Nuclear polarization and signs of quadrupole moments at high spins

The measurement of the sign of the electric quadrupole moment of an isomeric level via a PAD measurement requires the nuclear ensemble to be polarized. A recent development of a tilted multifoil technique for polarization of high spin reaction products makes such experiments possible. The need for measurements of signs of quadrupole moments of high spin isomers is discussed and two recent experiments studying the 54Fe(10+) and the 144Gd(10+) isomers are reviewed. The sign of the deformation was found to be positive for 54Fe(10+) and negative for 144Gd(10+) in agreement with expectation