Rise and Fall of the Spin Alignment in Deep-Inelastic Reactions

Both the magnitude and alignment of the transferred angular momentum in the reaction {sup 165}Ho + {sup 165}Ho have been measured as a function of Q value via continuum {gamma}-ray multiplicity and anisotropy techniques. Two regimes are observed: A low-Q-value regime where the aligned angular momentum component dominates over the random components, and a large-Q-value regime where the random components dominate and decrease the spin alignment

Target structure and in-beam electron spectra

The main features of the interplay between the target structure and the accelerated ion beam characteristics suitable for an in-beam e-gamma measurement are discussed in detail. In particular, the different types of ''spurious'' electron (and photon) spectra overlapped with in-beam internal conversion electrons (and discrete gamma-rays) are reviewed as well as the most efficient experimental methods used for their attenuation. Furthermore, the general characteristics of particle beams, targets and electron spectrometers required for prompt and delayed in-beam e, gamma and e-gamma measurements are also compared. Moreover, the relative magnitude of the electron line Doppler broadening corresponding to the perpendicular and the collinear geometry is briefly discussed and illustrated by a few in-beam e-gamma studies of Pm and Eu isotopes produced by accelerated ions (H-2(1) and Li-7(3)) bombarding very thin Nd(+C) backed targets. Finally the most recent developments made at Orsay towards multi e-gamma detector assemblies lead to a broad discussion concerning the most suitable targets to be inserted within such instrumental arrangements.</p