# XX International Workshop on Deep-Inelastic Scattering and Related Subjects

26-30 March 2012
University of Bonn
Europe/Berlin timezone

## Spin structure of the "forward" nucleon charge-exchange reaction n + p ---> p + n and the deuteron charge-exchange breakup

28 Mar 2012, 14:15
20m
Lecture Hall, Institute for Physical Chemistry (University of Bonn)

### Lecture Hall, Institute for Physical Chemistry

#### University of Bonn

Diffraction and vector mesons/spin physics

### Speaker

Dr Valery Lyuboshitz (Joint Institute for Nuclear Research, Dubna, Russia)

### Description

The structure of the nucleon charge-exchange process n + p --> p + n is investigated basing on the isotopic invariance of the nucleon-nucleon scattering. Using the operator of permutation of the spin projections of the neutron and proton, the connection between the spin matrices, describing the amplitude of the nucleon charge-exchange process at zero angle and the amplitude of neutron elastic scattering on the proton in the "backward" direction, has been considered. Due to the optical theorem, the spin-independent part of the differential cross-section of the process n + p --> p + n at zero angle for unpolarized particles is expressed through the difference of total cross-sections of unpolarized proton-proton and neutron-proton scattering. Meantime, the spin-dependent part of this cross-section is proportional to the differential cross-section of the deuteron charge-exchange breakup d + p --> (pp) + n at zero angle at the deuteron momentum {\bf k}_d = 2{\bf k}_n ( {\bf k}_n is the initial neutron momentum ). Analysis shows that, assuming the real part of the spin-independent term of the "forward" amplitude of the process n + p --> p + n to be smaller or of the same order as compared with the imaginary part, in the wide range of neutron laboratory momenta k_n > 700 MeV/c the main contribution into the differential cross-section of the process n + p --> p + n at zero angle is provided namely by the spin-dependent term .

### Primary author

Dr Valery Lyuboshitz (Joint Institute for Nuclear Research, Dubna, Russia)

### Co-author

Dr Vladimir Lyuboshitz (Joint Institute for Nuclear Research, Dubna, Russia)

### Presentation materials

 Proceedings Slides