TILTED ROTATION AND BACKBENDING IN AN ODD-PROTON NUCLEUS

Tilted-axis rotation, arising from Fermi-aligned configurations, has b een observed for the first time to cause backbending in an odd-proton nucleus. In Re-181, two t-bands are found to be energetically favored relative to the usual rotation-aligned s-bands, presenting an alternat ive form of cold nuclear rotation. Interactions between the bands are weak, and unambiguous comparisons with tilted-axis-cranking calculatio ns can be made.