Nucl. Phys. 44 (1986) 409.

Search for rare decays V. B. Vasserman et al., Sov. J. Mod. Phys. 48 (1988) 480.

V. M. Aulchcnko et al., Preprini INP 87-90 (Novosibirsk, 1987). light scalars and in -meson radiative decays

Non-resonant electron-positron annihilation into hadrons

A. D. Bukin et al., Sov. J. Nucl. Phys. 50 (1989) 621. V. M. Aulchenko et al., Preprint INP 86-106 (Novosibirsk, 1987).

Test of QED processes V. P. Druzhinin et al., Preprint INP 85-98 (Novosibirsk, 1985).V. M. Aulchcnko et al., Preprint INP 86-173 (Novosibirsk, 1986).

(virtual Compton scattering) V. B. Golubev et al., Sov. J. Nucl. Phys. 41(1985) 752.

Analyses of other processes Measurement of the ω-meson parameters Upper limits on electron width of scalar and tensor mesons , , , , and P. V. Vorobyov et al., Sov. J. Nucl. Phys. 48 (1988) 436. V. P. Druzhinin et al., Preprint INP 85-97 (Novosibirsk, 1985). Search for V. B. Golubev et al., Sov. J. Nucl. Phys. 45 (1987) 622. I. B. Vasserman et al., JETP Lett. 43(1986) 588. V. M. Aulchenkoet al., JETP Lett. 45 (1987) 145.

Detector

Based on goals of the physics program the ND consist of

Electromagnetic calorimeter 168 rectangular NaI(Tl) scintillation counters total mass of NaI(Tl) 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 (shower) 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. The Review of Particle Physics, K. Nakamura et al. (Particle Data Group), J. Phys. G 37, 075021 (2010)

See also

References

External links Budker Institute of Nuclear Physics (BINP) VEPP-2M NOVOSIBIRSK-ND experiment record on INSPIRE-HEP