2018 Impact factor 2.481
Hadrons and Nuclei


Eur. Phys. J. A 12, 69-85 (2001)

Polarization observables in ($\overrightarrow\gamma,\overrightarrow{N} N$) reactions

C. Giusti and F.D. Pacati

Dipartimento di Fisica Nucleare e Teorica, Università di Pavia and INFN, Sezione di Pavia, Pavia, Italy

giusti@pv.infn.it
pacati@pv.infn.it

(Received: 7 June 2001 / Revised version: 6 September 2001 Communicated by Th. Walcher)

Abstract
The formalism of ($\overrightarrow\gamma,\overrightarrow{N} N$) reactions is given where the incident photon is polarized and the outgoing-nucleon polarization is detected. Sixteen structure functions and fifteen polarization observables are found in the general case, while only eight structure functions and seven polarization observables survive in coplanar kinematics. Numerical examples are presented for the 16O($\gamma,np$) and 16O($\gamma,pp$) reactions. The transitions to the ground state of 14C and 14N are calculated in a model where realistic short-range and tensor correlations are taken into account for the np pair, while short-range and long-range correlations are included in a consistent way for pp pairs. The effects of the one-body and two-body components of the nuclear current and the role of correlations in cross-sections and polarizations are studied and discussed.

PACS
25.20.Lj - Photoproduction reactions.
24.70.+s - Polarization phenomena in reactions.

© Società Italiana di Fisica, Springer-Verlag 2001