Nucl.Phys.A

The momentum spectrum of protons emitted at small angles in the stripping reaction d + 12 C → p + X has been measured at a deuteron momentum of 8.9 GeV/ c . The data are described in the framework of the Glauber-Sitenko theory using the hybrid model of the deuteron wave function which includes a six-quark state. The parameters of this state are determined. A shoulder in the spectrum has been observed in the proton momenta region which kinematically corresponds to the production of a dibaryon resonance with a mass from 2.0 to 2.2 GeV.

Nucl. Instrum. Meth.

We describe a three-arm scintillation spectrometer used for reaction mechanism studies of proton-nucleus collisions at medium energies. The arrangement of the detector telescopes and the electronic scheme are presented. Special attention is paid to the separation of true triple coincidence events from different types of random events.

Teor.Mat.Fiz.

J.Phys.G

The 12C(p,pα)8Be reaction with large momentum transfer at energies of about 700 MeV has been studied. Three Feynman diagrams, i.e. heavy stripping, single pN scattering and one-pion exchange, have been used to describe the p(4N) → pα quasi-free interaction. Within the framework of the translationally invariant shell model, it is shown that the contribution of transitions with rearrangement of the knocked-out cluster internal states to the reaction cross section is highly sensitive to the quasi-free interaction mechanism and can be considerable.

Nucl. Instrum. Meth.

Results of studies of a position-sensitive scintillation counter are presented. The coordinates of tracks in the counter have been calculated from the centre of gravity of light intensity in the scintillator. The light intensity distribution has been measured by a system of strip light guides. The accuracy in localization of the track coordinates of electrons from a 106 Ru radioactive source is 3.0 mm. When the tracks are imitated by a collimated light diode (the slit width is 0.8 mm), the accuracy in determining the coordinate of the light source is 1.3 mm. Studies of the form of a light flash in the scintillator from the 106 Ru particles, the collimated light diode and cosmic rays are presented.