Author/Authors :
Bilger، نويسنده , , R and Brodowski، نويسنده , , W and Calén، نويسنده , , H and Clement، نويسنده , , H and Dunin، نويسنده , , V and Dyring، نويسنده , , J and Ekstr?m، نويسنده , , C and Fransson، نويسنده , , K and Greiff، نويسنده , , J and Gustafsson، نويسنده , , L and H?istad، نويسنده , , B and Johanson، نويسنده , , J and Johansson، نويسنده , , A and Johansson، نويسنده , , T and Kilian، نويسنده , , K and Koch، نويسنده , , I and Kullander، نويسنده , , S an، نويسنده ,
Abstract :
Low-energy spectator protons (ps) from quasi-free proton–neutron interactions on deuterium have been measured for the pd→dπ0ps and pd→pnπ0ps reactions at the CELSIUS storage ring of the The Svedberg Laboratory. The experiment used 320 MeV protons incident on a deuterium cluster-jet target. The spectator protons were detected inside the scattering chamber using a silicon detector system which is compatible with a high vacuum. The low target density allows the spectator proton emerge without undergoing significant secondary scattering. Its measurement is therefore a useful tag upon such reactions, allowing cross-sections for quasi-free reactions to be deduced at well-defined centre-of-mass energies. The comparison with the simulation for the pd→dπ0ps reaction shows that the energy dependence of the pn→dπ0 cross-section can be extracted near the threshold. The method greatly improves the experimental resolution achievable in quasi-free p–n reaction studies.
