Nucleon Polarizabilities and Spin Sum-rules

Sam Hoblit

Brookhaven National Laboratory

Polarizabilities measure the strengths of transient dipole moments induced in the nucleon by the electromagnetic field of the photon during Compton scattering and describe the dynamical rearrangement of the constituent charges, magetic moments and spins. Unpolarized photon scattering has been used at several laboratories to study the six polarizabilities and the current status will be reviewed. Additional sensitivity to both the proton and neutron spin polarizabilities can be achieved through double polarization experiments, where both the incoming photon and target nucleon are polarized. The program of double polarization experiments at LEGS will be outlined.