New sideband partners of the yrast bands built on the pi(h11/2)nu(h11/2) configuration were identified in 55Cs, 57La, and 61Pm N = 75 isotones of 134Pr. These bands form with 134Pr unique doublet-band systematics suggesting a common basis. Aplanar solutions of 3D tilted axis cranking calculations for triaxial shapes define left- and right-handed chiral systems out of the three angular momenta provided by the valence particles and the core rotation, which leads to spontaneous chiral symmetry breaking and the doublet bands. Small energy differences between the doublet bands suggest collective chiral vibrations.

A rotational band with seven gamma-ray transitions between states with spin 2 Planck's constant and 16 Planck's constant has been observed in the doubly magic, self-conjugate nucleus (40)(20)Ca(20). The measured transition quadrupole moment of 1.80(+0.39)(-0.29)eb indicates a superdeformed shape with a deformation beta(2) = 0.59(+0.11)(-0.07). The features of this band are explained by cranked relativistic mean field calculations to arise from an 8-particle 8-hole excitation.

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Three odd-odd Nϭ73 isotones, namely 128 Cs, 130 La, and 132 Pr, have been studied via ͑HI, xn␥) reactions. In all three cases, ⌬Iϭ1 side bands of the h 11/2 h 11/2 yrast bands were discovered. This extends the systematic observation of nearly degenerate h 11/2 h 11/2 doublet bands in the neighboring Nϭ75 isotones; these were interpreted as resulting from chiral symmetry breaking in the intrinsic body-fixed frame.