Observations of “pairing-free” Kπ = 1 + rotational bands in deformed odd-odd A ∼ 100 nuclei

Abstract

Rotational bands with K π = 1 + in the odd-odd nuclei 100,102 39Y and 102,104 41Nb are postulated from β − decay of t heir even-even parents. Each two-quasiparticle band has a moment of inertia very close to that of a rigid spheroidal nucleus with deformation β ∼ 0.3, hence these bands are nearly “pairing free”.